SEC Filing | Acumen Pharmaceuticals, Inc

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abos-20260630

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

___________________________

FORM 10-Q

___________________________

(Mark One)


x			QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended June 30, 2026


o			TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from_________to_________

Commission File Number: 001-40551

___________________________

Acumen Pharmaceuticals, Inc.

(Exact Name of Registrant as Specified in its Charter)

___________________________


Delaware						36-4108129
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification No.)

1210-1220 Washington Street, Suite 210, Newton, Massachusetts						02465
(Address of principal executive offices)						(Zip Code)

Registrant’s telephone number, including area code: (617) 344-4190

___________________________

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading symbol

Name of each exchange on which registered

Common stock, par value $0.0001 per share

ABOS

The Nasdaq Global Select Market

___________________________

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes x No o

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes x No o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.


Large accelerated filer	o	Accelerated filer	o
Non-accelerated filer	x	Smaller reporting company	x
		Emerging growth company	x

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No x

As of August 7, 2026, the registrant had 72,317,285 shares of common stock, par value $0.0001 per share, outstanding.

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		Page
PART I.	FINANCIAL INFORMATION	4
Item 1.	Financial Statements (Unaudited)	4
	Condensed Balance Sheets	4
	Condensed Statements of Operations and Comprehensive Loss	5

	Condensed Statements of Changes in Stockholders’ Equity	6
	Condensed Statements of Cash Flows	8
	Notes to Condensed Financial Statements	9
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	23
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	31
Item 4.	Controls and Procedures	32
PART II.	OTHER INFORMATION	33
Item 1.	Legal Proceedings	33
Item 1A.	Risk Factors	33
Item 2.	Unregistered Sales of Equity Securities, Use of Proceeds and Issuer Purchases of Equity Securities	34
Item 3.	Defaults Upon Senior Securities	34
Item 4.	Mine Safety Disclosures	34
Item 5.	Other Information	34
Item 6.	Exhibits	35
Signatures		36

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q contains forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995, about us and our industry that involve substantial risks and uncertainties. All statements other than statements of historical facts contained in this Quarterly Report on Form 10-Q, including statements regarding our future results of operations or financial condition, business strategy and plans and objectives of management for future operations, are forward-looking statements. In some cases, you can identify forward-looking statements because they contain words such as “anticipate,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will” or “would” or the negative of these words or other similar terms or expressions. These forward-looking statements include, but are not limited to, statements concerning the following:

•the sufficiency of our existing cash and cash equivalents and marketable securities to fund our future operating expenses and capital expenditure requirements;

•our ability to obtain funding for our operations, including funding necessary to develop and commercialize sabirnetug or ACU301 and ACU401, the Aβ oligomer-targeted Enhanced Brain Delivery™ (EBD™) product candidates that we licensed pursuant to our collaboration with JCR Pharmaceuticals Co. Ltd., in each case subject to obtaining necessary regulatory approvals, and our ability to continue as a going concern;

•the ability of our clinical trials to demonstrate the safety and efficacy of sabirnetug, and other positive results;

•the therapeutic potential of sabirnetug, including its potential for improved safety and efficacy, as compared to other monoclonal antibodies approved and/or in development, and of ACU301 and ACU401, as well as our expectations concerning our ongoing ALTITUDE-AD clinical trial and any future clinical trials we may conduct;

•the structure, focus, success, cost and timing of our development activities, nonclinical studies and clinical trials, and the reporting of data from those clinical trials;

•our plans relating to commercializing sabirnetug or any other product candidates that we may advance into clinical trials, subject to obtaining necessary regulatory approvals;

•our ability to attract and retain key scientific, clinical and operational personnel;

•our ability to contract with third-party suppliers and manufacturers and their ability to perform adequately;

•our reliance on third parties to conduct both preclinical studies related to ACU301 and ACU401 and clinical trials of sabirnetug, as well as any other product candidates we may develop, and to manufacture sabirnetug, ACU301 and ACU401, as well as any other product candidates we may develop, for nonclinical studies and clinical trials;

•the success of competing therapies that are or may become available;

•our plans and ability to obtain or protect our intellectual property rights, including extensions of existing patent terms where available or the use of data and market exclusivity to provide protection from generic or biosimilar versions of our product;

•the scope of protection we are able to establish and maintain for intellectual property rights covering sabirnetug, any other product candidates we may develop, and our technology;

•potential claims relating to or seeking to invalidate our intellectual property;

•existing regulations and regulatory developments in the United States and other jurisdictions;

•our ability to obtain and maintain regulatory approval of sabirnetug or any other product candidates we may develop, and any related restrictions, limitations and/or warnings in the label of any approved product candidate;

•the impacts of governmental legislation and regulations;

•our plans relating to the further development and manufacturing of sabirnetug, ACU301 and ACU401, as well as any other product candidates we may develop, including additional therapeutic indications we may pursue;

•our ability to develop and maintain our corporate infrastructure, including our ability to design and maintain an effective system of internal controls;

•our financial performance; and

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•our expectations regarding the time period during which we will be an emerging growth company under the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”).

You should not rely on forward-looking statements as predictions of future events. The outcome of the events described in these forward-looking statements is subject to risks, uncertainties and other factors described under the header “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, as filed with the Securities and Exchange Commission (the “SEC”) on March 26, 2026 (the “Annual Report”), and in our other filings with the SEC. Moreover, we operate in a very competitive and rapidly changing environment. New risks and uncertainties emerge from time to time, and it is not possible for us to predict all risks and uncertainties that could have an impact on the forward-looking statements contained herein. The results, events and circumstances reflected in the forward-looking statements may not be achieved or occur, and actual results, events or circumstances could differ materially from those described in the forward-looking statements.

The forward-looking statements made in this Quarterly Report on Form 10-Q relate only to events as of the date on which the statements are made, and we undertake no obligation to update them to reflect events or circumstances after the date of this Quarterly Report on Form 10-Q or to reflect new information or the occurrence of unanticipated events, except as required by law.

Unless the context otherwise indicates, references in this report to the terms “Acumen,” “the Company,” “we,” “our” and “us” refer to Acumen Pharmaceuticals, Inc.

We may announce material business and financial information to our investors using our investor relations website (investors.acumenpharm.com). We therefore encourage investors and others interested in Acumen to review the information that we make available on our website, in addition to following our filings with the SEC, webcasts, press releases and conference calls. Our website and information included in or linked to our website are not part of this Quarterly Report on Form 10-Q.

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PART I—FINANCIAL INFORMATION

Item 1. Financial Statements.

Acumen Pharmaceuticals, Inc.

Condensed Balance Sheets

(in thousands, except share and per share data)


	June 30, 2026		December 31, 2025
	(unaudited)
ASSETS
Current assets
Cash and cash equivalents	$	59,443	$	53,989
Marketable securities	50,754		62,876
Prepaid expenses and other current assets	5,316		5,387
Total current assets	115,513		122,252

Restricted cash	231		231
Other assets, long-term	263		350
Total assets	$	116,007	$	122,833
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities
Accounts payable	$	13,379	$	554
Accrued clinical trial expenses	6,263		10,616
Accrued expenses and other current liabilities	7,533		10,072
Debt, short-term	19,673		8,765
Total current liabilities	46,848		30,007
Debt, long-term	11,896		22,396
Total liabilities	58,744		52,403
Commitments and contingencies (Note 10)
Stockholders’ equity
Preferred stock, $0.0001 par value; 10,000,000 shares authorized and no shares issued and outstanding as of June 30, 2026 and December 31, 2025	—		—
Common stock, $0.0001 par value; 300,000,000 shares authorized as of June 30, 2026 and December 31, 2025; 72,314,714 and 60,575,369 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively	7		6
Additional paid-in capital	557,186		516,803
Accumulated deficit	(499,917)		(446,462)
Accumulated other comprehensive (loss) income	(13)		83
Total stockholders’ equity	57,263		70,430
Total liabilities and stockholders’ equity	$	116,007	$	122,833

The accompanying notes are an integral part of these unaudited condensed financial statements.

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Acumen Pharmaceuticals, Inc.

Condensed Statements of Operations and Comprehensive Loss

(in thousands, except share and per share data)

(unaudited)


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Operating expenses
Research and development	$	27,809	$	37,125	$	44,293	$	62,391
General and administrative	4,747		4,625		9,412		9,729
Total operating expenses	32,556		41,750		53,705		72,120
Loss from operations	(32,556)		(41,750)		(53,705)		(72,120)
Other income (expense)
Interest income	1,111		2,015		2,175		4,486
Interest expense	(1,094)		(1,046)		(2,163)		(2,069)
Change in fair value of embedded derivatives	(160)		(40)		300		150
Other expense, net	(19)		(129)		(62)		(193)
Total other (expense) income	(162)		800		250		2,374
Net loss	(32,718)		(40,950)		(53,455)		(69,746)
Other comprehensive gain (loss)
Unrealized (loss) gain on marketable securities	(34)		8		(96)		71
Comprehensive loss	$	(32,752)	$	(40,942)	$	(53,551)	$	(69,675)
Net loss per common share, basic and diluted	$	(0.45)	$	(0.68)	$	(0.79)	$	(1.15)
Weighted-average shares outstanding, basic and diluted	72,250,694		60,573,425		67,759,940		60,549,658

The accompanying notes are an integral part of these unaudited condensed financial statements.

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Acumen Pharmaceuticals, Inc.

Condensed Statements of Changes in Stockholders’ Equity

(in thousands, except share data)

(unaudited)

For the Three Months Ended June 30, 2026


	Common Stock			Additional Paid-in Capital		Accumulated Deficit		Accumulated Other Comprehensive Income (Loss)		Total Stockholders’ Equity
	Shares	Amount
Balance as of March 31, 2026	72,227,580	$	7	$	554,647	$	(467,199)	$	21	$	87,476
Private placement offering costs	—	—		(12)		—		—		(12)
Issuance of common stock for restricted stock units	64,000	—		—		—		—		—
Stock options exercised for cash	23,134	—		27		—		—		27
Unrealized loss on marketable securities	—	—		—		—		(34)		(34)
Stock-based compensation	—	—		2,524		—		—		2,524
Net loss	—	—		—		(32,718)		—		(32,718)
Balance as of June 30, 2026	72,314,714	$	7	$	557,186	$	(499,917)	$	(13)	$	57,263

For the Three Months Ended June 30, 2025


	Common Stock			Additional Paid-in Capital		Accumulated Deficit		Accumulated Other Comprehensive Income		Total Stockholders’ Equity
	Shares	Amount
Balance as of March 31, 2025	60,573,425	$	6	$	509,423	$	(353,923)	$	15	$	155,521


Unrealized gain on marketable securities	—	—		—		—		8		8

Stock-based compensation	—	—		2,498		—		—		2,498
Net loss	—	—		—		(40,950)		—		(40,950)
Balance as of June 30, 2025	60,573,425	$	6	$	511,921	$	(394,873)	$	23	$	117,077

The accompanying notes are an integral part of these unaudited condensed financial statements.

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Acumen Pharmaceuticals, Inc.

Condensed Statements of Changes in Stockholders’ Equity

(in thousands, except share data)

(unaudited)

For the Six Months Ended June 30, 2026


	Common Stock			Additional Paid-in Capital		Accumulated Deficit		Accumulated Other Comprehensive Income (Loss)		Total Stockholders’ Equity
	Shares	Amount
Balance as of December 31, 2025	60,575,369	$	6	$	516,803	$	(446,462)	$	83	$	70,430
Issuance of common stock in connection with the private placement, net of offering costs of $309	10,833,331	1		35,440		—		—		35,441
Issuance of common stock for restricted stock units, net of shares withheld for taxes	791,052	—		(149)		—		—		(149)
Stock options exercised for cash	114,962	—		172		—		—		172
Unrealized loss on marketable securities	—	—		—		—		(96)		(96)
Stock-based compensation	—	—		4,920		—		—		4,920
Net loss	—	—		—		(53,455)		—		(53,455)
Balance as of June 30, 2026	72,314,714	$	7	$	557,186	$	(499,917)	$	(13)	$	57,263

For the Six Months Ended June 30, 2025


	Common Stock			Additional Paid-in Capital		Accumulated Deficit		Accumulated Other Comprehensive Income (Loss)		Total Stockholders’ Equity
	Shares	Amount
Balance as of December 31, 2024	60,094,083	$	6	$	506,985	$	(325,127)	$	(48)	$	181,816
Issuance of common stock for restricted stock units, net of shares withheld for taxes	446,756	—		(73)		—		—		(73)
Stock options exercised for cash	32,586	—		37		—		—		37
Unrealized gain on marketable securities	—	—		—		—		71		71
Stock-based compensation	—	—		4,972		—		—		4,972
Net loss	—	—		—		(69,746)		—		(69,746)
Balance as of June 30, 2025	60,573,425	$	6	$	511,921	$	(394,873)	$	23	$	117,077

The accompanying notes are an integral part of these unaudited condensed financial statements.

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Acumen Pharmaceuticals, Inc.

Condensed Statements of Cash Flows

(in thousands)

(unaudited)


	Six Months Ended June 30,
	2026		2025
Cash flows from operating activities
Net loss	$	(53,455)	$	(69,746)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	23		31
Stock-based compensation expense	4,920		4,972
Amortization of premiums and accretion of discounts on marketable securities, net	(161)		(644)
Change in fair value of embedded derivatives	(300)		(150)
Amortization of right-of-use asset	68		61
Realized gain on marketable securities	(6)		(3)
Noncash interest expense	708		613

Changes in operating assets and liabilities:
Prepaid expenses and other current assets	71		1,714
Other long-term assets	(4)		18
Accounts payable	12,825		(3,545)
Accrued clinical trial expenses	(4,353)		(4,236)
Accrued expenses and other liabilities	(2,539)		4,962
Net cash used in operating activities	(42,203)		(65,953)
Cash flows from investing activities
Purchases of marketable securities	(40,823)		(38,056)
Proceeds from maturities and sales of marketable securities	53,016		105,316
Purchases of property and equipment	—		(88)
Net cash provided by investing activities	12,193		67,172
Cash flows from financing activities
Proceeds from private placement, net of offering costs	35,441		—
Proceeds from exercise of stock options	172		37
Repurchase of common shares to pay employee withholding taxes	(149)		(73)
Net cash provided by (used in) financing activities	35,464		(36)
Net change in cash and cash equivalents and restricted cash	5,454		1,183
Cash and cash equivalents and restricted cash at the beginning of the period	54,220		35,859
Cash and cash equivalents and restricted cash at the end of the period	$	59,674	$	37,042
Supplemental disclosure of cash flow information
Cash paid for income taxes	$	—	$	—
Cash paid for interest	$	1,463	$	1,464

The accompanying notes are an integral part of these unaudited condensed financial statements.

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

NOTE 1. DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS

Acumen Pharmaceuticals, Inc. (“Acumen” or the “Company”) was incorporated in 1996 in the state of Delaware. Acumen is a clinical-stage biopharmaceutical company developing a novel disease-modifying approach targeting what the Company believes to be a key underlying cause of Alzheimer’s disease (“AD”). Alzheimer’s disease is a progressive neurodegenerative disease of the brain that leads to loss of memory and cognitive functions and ultimately results in death. The Company’s scientific founders pioneered research on soluble amyloid-beta oligomers (“AβOs”), which are globular assemblies of the amyloid-beta (“Aβ”) peptide that are distinct from Aβ monomers and amyloid plaques. Based on decades of research and supporting evidence, AβOs have gained increasing scientific acceptance as a primary toxin involved in the initiation and propagation of AD pathology. The Company is currently focused on advancing a targeted immunotherapy drug candidate, sabirnetug, in its Phase 2 ALTITUDE-AD clinical trial, and plans to announce top-line results in late 2026. Top-line results are expected to include the difference compared to placebo after 18 months as measured by the Integrated Alzheimer’s Disease Rating Scale, our primary clinical efficacy endpoint, as well as key secondary endpoints, such as Clinical Dementia Rating – Sum of the Boxes, certain safety measures such as adverse event rates, including rates of amyloid-related imaging abnormalities, and key fluid biomarkers. ALTITUDE-AD is a randomized, double-blind, placebo-controlled, three-arm clinical trial designed to evaluate the clinical efficacy, safety and tolerability of sabirnetug with up to 180 participants per arm for a total of 542 participants with mild cognitive impairment or mild dementia due to AD. Sabirnetug is a recombinant humanized immunoglobulin gamma 2 monoclonal antibody that was designed to selectively target AβOs. In July 2023, the Company announced top-line results from its Phase 1 INTERCEPT-AD clinical trial of sabirnetug, which demonstrated that sabirnetug met the primary and secondary objectives of this clinical trial in 62 participants with early AD. In addition, the Company is investigating a subcutaneous dosing option of sabirnetug, as well as a blood-brain barrier-penetrating, Aβ oligomer-targeted Enhanced Brain Delivery™ (EBD™) therapy for AD.

In June 2026, the Company announced the nomination of two EBD development candidates for the treatment of AD pursuant to its collaboration agreement with JCR Pharmaceuticals Co. Ltd. (“JCR”) and the exercise of its option pursuant to the collaboration agreement to license and develop such development candidates. See additional information in Note 10. Commitments and Contingencies.

The Company is subject to the uncertainty of whether its intellectual property will develop into successful commercial products.

Liquidity, Capital Resources and Going Concern

In accordance with Accounting Standards Codification (“ASC”) 205-40, Presentation of Financial Statements-Going Concern, the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern. The Company has incurred operating losses since inception. As of June 30, 2026, the Company had an accumulated deficit of $499.9 million and had cash and cash equivalents and marketable securities of $110.2 million. The Company expects to incur additional losses for the foreseeable future as it continues its research and development activities and will need to raise additional capital to fully implement its business plan and to fund its operations. Until such time, if ever, as the Company can generate revenue sufficient to achieve profitability, the Company expects to finance its operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. There can be no assurance that any such financing will be available to the Company at adequate levels and on a timely basis, or such agreements may not be available on terms acceptable to the Company, or at all. The Company may be required to delay, limit, reduce or terminate its product discovery and development activities or future commercialization efforts if it is unable to maintain sufficient financial resources, and its business, financial condition and results of operations will be materially and adversely affected. The Company expects that its current balance of cash and cash equivalents and marketable securities may not be sufficient to fund its operations for at least 12 months from the date of issuance of these financial statements. The Company’s cash forecast contains estimates and assumptions related to its ongoing clinical trial and other research and development expenses, and the Company cannot predict the amount or timing of all expenditures with certainty. Accordingly, the Company has concluded that substantial doubt exists about its ability to continue as a going concern.

The accompanying unaudited condensed financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business, and do not include any adjustments relating to recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might be necessary, should the Company be unable to continue as a going concern.

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

NOTE 2. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. In the opinion of management, the unaudited condensed financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position and results of its operations and its cash flows for the periods presented. Certain information and note disclosures normally included in the Company’s annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. These unaudited condensed financial statement results are not necessarily indicative of results to be expected for the full fiscal year or any future period.

A description of the Company’s significant accounting policies is included in the Company’s Annual Report. There have been no material changes in the Company’s significant accounting policies to those previously disclosed in the Company’s Annual Report.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed financial statements, as well as the reported amounts of expenses during the reporting periods. These estimates and assumptions are based on the Company’s historical experience, and on various other factors that management believes are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources.

Actual results may differ from these estimates under different assumptions or conditions. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected. The more significant estimates and assumptions by management include, among others: the valuation of embedded derivatives within the Company’s debt, long-term and accruals for clinical trial expenses and other research and development expenses.

Cash and Cash Equivalents and Restricted Cash

The Company considers all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. All of the Company’s cash equivalents have liquid markets and high credit ratings. The Company had $59.3 million and $53.7 million in cash equivalents as of June 30, 2026 and December 31, 2025, respectively.

Restricted cash primarily consists of deposited cash collateral for the Company’s credit card program.

The following table provides a reconciliation of cash, cash equivalents and restricted cash from the balance sheets to the statements of cash flows (in thousands):


	June 30, 2026		December 31, 2025
Cash and cash equivalents	$	59,443	$	53,989
Restricted cash	231		231
Total cash, cash equivalents and restricted cash	$	59,674	$	54,220

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents and marketable securities. The Company maintains deposits in financial institutions in excess of government insured limits. Management believes that the Company is not exposed to significant credit risk as the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

quality. The Company has not experienced any losses due to credit risk on such accounts during any of the periods presented.

Net Loss Per Share of Common Stock

Basic net loss per share of common stock is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible debt, stock options, restricted stock units (“RSUs”) and warrants, which would result in the issuance of incremental shares of common stock. However, potential shares of common stock are excluded if their effect is anti-dilutive. For diluted net loss per share, the weighted-average number of shares of common stock is the same for basic net loss per share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive.

Potentially dilutive securities not included in the calculation of diluted net loss per share of common stock as of the periods presented, because to do so would be anti-dilutive, were as follows:


	June 30,
	2026	2025
Shares issuable upon exercise of stock options	15,441,098	12,539,238
Shares issuable upon conversion election for term loan facility	988,142	988,142
Shares issuable upon exercise of warrant	730,769	730,769
Unvested RSUs	3,058,771	1,917,293
Total	20,218,780	16,175,442

Segment Information

Operating segments are defined as components of an enterprise for which separate discrete financial information is available for evaluation by the chief operating decision maker (“CODM”) in deciding how to allocate resources and assess performance. The Company’s CODM is its chief executive officer. The Company has one operating segment focused on the research and development of treatments for AD, including both sabirnetug and its EBD therapy. See Note 9 – Segment Reporting.

Recently Issued Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”) or other standard setting bodies that the Company adopts as of the specified effective date. Unless otherwise discussed below, the Company does not believe that the adoption of recently issued standards have or may have a material impact on its financial statements and disclosures.

In November 2024, the FASB issued Accounting Standards Update (“ASU”) 2024-04, Debt – Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments. The standard is intended to clarify the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion. The standard is effective for annual periods beginning after December 15, 2025, and for interim periods within those annual reporting periods. As of June 30, 2026, the Company had no induced conversions. The Company adopted this standard on a prospective basis on January 1, 2026. The adoption of this standard did not have a material impact on the Company’s financial statements and related disclosures.

In November 2024, the FASB issued ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. The standard is intended to require more detailed disclosures about specified categories of expenses, including employee compensation, depreciation and amortization, included in certain expense captions presented on the face of the income statement. The ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 31, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

presented in the financial statements. The Company is evaluating the potential impact of this adoption on its financial statements and related disclosures.

In December 2025, the FASB issued ASU 2025-11, Interim Reporting - Narrow Scope Improvements. The standard is intended to improve the guidance in Topic 270, Interim Reporting, by improving the navigability of the required

interim disclosures and clarifying when that guidance is applicable. The amendments in this update clarify interim disclosure requirements and the applicability of Topic 270. The amendments also provide additional guidance on what disclosures should be provided in interim reporting periods. The amendments in this update are effective for interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. Upon adoption, the amendments may be applied on a prospective or retrospective basis. The Company is evaluating the potential impact of this adoption on its financial statements and related disclosures.

NOTE 3. MARKETABLE SECURITIES

The Company’s marketable securities consisted of the following (in thousands):


	June 30, 2026
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Available-for-sale securities, short-term
Corporate debt securities	$	28,944	$	10	$	(12)	$	28,942

Government and agency - U.S.	21,823		—		(11)		21,812
Total available-for-sale securities, short-term	$	50,767	$	10	$	(23)	$	50,754


	December 31, 2025
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Available-for-sale securities, short-term
Corporate debt securities	$	62,793	$	88	$	(5)	$	62,876


Total available-for-sale securities, short-term	$	62,793	$	88	$	(5)	$	62,876

The following tables summarize the amount of unrealized losses, defined as the amount by which the amortized cost exceeds fair value, and the related fair value of available-for-sale marketable securities with unrealized losses, which have been segregated into two categories: those that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for 12 or more months (in thousands):


	June 30, 2026
	Less than 12 Months				Greater than 12 Months				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate debt securities	$	12,395	$	(12)	$	—	$	—	$	12,395	$	(12)
Government and agency - U.S.	21,812		(11)		—		—		21,812		(11)
Total	$	34,207	$	(23)	$	—	$	—	$	34,207	$	(23)


	December 31, 2025
	Less than 12 Months				Greater than 12 Months				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate debt securities	$	6,036	$	(3)	$	5,119	$	(2)	$	11,155	$	(5)

Total	$	6,036	$	(3)	$	5,119	$	(2)	$	11,155	$	(5)

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

As of June 30, 2026, all of the Company’s available-for-sale securities mature in less than one year. As noted in the table above, none of the Company’s available-for-sale marketable securities as of June 30, 2026 have been in an unrealized loss position for more than 12 months. As of December 31, 2025, some of the Company’s available-for-sale securities had been in an unrealized loss position for more than 12 months; however, the losses were immaterial. The Company does not intend to sell any of its available-for-sale securities and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases, which may be at maturity. No credit losses were recognized on the Company’s available-for-sale securities during the three and six months ended June 30, 2026 and 2025. The Company recorded immaterial realized gains during the six months ended June 30, 2026 and 2025. No realized gains were recorded during the three months ended June 30, 2026 and 2025.

NOTE 4. FAIR VALUE MEASUREMENTS

The Company’s financial assets and liabilities subject to fair value measurement on a recurring basis and the level of inputs used for such measurements were as follows (in thousands):


	Fair value measurements as of June 30, 2026 using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value at June 30, 2026
Assets included in:
Cash and cash equivalents
Money market securities	$	59,289	$	—	$	—	$	59,289

Marketable securities
Corporate debt securities	—		28,942		—		28,942
Government and agency - U.S.	—		21,812		—		21,812
Total fair value	$	59,289	$	50,754	$	—	$	110,043
Liabilities included in:
Debt, long-term
Embedded derivatives liability	$	—	$	—	$	1,130	$	1,130
Total fair value	$	—	$	—	$	1,130	$	1,130


	Fair value measurements as of December 31, 2025 using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value at December 31, 2025
Assets included in:
Cash and cash equivalents
Money market securities	$	53,708	$	—	$	—	$	53,708
Marketable securities
Corporate debt securities	—		62,876		—		62,876


Total fair value	$	53,708	$	62,876	$	—	$	116,584
Liabilities included in:
Debt, long-term
Embedded derivatives liability	$	—	$	—	$	1,430	$	1,430
Total fair value	$	—	$	—	$	1,430	$	1,430

The carrying values reported in the Company’s condensed balance sheets for cash (excluding cash equivalents, which are recorded at fair value on a recurring basis), restricted cash, accounts payable, accrued clinical trial expenses and accrued

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

expenses and other current liabilities are reasonable estimates of their fair values due to the short-term nature of these items.

The carrying amount of the Company’s debt approximates fair value due to its variable market interest rate and management’s opinion that current rates and terms that would be available to the Company with the same maturity and security structure would be essentially equivalent to that of the Company’s debt, long-term. Certain features of the Company’s term loan facility (the “Term Loan”) were determined to be embedded derivatives requiring separate measurement from the loan host instrument. For additional information regarding the Term Loan, see Note 6. Debt.

The fair value of the Company’s money market funds is determined using quoted market prices in active markets for identical assets.

The fair value for the available-for-sale marketable securities is determined based on valuation models using inputs that are observable either directly or indirectly (Level 2 inputs), such as quoted prices for similar assets or liabilities, yield curve, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments or debt, broker and dealer quotes, as well as other relevant economic measures.

The following table presents changes in Level 3 liabilities measured at fair value for the six months ended June 30, 2026 (in thousands):


Balance, December 31, 2025	$	1,430
Change in fair value of embedded derivatives	(300)
Balance, June 30, 2026	$	1,130

NOTE 5. SUPPLEMENTAL FINANCIAL INFORMATION

Prepaid expenses and other assets as of June 30, 2026 and December 31, 2025 consisted of the following (in thousands):


	June 30, 2026
	Prepaid Expenses and Other Current Assets		Other Assets, Long-Term		Total Prepaid Expenses and Other Assets
Research and development service agreements	$	3,763	$	24	$	3,787
Other receivables	1,005		—		1,005
Dues and subscriptions	246		—		246
Prepaid insurance	128		—		128
Property and equipment, net (1)	—		80		80
Right-of-use asset	—		72		72
Other	174		87		261
Total	$	5,316	$	263	$	5,579

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)


	December 31, 2025
	Prepaid Expenses and Other Current Assets		Other Assets, Long-Term		Total Prepaid Expenses and Other Assets
Research and development service agreements	$	3,527	$	29	$	3,556
Other receivables	625		—		625
Prepaid insurance	601		—		601
Dues and subscriptions	368		—		368
Right-of-use asset	—		140		140
Property and equipment, net (1)	—		103		103
Other	266		78		344
Total	$	5,387	$	350	$	5,737

(1) As of June 30, 2026 and December 31, 2025, accumulated depreciation totaled approximately $0.1 million and $0.2 million, respectively.

Accrued expenses and other current liabilities as of June 30, 2026 consisted of the following (in thousands):



	Accrued Expenses and Other Current Liabilities
Research and development	4,638
Compensation and other employee liabilities	$	2,409
Interest	241
Operating lease liability	77
Other	168
Total	$	7,533

Accrued expenses and other current liabilities as of December 31, 2025 consisted of the following (in thousands):



	Accrued Expenses and Other Current Liabilities
Research and development	$	5,427
Compensation and other employee liabilities	4,066
Interest	249
Operating lease liability	150
Other	180
Total	$	10,072

NOTE 6. DEBT

Term Loan

On November 10, 2023, the Company entered into a Loan and Security Agreement with K2 HealthVentures LLC (the “Loan Agreement”). The Loan Agreement provided the Company with a Term Loan in the aggregate principal amount of $50.0 million, of which the Company borrowed $30.0 million in the first tranche upon closing. The remaining $20.0 million is available for borrowing upon the Company’s request based on review of certain information and discretionary approval from the lenders. The principal amount of the Term Loan outstanding under the Loan Agreement bears interest per annum at the greater of (i) 9.65% or (ii) the sum of the prime rate last quoted in The Wall Street Journal plus 1.15% for such interest period. The Term Loan matures on November 1, 2027, and can be extended to November 1, 2028 if the Company achieves certain financing milestones. The Loan Agreement provides for a final payment fee of an additional

Table of Contents

Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

$1.6 million (the “Final Payment”) due upon repayment of the Term Loan. As security for its obligations under the Loan Agreement, the Company granted the lenders a security interest in substantially all of the Company’s assets (other than intellectual property).

The principal and interest of the Term Loan are to be repaid in equal monthly installments beginning on July 1, 2026 through the maturity of the Loan Agreement. The Loan Agreement allows prepayment of the entire Term Loan or a portion of the Term Loan of more than $5.0 million, provided that any partial prepayment will leave outstanding borrowings of at least $15.0 million.

The lenders can elect to convert up to $2.5 million of the Term Loan (the “Conversion Amount”) into the Company’s common stock at a conversion price of $2.53 (the “Conversion Option”). Prior to the consummation of the Company’s Private Placement (as defined below), which constituted the Next Qualified Financing (as defined in the Loan Agreement) pursuant to which the Company received aggregate gross proceeds of at least $20.0 million, the lenders also had an option to convert the Conversion Amount at a conversion price equal to the lowest effective cash price per share of securities issued in such Qualified Financing (the “Share-Settled Redemption”). The Conversion Option and Share-Settled Redemption within the Loan Agreement were required to be bifurcated as a single compound embedded derivative (the “Embedded Derivatives”) at fair value, with subsequent changes in fair value recognized in the statements of operations and comprehensive loss.

On March 13, 2026, the Company entered into a securities purchase agreement with certain institutional and accredited investors for a private placement (the “Private Placement”) of shares of the Company’s common stock. See additional information regarding the Private Placement in Note 7. Stockholders' Equity. The Private Placement was a Qualified Financing under the terms of the Loan Agreement and the lenders did not elect to convert the Conversion Amount at the time of the Private Placement. Therefore, the only remaining embedded derivative under the Loan Agreement is the Conversion Option (the “Embedded Derivative”) as the Share-Settled Redemption is no longer an election available to the lenders.

In accordance with the Loan Agreement, the Company issued an equity-classified warrant to purchase 730,769 shares of common stock (the “Loan Warrant”), with an initial allocated fair value of $1.1 million. See additional discussion in Note 7. Stockholders’ Equity.

The initial recognition of the direct fees of $0.5 million, the Final Payment of $1.6 million, the fair value of the Embedded Derivatives at issuance of the Term Loan of $1.2 million and the fair value of the Loan Warrant of $1.1 million for the Loan Agreement resulted in a discount of $4.4 million, which is being amortized to interest expense over the term of the Loan Agreement using the effective interest method.

Outstanding debt consisted of the following (in thousands):


	June 30, 2026		December 31, 2025
Principal value of Term Loan, including Final Payment of $1,635	$	31,635	$	31,635
Fair value of bifurcated embedded derivatives	1,130		1,430
Unamortized debt discount	(1,196)		(1,904)
Total	31,569		31,161
Less: debt, short-term	19,673		8,765
Total debt, long-term	$	11,896	$	22,396

The following table provides the components of interest expense (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Interest expense based on the coupon interest rate of the outstanding debt	$	732	$	732	$	1,455	$	1,456
Accretion of debt discount	362		314		708		613
Total interest expense related to debt	$	1,094	$	1,046	$	2,163	$	2,069

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

For the three and six months ended June 30, 2026 the effective interest rate for the Term Loan was 14.8% and 14.6%, respectively. For the three and six months ended June 30, 2025 the effective interest rate for the Term Loan was 14.1% and 14.0%, respectively.

As of June 30, 2026, the aggregate principal payments due for the Term Loan by year are as follows (in thousands):


Year ended December 31, 2026	$	10,104
Year ended December 31, 2027	21,531
Total principal payments due for Term Loan	$	31,635

NOTE 7. STOCKHOLDERS’ EQUITY

Authorized Shares

As of June 30, 2026, the total number of shares of capital stock authorized to be issued per the Company’s Amended and Restated Certificate of Incorporation is 310,000,000, with 10,000,000 shares designated as preferred stock with a par value of $0.0001 per share, and 300,000,000 shares designated as common stock with a par value of $0.0001 per share. Each share of common stock issued and outstanding is entitled to one vote.

Private Placement

On March 13, 2026, the Company entered into the Private Placement of 10,833,331 shares of the Company’s common stock, at an offering price of $3.30 per share. The Private Placement closed on March 16, 2026, for aggregate gross proceeds of approximately $35.7 million, before deducting offering costs of approximately $0.3 million. The Company intends to use the net proceeds from the Private Placement to primarily support its EBD program, including ongoing preclinical development work to support the nomination of a lead clinical candidate molecule, and for working capital and other general corporate purposes. The Company filed a shelf registration statement on Form S-3 with the Securities and Exchange Commission on March 26, 2026 to register the shares sold in the Private Placement.

Shelf Registration and At The Market Equity Offering

On July 1, 2022, the Company filed a shelf registration statement on Form S-3 (the “2022 Registration Statement”). Pursuant to the 2022 Registration Statement, the Company may offer and sell securities having an aggregate public offering price of up to $200.0 million.

In connection with the filing of the 2022 Registration Statement, the Company also entered into a sales agreement (the “Sales Agreement”) with BofA Securities, Inc. (“BofA”) and Stifel, Nicolaus & Company, Incorporated (“Stifel”) as sales agents, pursuant to which the Company may issue and sell shares of its common stock for an aggregate offering price of up to $50.0 million under an at-the-market offering program (the “ATM”), which was included in the $200.0 million of securities that were registered for sale pursuant to the 2022 Registration Statement. On April 23, 2023, the Company entered into an amendment to the Sales Agreement (as amended, the “Amended Sales Agreement”) to add BTIG, LLC (“BTIG”) as a sales agent under the Amended Sales Agreement (BTIG, BofA and Stifel are collectively referred to as the “Sales Agents”). Pursuant to the Amended Sales Agreement, the Company will pay the Sales Agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of the Company’s common stock made under the ATM. The Company is not obligated to make any sales of shares of its common stock under the ATM.

During the six months ended June 30, 2026 and 2025, the Company did not sell any shares of common stock under the ATM. The Company has issued shares of common stock for aggregate gross proceeds of $12.2 million under the ATM since the program’s inception.

On March 27, 2024, the Company filed a shelf registration statement on Form S-3 (the “2024 Registration Statement”). Pursuant to the 2024 Registration Statement, the Company may offer and sell securities having an aggregate public offering price of up to $200.0 million. On November 13, 2025, the Company filed a prospectus supplement to the 2024 Registration Statement with respect to its ATM, designating up to $50.0 million of the $200.0 million of securities that may be offered pursuant to the 2024 Registration Statement for issuance under the ATM.

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

Restricted Stock Units

During the six months ended June 30, 2026 and 2025, the Company issued 791,052 and 446,756 shares, respectively, of its common stock in settlement of fully vested RSUs.

Common Stock Warrant

On November 10, 2023, in accordance with the Loan Agreement, the Company issued the Loan Warrant to purchase 730,769 shares of its common stock at an exercise price of $1.95 with a ten-year contractual term and an allocated fair value of $1.1 million. This equity-classified warrant is outstanding as of June 30, 2026.

NOTE 8. STOCK-BASED COMPENSATION

2021 Equity Incentive Plan

The 2021 Equity Incentive Plan (the “2021 Plan”), which provides for the grant of incentive stock options to employees and the grant of nonstatutory stock options, stock appreciation rights, restricted stock awards, RSUs, performance awards and other forms of stock awards to employees, directors and consultants, became effective on June 30, 2021. The 2021 Plan is a successor to the Company’s Amended and Restated Stock Performance Plan that was adopted by the Company’s board of directors and stockholders on April 8, 2013 (as amended from time to time, most recently on November 20, 2020, the “2013 Plan”). Following the effectiveness of the 2021 Plan, no further grants may be made under the 2013 Plan; however, any outstanding equity awards granted under the 2013 Plan continue to be governed by the terms of the 2013 Plan. As of June 30, 2026, there were 3,028,936 options outstanding under the 2013 Plan. On June 3, 2026, Acumen’s stockholders approved the adoption of the Company’s Amended and Restated 2021 Equity Incentive Plan (the “Amended and Restated 2021 Plan”) to (i) increase the number of shares available for issuance by 10,000,000 shares, (ii) remove the automatic “evergreen” share pool increase provision, and (iii) prohibit repricing of stock options without stockholder approval (other than in connection with certain corporate transactions).

Prior to the effectiveness of the Amended and Restated 2021 Plan, the number of shares of common stock reserved for issuance under the 2021 Plan automatically increased on January 1 of each calendar year, in an amount equal to 5% of the total number of shares of common stock outstanding on December 31 of the fiscal year before the date of each automatic increase, or a lesser number of shares determined by the board of directors prior to the applicable January 1. On January 1, 2026, the number of shares of common stock reserved for issuance under the 2021 Plan automatically increased by 3,028,768 shares.

The maximum number of shares of common stock that may be issued upon the exercise of incentive stock options under the Amended and Restated 2021 Plan is 29,040,630. As of June 30, 2026, a total of 30,702,193 shares were authorized for issuance under the Amended and Restated 2021 Plan and 10,453,627 shares remained available for issuance under the Amended and Restated 2021 Plan.

The Company recorded stock-based compensation expense related to stock options and RSUs in the following expense categories of its condensed statements of operations and comprehensive loss for the periods shown (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
General and administrative	$	1,462	$	1,491	$	2,828	$	2,983
Research and development	1,062		1,007		2,092		1,989
Total stock-based compensation	$	2,524	$	2,498	$	4,920	$	4,972

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

Stock Options

The Black-Scholes option-pricing model was used to estimate the fair value of stock options granted during the six months ended June 30, 2026 and 2025 with the following weighted average assumptions:


	Six Months Ended June 30,
	2026	2025
Risk-free interest rate	3.70% - 4.34%	3.93% - 4.52%
Expected term (in years)	1.0 - 6.0	1.0 - 6.0
Expected volatility	84% - 90%	76% - 92%
Expected dividend yield	0%	0%

The weighted average grant date fair value of options granted during the six months ended June 30, 2026 and 2025 was $1.47 per share and $1.26 per share, respectively.

Stock options granted after December 31, 2017 generally vest monthly over a range of 12 to 48 months or vest monthly over a total of 48 months following a one-year cliff and all have a 10-year contractual term. Beginning January 1, 2024, stock options granted to consultants vest quarterly over a one-year period, provided that such consultants continue to perform services as dictated by their respective consulting agreements with the Company. Annual option awards issued to members of the Company’s board of directors vest in full on the first anniversary of the grant date. Stock options granted prior to December 31, 2017 were either fully vested upon grant or generally vested monthly over a range of three to 24 months and also have a 10-year term. The Company’s common stock became publicly traded in July 2021. Prior to January 1, 2025, the Company lacked sufficient company-specific historical and implied volatility information for its common stock and estimated its expected stock volatility using a weighted average blend of historical volatility of a publicly traded set of peer companies, as well as its own historical volatility. Beginning on January 1, 2025, based on the availability of sufficient historical trading data of the Company’s common stock, the Company began using its historical volatility to estimate expected stock volatility. Due to the lack of historical exercise history, the expected term of the Company’s stock options has been determined using the “simplified” method for awards. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is zero based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

The following table reflects summarized stock option activity during the six months ended June 30, 2026:


	Stock Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding as of December 31, 2025	12,578,766	$	3.46
Granted	3,135,539	$	1.97
Exercised	(114,962)	$	1.50
Forfeited	(65,286)	$	2.11
Expired	(92,959)	$	2.32
Outstanding as of June 30, 2026	15,441,098	$	3.18	7.1	$	362
Vested and exercisable as of June 30, 2026	9,634,417	$	3.61	6.0	$	351

The intrinsic value of stock options exercised during the six months ended June 30, 2026 was approximately $0.1 million and the intrinsic value of stock options exercised during the six months ended June 30, 2025 was immaterial. As of June 30, 2026, total unrecognized compensation costs related to unvested stock option awards were approximately $10.7 million, which the Company expects to recognize over a weighted-average period of approximately 2.3 years.

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

Restricted Stock Units

RSUs granted to employees vest in equal annual installments on the first three anniversaries of the grant date and RSUs granted to members of the Company’s board of directors vest in full on the first anniversary of the grant date.

The following table reflects summarized RSU activity during the six months ended June 30, 2026:


	Number of Shares	Weighted Average Grant Date Fair Value
Unvested as of December 31, 2025	1,907,976	$	2.93
Granted	2,045,683	$	1.97
Vested	(869,203)	$	3.28
Forfeited	(25,685)	$	1.93
Unvested as of June 30, 2026	3,058,771	$	2.20

As of June 30, 2026, total unrecognized compensation costs related to unvested RSUs were approximately $5.1 million, which the Company expects to recognize over a weighted-average period of approximately 1.9 years.

Employee Stock Purchase Plan

The 2021 Employee Stock Purchase Plan (the “ESPP”), which permits employees to purchase shares of common stock, became effective on June 30, 2021. The number of shares of common stock reserved for issuance automatically increases on January 1 of each calendar year through January 1, 2031, by the lesser of (1) 1% of the total number of shares of common stock outstanding on the last day of the fiscal year before the date of the automatic increase, and (2) 800,000 shares; provided, however, that before the date of any such increase, the board of directors may determine that such increase will be less than the amount set forth in clauses (1) and (2). On January 1, 2026, the number of shares of common stock reserved for issuance under the ESPP automatically increased by 605,754 shares. As of June 30, 2026, there are a total of 2,975,783 shares reserved for issuance under the ESPP and there have been no purchases of shares under the ESPP, as the ESPP has not yet been implemented.

NOTE 9. SEGMENT REPORTING

The Company manages its operations as a single reportable segment which includes research and development efforts for the treatment of AD. The CODM assesses performance and allocates resources for the segment based on segment net loss, which is reported on the statement of operations and comprehensive loss as net loss. The CODM uses segment net loss to monitor spending, assess performance for the Company and management, evaluate the progress of completing corporate goals and make decisions regarding the allocation of resources. Substantially all long-lived assets are located in the United States. The measure of segment assets is reported on the balance sheet as total assets.

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

The following table presents selected financial information about the Company’s single operating segment for the three and six months ended June 30, 2026 and 2025 (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Operating expenses
Research and development
External costs	$	22,418	$	31,559	$	33,177	$	50,986
Internally managed costs (1)	4,329		4,556		9,024		9,409
General and administrative (2)	3,274		3,121		6,561		6,722
Other segment expenses (3)	2,535		2,514		4,943		5,003
Other expense (income), net	162		(800)		(250)		(2,374)
Segment net loss	$	32,718	$	40,950	$	53,455	$	69,746

(1) Includes Company-managed research, consultants and contractors, as well as internal personnel and operating expenses, and excludes stock-based compensation expense and depreciation.

(2) Excludes stock-based compensation expense and depreciation.

(3) Other segment expenses include stock-based compensation expense and depreciation.

NOTE 10. COMMITMENTS AND CONTINGENCIES

The Company is not a party to any material legal proceedings and is not aware of any pending or threatened claims. From time to time, the Company may be subject to various legal proceedings and claims that arise in the ordinary course of its business activities.

In July 2025, the Company entered into a collaboration, option and license agreement with JCR to develop an Aß oligomer-targeted EBD™ therapy for the treatment of AD. Under the terms of the agreement, the Company paid JCR an upfront license payment, which was recognized as in-process research and development expense during the year ended December 31, 2025. In June 2026, the Company nominated two EBD development candidates for the treatment of AD pursuant to its collaboration agreement with JCR and exercised its exclusive option to license and develop such development candidates. The option exercise payment of $9.25 million was recognized as in-process research and development expense during the three and six months ended June 30, 2026 and was paid to JCR in July 2026. JCR will also be eligible to receive future milestone payments of up to $40.0 million related to development, and up to $515.0 million related to sales, for a total of up to $555.0 million, as well as single-digit percentage royalties on sales of any products that emerge from the collaboration.

In November 2023, the Company entered into a Non-exclusive Collaboration and License Agreement (the “Halozyme License Agreement”) with Halozyme, Inc. (“Halozyme”). Under the terms of the Halozyme License Agreement, Halozyme granted the Company a non-exclusive license to Halozyme’s drug delivery technology for the development of a subcutaneous formulation of sabirnetug (such combination, the “Halozyme Product”). In January 2024, the Company paid a seven-figure upfront license payment for the Halozyme Product. The Company is required to make milestone payments upon the achievement of certain development and commercialization events with respect to the Halozyme Product, as well as milestone payments based on achievement of certain net sales levels of the Halozyme Product. The Company will also make single-digit royalty payments based on worldwide net sales of the Halozyme Product. The upfront license payment and milestones are recorded as in-process research and development expense when incurred.

In November 2022, the Company entered into a License Agreement (the “Lonza License Agreement”) with Lonza Sales AG (“Lonza”). Under the terms of the Lonza License Agreement, Lonza granted the Company a worldwide non-exclusive license to use Lonza’s glutamine synthetase gene expression system to manufacture and commercialize sabirnetug (the “Lonza Product”). Under the terms of the Lonza License Agreement, in consideration of the licenses and consents granted to the Company, the Company paid an upfront fee of 1.0 million Swiss Francs. The Company is also required to pay certain royalties upon commercialization and annual payments on a country-by-country basis in respect of the manufacturing and sale of the Lonza Product, which include (i) a royalty of less than 1% on net sales where Lonza manufactures the Lonza Product, (ii) an annual royalty payment in Swiss Francs in the low six figures and a royalty of less

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Acumen Pharmaceuticals, Inc.

Notes to Condensed Financial Statements

(unaudited)

than 1% on net sales where the Company manufactures the Lonza Product and (iii) an annual payment in Swiss Francs in the mid-six figures per sublicense and a royalty on net sales in the low single digits where a third party manufactures the Lonza Product. These payment obligations expire ten years from the first commercial sales of the Lonza Product in such country of sale.

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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our unaudited condensed financial statements and related notes included elsewhere in this Quarterly Report on Form 10-Q and in the audited financial statements and notes thereto as of and for the year ended December 31, 2025 and the related Management’s Discussion and Analysis of Financial Condition and Results of Operations, included in our Annual Report. This discussion, particularly information with respect to our future results of operations or financial condition, business strategy and plans and objectives of management for future operations, includes forward-looking statements that involve risks and uncertainties as described under the heading “Special Note Regarding Forward-Looking Statements” in this Quarterly Report on Form 10-Q. You should review the disclosure under the heading “Risk Factors” in the Annual Report for a discussion of important factors that could cause our actual results to differ materially from those described in or implied by these forward-looking statements contained in the following discussion and analysis.

Overview

We are a clinical-stage biopharmaceutical company developing a novel disease-modifying approach targeting what we believe to be a key underlying cause of Alzheimer’s disease, or AD. Alzheimer’s disease is a progressive neurodegenerative disease of the brain that leads to loss of memory and cognitive functions and ultimately results in death. Our scientific founders pioneered research on soluble amyloid-beta oligomers, or AβOs, which are globular assemblies of the amyloid-beta, or Aβ, peptide that are distinct from Aβ monomers and amyloid plaques. Based on decades of research and supporting evidence, AβOs have gained increasing scientific acceptance as a primary toxin involved in the initiation and propagation of AD pathology. We are currently focused on advancing a targeted immunotherapy drug candidate, sabirnetug, in our Phase 2 ALTITUDE-AD clinical trial. We plan to announce top-line results in late 2026. Top-line results are expected to include the difference compared to placebo after 18 months as measured by the Integrated Alzheimer’s Disease Rating Scale, or iADRS, our primary clinical efficacy endpoint, as well as key secondary endpoints, such as Clinical Dementia Rating – Sum of the Boxes, or CDR-SB, certain safety measures such as adverse event rates, including amyloid-related imaging abnormalities, or ARIA rates, and key biomarkers. ALTITUDE-AD is a randomized, double-blind, placebo-controlled, three-arm clinical trial designed to evaluate the clinical efficacy, safety and tolerability of sabirnetug with up to 180 participants per arm for a total of 542 participants with mild cognitive impairment or mild dementia due to AD. We plan to use iADRS at 18 months as the primary outcome measure. The active doses for ALTITUDE-AD are 35 mg/kg and 50 mg/kg, dosed intravenously every four weeks. These dose levels and frequency were selected based on extensive pharmacokinetic and pharmacodynamic modeling of our Phase 1 INTERCEPT-AD clinical trial of sabirnetug. Sabirnetug is a recombinant humanized immunoglobulin gamma 2, or IgG2, monoclonal antibody, or mAb, that was designed to selectively target AβOs. In July 2023, we announced top-line results from INTERCEPT-AD, which demonstrated that sabirnetug met the primary and secondary objectives of this clinical trial in 62 participants with early AD.

We announced the results of a Phase 1 clinical trial investigating a subcutaneous dosing option of sabirnetug in March 2025. This study in healthy volunteers enrolled 16 subjects who received four weekly subcutaneous doses of 1,200 mg of sabirnetug and 12 subjects who received a single intravenous dose of 2,800 mg of sabirnetug. The most frequently reported adverse events included injection site reactions (62.5%), all of which were mild (Grade 1) in severity and resolved. No other safety issues were identified. Additionally, subcutaneous administration of sabirnetug was shown to produce sufficient systemic exposure to support further development of this formulation as a more convenient administration option for patients.

In addition, we are investigating a blood-brain barrier-penetrating, Aβ oligomer-targeted Enhanced Brain Delivery™ (EBD™) therapy for the treatment of AD. In March 2026, we announced certain preclinical data from EBD candidates, including in vitro, in vivo and non-human primate study results, supporting the advancement of the EBD program: (1) EBD candidates achieved 14-40x higher brain levels in non-human primates compared to native antibodies 24 hours after dosing; (2) hematology data in non-human primates indicated low potential for anemia, including that, at 24 hours after subcutaneous dosing, EBD candidates demonstrated no observed change in red blood cell count, hematocrit, hemoglobin or reticulocyte count; and (3) favorable stability profile and enhanced brain delivery support a path to subcutaneous administration with low-volume devices. Following this robust preclinical data from both in vitro and in vivo studies, in June 2026 we announced the nomination of two EBD development candidates, ACU301 and ACU401. Based on these developments, an investigational new drug, or IND, application for the lead candidate is targeted for mid-2027. This stems from our July 2025 entry into a collaboration, option and license agreement with JCR Pharmaceuticals Co. Ltd., or JCR, to develop an Aβ oligomer-targeted EBD therapy for the treatment of AD. Under the terms of the agreement, during the year ended December 31, 2025, we made an upfront license payment to JCR and, in June 2026, we exercised our exclusive option to develop two EBD development candidates, which required an option exercise payment of $9.25 million that was

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paid to JCR in July 2026. JCR will also be eligible to receive future milestone payments of up to $40.0 million related to development, and up to $515.0 million related to sales, for a total of up to $555.0 million, as well as single-digit percentage royalties on sales of any products that emerge from the collaboration. The combination of sabirnetug or additional, novel, AβO-selective antibodies with JCR’s blood-brain barrier-penetrating technology, J-Brain Cargo®, strengthens Acumen’s portfolio of AβO-targeted therapies. The partnership is designed to advance potential next-generation treatment options for people living with AD, by targeting the development of products with enhanced efficacy, safety and convenience.

We were incorporated in 1996 and were party to an exclusive license and research collaboration with Merck & Co., Inc., or Merck, in 2003. Although we acquired the exclusive rights to sabirnetug from Merck in 2011 following Merck’s strategic decision to focus its AD development efforts on a different product candidate, we did not recommence meaningful operations until we completed our first institutional fundraising in 2018. Since 2018, we have devoted substantially all of our efforts to organizing and staffing our company, business planning, raising capital, conducting discovery, research and development activities, and providing general and administrative support for these operations. We do not have any products approved for sale and have not generated any revenue from product sales. We have funded our operations primarily through the sale of our convertible preferred stock and common stock, the issuance of notes, entry into a term loan facility, grant revenue and, during our collaboration with Merck, certain payments received under our collaboration agreement.

In November 2023, we entered into a loan and security agreement, or the Loan Agreement, with K2 HealthVentures LLC, or, together with its affiliates, K2HV. The Loan Agreement provides us with a term loan facility in the aggregate principal amount of up to $50.0 million, of which we have borrowed $30.0 million in the first tranche and which was funded upon closing. The remaining $20.0 million is available for borrowing upon our request, subject to review by the lenders of certain information from us and discretionary approval by the lenders. The term loan facility matures on November 1, 2027 and can be extended to November 1, 2028, subject to our achievement of certain financing milestones. In accordance with the Loan Agreement, we issued to K2HV a warrant to purchase up to 730,769 shares of our common stock at an exercise price of $1.95 per share.

On March 13, 2026, we entered into a securities purchase agreement with certain institutional and accredited investors for a private placement, or the Private Placement, of 10,833,331 shares of our common stock, at an offering price of $3.30 per share. The Private Placement closed on March 16, 2026, for aggregate gross proceeds of approximately $35.7 million, before deducting offering costs of approximately $0.3 million. We intend to continue to use the net proceeds from the Private Placement to primarily support our EBD program, including ongoing preclinical development work to support the nomination of a lead clinical candidate molecule, and for working capital and other general corporate purposes.

During the six months ended June 30, 2026 and 2025, no shares of our common stock were issued under our at-the-market offering program, or the ATM. Since inception, we have issued 2,068,246 shares of our common stock under the ATM, for net proceeds of $7.9 million, or $3.84 per share.

We have incurred net losses and negative cash flows from operations since our inception. Our net losses were $53.5 million and $69.7 million for the six months ended June 30, 2026 and 2025, respectively. Approximately $44.3 million, or 83%, of the net loss for the six months ended June 30, 2026 was due to research and development spending. As of June 30, 2026, we had an accumulated deficit of $499.9 million and cash and cash equivalents and marketable securities of $110.2 million. We expect our expenses and operating losses will increase substantially for the foreseeable future as we continue clinical development activities for sabirnetug, advance our EBD program, seek to expand our product candidate portfolio through developing additional product candidates, and incur ongoing costs associated with operating as a public company. It is likely that we will seek third-party collaborators for the future commercialization of sabirnetug or any other product candidate that is approved for marketing. Should we seek to commercialize our products at our own expense, we would incur significant additional expenses for marketing, sales, manufacturing and distribution. We will not generate revenue from product sales unless and until we successfully complete clinical development and obtain regulatory approval for our product candidates.

As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy. Until we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of public or private equity offerings and debt financings or other sources, such as potential collaboration agreements, strategic alliances and licensing arrangements. We may be unable to raise additional funds or enter into such other agreements or arrangements when needed on acceptable terms, or at all. In addition, global economic conditions may impact our ability to raise additional funds, and we may be impacted by disruptions to, and volatility in, the credit and financial markets in the United States and worldwide, tariff policy and geopolitical tensions between the United States and foreign countries, rising inflation and supply disruptions, the ongoing conflicts between Russia and Ukraine, the recent

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military actions involving Iran, and the Israel-Hamas war and related sanctions, and otherwise. If these conditions persist and deepen, we could experience an inability to access additional capital, or our liquidity could otherwise be impacted. If we are unable to raise capital when needed or on attractive terms, we would be forced to delay, reduce or eliminate our research and development programs and/or future commercialization efforts. Our failure to raise capital or enter into such agreements as and when needed could have a material adverse effect on our business, results of operations and financial condition.

We evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about our ability to continue as a going concern. Based on our current operating plan, we expect that our current balance of cash and cash equivalents and marketable securities will fund our operations into early 2027, but we believe it will not be enough to fund our operations for at least 12 months from the date of issuance of our financial statements included in this Quarterly Report on Form 10-Q. Our cash forecast contains estimates and assumptions related to our ongoing clinical trial and other research and development expenses, and we cannot predict the amount or timing of all expenditures with certainty. Accordingly, we have concluded that substantial doubt exists about our ability to continue as a going concern. See “Liquidity, Capital Resources and Going Concern.”

Components of Results of Operations

Operating Expenses

Our operating expenses consist of research and development expenses and general and administrative expenses.

Research and Development Expenses

Research and development costs primarily consist of direct costs associated with consultants and materials, biologic shipping and storage, third-party contract research organizations, or CROs, and contract manufacturing organizations, or CMOs, license agreements, salaries and other personnel-related expenses. Research and development costs are expensed as incurred. More specifically, these costs include:

•costs of funding research performed by third parties that conduct research and development and nonclinical and clinical activities on our behalf;

•costs of manufacturing drug supply and drug product;

•costs of conducting nonclinical studies and clinical trials of our product candidates;

•consulting and professional fees related to research and development activities, including noncash stock-based compensation to non-employees;

•payments made pursuant to our license agreements;

•costs related to compliance with clinical regulatory requirements; and

•employee-related expenses, including salaries, benefits and noncash stock-based compensation expenses for our research and development personnel.

We do not separately track expenses by program as we currently have only one clinical-stage product candidate, sabirnetug, and our pre-clinical EBD development candidates, all of which are focused on the research and development of treatments for AD. Further, we have historically relied primarily on consultants for research and development activities; our internal research and development personnel costs currently represent approximately 21% of our total research and development expenses. Our research and development expenses increased substantially since initiating the clinical trial program for sabirnetug in 2021. We expect that our research and development expenses will increase substantially in connection with our continued clinical development activities for sabirnetug and the advancement of our EBD program.

General and Administrative Expenses

General and administrative expenses consist primarily of employee-related expenses, including noncash stock-based compensation costs, as well as business insurance, management and business consultants and other related costs. General and administrative expenses also include professional fees for legal, consulting, accounting, auditing, tax and patent services, investor and public relations, board of directors’ expenses, information technology, franchise taxes, rent, travel expenses and subscriptions.

We expect that our general and administrative expenses will remain consistent for the foreseeable future and may increase as our organization and headcount required in the future grows to support continued research and development activities

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and potential commercialization of our product candidates. These increases will likely include increased costs related to the hiring of additional personnel and fees incurred for outside consultants, attorneys and accountants, among other expenses. Additionally, we expect to continue to incur significant expenses associated with being a public company, including costs of additional personnel, accounting, audit, legal, regulatory and tax-related services associated with maintaining compliance with exchange listing and Securities and Exchange Commission, or SEC, requirements, director and officer insurance costs, and investor and public relations costs.

Other Income (Expense)

Other income (expense) includes interest income, interest expense, change in fair value of embedded derivatives and other expense, net. Interest income consists of interest income earned, as well as amortization and accretion of premiums and discounts, related to our investments in marketable securities. Interest expense includes interest due under the Loan Agreement, as well as the amortization of the related debt discount. The change in fair value of embedded derivatives relates to the embedded derivatives that were bifurcated from the term loan, borrowed under the Loan Agreement, and accounted for as a derivative at fair value which is remeasured at each reporting period for the term of the loan. Other expense, net generally consists of fees incurred on our investments in marketable securities.

Results of Operations

Comparison of the Three Months Ended June 30, 2026 and 2025

The following table summarizes our results of operations for the three months ended June 30, 2026 and 2025 (in thousands):


	Three Months Ended June 30,				Increase (Decrease)
	2026		2025		$		%
Operating expenses
Research and development	$	27,809	$	37,125	$	(9,316)	(25)	%
General and administrative	4,747		4,625		122		3	%
Total operating expenses	32,556		41,750		(9,194)		(22)	%
Loss from operations	(32,556)		(41,750)		9,194		(22)	%
Other income (expense)
Interest income	1,111		2,015		(904)		(45)	%
Interest expense	(1,094)		(1,046)		(48)		5	%
Change in fair value of embedded derivatives	(160)		(40)		(120)		*
Other expense, net	(19)		(129)		110		*
Total other (expense) income	(162)		800		(962)		(120)	%
Net loss	$	(32,718)	$	(40,950)	$	8,232	(20)	%

*Not meaningful

Research and Development Expenses

Research and development expenses were $27.8 million and $37.1 million for the three months ended June 30, 2026 and 2025, respectively. The $9.3 million decrease was primarily due to reductions of $15.2 million for manufacturing and materials costs and $3.3 million for CRO costs, which are both associated with our ALTITUDE-AD clinical trial. Additionally, we realized a decrease of $0.4 million for other research and development expenses. Partially offsetting the decreased expenses were increases of $9.3 million for license agreement expenses related to the option exercise payment owed to JCR for our exclusive option to license and develop two EBD development candidates and $0.3 million for other clinical trial expenses.

General and Administrative Expenses

General and administrative expenses were $4.7 million and $4.6 million for the three months ended June 30, 2026 and 2025, respectively. The $0.1 million increase was primarily due to increases in personnel costs of $0.2 million and legal fees of $0.1 million, partially offset by decreases for insurance expenses of $0.1 million and consulting expenses of $0.1 million.

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Other Income (Expense)

Other expense was $0.2 million for the three months ended June 30, 2026, as compared to other income of $0.8 million for the three months ended June 30, 2025. The $1.0 million decrease was primarily attributable to a $0.9 million decrease in interest income on our portfolio of marketable securities due primarily to a lower average investment balance during the three months ended June 30, 2026, with the utilization of cash from investment maturities supporting our ongoing operating cash needs. Additionally, for the three months ended June 30, 2026, there was $0.1 million of increased expense recognized with the change in fair value of our embedded derivative related to the Loan Agreement.

Comparison of the Six Months Ended June 30, 2026 and 2025

The following table summarizes our results of operations for the six months ended June 30, 2026 and 2025 (in thousands):


	Six Months Ended June 30,				Increase (Decrease)
	2026		2025		$		%
Operating expenses
Research and development	$	44,293	$	62,391	$	(18,098)	(29)	%
General and administrative	9,412		9,729		(317)		(3)	%
Total operating expenses	53,705		72,120		(18,415)		(26)	%
Loss from operations	(53,705)		(72,120)		18,415		(26)	%
Other income (expense)
Interest income	2,175		4,486		(2,311)		(52)	%
Interest expense	(2,163)		(2,069)		(94)		5	%
Change in fair value of embedded derivatives	300		150		150		*
Other expense, net	(62)		(193)		131		*
Total other income	250		2,374		(2,124)		(89)	%
Net loss	$	(53,455)	$	(69,746)	$	16,291	(23)	%

*Not meaningful

Research and Development Expenses

Research and development expenses were $44.3 million and $62.4 million for the six months ended June 30, 2026 and 2025, respectively. The $18.1 million decrease was primarily due to reductions of $21.9 million for manufacturing and materials costs and $6.7 million for CRO costs, which are both associated with our ALTITUDE-AD clinical trial. Additionally, we realized decreases of $0.6 million for other research and development expenses and $0.3 million for research and development contractors and consultants. Partially offsetting the decreased expenses were increases of $9.3 million for license agreement expenses related to the option exercise payment owed to JCR for our exclusive option to license and develop two EBD development candidates, $1.4 million for other clinical trial expenses, $0.5 million for personnel-related costs and $0.2 million for shipping and storage costs.

General and Administrative Expenses

General and administrative expenses were $9.4 million and $9.7 million for the six months ended June 30, 2026 and 2025, respectively. The $0.3 million decrease was primarily due to reductions in consulting expenses of $0.2 million, insurance expenses of $0.2 million, audit and other accounting services expenses of $0.1 million, and $0.1 million for legal fees, partially offset by an increase in personnel costs of approximately $0.3 million.

Other Income (Expense)

Other income was $0.3 million and $2.4 million for the six months ended June 30, 2026 and 2025, respectively. The $2.1 million decrease was primarily attributable to a $2.3 million decrease in interest income on our portfolio of marketable securities due primarily to a lower average investment balance during the six months ended June 30, 2026 with the utilization of cash from investment maturities supporting our ongoing operating cash needs. This decrease was partially offset by increased income of $0.2 million associated with the change in fair value of our embedded derivatives related to the Loan Agreement.

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Liquidity, Capital Resources and Going Concern

We have incurred net losses since inception. We have not generated any revenue from product sales or any other sources other than grant revenue and have incurred significant operating losses. We have not yet commercialized any products and we do not expect to generate revenue from sales of any drug candidates for at least several years, if ever.

Our operations have been financed primarily by net proceeds from the sale and issuance of our common stock and convertible preferred stock, net proceeds from our initial and subsequent public offering, the Private Placement and from sales of shares of our common stock under our ATM, borrowings under the Loan Agreement, the issuance of notes, grant revenue and, during our collaboration with Merck, which was in place from 2003 to 2011, certain payments received under our collaboration agreement.

On March 27, 2024, we filed a shelf registration statement on Form S-3, or the 2024 Registration Statement. Pursuant to the 2024 Registration Statement, we may offer and sell securities having an aggregate public offering price of up to $200.0 million. On November 13, 2025, we filed a prospectus supplement to the 2024 Registration Statement with respect to our ATM, designating up to $50.0 million of the $200.0 million of securities that may be offered pursuant to the 2024 Registration Statement for issuance under the ATM.

We have a sales agreement, or, as amended, the Sales Agreement, with BofA Securities, Inc., Stifel, Nicolaus & Company, Incorporated and BTIG, LLC as sales agents, pursuant to which we may issue and sell shares of our common stock for an aggregate offering price of up to $50.0 million under the ATM, which is included in the $200.0 million of securities that were registered for sale pursuant to a registration statement on Form S-3 filed in 2022. Pursuant to the Sales Agreement, we will pay the sales agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of our common stock. We are not obligated to make any sales of shares of our common stock under the ATM.

During the six months ended June 30, 2026 and 2025, no shares of common stock were issued under our ATM. We have issued shares of common stock for aggregate gross proceeds of $12.2 million under the ATM since the program’s inception.

On March 13, 2026, we entered into a Private Placement of 10,833,331 shares of our common stock, at an offering price of $3.30 per share. The Private Placement closed on March 16, 2026, for aggregate gross proceeds of approximately $35.7 million, before deducting offering costs of approximately $0.3 million. We intend to use the net proceeds from the Private Placement to primarily support our EBD program, including ongoing preclinical development work to support the nomination of a lead clinical candidate molecule, and for working capital and other general corporate purposes.

As of June 30, 2026, we had cash and cash equivalents and marketable securities totaling $110.2 million. Our available-for-sale marketable securities mature in less than one year. We could exhaust our available capital resources sooner than we expect, including if we decide to initiate other clinical trials or programs. We evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about our ability to continue as a going concern. Based on our current operating plan, we do not expect the current balance of our cash and cash equivalents and marketable securities will be sufficient to fund our operations for at least 12 months from the date of issuance of our unaudited condensed financial statements included in this Quarterly Report on Form 10-Q. The current balance of our cash and cash equivalents and marketable securities is expected to fund our operations into early 2027. Accordingly, management has concluded that substantial doubt exists regarding our ability to continue as a going concern.

We enter into contracts in the normal course of business with CROs and CMOs for clinical trials, nonclinical research studies and testing, manufacturing and other services and products for operating purposes. These contracts do not contain any minimum purchase commitments and are generally cancellable by us after giving a certain amount of notice. Payments due upon cancellation consist only of payments for services provided and expenses incurred up to the date of cancellation.

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Cash Flows

The following table summarizes our sources and uses of cash (in thousands):


	Six Months Ended June 30,
	2026		2025
Net cash used in operating activities	$	(42,203)	$	(65,953)
Net cash provided by investing activities	12,193		67,172
Net cash provided by (used in) financing activities	35,464		(36)
Net change in cash and cash equivalents and restricted cash	$	5,454	$	1,183

Operating Activities

The decrease in net cash used in operations of $23.8 million to $42.2 million for the six months ended June 30, 2026, from $66.0 million for the six months ended June 30, 2025, is primarily attributable to a decrease in net loss for the six months ended June 30, 2026 of $16.3 million, an increase in noncash adjustments of $0.4 million and working capital changes of $7.1 million. Significant noncash items consisted of a decrease in noncash income for amortization and accretion on marketable securities of $0.5 million and the change in fair value of embedded derivatives of $0.2 million. Working capital changes contributed $7.1 million to the reduction in cash used in operations, including a decrease in cash used for accounts payable of $16.4 million, which was partially offset by an increase in cash used for accrued expenses and other liabilities of $7.5 million, a decrease in cash provided by prepaid expenses and other current assets of $1.6 million and an increase in cash used for accrued clinical trial expenses of $0.1 million.

Investing Activities

Net cash provided by investing activities decreased by $55.0 million to $12.2 million for the six months ended June 30, 2026 from $67.2 million for the six months ended June 30, 2025. This decrease was primarily due to a decrease in proceeds from maturities and sales of marketable securities of $52.3 million and an increase in purchases of marketable securities of $2.8 million, partially offset by a $0.1 million decrease in purchases of property and equipment.

Financing Activities

Net cash provided by financing activities during the six months ended June 30, 2026 increased to $35.5 million from net cash used in financing activities of less than $0.1 million during the six months ended June 30, 2025. Cash provided by financing activities during the six months ended June 30, 2026 was primarily due to net proceeds of $35.4 million from the issuance of common stock in connection with the Private Placement and an increase of $0.1 million from the exercise of stock options, which were partially offset by an increase of $0.1 million paid for employee withholding taxes resulting from the repurchase of common shares following the vesting of RSUs.

Funding Requirements

We expect our expenses to increase in connection with our ongoing activities, particularly as we continue our research and development, conduct clinical trials and seek marketing approval for our current and any of our future product candidates. Furthermore, we expect to incur additional costs associated with operating as a public company. It is likely that we will seek third-party collaborators for the future commercialization of sabirnetug or any other product candidate that is approved for marketing. Should we seek to commercialize our products at our own expense, we would incur significant additional expenses for marketing, sales, manufacturing and distribution, which costs we may seek to offset through entry into collaboration agreements with third parties. As a result, we expect that we will need to obtain substantial additional funding in connection with our future operations. If we are unable to raise capital when needed or on acceptable terms, we could be forced to delay, reduce or eliminate our research and development programs or future commercialization efforts.

Based on our current operating plan, we believe there is substantial doubt about our ability to continue as a going concern for at least 12 months following the date of issuance of our unaudited condensed financial statements included in this Quarterly Report on Form 10-Q. We could exhaust our available capital resources sooner than we expect, including if we decide to initiate other clinical trials or programs. In addition, changing circumstances may cause us to increase our spending significantly faster than we currently anticipate, and we may need to spend more money than currently expected

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because of circumstances beyond our control. We may need to raise additional funds sooner than anticipated if we choose to expand more rapidly than we presently anticipate.

The amount and timing of our future funding requirements will depend on many factors, some of which are outside of our control, including but not limited to:

•the progress, costs, timing and results of ALTITUDE-AD and other potential clinical trials of sabirnetug, including for potential additional indications that we may pursue beyond AD;

•the requirements of the U.S. Food and Drug Administration, or the FDA, and European Medicines Agency, or EMA, and comparable foreign regulatory authorities, for clinical trials and nonclinical studies and other work, for review and approval of sabirnetug for AD;

•the outcome, costs and timing of seeking and obtaining FDA, EMA and any other regulatory approvals;

•our progress and success in investigating EBD therapy for AD;

•the number and characteristics of product candidates that we pursue;

•our ability to obtain sufficient quantities of our product candidates from our third-party manufacturers;

•our need to expand our research and development activities;

•the costs associated with securing and establishing commercialization capabilities if we were to elect to commercialize one or more products on our own;

•the economics and other terms, timing of and success of any collaboration, licensing or other arrangements into which we may enter for the commercialization of our products;

•the costs and other terms, timing and success, of acquiring, in-licensing or investing in businesses, product candidates and technologies;

•our ability to maintain, expand and defend the scope of our intellectual property portfolio, including the amount and timing of any payments we may be required to make, or that we may receive, in connection with the licensing, filing, prosecution, defense and enforcement of any patents or other intellectual property rights;

•our need and ability to retain management and hire scientific and clinical personnel;

•the effect of competing drugs and product candidates and other market developments; and

•our need to implement additional internal systems and infrastructure, including financial and reporting systems.

Additional funding may not be available to us on acceptable terms or at all. Any such funding may result in dilution to stockholders, imposition of debt covenants and repayment obligations or other restrictions that may affect our business. We also could be required to seek funds through arrangements with collaborative partners or otherwise that may require us to relinquish rights to some of our technologies or product candidates or otherwise agree to terms unfavorable to us. Any funds we raise may not be sufficient to enable us to continue to implement our long-term business strategy. Further, our ability to raise additional capital may be adversely impacted by global economic conditions and the recent disruptions to and volatility in the credit and financial markets in the United States and worldwide, as well as tariff policy and geopolitical tensions between the United States and foreign countries. Additionally, escalation in interest rates may lead financial institutions to become more selective with capital deployment and to tighten lending practices. If we are unable to raise sufficient additional capital on a timely basis, we could be forced to curtail our planned operations and the pursuit of our business strategy, which would have a material adverse effect on the value of our common stock.

Critical Accounting Policies, Significant Judgments and Use of Estimates

The preparation of financial statements in conformity with U.S. generally accepted accounting principles, or U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the unaudited condensed financial statements and the reported amounts of expenses incurred during the reporting periods. Our estimates and assumptions are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

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A description of our significant accounting policies is included in our Annual Report on Form 10-K. Please read the unaudited condensed financial statements and notes included in this Quarterly Report on Form 10-Q in conjunction with our audited financial statements and accompanying notes in our Annual Report on Form 10-K.

Our critical accounting policies that require significant judgments and estimates are more fully described under the heading “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies, Significant Judgments and Use of Estimates” in our Annual Report and in Note 2 to our audited financial statements contained in our Annual Report. There have been no significant changes to our critical accounting policies that require significant judgments and estimates from those disclosed in our Annual Report.

Emerging Growth Company and Smaller Reporting Company Status

In April 2012, the Jumpstart Our Business Startups Act of 2012, or JOBS Act, was enacted. Section 107 of the JOBS Act provides that an “emerging growth company” can take advantage of the extended transition period provided in Section 7(a)(2)(B) of the Securities Act of 1933, as amended, for complying with new or revised accounting standards. Thus, an emerging growth company can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. We elected to use the extended transition period for complying with new or revised accounting standards, which delays the adoption of these accounting standards until they would apply to private companies.

In addition, as an emerging growth company, we may take advantage of specified reduced disclosure and other requirements that are otherwise applicable generally to public companies. These provisions include:

•an exception from compliance with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002, as amended;

•reduced disclosure about our executive compensation arrangements in our periodic reports, proxy statements and registration statements;

•exemptions from the requirements of holding non-binding advisory votes on executive compensation or golden parachute arrangements; and

•an exemption from compliance with the requirements of the Public Company Accounting Oversight Board regarding the communication of critical audit matters in the auditor’s report on financial statements.

We may take advantage of these provisions until we no longer qualify as an emerging growth company. We will cease to qualify as an emerging growth company on the date that is the earliest of: (i) December 31, 2026, (ii) the last day of the fiscal year in which we have more than $1.235 billion in total annual gross revenues, (iii) the date on which we are deemed to be a “large accelerated filer” under the rules of the SEC, which means the market value of our common stock that is held by non-affiliates exceeds $700 million as of the prior June 30th or (iv) the date on which we have issued more than $1.0 billion of non-convertible debt over the prior three-year period. We may choose to take advantage of some but not all of these reduced reporting burdens. We have taken advantage of certain reduced reporting requirements in this Quarterly Report on Form 10-Q and our other filings with the SEC. Accordingly, the information contained herein may be different than you might obtain from other public companies in which you hold equity interests.

We are also a “smaller reporting company,” meaning that the market value of our shares held by non-affiliates is less than $700 million and our annual revenue was less than $100 million during the most recently completed fiscal year. We may continue to be a smaller reporting company if either (i) the market value of our shares held by non-affiliates is less than $250 million or (ii) our annual revenue is less than $100 million during the most recently completed fiscal year and the market value of our shares held by non-affiliates is less than $700 million. If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, we may choose to present only the two most recent fiscal years of audited financial statements in our Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

Item 3. Quantitative and Qualitative Disclosures About Market Risk.

Not applicable to a smaller reporting company.

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Item 4. Controls and Procedures.

Evaluation of Disclosure Controls and Procedures

We maintain “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended, or the Exchange Act, that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to our management, including our principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure.

Our management, with the participation of our principal executive officer and principal financial officer, evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of June 30, 2026. Based on the evaluation of our disclosure controls and procedures, our management concluded that, as of June 30, 2026, our disclosure controls and procedures were effective to provide reasonable assurance that the information required to be disclosed by us in this Quarterly Report on Form 10-Q was: (a) reported within the time periods specified by SEC rules and regulations, and (b) communicated to our management, including our Chief Executive Officer and Chief Financial Officer, to allow timely decisions regarding any required disclosure.

Changes in Internal Control Over Financial Reporting

There were no changes in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that occurred during the fiscal quarter ended June 30, 2026 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Inherent Limitations on Effectiveness of Internal Controls

In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable, not absolute, assurance of achieving the desired control objectives. In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints, and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs.

Our management, including our Chief Executive Officer and Chief Financial Officer, believes that our disclosure controls and procedures and internal control over financial reporting are designed to provide reasonable assurance of achieving their objectives and are effective at the reasonable assurance level. However, our management does not expect that our disclosure controls and procedures or our internal control over financial reporting will prevent all errors and all fraud.

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PART II—OTHER INFORMATION

Item 1. Legal Proceedings.

We are not subject to any material legal proceedings. From time to time, we may be involved in various claims and legal proceedings relating to claims arising out of our operations. We are not currently a party to any legal proceedings that, in the opinion of our management, are likely to have a material adverse effect on our business. Regardless of outcome, litigation can have an adverse impact on us because of defense and settlement costs, diversion of management resources and other factors.

Item 1A. Risk Factors.

Our business is subject to risks and events that, if they occur, could adversely affect our financial condition and results of operations and trading price of our securities. In addition to the other information set forth in this Quarterly Report on Form 10-Q, you should carefully consider the factors described in Part I, Item 1A. “Risk Factors” of our Annual Report on Form 10-K for the year ended December 31, 2025. There have been no material changes to the risk factors as described in our Annual Report on Form 10-K for the year ended December 31, 2025, except as follows:

We anticipate that we will no longer qualify as an “emerging growth company” as of December 31, 2026, but that we will remain a “smaller reporting company.” As a smaller reporting company, we continue to be eligible to utilize certain reduced disclosure requirements, and we cannot be certain if our use of such scaled disclosure requirements will make our common stock less attractive to investors.

As of December 31, 2026 (the last day of the fiscal year following the fifth anniversary of our initial public offering), we anticipate that we will cease to qualify as an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act of 2012, or JOBS Act. As a result, we will no longer be able to rely on certain exemptions from various reporting and governance requirements that are currently available to us, including the exemption from compliance with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act, reduced disclosure obligations regarding executive compensation and exemptions from the requirements of holding a non-binding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved.

In addition, under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards until such time as those standards apply to private companies. We elected to avail ourselves of this exemption from new or revised accounting standards and, therefore, we were not subject to the same new or revised accounting standards as other public companies during the period we were an emerging growth company. As a result, our financial statements while we were an emerging growth company may not be comparable to companies that complied with new or revised accounting pronouncements as of public company effective dates.

However, we are also a “smaller reporting company” as defined in the Exchange Act, and we anticipate that we will continue to be a smaller reporting company even after we are no longer an emerging growth company. We may continue to qualify as a smaller reporting company until the fiscal year following the determination that the worldwide market value of our voting and non-voting common stock held by non-affiliates is more than $250 million, as measured on the last business day of our second fiscal quarter, or our annual revenues are more than $100 million during the most recently completed fiscal year and our voting and non-voting common stock held by non-affiliates is more than $700 million measured on the last business day of our second fiscal quarter.

As a smaller reporting company, we are eligible to take advantage of many of the same scaled disclosures available to emerging growth companies, including scaled executive compensation disclosures and the exemption from the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act. We have elected to utilize the accommodations available to smaller reporting companies. Until we cease to be a smaller reporting company, the scaled disclosure in our SEC filings will result in less information about our company being available than for public companies that are not smaller reporting companies.

We cannot predict if investors will find our common stock less attractive because we will rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile.

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Item 2. Unregistered Sales of Equity Securities, Use of Proceeds and Issuer Purchases of Equity Securities.

(a)Recent Sales of Unregistered Equity Securities

None.

(b)Use of Proceeds

None.

(c)Issuer Purchases of Equity Securities

None.

Item 3. Defaults Upon Senior Securities.

Not applicable.

Item 4. Mine Safety Disclosures.

Not applicable.

Item 5. Other Information.

Officer and Director Trading Arrangements

From time to time, our officers (as defined in Rule 16a-1(f)) and directors may enter into Rule 10b5-1 or non-Rule 10b5-1 trading plans (as each such term is defined in Item 408 of Regulation S-K). The trading plans are intended to satisfy the affirmative defense in Rule 10b5-1(c). During the three months ended June 30, 2026, our officers and directors took the following actions with respect to 10b5-1 trading plans:

On June 29, 2026, Daniel O’Connell, our Chief Executive Officer and a member of our board of directors, entered into a Rule 10b5-1 trading plan that provides that Mr. O’Connell, acting through a broker, may sell the number of shares of common stock sufficient to cover the taxes, commissions and any fees associated with the vesting of up to 299,800 RSU awards granted to Mr. O’Connell as equity compensation, which sales may occur from January 21, 2027 to December 31, 2029. On June 30, 2026, Mr.O’Connell also entered into a separate Rule 10b5-1 trading plan that provides that Mr. O’Connell, acting through a broker, may sell (1) 294,858 shares of our common stock and (2) 418,903 shares of our common stock received upon the exercise of option awards granted to Mr.O’Connell as equity incentive compensation, which sales may occur from September 29, 2026 to June 30, 2027.

On June 29, 2026, Matthew Zuga, our Chief Financial Officer and Chief Business Officer, entered into a Rule 10b5-1 trading plan that provides that Mr. Zuga, acting through a broker, may sell the number of shares of common stock sufficient to cover the taxes, commissions and any fees associated with the vesting of up to 99,133 RSU awards granted to Mr. Zuga as equity incentive compensation, which sales may occur from January 19, 2027 to December 31, 2029. On June 29, 2026, Mr. Zuga also entered into a separate Rule 10b5-1 plan that provides that Mr. Zuga, acting through a broker, may sell 616,591 shares of our common stock received upon the exercise of option awards granted to Mr. Zuga as equity incentive compensation, which sales may occur from September 28, 2026 to September 28, 2027.

On June 30, 2026, Amy Schacterle, Ph.D., our Chief Regulatory Officer and Head of Quality, entered into a Rule 10b5-1 trading plan that provides that Dr. Schacterle, acting through a broker, may sell 147,500 shares of our common stock received upon the exercise of option awards and 31,133 shares of our common stock received upon the settlement of RSU awards granted to Dr. Schacterle as equity incentive compensation, which sales may occur from October 1, 2026 to December 31, 2027. On June 30, 2026, Dr. Schacterle also entered into a separate Rule 10b5-1 plan that provides that Dr. Schacterle, acting through a broker, may sell the number of shares of common stock sufficient to cover the taxes, commissions and any fees associated with the vesting of up to 84,600 RSU awards granted to Dr. Schacterle as equity incentive compensation, which sales may occur from January 19, 2027 to December 31, 2029.

Approval of Amended and Restated 2021 Plan

On June 3, 2026, the Company’s stockholders approved the adoption of the Company’s Amended and Restated 2021 Equity Incentive Plan (the “Amended and Restated 2021 Plan”) to (i) increase the number of shares available for issuance under the Company’s 2021 Equity Incentive Plan (the “2021 Plan”) by 10,000,000 shares, (ii) remove the automatic

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“evergreen” share pool increase provision from the 2021 Plan, and (iii) prohibit repricing of stock options without stockholder approval (other than in connection with certain corporate transactions). This disclosure is qualified in its entirety by reference to the Amended and Restated 2021 Plan, which is filed as Exhibit 10.1 to this Form 10-Q.

Item 6. Exhibits.


Exhibit Number						Description of Exhibit

3.1						Amended and Restated Certificate of Incorporation (incorporated by reference to Exhibit 3.1 to the Company’s Current Report on Form 8-K (File No. 001-40551), filed with the Securities and Exchange Commission on June 8, 2023).

3.2						Amended and Restated Bylaws (incorporated by reference to Exhibit 3.1 to the Company’s Current Report on Form 8-K (File No. 001-40551), filed with the Securities and Exchange Commission on March 15, 2023).

10.1*+						Acumen Pharmaceuticals, Inc. Amended and Restated 2021 Equity Incentive Plan and Forms of Stock Option Grant Notice, Award Agreement and Notice of Exercise and RSU Grant Notice and Award Agreement.

31.1*						Certification of Principal Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

31.2*						Certification of Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

32.1#						Certification of Principal Executive Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

32.2#						Certification of Principal Financial Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

101.INS*						Inline XBRL Instance Document—the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document

101.SCH*						Inline XBRL Taxonomy Extension Schema Document

101.CAL*						Inline XBRL Taxonomy Extension Calculation Linkbase Document

101.DEF*						Inline XBRL Taxonomy Extension Definition Linkbase Document

101.LAB*						Inline XBRL Taxonomy Extension Label Linkbase Document

101.PRE*						Inline XBRL Taxonomy Extension Presentation Linkbase Document

104						Cover Page Interactive Data File (embedded within the Inline XBRL document)

* Filed herewith

+ Indicates management contract or compensatory plan.

# These certifications are being furnished solely to accompany this quarterly report pursuant to 18 U.S.C. Section 1350, and are not being filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, and are not to be incorporated by reference into any filing of the registrant, whether made before or after the date hereof, regardless of any general incorporation language in such filing.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.


	ACUMEN PHARMACEUTICALS, INC.

Date: August 12, 2026	By:	/s/ Daniel O’Connell
		Daniel O’Connell
		Chief Executive Officer (Principal Executive Officer)

Date: August 12, 2026	By:	/s/ Matthew Zuga
		Matthew Zuga
		Chief Financial Officer and Chief Business Officer (Principal Financial and Accounting Officer)

Document

Acumen Pharmaceuticals, Inc.
Amended and Restated 2021 Equity Incentive Plan

Adopted by the Board of Directors: April 21, 2026
Approved by the Stockholders: June 3, 2026

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Page


1. General.			1
2. Shares Subject to the Plan.			1
3. Eligibility and Limitations.			2
4. Options and Stock Appreciation Rights.			2
5. Awards Other Than Options and Stock Appreciation Rights.			5
6. Adjustments upon Changes in Common Stock; Other Corporate Events.			6
7. Administration.			8
8. Tax Withholding			9
9. Miscellaneous.			10
10. Covenants of the Company.			12
11. Additional Rules for Awards Subject to Section 409A.			12
12. Severability.			15
13. Termination of the Plan.			15
14. Definitions.			15

-i-

1.General.

(a)Successor to and Continuation of Prior Plan. The Plan is the successor to and continuation of the Prior Plan. As of the Effective Date, (i) no additional awards may be granted under the Prior Plan; (ii) any Returning Shares from the Prior Plan will become available for issuance pursuant to Awards granted under this Plan; and (iii) all outstanding awards granted under the Prior Plan will remain subject to the terms of the Prior Plan (except to the extent such outstanding awards result in Returning Shares that become available for issuance pursuant to Awards granted under this Plan). All Awards granted under this Plan will be subject to the terms of this Plan.

(b)Plan Purpose. The Company, by means of the Plan, seeks to secure and retain the services of Employees, Directors and Consultants, to provide incentives for such persons to exert maximum efforts for the success of the Company and any Affiliate and to provide a means by which such persons may be given an opportunity to benefit from increases in value of the Common Stock through the granting of Awards.

(c)Available Awards. The Plan provides for the grant of the following Awards: (i) Incentive Stock Options; (ii) Nonstatutory Stock Options; (iii) SARs; (iv) Restricted Stock Awards; (v) RSU Awards; (vi) Performance Awards; and (vii) Other Awards.

(d)Effective Date. The Plan’s terms will become effective on the Effective Date.

2.Shares Subject to the Plan.

(a)Share Reserve. Subject to adjustment in accordance with Section 2(c) and any adjustments as necessary to implement any Capitalization Adjustments, the aggregate number of shares of Common Stock that may be issued pursuant to Awards will not exceed the sum of: (i) 10,000,000 shares, plus (ii) the Available Reserve (not to exceed 1,433,852 shares), plus (iii) the number of Returning Shares, if any, as such shares become available from time to time (not to exceed 19,040,630 shares minus the Available Reserve).

(b)Aggregate Incentive Stock Option Limit. Notwithstanding anything to the contrary in Section 2(a) and subject to any adjustments as necessary to implement any Capitalization Adjustments, the aggregate maximum number of shares of Common Stock that may be issued pursuant to the exercise of Incentive Stock Options is 29,040,630 shares.

(c)Share Reserve Operation.

(i)Limit Applies to Common Stock Issued Pursuant to Awards. For clarity, the Share Reserve is a limit on the number of shares of Common Stock that may be issued pursuant to Awards and does not limit the granting of Awards, except that the Company will keep available at all times the number of shares of Common Stock reasonably required to satisfy its obligations to issue shares pursuant to such Awards. Shares may be issued in connection with a merger or acquisition as permitted by, as applicable, Nasdaq Listing Rule 5635(c), NYSE Listed Company Manual Section 303A.08, NYSE American Company Guide Section 711 or other applicable rule, and such issuance will not reduce the number of shares available for issuance under the Plan.

(ii)Actions that Do Not Constitute Issuance of Common Stock and Do Not Reduce Share Reserve. The following actions do not result in an issuance of shares under the Plan and accordingly do not reduce the number of shares subject to the Share Reserve and available for issuance under the Plan: (1) the expiration or termination of any portion of an Award without the shares covered by such portion of the Award having been issued; (2) the settlement of any portion of an Award in cash (i.e., the Participant receives cash rather than Common Stock); (3) the withholding of shares that would otherwise be issued by the Company to satisfy the exercise, strike or purchase price of an Award; or (4) the withholding of shares that would otherwise be issued by the Company to satisfy a tax withholding obligation in connection with an Award.

(iii)Reversion of Previously Issued Shares of Common Stock to Share Reserve. The following shares of Common Stock previously issued pursuant to an Award and accordingly initially deducted from the Share Reserve will be added back to the Share Reserve and again become available for issuance under the Plan: any shares that are forfeited back to or repurchased by the Company because of a failure to meet a contingency or condition required for the vesting of such shares; (2) any shares that are reacquired by the Company to satisfy the exercise, strike or purchase price of an Award; and (3) any shares that are reacquired by the Company to satisfy a tax withholding obligation in connection with an Award.

3.Eligibility and Limitations.

(a)Eligible Award Recipients. Subject to the terms of the Plan, Employees, Directors and Consultants are eligible to receive Awards.

(b)Specific Award Limitations.

(i)Limitations on All Awards. No term of an Award shall provide for automatic “reload” grants of additional Awards upon the exercise of an Option or SAR.

(ii)Limitations on Incentive Stock Option Recipients. Incentive Stock Options may be granted only to Employees of the Company or a “parent corporation” or “subsidiary corporation” thereof (as such terms are defined in Sections 424(e) and (f) of the Code).

(iii)Incentive Stock Option $100,000 Limitation. To the extent that the aggregate Fair Market Value (determined at the time of grant) of Common Stock with respect to which Incentive Stock Options are exercisable for the first time by any Optionholder during any calendar year (under all plans of the Company and any Affiliates) exceeds $ 100,000 (or such other limit established in the Code) or otherwise does not comply with the rules governing Incentive Stock Options, the Options or portions thereof that exceed such limit (according to the order in which they were granted) or otherwise do not comply with such rules will be treated as Nonstatutory Stock Options, notwithstanding any contrary provision of the applicable Option Agreement(s).

(iv)Limitations on Incentive Stock Options Granted to Ten Percent Stockholders. A Ten Percent Stockholder may not be granted an Incentive Stock Option unless (i) the exercise price of such Option is at least 110% of the Fair Market Value on the date of grant of such Option and (ii) the Option is not exercisable after the expiration of five years from the date of grant of such Option.

(v)Limitations on Nonstatutory Stock Options and SARs. Nonstatutory Stock Options and SARs may not be granted to Employees, Directors and Consultants who are providing Continuous Service only to any “parent” of the Company (as such term is defined in Rule 405) unless the stock underlying such Awards is treated as “service recipient stock” under Section 409A because the Awards are granted pursuant to a corporate transaction (such as a spin off transaction) or unless such Awards otherwise comply with the distribution requirements of Section 409A.

(c)Aggregate Incentive Stock Option Limit. The aggregate maximum number of shares of Common Stock that may be issued pursuant to the exercise of Incentive Stock Options is the number of shares specified in Section 2(b).

(d)Non-Employee Director Compensation Limit. The aggregate value of all compensation granted or paid, as applicable, to any individual for service as a Non-Employee Director with respect to any period commencing on the date of the Company’s Annual Meeting of Stockholders for a particular year and ending on the day immediately prior to the date of the Company’s Annual Meeting of Stockholders for the next subsequent year (the “Annual Period”), including Awards granted and cash fees paid by the Company to such Non-Employee Director, will not exceed (i) $750,000 in total value or (ii) in the event such Non-Employee Director is first appointed or elected to the Board during such Annual Period, $1,000,000 in total value, in each case calculating the value of any equity awards based on the grant date fair value of such equity awards for financial reporting purposes. The limitations in this Section 3(d) shall not apply to any compensation received other than in respect of an individual’s service as a Non-Employee Director (for example, service as an advisor or consultant).

4.Options and Stock Appreciation Rights.

Each Option and SAR will have such terms and conditions as determined by the Board. Each Option will be designated in writing as an Incentive Stock Option or Nonstatutory Stock Option at the time of grant; provided, however, that if an Option is not so designated, then such Option will be a Nonstatutory Stock Option, and the shares purchased upon exercise of each type of Option will be separately accounted for. Each SAR will be denominated in shares of Common Stock equivalents. The terms and conditions of separate Options and SARs need not be identical; provided, however, that each Option Agreement and SAR Agreement will conform (through incorporation of provisions hereof by reference in the Award Agreement or otherwise) to the substance of each of the following provisions:

(a)Term. Subject to Section 3(b) regarding Ten Percent Stockholders, no Option or SAR will be exercisable after the expiration of ten years from the date of grant of such Award or such shorter period specified in the Award Agreement.

(b)Exercise or Strike Price. Subject to Section 3(b) regarding Ten Percent Stockholders, the exercise or strike price of each Option or SAR will not be less than 100% of the Fair Market Value on the date of grant of such Award. Notwithstanding the foregoing, an Option or SAR may be granted with an exercise or strike price lower than 100% of the Fair Market Value on the date of grant of such Award if such Award is granted pursuant to an assumption of or substitution for another option or stock appreciation right pursuant to a Corporate Transaction and in a manner consistent with the provisions of Sections 409A and, if applicable, 424(a) of the Code.

(c)Exercise Procedure and Payment of Exercise Price for Options. In order to exercise an Option, the Participant must provide notice of exercise to the Plan Administrator in accordance with the procedures specified in the Option Agreement or otherwise provided by the Company. The Board has the authority to grant Options that do not permit all of the following methods of payment (or otherwise restrict the ability to use certain methods) and to grant Options that require the consent of the Company to utilize a particular method of payment. The exercise price of an Option may be paid, to the extent permitted by Applicable Law and as determined by the Board, by one or more of the following methods of payment to the extent set forth in the Option Agreement:

(i)by cash or check, bank draft or money order payable to the Company;

(ii)pursuant to a “cashless exercise” program developed under Regulation T as promulgated by the Federal Reserve Board that, prior to the issuance of the Common Stock subject to the Option, results in either the receipt of cash (or check) by the Company or the receipt of irrevocable instructions to pay the exercise price to the Company from the sales proceeds;

(iii)by delivery to the Company (either by actual delivery or attestation) of shares of Common Stock that are already owned by the Participant free and clear of any liens, claims, encumbrances or security interests, with a Fair Market Value on the date of exercise that does not exceed the exercise price, provided that (1) at the time of exercise the Common Stock is publicly traded, (2) any remaining balance of the exercise price not satisfied by such delivery is paid by the Participant in cash or other permitted form of payment, (3) such delivery would not violate any Applicable Law or agreement restricting the redemption of the Common Stock, (4) any certificated shares are endorsed or accompanied by an executed assignment separate from certificate, and (5) such shares have been held by the Participant for any minimum period necessary to avoid adverse accounting treatment as a result of such delivery;

(iv)if the Option is a Nonstatutory Stock Option, by a “net exercise” arrangement pursuant to which the Company will reduce the number of shares of Common Stock issuable upon exercise by the largest whole number of shares with a Fair Market Value on the date of exercise that does not exceed the exercise price, provided that (1) such shares used to pay the exercise price will not be exercisable thereafter and (2) any remaining balance of the exercise price not satisfied by such net exercise is paid by the Participant in cash or other permitted form of payment; or

(v)in any other form of consideration that may be acceptable to the Board and permissible under Applicable Law.

(d)Exercise Procedure and Payment of Appreciation Distribution for SARs. In order to exercise any SAR, the Participant must provide notice of exercise to the Plan Administrator in accordance with the SAR Agreement. The appreciation distribution payable to a Participant upon the exercise of a SAR will not be greater than an amount equal to the excess of (i) the aggregate Fair Market Value on the date of exercise of a number of shares of Common Stock equal to the number of Common Stock equivalents that are vested and being exercised under such SAR, over (ii) the strike price of such SAR. Such appreciation distribution may be paid to the Participant in the form of Common Stock or cash (or any combination of Common Stock and cash) or in any other form of payment, as determined by the Board and specified in the SAR Agreement.

(e)Transferability. Options and SARs may not be transferred to third party financial institutions for value. The Board may impose such additional limitations on the transferability of an Option or SAR as it determines. In the absence of any such determination by the Board, the following restrictions on the transferability of Options and SARs will apply, provided that except as explicitly provided herein, neither an Option nor a SAR may be transferred for consideration and provided, further, that if an Option is an Incentive Stock Option, such Option may be deemed to be a Nonstatutory Stock Option as a result of such transfer:

(i)Restrictions on Transfer. An Option or SAR will not be transferable, except by will or by the laws of descent and distribution, and will be exercisable during the lifetime of the Participant only by the Participant; provided, however, that the Board may permit transfer of an Option or SAR in a manner that is not prohibited by applicable tax and securities laws upon the Participant’s request, including to a trust if the Participant is considered to be the sole beneficial owner of such trust (as determined under Section 671 of the Code and applicable state law) while such Option or SAR is held in such trust, provided that the Participant and the trustee enter into a transfer and other agreements required by the Company.

(ii)Domestic Relations Orders. Notwithstanding the foregoing, subject to the execution of transfer documentation in a format acceptable to the Company and subject to the approval of the Board or a duly authorized Officer, an Option or SAR may be transferred pursuant to a domestic relations order.

(f)Vesting. The Board may impose such restrictions on or conditions to the vesting and/or exercisability of an Option or SAR as determined by the Board. Except as otherwise provided in the Award Agreement or other written agreement between a Participant and the Company or an Affiliate, vesting of Options and SARs will cease upon termination of the Participant’s Continuous Service.

(g)Termination of Continuous Service for Cause. Except as explicitly otherwise provided in the Award Agreement or other written agreement between a Participant and the Company or an Affiliate, if a Participant’s Continuous Service is terminated for Cause, the Participant’s Options and SARs will terminate and be forfeited immediately upon such termination of Continuous Service, and the Participant will be prohibited from exercising any portion (including any vested portion) of such Awards on and after the date of such termination of Continuous Service and the Participant will have no further right, title or interest in such forfeited Award, the shares of Common Stock subject to the forfeited Award, or any consideration in respect of the forfeited Award.

(h)Post-Termination Exercise Period Following Termination of Continuous Service for Reasons Other than Cause. Subject to Section 4(i), if a Participant’s Continuous Service terminates for any reason other than for Cause, the Participant may exercise his or her Option or SAR to the extent vested, but only within the following period of time or, if applicable, such other period of time provided in the Award Agreement or other written agreement between a Participant and the Company or an Affiliate; provided, however, that in no event may such Award be exercised after the expiration of its maximum term (as set forth in Section 4(a)):

(i)three months following the date of such termination if such termination is a termination without Cause (other than any termination due to the Participant’s Disability or death);

(ii)12 months following the date of such termination if such termination is due to the Participant’s Disability;

(iii)18 months following the date of such termination if such termination is due to the Participant’s death; or

(iv)18 months following the date of the Participant’s death if such death occurs following the date of such termination but during the period such Award is otherwise exercisable (as provided in (i) or (ii) above).

Following the date of such termination, to the extent the Participant does not exercise such Award within the applicable Post-Termination Exercise Period (or, if earlier, prior to the expiration of the maximum term of such Award), such unexercised portion of the Award will terminate, and the Participant will have no further right, title or interest in the terminated Award, the shares of Common Stock subject to the terminated Award, or any consideration in respect of the terminated Award.

(i)Restrictions on Exercise; Extension of Exercisability. A Participant may not exercise an Option or SAR at any time that the issuance of shares of Common Stock upon such exercise would violate Applicable Law. Except as otherwise provided in the Award Agreement or other written agreement between a Participant and the Company or an Affiliate, if a Participant’s Continuous Service terminates for any reason other than for Cause and, at any time during the last thirty days of the applicable Post-Termination Exercise Period: (i) the exercise of the Participant’s Option or SAR would be prohibited solely because the issuance of shares of Common Stock upon such exercise would violate Applicable Law, or (ii) the immediate sale of any shares of Common Stock issued upon such exercise would violate the Company’s Trading Policy, then the applicable Post-Termination Exercise Period will be extended to the last day of the calendar month that commences following the date the Award would otherwise expire, with an additional extension of the exercise period to the last day of the next calendar month to apply if any of the foregoing restrictions apply at any time during such extended exercise period (generally without limitation as

to the maximum permitted number of extensions); provided, however, that in no event may such Award be exercised after the expiration of its maximum term (as set forth in Section 4(a)).

(j)Non-Exempt Employees. No Option or SAR, whether or not vested, granted to an Employee who is a non-exempt employee for purposes of the Fair Labor Standards Act of 1938, as amended, will be first exercisable for any shares of Common Stock until at least six months following the date of grant of such Award. Notwithstanding the foregoing, in accordance with the provisions of the Worker Economic Opportunity Act, any vested portion of such Award may be exercised earlier than six months following the date of grant of such Award in the event of (i) such Participant’s death or Disability, (ii) a Corporate Transaction in which such Award is not assumed, continued or substituted, (iii) a Change in Control, or (iv) such Participant’s retirement (as such term may be defined in the Award Agreement or another applicable agreement or, in the absence of any such definition, in accordance with the Company’s then current employment policies and guidelines). This Section 4(j) is intended to operate so that any income derived by a non-exempt employee in connection with the exercise or vesting of an Option or SAR will be exempt from his or her regular rate of pay.

(k)Whole Shares. Options and SARs may be exercised only with respect to whole shares of Common Stock or their equivalents.

(l)No Repricing. Other than in connection with a Capitalization Adjustment, Corporate Transaction, or as otherwise contemplated by Section 6 below, the Board may not, without obtaining stockholder approval, effect: (1) the reduction of the exercise price (or strike price) of any outstanding Option or SAR; (2) the cancellation of any outstanding Option or SAR and the grant in substitution therefor of (A) a new Option, SAR, Restricted Stock Award, RSU Award or Other Award, under the Plan or another equity plan of the Company, covering the same or a different number of shares of Common Stock, (B) cash and/or (C) other valuable consideration (as determined by the Board); or (3) any other action that is treated as a repricing under generally accepted accounting principles.

5.Awards Other Than Options and Stock Appreciation Rights.

(a)Restricted Stock Awards and RSU Awards. Each Restricted Stock Award and RSU Award will have such terms and conditions as determined by the Board; provided, however, that each Restricted Stock Award Agreement and RSU Award Agreement will conform (through incorporation of the provisions hereof by reference in the Award Agreement or otherwise) to the substance of each of the following provisions:

(i)Form of Award.

(1)RSAs: To the extent consistent with the Company’s Bylaws, at the Board’s election, shares of Common Stock subject to a Restricted Stock Award may be (i) held in book entry form subject to the Company’s instructions until such shares become vested or any other restrictions lapse, or (ii) evidenced by a certificate, which certificate will be held in such form and manner as determined by the Board. Unless otherwise determined by the Board, a Participant will have voting and other rights as a stockholder of the Company with respect to any shares subject to a Restricted Stock Award.

(2)RSUs: An RSU Award represents a Participant’s right to be issued on a future date the number of shares of Common Stock that is equal to the number of restricted stock units subject to the RSU Award. As a holder of an RSU Award, a Participant is an unsecured creditor of the Company with respect to the Company’s unfunded obligation, if any, to issue shares of Common Stock in settlement of such Award and nothing contained in the Plan or any RSU Award Agreement, and no action taken pursuant to its provisions, will create or be construed to create a trust of any kind or a fiduciary relationship between a Participant and the Company or an Affiliate or any other person. A Participant will not have voting or any other rights as a stockholder of the Company with respect to any RSU Award (unless and until shares are actually issued in settlement of a vested RSU Award).

(ii)Consideration.

(1)RSA: A Restricted Stock Award may be granted in consideration for (A) cash or check, bank draft or money order payable to the Company, (B) past services to the Company or an Affiliate, or (C) any other form of consideration (including future services) as the Board may determine and permissible under Applicable Law.

(2)RSU: Unless otherwise determined by the Board at the time of grant, an RSU Award will be granted in consideration for the Participant’s services to the Company or an Affiliate, such that the Participant will not be required to make any payment to the Company (other than such services) with respect to the grant or vesting of the RSU Award, or the issuance of any shares of Common Stock pursuant to the RSU Award. If,

at the time of grant, the Board determines that any consideration must be paid by the Participant (in a form other than the Participant’s services to the Company or an Affiliate) upon the issuance of any shares of Common Stock in settlement of the RSU Award, such consideration may be paid in any form of consideration as the Board may determine and permissible under Applicable Law.

(iii)Vesting. The Board may impose such restrictions on or conditions to the vesting of a Restricted Stock Award or RSU Award as determined by the Board. Except as otherwise provided in the Award Agreement or other written agreement between a Participant and the Company or an Affiliate, vesting of Restricted Stock Awards and RSU Awards will cease upon termination of the Participant’s Continuous Service.

(iv)Termination of Continuous Service. Except as otherwise provided in the Award Agreement or other written agreement between a Participant and the Company or an Affiliate, if a Participant’s Continuous Service terminates for any reason, (i) the Company may receive through a forfeiture condition or a repurchase right any or all of the shares of Common Stock held by the Participant under his or her Restricted Stock Award that have not vested as of the date of such termination as set forth in the Restricted Stock Award Agreement and (ii) any portion of his or her RSU Award that has not vested will be forfeited upon such termination and the Participant will have no further right, title or interest in the RSU Award, the shares of Common Stock issuable pursuant to the RSU Award, or any consideration in respect of the RSU Award.

(v)Dividends and Dividend Equivalents. Dividends or dividend equivalents may be paid or credited, as applicable, with respect to any shares of Common Stock subject to a Restricted Stock Award or RSU Award, as determined by the Board and specified in the Award Agreement; provided, however, that dividends or dividend equivalents relating to an Award that, at the dividend payment date, remains subject to a risk of forfeiture (whether service-based or performance-based) shall be subject to the same risk of forfeiture as applies to the underlying Award and in no event shall such dividends or dividend equivalents be paid unless and until such Award vests and becomes payable. Any entitlement to dividend equivalents or similar entitlements will be established and administered either consistent with an exemption from, or in compliance with, the applicable requirements of Section 409A.

(vi)Settlement of RSU Awards. An RSU Award may be settled by the issuance of shares of Common Stock or cash (or any combination thereof) or in any other form of payment, as determined by the Board and specified in the RSU Award Agreement. At the time of grant, the Board may determine to impose such restrictions or conditions that delay such delivery to a date following the vesting of the RSU Award.

(b)Performance Awards. With respect to any Performance Award, the length of any Performance Period, the Performance Goals to be achieved during the Performance Period, the other terms and conditions of such Award, and the measure of whether and to what degree such Performance Goals have been attained will be determined by the Board.

(c)Other Awards. Other forms of Awards valued in whole or in part by reference to, or otherwise based on, Common Stock, including the appreciation in value thereof (e.g., options or stock rights with an exercise price or strike price less than 100% of the Fair Market Value at the time of grant) may be granted either alone or in addition to Awards provided for under Section 4 and the preceding provisions of this Section 5. Subject to the provisions of the Plan, the Board will have sole and complete discretion to determine the persons to whom and the time or times at which such Other Awards will be granted, the number of shares of Common Stock (or the cash equivalent thereof) to be granted pursuant to such Other Awards and all other terms and conditions of such Other Awards.

6.Adjustments upon Changes in Common Stock; Other Corporate Events.

(a)Capitalization Adjustments. In the event of a Capitalization Adjustment, the Board shall appropriately and proportionately adjust: (i) the class(es) and maximum number of shares of Common Stock subject to the Plan; (ii) the class(es) and maximum number of shares that may be issued pursuant to the exercise of Incentive Stock Options pursuant to Section 2(b); and (iii) the class(es) and number of securities and exercise price, strike price or purchase price of Common Stock subject to outstanding Awards. The Board shall make such adjustments, and its determination shall be final, binding and conclusive. Notwithstanding the foregoing, no fractional shares or rights for fractional shares of Common Stock shall be created in order to implement any Capitalization Adjustment. The Board shall determine an appropriate equivalent benefit, if any, for any fractional shares or rights to fractional shares that might be created by the adjustments referred to in the preceding provisions of this Section.

(b)Dissolution or Liquidation. Except as otherwise provided in the Award Agreement, in the event of a dissolution or liquidation of the Company, all outstanding Awards (other than Awards consisting of vested and outstanding shares of Common Stock not subject to a forfeiture condition or the Company’s right of repurchase) will

terminate immediately prior to the completion of such dissolution or liquidation, and the shares of Common Stock subject to the Company’s repurchase rights or subject to a forfeiture condition may be repurchased or reacquired by the Company notwithstanding the fact that the holder of such Award is providing Continuous Service, provided, however, that the Board may determine to cause some or all Awards to become fully vested, exercisable and/or no longer subject to repurchase or forfeiture (to the extent such Awards have not previously expired or terminated) before the dissolution or liquidation is completed but contingent on its completion.

(c)Corporate Transaction. The following provisions will apply to Awards in the event of a Corporate Transaction unless otherwise provided in the instrument evidencing the Award or any other written agreement between the Company or any Affiliate and the Participant or unless otherwise expressly provided by the Board at the time of grant of an Award.

(i)Awards May Be Assumed. In the event of a Corporate Transaction, any surviving corporation or acquiring corporation (or the surviving or acquiring corporation’s parent company) may assume or continue any or all Awards outstanding under the Plan or may substitute similar awards for Awards outstanding under the Plan (including but not limited to, awards to acquire the same consideration paid to the stockholders of the Company pursuant to the Corporate Transaction), and any reacquisition or repurchase rights held by the Company in respect of Common Stock issued pursuant to Awards may be assigned by the Company to the successor of the Company (or the successor’s parent company, if any), in connection with such Corporate Transaction. A surviving corporation or acquiring corporation (or its parent) may choose to assume or continue only a portion of an Award or substitute a similar award for only a portion of an Award, or may choose to assume or continue the Awards held by some, but not all Participants. The terms of any assumption, continuation or substitution will be set by the Board.

(ii)Awards Held by Current Participants. In the event of a Corporate Transaction in which the surviving corporation or acquiring corporation (or its parent company) does not assume or continue such outstanding Awards or substitute similar awards for such outstanding Awards, then with respect to Awards that have not been assumed, continued or substituted and that are held by Participants whose Continuous Service has not terminated prior to the effective time of the Corporate Transaction (referred to as the “Current Participants”), the vesting of such Awards (and, with respect to Options and Stock Appreciation Rights, the time when such Awards may be exercised) will be accelerated in full to a date prior to the effective time of such Corporate Transaction (contingent upon the effectiveness of the Corporate Transaction) as the Board determines (or, if the Board does not determine such a date, to the date that is five (5) days prior to the effective time of the Corporate Transaction), and such Awards will terminate if not exercised (if applicable) at or prior to the effective time of the Corporate Transaction, and any reacquisition or repurchase rights held by the Company with respect to such Awards will lapse (contingent upon the effectiveness of the Corporate Transaction). With respect to the vesting of Performance Awards that will accelerate upon the occurrence of a Corporate Transaction pursuant to this subsection (ii) and that have multiple vesting levels depending on the level of performance, unless otherwise provided in the Award Agreement or unless otherwise provided by the Board, the vesting of such Performance Awards will accelerate at 100% of the target level upon the occurrence of the Corporate Transaction in which the Awards are not assumed in accordance with Section 6(c)(i). With respect to the vesting of Awards that will accelerate upon the occurrence of a Corporate Transaction pursuant to this subsection (ii) and are settled in the form of a cash payment, such cash payment will be made no later than 30 days following the occurrence of the Corporate Transaction or such later date as required by Section 409A of the Code.

(iii)Awards Held by Persons other than Current Participants. In the event of a Corporate Transaction in which the surviving corporation or acquiring corporation (or its parent company) does not assume or continue such outstanding Awards or substitute similar awards for such outstanding Awards, then with respect to Awards that have not been assumed, continued or substituted and that are held by persons other than Current Participants, such Awards will terminate if not exercised (if applicable) prior to the occurrence of the Corporate Transaction; provided, however, that any reacquisition or repurchase rights held by the Company with respect to such Awards will not terminate and may continue to be exercised notwithstanding the Corporate Transaction.

(iv)Payment for Awards in Lieu of Exercise. Notwithstanding the foregoing, in the event an Award will terminate if not exercised prior to the effective time of a Corporate Transaction, the Board may provide, in its sole discretion, that the holder of such Award may not exercise such Award but will receive a payment, in such form as may be determined by the Board, equal in value, at the effective time, to the excess, if any, of (1) the value of the property the Participant would have received upon the exercise of the Award (including, at the discretion of the Board, any unvested portion of such Award), over (2) any exercise price payable by such holder in connection with such exercise.

(d)Appointment of Stockholder Representative. As a condition to the receipt of an Award under this Plan, a Participant will be deemed to have agreed that the Award will be subject to the terms of any agreement governing a Corporate Transaction involving the Company, including, without limitation, a provision for the

appointment of a stockholder representative that is authorized to act on the Participant’s behalf with respect to any escrow, indemnities and any contingent consideration.

(e)No Restriction on Right to Undertake Transactions. The grant of any Award under the Plan and the issuance of shares pursuant to any Award does not affect or restrict in any way the right or power of the Company or the stockholders of the Company to make or authorize any adjustment, recapitalization, reorganization or other change in the Company’s capital structure or its business, any merger or consolidation of the Company, any issue of stock or of options, rights or options to purchase stock or of bonds, debentures, preferred or prior preference stocks whose rights are superior to or affect the Common Stock or the rights thereof or which are convertible into or exchangeable for Common Stock, or the dissolution or liquidation of the Company, or any sale or transfer of all or any part of its assets or business, or any other corporate act or proceeding, whether of a similar character or otherwise.

7.Administration.

(a)Administration by Board. The Board will administer the Plan unless and until the Board delegates administration of the Plan to a Committee or Committees, as provided in subsection (c) below.

(b)Powers of Board. The Board will have the power, subject to, and within the limitations of, the express provisions of the Plan:

(i)To determine from time to time (1) which of the persons eligible under the Plan will be granted Awards; (2) when and how each Award will be granted; (3) what type or combination of types of Award will be granted; (4) the provisions of each Award granted (which need not be identical), including the time or times when a person will be permitted to receive an issuance of Common Stock or other payment pursuant to an Award; (5) the number of shares of Common Stock or cash equivalent with respect to which an Award will be granted to each such person; (6) the Fair Market Value applicable to an Award; and (7) the terms of any Performance Award that is not valued in whole or in part by reference to, or otherwise based on, the Common Stock, including the amount of cash payment or other property that may be earned and the timing of payment.

(ii)To construe and interpret the Plan and Awards granted under it, and to establish, amend and revoke rules and regulations for its administration. The Board, in the exercise of this power, may correct any defect, omission or inconsistency in the Plan or in any Award Agreement, in a manner and to the extent it deems necessary or expedient to make the Plan or Award fully effective.

(iii)To settle all controversies regarding the Plan and Awards granted under it.

(iv)To accelerate the time at which an Award may first be exercised or the time during which an Award or any part thereof will vest, notwithstanding the provisions in the Award Agreement stating the time at which it may first be exercised or the time during which it will vest.

(v)To prohibit the exercise of any Option, SAR or other exercisable Award during a period of up to 30 days prior to the consummation of any pending stock dividend, stock split, combination or exchange of shares, merger, consolidation or other distribution (other than normal cash dividends) of Company assets to stockholders, or any other change affecting the shares of Common Stock or the share price of the Common Stock including any Corporate Transaction, for reasons of administrative convenience.

(vi)To suspend or terminate the Plan at any time. Suspension or termination of the Plan will not Materially Impair rights and obligations under any Award granted while the Plan is in effect except with the written consent of the affected Participant.

(vii)To amend the Plan in any respect the Board deems necessary or advisable; provided, however, that stockholder approval will be required for any amendment to the extent required by Applicable Law. Except as provided above, rights under any Award granted before amendment of the Plan will not be Materially Impaired by any amendment of the Plan unless (1) the Company requests the consent of the affected Participant, and (2) such Participant consents in writing.

(viii)To submit any amendment to the Plan for stockholder approval.

(ix)To approve forms of Award Agreements for use under the Plan and to amend the terms of any one or more Awards, including, but not limited to, amendments to provide terms more favorable to the Participant than previously provided in the Award Agreement, subject to any specified limits in the Plan that are not

subject to Board discretion; provided however, that, a Participant’s rights under any Award will not be Materially Impaired by any such amendment unless (1) the Company requests the consent of the affected Participant, and (2) such Participant consents in writing.

(x)Generally, to exercise such powers and to perform such acts as the Board deems necessary or expedient to promote the best interests of the Company and that are not in conflict with the provisions of the Plan or Awards.

(xi)To adopt such procedures and sub-plans as are necessary or appropriate to permit and facilitate participation in the Plan by, or take advantage of specific tax treatment for Awards granted to, Employees, Directors or Consultants who are foreign nationals or employed outside the United States (provided that Board approval will not be necessary for immaterial modifications to the Plan or any Award Agreement to ensure or facilitate compliance with the laws of the relevant foreign jurisdiction).

(c)Delegation to Committee.

(i)General. The Board may delegate some or all of the administration of the Plan to a Committee or Committees. If administration of the Plan is delegated to a Committee, the Committee will have, in connection with the administration of the Plan, the powers theretofore possessed by the Board that have been delegated to the Committee, including the power to delegate to another Committee or a subcommittee of the Committee any of the administrative powers the Committee is authorized to exercise (and references in this Plan to the Board will thereafter be to the Committee or subcommittee), subject, however, to such resolutions, not inconsistent with the provisions of the Plan, as may be adopted from time to time by the Board. Each Committee may retain the authority to concurrently administer the Plan with Committee or subcommittee to which it has delegated its authority hereunder and may, at any time, revest in such Committee some or all of the powers previously delegated. The Board may retain the authority to concurrently administer the Plan with any Committee and may, at any time, revest in the Board some or all of the powers previously delegated.

(ii)Rule 16b-3 Compliance. To the extent an Award is intended to qualify for the exemption from Section 16(b) of the Exchange Act that is available under Rule 16b-3 of the Exchange Act, the Award will be granted by the Board or a Committee that consists solely of two or more Non-Employee Directors, as determined under Rule 16b-3 (b)(3) of the Exchange Act and thereafter any action establishing or modifying the terms of the Award will be approved by the Board or a Committee meeting such requirements to the extent necessary for such exemption to remain available.

(d)Effect of Board’s Decision. All determinations, interpretations and constructions made by the Board or any Committee in good faith will not be subject to review by any person and will be final, binding and conclusive on all persons.

(e)Delegation to an Officer. The Board or any Committee may delegate to one or more Officers the authority to do one or both of the following (i) designate Employees who are not Officers to be recipients of Options and SARs (and, to the extent permitted by Applicable Law, other types of Awards) and, to the extent permitted by Applicable Law, the terms thereof, and (ii) determine the number of shares of Common Stock to be subject to such Awards granted to such Employees; provided, however, that the resolutions or charter adopted by the Board or any Committee evidencing such delegation will specify the total number of shares of Common Stock that may be subject to the Awards granted by such Officer and that such Officer may not grant an Award to himself or herself. Any such Awards will be granted on the applicable form of Award Agreement most recently approved for use by the Board or the Committee, unless otherwise provided in the resolutions approving the delegation authority. Notwithstanding anything to the contrary herein, neither the Board nor any Committee may delegate to an Officer who is acting solely in the capacity of an Officer (and not also as a Director) the authority to determine the Fair Market Value.

8.Tax Withholding

(a)Withholding Authorization. As a condition to acceptance of any Award under the Plan, a Participant authorizes withholding from payroll and any other amounts payable to such Participant, and otherwise agrees to make adequate provision for (including), any sums required to satisfy any U.S. federal, state, local and/or foreign tax or social insurance contribution withholding obligations of the Company or an Affiliate, if any, which arise in connection with the exercise, vesting or settlement of such Award, as applicable. Accordingly, a Participant may not be able to exercise an Award even though the Award is vested, and the Company shall have no obligation to issue shares of Common Stock subject to an Award, unless and until such obligations are satisfied.

(b)Satisfaction of Withholding Obligation. To the extent permitted by the terms of an Award Agreement, the Company may, in its sole discretion, satisfy any U.S. federal, state, local and/or foreign tax or social insurance withholding obligation relating to an Award by any of the following means or by a combination of such means: (i) causing the Participant to tender a cash payment; (ii) withholding shares of Common Stock from the shares of Common Stock issued or otherwise issuable to the Participant in connection with the Award; (iii) withholding cash from an Award settled in cash; (iv) withholding payment from any amounts otherwise payable to the Participant; (v) by allowing a Participant to effectuate a “cashless exercise” pursuant to a program developed under Regulation T as promulgated by the Federal Reserve Board; or (vi) by such other method as may be set forth in the Award Agreement.

(c)No Obligation to Notify or Minimize Taxes; No Liability to Claims. Except as required by Applicable Law the Company has no duty or obligation to any Participant to advise such holder as to the time or manner of exercising such Award. Furthermore, the Company has no duty or obligation to warn or otherwise advise such holder of a pending termination or expiration of an Award or a possible period in which the Award may not be exercised. The Company has no duty or obligation to minimize the tax consequences of an Award to the holder of such Award and will not be liable to any holder of an Award for any adverse tax consequences to such holder in connection with an Award. As a condition to accepting an Award under the Plan, each Participant (i) agrees to not make any claim against the Company, or any of its Officers, Directors, Employees or Affiliates related to tax liabilities arising from such Award or other Company compensation and (ii) acknowledges that such Participant was advised to consult with his or her own personal tax, financial and other legal advisors regarding the tax consequences of the Award and has either done so or knowingly and voluntarily declined to do so. Additionally, each Participant acknowledges any Option or SAR granted under the Plan is exempt from Section 409A only if the exercise or strike price is at least equal to the “fair market value” of the Common Stock on the date of grant as determined by the Internal Revenue Service and there is no other impermissible deferral of compensation associated with the Award. Additionally, as a condition to accepting an Option or SAR granted under the Plan, each Participant agrees not make any claim against the Company, or any of its Officers, Directors, Employees or Affiliates in the event that the Internal Revenue Service asserts that such exercise price or strike price is less than the “fair market value” of the Common Stock on the date of grant as subsequently determined by the Internal Revenue Service.

(d)Withholding Indemnification. As a condition to accepting an Award under the Plan, in the event that the amount of the Company’s and/or its Affiliate’s withholding obligation in connection with such Award was greater than the amount actually withheld by the Company and/or its Affiliates, each Participant agrees to indemnify and hold the Company and/or its Affiliates harmless from any failure by the Company and/or its Affiliates to withhold the proper amount.

9.Miscellaneous.

(a)Source of Shares. The stock issuable under the Plan will be shares of authorized but unissued or reacquired Common Stock, including shares repurchased by the Company on the open market or otherwise.

(b)Use of Proceeds from Sales of Common Stock. Proceeds from the sale of shares of Common Stock pursuant to Awards will constitute general funds of the Company.

(c)Corporate Action Constituting Grant of Awards. Corporate action constituting a grant by the Company of an Award to any Participant will be deemed completed as of the date of such corporate action, unless otherwise determined by the Board, regardless of when the instrument, certificate, or letter evidencing the Award is communicated to, or actually received or accepted by, the Participant. In the event that the corporate records (e.g., Board consents, resolutions or minutes) documenting the corporate action approving the grant contain terms (e.g., exercise price, vesting schedule or number of shares) that are inconsistent with those in the Award Agreement or related grant documents as a result of a clerical error in the Award Agreement or related grant documents, the corporate records will control and the Participant will have no legally binding right to the incorrect term in the Award Agreement or related grant documents.

(d)Stockholder Rights. No Participant will be deemed to be the holder of, or to have any of the rights of a holder with respect to, any shares of Common Stock subject to such Award unless and until (i) such Participant has satisfied all requirements for exercise of the Award pursuant to its terms, if applicable, and (ii) the issuance of the Common Stock subject to such Award is reflected in the records of the Company.

(e)No Employment or Other Service Rights. Nothing in the Plan, any Award Agreement or any other instrument executed thereunder or in connection with any Award granted pursuant thereto will confer upon any Participant any right to continue to serve the Company or an Affiliate in the capacity in effect at the time the Award was granted or affect the right of the Company or an Affiliate to terminate at will and without regard to any future vesting opportunity that a Participant may have with respect to any Award (i) the employment of an

Employee with or without notice and with or without cause, (ii) the service of a Consultant pursuant to the terms of such Consultant’s agreement with the Company or an Affiliate, or (iii) the service of a Director pursuant to the Bylaws of the Company or an Affiliate, and any applicable provisions of the corporate law of the state or foreign jurisdiction in which the Company or the Affiliate is incorporated, as the case may be. Further, nothing in the Plan, any Award Agreement or any other instrument executed thereunder or in connection with any Award will constitute any promise or commitment by the Company or an Affiliate regarding the fact or nature of future positions, future work assignments, future compensation or any other term or condition of employment or service or confer any right or benefit under the Award or the Plan unless such right or benefit has specifically accrued under the terms of the Award Agreement and/or Plan.

(f)Change in Time Commitment. In the event a Participant’s regular level of time commitment in the performance of his or her services for the Company and any Affiliates is reduced (for example, and without limitation, if the Participant is an Employee of the Company and the Employee has a change in status from a full-time Employee to a part-time Employee or takes an extended leave of absence) after the date of grant of any Award to the Participant, the Board may determine, to the extent permitted by Applicable Law, to (i) make a corresponding reduction in the number of shares or cash amount subject to any portion of such Award that is scheduled to vest or become payable after the date of such change in time commitment, and (ii) in lieu of or in combination with such a reduction, extend the vesting or payment schedule applicable to such Award. In the event of any such reduction, the Participant will have no right with respect to any portion of the Award that is so reduced or extended.

(g)Execution of Additional Documents. As a condition to accepting an Award under the Plan, the Participant agrees to execute any additional documents or instruments necessary or desirable, as determined in the Plan Administrator’s sole discretion, to carry out the purposes or intent of the Award, or facilitate compliance with securities and/or other regulatory requirements, in each case at the Plan Administrator’s request.

(h)Electronic Delivery and Participation. Any reference herein or in an Award Agreement to a “written” agreement or document will include any agreement or document delivered electronically, filed publicly at www.sec.gov (or any successor website thereto) or posted on the Company’s intranet (or other shared electronic medium controlled by the Company to which the Participant has access). By accepting any Award, the Participant consents to receive documents by electronic delivery and to participate in the Plan through any on-line electronic system established and maintained by the Plan Administrator or another third party selected by the Plan Administrator. The form of delivery of any Common Stock (e.g., a stock certificate or electronic entry evidencing such shares) shall be determined by the Company.

(i)Clawback/Recovery. All Awards granted under the Plan will be subject to recoupment in accordance with any clawback policy that the Company is required to adopt pursuant to the listing standards of any national securities exchange or association on which the Company’s securities are listed or as is otherwise required by the Dodd-Frank Wall Street Reform and Consumer Protection Act or other Applicable Law and any clawback policy that the Company otherwise adopts, to the extent applicable and permissible under Applicable Law. In addition, the Board may impose such other clawback, recovery or recoupment provisions in an Award Agreement as the Board determines necessary or appropriate, including but not limited to a reacquisition right in respect of previously acquired shares of Common Stock or other cash or property upon the occurrence of Cause. No recovery of compensation under such a clawback policy will be an event giving rise to a Participant’s right to voluntary terminate employment upon a “resignation for good reason,” or for a “constructive termination” or any similar term under any plan of or agreement with the Company.

(j)Securities Law Compliance. A Participant will not be issued any shares in respect of an Award unless either (i) the shares are registered under the Securities Act; or (ii) the Company has determined that such issuance would be exempt from the registration requirements of the Securities Act. Each Award also must comply with other Applicable Law governing the Award, and a Participant will not receive such shares if the Company determines that such receipt would not be in material compliance with Applicable Law.

(k)Transfer or Assignment of Awards; Issued Shares. Except as expressly provided in the Plan or the form of Award Agreement, Awards granted under the Plan may not be transferred or assigned by the Participant. After the vested shares subject to an Award have been issued, or in the case of Restricted Stock Awards and similar awards, after the issued shares have vested, the holder of such shares is free to assign, hypothecate, donate, encumber or otherwise dispose of any interest in such shares provided that any such actions are in compliance with the provisions herein, the terms of the Trading Policy and Applicable Law.

(l)Effect on Other Employee Benefit Plans. The value of any Award granted under the Plan, as determined upon grant, vesting or settlement, shall not be included as compensation, earnings, salaries, or other similar terms used when calculating any Participant’s benefits under any employee benefit plan sponsored by the

Company or any Affiliate, except as such plan otherwise expressly provides. The Company expressly reserves its rights to amend, modify, or terminate any of the Company’s or any Affiliate’s employee benefit plans.

(m)Deferrals. To the extent permitted by Applicable Law, the Board, in its sole discretion, may determine that the delivery of Common Stock or the payment of cash, upon the exercise, vesting or settlement of all or a portion of any Award may be deferred and may also establish programs and procedures for deferral elections to be made by Participants. Deferrals by will be made in accordance with the requirements of Section 409A.

(n)Section 409A. Unless otherwise expressly provided for in an Award Agreement, the Plan and Award Agreements will be interpreted to the greatest extent possible in a manner that makes the Plan and the Awards granted hereunder exempt from Section 409A, and, to the extent not so exempt, in compliance with the requirements of Section 409A. If the Board determines that any Award granted hereunder is not exempt from and is therefore subject to Section 409A, the Award Agreement evidencing such Award will incorporate the terms and conditions necessary to avoid the consequences specified in Section 409A(a)(l) of the Code, and to the extent an Award Agreement is silent on terms necessary for compliance, such terms are hereby incorporated by reference into the Award Agreement. Notwithstanding anything to the contrary in this Plan (and unless the Award Agreement specifically provides otherwise), if the shares of Common Stock are publicly traded, and if a Participant holding an Award that constitutes “deferred compensation” under Section 409A is a “specified employee” for purposes of Section 409A, no distribution or payment of any amount that is due because of a “separation from service” (as defined in Section 409A without regard to alternative definitions thereunder) will be issued or paid before the date that is six months and one day following the date of such Participant’s “separation from service” or, if earlier, the date of the Participant’s death, unless such distribution or payment can be made in a manner that complies with Section 409A, and any amounts so deferred will be paid in a lump sum on the day after such six month period elapses, with the balance paid thereafter on the original schedule.

(o)Choice of Law. This Plan and any controversy arising out of or relating to this Plan shall be governed by, and construed in accordance with, the internal laws of the State of Delaware, without regard to conflict of law principles that would result in any application of any law other than the law of the State of Delaware.

10.Covenants of the Company.

(a)Compliance with Law. The Company will seek to obtain from each regulatory commission or agency, as may be deemed to be necessary, having jurisdiction over the Plan such authority as may be required to grant Awards and to issue and sell shares of Common Stock upon exercise or vesting of the Awards; provided, however, that this undertaking will not require the Company to register under the Securities Act the Plan, any Award or any Common Stock issued or issuable pursuant to any such Award. If, after reasonable efforts and at a reasonable cost, the Company is unable to obtain from any such regulatory commission or agency the authority that counsel for the Company deems necessary or advisable for the lawful issuance and sale of Common Stock under the Plan, the Company will be relieved from any liability for failure to issue and sell Common Stock upon exercise or vesting of such Awards unless and until such authority is obtained. A Participant is not eligible for the grant of an Award or the subsequent issuance of Common Stock pursuant to the Award if such grant or issuance would be in violation of any Applicable Law.

11.Additional Rules for Awards Subject to Section 409A.

(a)Application. Unless the provisions of this Section of the Plan are expressly superseded by the provisions in the form of Award Agreement, the provisions of this Section shall apply and shall supersede anything to the contrary set forth in the Award Agreement for a Non-Exempt Award.

(b)Non-Exempt Awards Subject to Non-Exempt Severance Arrangements. To the extent a Non-Exempt Award is subject to Section 409A due to application of a Non-Exempt Severance Arrangement, the following provisions of this subsection (b) apply.

(i)If the Non-Exempt Award vests in the ordinary course during the Participant’s Continuous Service in accordance with the vesting schedule set forth in the Award Agreement, and does not accelerate vesting under the terms of a Non-Exempt Severance Arrangement, in no event will the shares be issued in respect of such Non-Exempt Award any later than the later of: (i) December 31st of the calendar year that includes the applicable vesting date, or (ii) the 60th day that follows the applicable vesting date.

(ii)If vesting of the Non-Exempt Award accelerates under the terms of a Non-Exempt Severance Arrangement in connection with the Participant’s Separation from Service, and such vesting acceleration provisions were in effect as of the date of grant of the Non-Exempt Award and, therefore, are part of the terms of

such Non-Exempt Award as of the date of grant, then the shares will be earlier issued in settlement of such Non-Exempt Award upon the Participant’s Separation from Service in accordance with the terms of the Non-Exempt Severance Arrangement, but in no event later than the 60th Jay that follows the date of the Participant’s Separation from Service. However, if at the time the shares would otherwise be issued the Participant is subject to the distribution limitations contained in Section 409A applicable to “specified employees,” as defined in Section 409A(a)(2)(B)(i) of the Code, such shares shall not be issued before the date that is six months following the date of such Participant’s Separation from Service, or, if earlier, the date of the Participant’s death that occurs within such six month period.

(iii)If vesting of a Non-Exempt Award accelerates under the terms of a Non-Exempt Severance Arrangement in connection with a Participant’s Separation from Service, and such vesting acceleration provisions were not in effect as of the date of grant of the Non-Exempt Award and, therefore, are not a part of the terms of such Non-Exempt Award on the date of grant, then such acceleration of vesting of the Non-Exempt Award shall not accelerate the issuance date of the shares, but the shares shall instead be issued on the same schedule as set forth in the Grant Notice as if they had vested in the ordinary course during the Participant’s Continuous Service, notwithstanding the vesting acceleration of the Non-Exempt Award. Such issuance schedule is intended to satisfy the requirements of payment on a specified date or pursuant to a fixed schedule, as provided under Treasury Regulations Section 1.409A-3(a)(4).

(c)Treatment of Non-Exempt Awards Upon a Corporate Transaction for Employees and Consultants. The provisions of this subsection (c) shall apply and shall supersede anything to the contrary set forth in the Plan with respect to the permitted treatment of any Non-Exempt Award in connection with a Corporate Transaction if the Participant was either an Employee or Consultant upon the applicable date of grant of the Non-Exempt Award.

(i)Vested Non-Exempt Awards. The following provisions shall apply to any Vested Non-Exempt Award in connection with a Corporate Transaction:

(1)If the Corporate Transaction is also a Section 409A Change in Control then the Acquiring Entity may not assume, continue or substitute the Vested Non-Exempt Award. Upon the Section 409A Change in Control the settlement of the Vested Non-Exempt Award will automatically be accelerated and the shares will be immediately issued in respect of the Vested Non-Exempt Award. Alternatively, the Company may instead provide that the Participant will receive a cash settlement equal to the Fair Market Value of the shares that would otherwise be issued to the Participant upon the Section 409A Change in Control.

(2)If the Corporate Transaction is not also a Section 409A Change in Control, then the Acquiring Entity must either assume, continue or substitute each Vested Non-Exempt Award. The shares to be issued in respect of the Vested Non-Exempt Award shall be issued to the Participant by the Acquiring Entity on the same schedule that the shares would have been issued to the Participant if the Corporate Transaction had not occurred. In the Acquiring Entity’s discretion, in lieu of an issuance of shares, the Acquiring Entity may instead substitute a cash payment on each applicable issuance date, equal to the Fair Market Value of the shares that would otherwise be issued to the Participant on such issuance dates, with the determination of the Fair Market Value of the shares made on the date of the Corporate Transaction.

(ii)Unvested Non-Exempt Awards. The following provisions shall apply to any Unvested Non-Exempt Award unless otherwise determined by the Board pursuant to subsection (e) of this Section.

(1)In the event of a Corporate Transaction, the Acquiring Entity shall assume, continue or substitute any Unvested Non-Exempt Award. Unless otherwise determined by the Board, any Unvested Non-Exempt Award will remain subject to the same vesting and forfeiture restrictions that were applicable to the Award prior to the Corporate Transaction. The shares to be issued in respect of any Unvested Non-Exempt Award shall be issued to the Participant by the Acquiring Entity on the same schedule that the shares would have been issued to the Participant if the Corporate Transaction had not occurred. In the Acquiring Entity’s discretion, in lieu of an issuance of shares, the Acquiring Entity may instead substitute a cash payment on each applicable issuance date, equal to the Fair Market Value of the shares that would otherwise be issued to the Participant on such issuance dates, with the determination of Fair Market Value of the shares made on the date of the Corporate Transaction.

(2)If the Acquiring Entity will not assume, substitute or continue any Unvested Non-Exempt Award in connection with a Corporate Transaction, then such Award shall automatically terminate and be forfeited upon the Corporate Transaction with no consideration payable to any Participant in respect of such forfeited Unvested Non-Exempt Award. Notwithstanding the foregoing, to the extent permitted and in compliance with the requirements of Section 409A, the Board may in its discretion determine to elect to accelerate the vesting and settlement of the Unvested Non-Exempt Award upon the Corporate Transaction, or instead substitute a cash

payment equal to the Fair Market Value of such shares that would otherwise be issued to the Participant, as further provided in subsection 11(e) below. In the absence of such discretionary election by the Board, any Unvested Non-Exempt Award shall be forfeited without payment of any consideration to the affected Participants if the Acquiring Entity will not assume, substitute or continue the Unvested Non-Exempt Awards in connection with the Corporate Transaction.

(3)The foregoing treatment shall apply with respect to all Unvested Non-Exempt Awards upon any Corporate Transaction, and regardless of whether or not such Corporate Transaction is also a Section 409A Change in Control.

(d)Treatment of Non-Exempt Awards Upon a Corporate Transaction for Non-Employee Directors. The following provisions of this subsection (d) shall apply and shall supersede anything to the contrary that may be set forth in the Plan with respect to the permitted treatment of a Non-Exempt Director Award in connection with a Corporate Transaction.

(i)If the Corporate Transaction is also a Section 409A Change in Control then the Acquiring Entity may not assume, continue or substitute the Non-Exempt Director Award. Upon the Section 409A Change in Control the vesting and settlement of any Non-Exempt Director Award will automatically be accelerated and the shares will be immediately issued to the Participant in respect of the Non-Exempt Director Award. Alternatively, the Company may provide that the Participant will instead receive a cash settlement equal to the Fair Market Value of the shares that would otherwise be issued to the Participant upon the Section 409A Change in Control pursuant to the preceding provision.

(ii)If the Corporate Transaction is not also a Section 409A Change in Control, then the Acquiring Entity must either assume, continue or substitute the Non-Exempt Director Award. Unless otherwise determined by the Board, the Non-Exempt Director Award will remain subject to the same vesting and forfeiture restrictions that were applicable to the Award prior to the Corporate Transaction. The shares to be issued in respect of the Non-Exempt Director Award shall be issued to the Participant by the Acquiring Entity on the same schedule that the shares would have been issued to the Participant if the Corporate Transaction had not occurred. In the Acquiring Entity’s discretion, in lieu of an issuance of shares, the Acquiring Entity may instead substitute a cash payment on each applicable issuance date, equal to the Fair Market Value of the shares that would otherwise be issued to the Participant on such issuance dates, with the determination of Fair Market Value made on the date of the Corporate Transaction.

(e)If the RSU Award is a Non-Exempt Award, then the provisions in this Section 11(e) shall apply and supersede anything to the contrary that may be set forth in the Plan or the Award Agreement with respect to the permitted treatment of such Non-Exempt Award:

(i)Any exercise by the Board of discretion to accelerate the vesting of a Non-Exempt Award shall not result in any acceleration of the scheduled issuance dates for the shares in respect of the Non-Exempt Award unless earlier issuance of the shares upon the applicable vesting dates would be in compliance with the requirements of Section 409A.

(ii)The Company explicitly reserves the right to earlier settle any Non-Exempt Award to the extent permitted and in compliance with the requirements of Section 409A, including pursuant to any of the exemptions available in Treasury Regulations Section 1.409A-3 (j)(4)(ix).

(iii)To the extent the terms of any Non-Exempt Award provide that it will be settled upon a Change in Control or Corporate Transaction, to the extent it is required for compliance with the requirements of Section 409A, the Change in Control or Corporate Transaction event triggering settlement must also constitute a Section 409A Change in Control. To the extent the terms of a Non-Exempt Award provides that it will be settled upon a termination of employment or termination of Continuous Service, to the extent it is required for compliance with the requirements of Section 409A, the termination event triggering settlement must also constitute a Separation from Service. However, if at the time the shares would otherwise be issued to a Participant in connection with a Separation from Service such Participant is subject to the distribution limitations contained in Section 409A applicable to “specified employees,” as defined in Section 409A(a)(2)(B)(i) of the Code, such shares shall not be issued before the date that is six months following the date of the Participant’s Separation from Service, or, if earlier, the date of the Participant’s death that occurs within such six month period.

(iv)The provisions in this subsection (e) for delivery of the shares in respect of the settlement of an RSU Award that is a Non-Exempt Award are intended to comply with the requirements of Section 409A so that the delivery of the shares to the Participant in respect of such Non-Exempt Award will not trigger the additional tax imposed under Section 409A, and any ambiguities herein will be so interpreted.

12.Severability.

If all or any part of the Plan or any Award Agreement is declared by any court or governmental authority to be unlawful or invalid, such unlawfulness or invalidity shall not invalidate any portion of the Plan or such Award Agreement not declared to be unlawful or invalid. Any Section of the Plan or any Award Agreement (or part of such a Section) so declared to be unlawful or invalid shall, if possible, be construed in a manner which will give effect to the terms of such Section or part of a Section to the fullest extent possible while remaining lawful and valid.

13.Termination of the Plan.

The Board may suspend or terminate the Plan at any time. No Incentive Stock Options may be granted after the tenth anniversary of the earlier of: (i) the Adoption Date, or (ii) the date the Plan is approved by the Company’s stockholders. No Awards may be granted under the Plan while the Plan is suspended or after it is terminated.

14.Definitions.

As used in the Plan, the following definitions apply to the capitalized terms indicated below:

(a)“Acquiring Entity” means the surviving or acquiring corporation (or its parent company) in connection with a Corporate Transaction.

(b)“Adoption Date” means the date the Plan is approved by the Board or Compensation Committee.

(c)“Affiliate” means, at the time of determination, any “parent’’ or “subsidiary” of the Company as such terms are defined in Rule 405 promulgated under the Securities Act. The Board may determine the time or times at which “parent” or “subsidiary” status is determined within the foregoing definition.

(d)“Applicable Law” means shall mean any applicable securities, federal, state, foreign, material local or municipal or other law, statute, constitution, principle of common law, resolution, ordinance, code, edict, decree, rule, listing rule, regulation, judicial decision, ruling or requirement issued, enacted, adopted, promulgated, implemented or otherwise put into effect by or under the authority of any Governmental Body (including wider the authority of any applicable self-regulating organization such as the Nasdaq Stock Market, New York Stock Exchange, or the Financial Industry Regulatory Authority).

(e)“Available Reserve” means the number of shares of Common Stock available for issuance under the Acumen Pharmaceuticals, Inc. Amended & Restated 2021 Equity Incentive Plan as of the Effective Date.

(f)“Award” means any right to receive Common Stock, cash or other property granted under the Plan (including an Incentive Stock Option, a Nonstatutory Stock Option, a Restricted Stock Award, an RSU Award, a SAR, a Performance Award or any Other Award).

(g)“Award Agreement” means a written agreement between the Company and a Participant evidencing the terms and conditions of an Award. The Award Agreement generally consists of the Grant Notice and the agreement containing the written summary of the general terms and conditions applicable to the Award and which is provided to a Participant along with the Grant Notice.

(h)“Board” means the Board of Directors of the Company (or its designee). Any decision or determination made by the Board shall be a decision or determination that is made in the sole discretion of the Board (or its designee), and such decision or determination shall be final and binding on all Participants.

(i)“Capitalization Adjustment” means any change that is made in, or other events that occur with respect to, the Common Stock subject to the Plan or subject to any Award after the Effective Date without the receipt of consideration by the Company through merger, consolidation, reorganization, recapitalization, reincorporation, stock dividend, dividend in property other than cash, large nonrecurring cash dividend, stock split, reverse stock split, liquidating dividend, combination of shares, exchange of shares, change in corporate structure or any similar equity restructuring transaction, as that term is used in Statement of Financial Accounting Standards Board Accounting Standards Codification Topic 718 (or any successor thereto). Notwithstanding the foregoing, the conversion of any convertible securities of the Company will not be treated as a Capitalization Adjustment.

(j)“Cause” has the meaning ascribed to such term in any written agreement between the Participant and the Company defining such term and, in the absence of such agreement, such term means, with respect to a Participant, the occurrence of any of the following events: (i) such Participant’s attempted commission of, or participation in, a fraud or act of dishonesty against the Company; (ii) such Participant’s intentional, material violation of any contract or agreement between the Participant and the Company or of any statutory duty owed to the Company; (iii) such Participant’s unauthorized use or disclosure of the Company’s confidential information or trade secrets; or (iv) such Participant’s gross misconduct. The determination that a termination of the Participant’s Continuous Service is either for Cause or without Cause will be made by the Board with respect to Participants who are executive officers of the Company and by the Company’s Chief Executive Officer with respect to Participants who are not executive officers of the Company. Any determination by the Company that the Continuous Service of a Participant was terminated with or without Cause for the purposes of outstanding Awards held by such Participant will have no effect upon any determination of the rights or obligations of the Company or such Participant for any other purpose.

(k)“Change in Control’ or “Change of Control” means the occurrence, in a single transaction or in a series of related transactions, of any one or more of the following events; provided, however, to the extent necessary to avoid adverse personal income tax consequences to the Participant in connection with an Award, also constitutes a Section 409A Change in Control:

(i)any Exchange Act Person becomes the Owner, directly or indirectly, of securities of the Company representing more than 50% of the combined voting power of the Company’s then outstanding securities other than by virtue of a merger, consolidation or similar transaction. Notwithstanding the foregoing, a Change in Control shall not be deemed to occur (A) on account of the acquisition of securities of the Company directly from the Company, (B) on account of the acquisition of securities of the Company by an investor, any affiliate thereof or any other Exchange Act Person that acquires the Company’s securities in a transaction or series of related transactions the primary purpose of which is to obtain financing for the Company through the issuance of equity securities, or (C) solely because the level of Ownership held by any Exchange Act Person (the “Subject Person”) exceeds the designated percentage threshold of the outstanding voting securities as a result of a repurchase or other acquisition of voting securities by the Company reducing the number of shares outstanding, provided that if a Change in Control would occur (but for the operation of this sentence) as a result of the acquisition of voting securities by the Company, and after such share acquisition, the Subject Person becomes the Owner of any additional voting securities that, assuming the repurchase or other acquisition had not occurred, increases the percentage of the then outstanding voting securities Owned by the Subject Person over the designated percentage threshold, then a Change in Control shall be deemed to occur;

(ii)there is consummated a merger, consolidation or similar transaction involving (directly or indirectly) the Company and, immediately after the consummation of such merger, consolidation or similar transaction, the stockholders of the Company immediately prior thereto do not Own, directly or indirectly, either (A) outstanding voting securities representing more than 50% of the combined outstanding voting power of the surviving Entity in such merger, consolidation or similar transaction or (B) more than 50% of the combined outstanding voting power of the parent of the surviving Entity in such merger, consolidation or similar transaction, in each case in substantially the same proportions as their Ownership of the outstanding voting securities of the Company immediately prior to such transaction;

(iii)there is consummated a sale, lease, exclusive license or other disposition of all or substantially all of the consolidated assets of the Company and its Subsidiaries, other than a sale, lease, license or other disposition of all or substantially all of the consolidated assets of the Company and its Subsidiaries to an Entity, more than 50% of the combined voting power of the voting securities of which are Owned by stockholders of the Company in substantially the same proportions as their Ownership of the outstanding voting securities of the Company immediately prior to such sale, lease, license or other disposition; or

(iv)individuals who, on the date the Plan is adopted by the Board, are members of the Board (the “Incumbent Board”) cease for any reason to constitute at least a majority of the members of the Board; provided, however, that if the appointment or election (or nomination for election) of any new Board member was approved or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member shall, for purposes of this Plan, be considered as a member of the Incumbent Board.

Notwithstanding the foregoing or any other provision of this Plan, (A) the term Change in Control shall not include a sale of assets, merger or other transaction effected exclusively for the purpose of changing the domicile of the Company, and (B) the definition of Change in Control (or any analogous term) in an individual written agreement between the Company or any Affiliate and the Participant shall supersede the foregoing definition with

respect to Awards subject to such agreement; provided, however, that if no definition of Change in Control or any analogous term is set forth in such an individual written agreement, the foregoing definition shall apply.

(l)“Code” means the Internal Revenue Code of 1986, as amended, including any applicable regulations and guidance thereunder.

(m)“Committee” means the Compensation Committee and any other committee of Directors to whom authority has been delegated by the Board or Compensation Committee in accordance with the Plan.

(n)“Common Stock” means the common stock of the Company.

(o)“Company” means Acumen Pharmaceuticals, Inc., a Delaware corporation.

(p)“Compensation Committee” means the Compensation Committee of the Board.

(q)“Consultant” means any person, including an advisor, who is (i) engaged by the Company or an Affiliate to render consulting or advisory services and is compensated for such services, or (ii) serving as a member of the board of directors of an Affiliate and is compensated for such services. However, service solely as a Director, or payment of a fee for such service, will not cause a Director to be considered a “Consultant” for purposes of the Plan. Notwithstanding the foregoing, a person is treated as a Consultant under this Plan only if a Form S-8 Registration Statement under the Securities Act is available to register either the offer or the sale of the Company’s securities to such person.

(r)“Continuous Service” means that the Participant’s service with the Company or an Affiliate, whether as an Employee, Director or Consultant, is not interrupted or terminated. A change in the capacity in which the Participant renders service to the Company or an Affiliate as an Employee, Director or Consultant or a change in the Entity for which the Participant renders such service, provided that there is no interruption or termination of the Participant’s service with the Company or an Affiliate, will not terminate a Participant’s Continuous Service; provided, however, that if the Entity for which a Participant is rendering services ceases to qualify as an Affiliate, as determined by the Board, such Participant’s Continuous Service will be considered to have terminated on the date such Entity ceases to qualify as an Affiliate. For example, a change in status from an Employee of the Company to a Consultant of an Affiliate or to a Director will not constitute an interruption of Continuous Service. To the extent permitted by law, the Board or the chief executive officer of the Company, in that party’s sole discretion, may determine whether Continuous Service will be considered interrupted in the case of (i) any leave of absence approved by the Board or chief executive officer, including sick leave, military leave or any other personal leave, or (ii) transfers between the Company, an Affiliate, or their successors. Notwithstanding the foregoing, a leave of absence will be treated as Continuous Service for purposes of vesting in an Award only to such extent as may be provided in the Company’s leave of absence policy, in the written terms of any leave of absence agreement or policy applicable to the Participant, or as otherwise required by law. In addition, to the extent required for exemption from or compliance with Section 409A, the determination of whether there has been a termination of Continuous Service will be made, and such term will be construed, in a manner that is consistent with the definition of Separation from Service.

(s)“Corporate Transaction” means the consummation, in a single transaction or in a series of related transactions, of any one or more of the following events:

(i)a sale or other disposition of all or substantially all, as determined by the Board, of the consolidated assets of the Company and its Subsidiaries;

(ii)a sale or other disposition of at least 50% of the outstanding securities of the Company;

(iii)a merger, consolidation or similar transaction following which the Company is not the surviving corporation; or

(iv)a merger, consolidation or similar transaction following which the Company is the surviving corporation but the shares of Common Stock outstanding immediately preceding the merger, consolidation or similar transaction are converted or exchanged by virtue of the merger, consolidation or similar transaction into other property, whether in the form of securities, cash or otherwise.

Notwithstanding the foregoing or any other provision of this Plan, (A) the term Corporate Transaction shall not include a sale of assets, merger or other transaction effected exclusively for the purpose of changing the domicile

of the Company, (B) the definition of Corporate Transaction (or any analogous term) in an individual written agreement between the Company or any Affiliate and the Participant shall supersede the foregoing definition with respect to Awards subject to such agreement; provided, however, that if no definition of Corporate Transaction or any analogous term is set forth in such an individual written agreement, the foregoing definition shall apply, and (C) with respect to any nonqualified deferred compensation that becomes payable on account of the Corporate Transaction, the transaction or event described in clause (i), (ii), (iii) or (iv) also constitute a Section 409A Change in Control if required in order for the payment non to violate Section 409A of the Code.

(t)“determine” or “determined” means as determined by the Board or the Committee (or its designee) in its sole discretion.

(u)“Director” means a member of the Board.

(v)“Disability” means, with respect to a Participant, such Participant is unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment which can be expected to result in death or which has lasted or can be expected to last for a continuous period of not less than 12 months, as provided in Section 22(e)(3) of the Code, and will be determined by the Board on the basis of such medical evidence as the Board deems warranted under the circumstances.

(w)“Effective Date” means June 3, 2026, the date of the Company’s 2026 annual meeting of stockholders.

(x)“Employee” means any person employed by the Company or an Affiliate. However, service solely as a Director, or payment of a fee for such services, will not cause a Director to be considered an “Employee” for purposes of the Plan.

(y)“Entity” means a corporation, partnership, limited liability company or other entity.

(z)“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

(aa)“Exchange Act Person” means any natural person, Entity or “group” (within the meaning of Section 13(d) or 14(d) of the Exchange Act), except that “Exchange Act Person” will not include (i) the Company or any Subsidiary of the Company, (ii) any employee benefit plan of the Company or any Subsidiary of the Company or any trustee or other fiduciary holding securities under an employee benefit plan of the Company or any Subsidiary of the Company, (iii) an underwriter temporarily holding securities pursuant to a registered public offering of such securities, (iv) an Entity Owned, directly or indirectly, by the stockholders of the Company in substantially the same proportions as their Ownership of stock of the Company; or (v) any natural person, Entity or “group” (within the meaning of Section 13(d) or 14(d) of the Exchange Act) that, as of the Effective Date, is the Owner, directly or indirectly, of securities of the Company representing more than 50% of the combined voting power of the Company’s then outstanding securities.

(ab)“Fair Market Value” means, as of any date, unless otherwise determined by the Board, the value of the Common Stock (as determined on a per share or aggregate basis, as applicable) determined as follows:

(i)If the Common Stock is listed on any established stock exchange or traded on any established market, the Fair Market Value will be the closing sales price for such stock as quoted on such exchange or market (or the exchange or market with the greatest volume of trading in the Common Stock) on the date of determination, as reported in a source the Board deems reliable.

(ii)If there is no closing sales price for the Common Stock on the date of determination, then the Fair Market Value will be the closing selling price on the last preceding date for which such quotation exists.

(iii)In the absence of such markets for the Common Stock, or if otherwise determined by the Board, the Fair Market Value will be determined by the Board in good faith and in a manner that complies with Sections 409A and 422 of the Code.

(ac)“Governmental Body” means any: (a) nation, state, commonwealth, province, territory, county, municipality, district or other jurisdiction of any nature; (b) federal, state, local, municipal, foreign or other government; (c) governmental or regulatory body, or quasi-governmental body of any nature (including any

governmental division, department, administrative agency or bureau, commission, authority, instrumentality, official, ministry, fund, foundation, center, organization, unit, body or Entity and any court or other tribunal, and for the avoidance of doubt, any tax authority) or other body exercising similar powers or authority; or (d) self-regulatory organization (including the Nasdaq Stock Market, New York Stock Exchange, and the Financial Industry Regulatory Authority).

(ad)“Grant Notice” means the notice provided to a Participant that he or she has been granted an Award under the Plan and which includes the name of the Participant, the type of Award, the date of grant of the Award, number of shares of Common Stock subject to the Award or potential cash payment right, (if any), the vesting schedule for the Award (if any) and other key terms applicable to the Award.

(ae)“Incentive Stock Option” means an option granted pursuant to Section 4 of the Plan that is intended to be, and qualifies as, an “incentive stock option” within the meaning of Section 422 of the Code.

(af)“Materially Impair” means any amendment to the terms of the Award that materially adversely affects the Participant’s rights under the Award. A Participant’s rights under an Award will not be deemed to have been Materially Impaired by any such amendment if the Board, in its sole discretion, determines that the amendment, taken as a whole, does not materially impair the Participant’s rights. For example, the following types of amendments to the terms of an Award do not Materially Impair the Participant’s rights under the Award: (i) imposition of reasonable restrictions on the minimum number of shares subject to an Option that may be exercised; (ii) to maintain the qualified status of the Award as an Incentive Stock Option under Section 422 of the Code; (iii) to change the terms of an Incentive Stock Option in a manner that disqualifies, impairs or otherwise affects the qualified status of the Award as an Incentive Stock Option under Section 422 of the Code; (iv) to clarify the manner of exemption from, or to bring the Award into compliance with or qualify it for an exemption from, Section 409A; or (v) to comply with other Applicable Laws.

(ag)“Non-Employee Director” means a Director who either (i) is not a current employee or officer of the Company or an Affiliate, does not receive compensation, either directly or indirectly, from the Company or an Affiliate for services rendered as a consultant or in any capacity other than as a Director (except for an amount as to which disclosure would not be required under Item 404(a) of Regulation S-K promulgated pursuant to the Securities Act (“Regulation S-K”)), does not possess an interest in any other transaction for which disclosure would be required under Item 404(a) of Regulation S-K, and is not engaged in a business relationship for which disclosure would be required pursuant to Item 404(b) of Regulation S-K; or (ii) is otherwise considered a “non-employee director” for purposes of Rule 16b-3.

(ah)“Non-Exempt Award” means any Award that is subject to, and not exempt from, Section 409A, including as the result of (i) a deferral of the issuance of the shares subject to the Award which is elected by the Participant or imposed by the Company, (ii) the terms of any Non-Exempt Severance Arrangement.

(ai)“Non-Exempt Director Award” means a Non-Exempt Award granted to a Participant who was a Director but not an Employee on the applicable grant date.

(aj)“Non-Exempt Severance Arrangement” means a severance arrangement or other agreement between the Participant and the Company that provides for acceleration of vesting of an Award and issuance of the shares in respect of such Award upon the Participant’s termination of employment or separation from service (as such term is defined in Section 409A(a)(2)(A)(i) of the Code (and without regard to any alternative definition thereunder))(“Separation from Service”) and such severance benefit does not satisfy the requirements for an exemption from application of Section 409A provided under Treasury Regulations Section 1.409A-1(b)(4), 1.409A-1(b)(9) or otherwise.

(ak)“Nonstatutory Stock Option” means any option granted pursuant to Section 4 of the Plan that does not qualify as an Incentive Stock Option.

(al)“Officer” means a person who is an officer of the Company within the meaning of Section 16 of the Exchange Act.

(am)“Option” means an Incentive Stock Option or a Nonstatutory Stock Option to purchase shares of Common Stock granted pursuant to the Plan.

(an)“Option Agreement” means a written agreement between the Company and the Optionholder evidencing the terms and conditions of the Option grant. The Option Agreement includes the Grant Notice for the Option and the agreement containing the written summary of the general terms and conditions applicable to the

Option and which is provided to a Participant along with the Grant Notice. Each Option Agreement will be subject to the terms and conditions of the Plan.

(ao)“Optionholder” means a person to whom an Option is granted pursuant to the Plan or, if applicable, such other person who holds an outstanding Option.

(ap)“Other Award” means an award based in whole or in part by reference to the Common Stock which is granted pursuant to the terms and conditions of Section 5(c).

(aq)“Other Award Agreement” means a written agreement between the Company and a holder of an Other Award evidencing the terms and conditions of an Other Award grant. Each Other Award Agreement will be subject to the terms and conditions of the Plan.

(ar)“Own,” “Owned,” “Owner,” “Ownership” means that a person or Entity will be deemed to “Own,” to have “Owned,” to be the “Owner” of, or to have acquired “Ownership” of securities if such person or Entity, directly or indirectly, through any contract, arrangement, understanding, relationship or otherwise, has or shares voting power, which includes the power to vote or to direct the voting, with respect to such securities.

(as)“Participant” means an Employee, Director or Consultant to whom an Award is granted pursuant to the Plan or, if applicable, such other person who holds an outstanding Award.

(at)“Performance Award” means an Award that may vest or may be exercised or a cash award that may vest or become earned and paid contingent upon the attainment during a Performance Period of certain Performance Goals and which is granted under the terms and conditions of Section 5(b) pursuant to such terms as are approved by the Board. In addition, to the extent permitted by Applicable Law and set forth in the applicable Award Agreement, the Board may determine that cash or other property may be used in payment of Performance Awards. Performance Awards that are settled in cash or other property are not required to be valued in whole or in part by reference to, or otherwise based on, the Common Stock.

(au)“Performance Criteria” means the one or more criteria that the Board will select for purposes of establishing the Performance Goals for a Performance Period. The Performance Criteria that will be used to establish such Performance Goals may be based on any one of, or combination of, the following as determined by the Board: earnings (including earnings per share and net earnings); earnings before interest, taxes and depreciation; earnings before interest, taxes, depreciation and amortization; total stockholder return; return on equity or average stockholder’s equity; return on assets, investment, or capital employed; stock price; margin (including gross margin); income (before or after taxes); operating income; operating income after taxes; pre-tax profit; operating cash flow; sales or revenue targets; increases in revenue or product revenue; expenses and cost reduction goals; improvement in or attainment of working capital levels; economic value added (or an equivalent metric); market share; cash flow; cash flow per share; share price performance; debt reduction; customer satisfaction; stockholders’ equity; capital expenditures; debt levels; operating profit or net operating profit; workforce diversity; growth of net income or operating income; billings; financing; regulatory milestones; stockholder liquidity; corporate governance and compliance; intellectual property; personnel matters; progress of internal research; progress of partnered programs; partner satisfaction; budget management; partner or collaborator achievements; internal controls, including those related to the Sarbanes-Oxley Act of 2002; investor relations, analysts and communication; implementation or completion of projects or processes; employee retention; number of users, including unique users; strategic partnerships or transactions (including in-licensing and out-licensing of intellectual property); establishing relationships with respect to the marketing, distribution and sale of the Company’s products; supply chain achievements; co-development, co-marketing, profit sharing, joint venture or other similar arrangements; individual performance goals; corporate development and planning goals; and other measures of performance selected by the Board or Committee whether or not listed herein.

(av)“Performance Goals” means, for a Performance Period, the one or more goals established by the Board for the Performance Period based upon the Performance Criteria. Performance Goals may be based on a Company-wide basis, with respect to one or more business units, divisions, Affiliates, or business segments, and in either absolute terms or relative to the performance of one or more comparable companies or the performance of one or more relevant indices. Unless specified otherwise by the Board (i) in the Award Agreement at the time the Award is granted or (ii) in such other document setting forth the Performance Goals at the time the Performance Goals are established, the Board will appropriately make adjustments in the method of calculating the attainment of Performance Goals for a Performance Period as follows: (1) to exclude restructuring and/or other nonrecurring charges; (2) to exclude exchange rate effects; (3) to exclude the effects of changes to generally accepted accounting principles; (4) to exclude the effects of any statutory adjustments to corporate tax rates; (5) to exclude the effects of items that are “unusual” in nature or occur “infrequently” as determined under generally accepted accounting principles; (6) to exclude the dilutive effects of acquisitions or joint ventures; (7) to assume that any business

divested by the Company achieved performance objectives at targeted levels during the balance of a Performance Period following such divestiture; (8) to exclude the effect of any change in the outstanding shares of Common Stock by reason of any stock dividend or split, stock repurchase, reorganization, recapitalization, merger, consolidation, spin-off, combination or exchange of shares or other similar corporate change, or any distributions to common stockholders other than regular cash dividends; (9) to exclude the effects of stock based compensation and the award of bonuses under the Company’s bonus plans; (10) to exclude costs incurred in connection with potential acquisitions or divestitures that are required to expense under generally accepted accounting principles; and (11) to exclude the goodwill and intangible asset impairment charges that are required to be recorded under generally accepted accounting principles. In addition, the Board retains the discretion to reduce or eliminate the compensation or economic benefit due upon attainment of Performance Goals and to define the manner of calculating the Performance Criteria it selects to use for such Performance Period. Partial achievement of the specified criteria may result in the payment or vesting corresponding to the degree of achievement as specified in the Award Agreement or the written terms of a Performance Award.

(aw)“Performance Period” means the period of time selected by the Board over which the attainment of one or more Performance Goals will be measured for the purpose of determining a Participant’s right to vesting or exercise of an Award. Performance Periods may be of varying and overlapping duration, at the sole discretion of the Board.

(ax)“Plan” means this Acumen Pharmaceuticals, Inc. Amended and Restated 2021 Equity Incentive Plan, as it may be amended or amended and restated from time to time.

(ay)“Plan Administrator” means the person, persons, and/or third-party administrator designated by the Company to administer the day to day operations of the Plan and the Company’s other equity incentive programs.

(az)“Post-Termination Exercise Period” means the period following termination of a Participant’s Continuous Service within which an Option or SAR is exercisable, as specified in Section 4(h).

(ba)“Prior Plan” means the Acumen Pharmaceuticals, Inc. Amended and Restated Stock Performance Plan.

(bb)“Prospectus” means the document containing the Plan information specified in Section 10(a) of the Securities Act.

(bc)“Restricted Stock Award” or “RSA” means an Award of shares of Common Stock which is granted pursuant to the terms and conditions of Section 5(a).

(bd)“Restricted Stock Award Agreement” means a written agreement between the Company and a holder of a Restricted Stock Award evidencing the terms and conditions of a Restricted Stock Award grant. The Restricted Stock Award Agreement includes the Grant Notice for the Restricted Stock Award and the agreement containing the written summary of the general terms and conditions applicable to the Restricted Stock Award and which is provided to a Participant along with the Grant Notice. Each Restricted Stock Award Agreement will be subject to the terms and conditions of the Plan.

(be)“Returning Shares” means shares subject to outstanding stock awards granted under the Plan, prior to the Effective Date, and the Prior Plan and that, in each case, following the Effective Date: (A) are not issued because such stock award or any portion thereof expires or otherwise terminates without all of the shares covered by such stock award having been issued; (B) are not issued because such stock award or any portion thereof is settled in cash; (C) are forfeited back to or repurchased by the Company because of the failure to meet a contingency or condition required for the vesting of such shares; (D) are withheld or reacquired to satisfy the exercise, strike or purchase price; or (E) are withheld or reacquired to satisfy a tax withholding obligation.

(bf)“RSU Award” or “RSU” means an Award of restricted stock units representing the right to receive an issuance of shares of Common Stock which is granted pursuant to the terms and conditions of Section 5(a).

(bg)“RSU Award Agreement” means a written agreement between the Company and a holder of an RSU Award evidencing the terms and conditions of an RSU Award grant. The RSU Award Agreement includes the Grant Notice for the RSU Award and the agreement containing the written summary of the general terms and conditions applicable to the RSU Award and which is provided to a Participant along with the Grant Notice. Each RSU Award Agreement will be subject to the terms and conditions of the Plan.

(bh)“Rule 16b-3” means Rule 16b-3 promulgated under the Exchange Act or any successor to Rule 16b-3, as in effect from time to time.

(bi)“Rule 405” means Rule 405 promulgated under the Securities Act.

(bj)“Section 409A” means Section 409A of the Code and the regulations and other guidance thereunder.

(bk)“Section 409A Change in Control” means a change in the ownership or effective control of the Company, or in the ownership of a substantial portion of the Company’s assets, as provided in Section 409A(a)(2)(A)(v) of the Code and Treasury Regulations Section 1.409A-3(i)(5) (without regard to any alternative definition thereunder).

(bl)“Securities Act” means the Securities Act of 1933, as amended.

(bm)“Share Reserve” means the number of shares available for issuance under the Plan as set forth in Section 2(a).

(bn)“Stock Appreciation Right” or “SAR” means a right to receive the appreciation on Common Stock that is granted pursuant to the terms and conditions of Section 4.

(bo)“SAR Agreement” means a written agreement between the Company and a holder of a SAR evidencing the terms and conditions of a SAR grant. The SAR Agreement includes the Grant Notice for the SAR and the agreement containing the written summary of the general terms and conditions applicable to the SAR and which is provided to a Participant along with the Grant Notice. Each SAR Agreement will be subject to the terms and conditions of the Plan.

(bp)“Subsidiary” means, with respect to the Company, (i) any corporation of which more than 50% of the outstanding capital stock having ordinary voting power to elect a majority of the board of directors of such corporation (irrespective of whether, at the time, stock of any other class or classes of such corporation will have or might have voting power by reason of the happening of any contingency) is at the time, directly or indirectly, Owned by the Company, and (ii) any partnership, limited liability company or other entity in which the Company has a direct or indirect interest (whether in the form of voting or participation in profits or capital contribution) of more than 50%.

(bq)“Ten Percent Stockholder” means a person who Owns (or is deemed to Own pursuant to Section 424(d) of the Code) stock possessing more than 10% of the total combined voting power of all classes of stock of the Company or any Affiliate.

(br)“Trading Policy” means the Company’s policy permitting certain individuals to sell Company shares only during certain “window” periods and/or otherwise restricts the ability of certain individuals to transfer or encumber Company shares, as in effect from time to time.

(bs)“Unvested Non-Exempt Award” means the portion of any Non-Exempt Award that had not vested in accordance with its terms upon or prior to the date of any Corporate Transaction.

(bt)“Vested Non-Exempt Award” means the portion of any Non-Exempt Award that had vested in accordance with its terms upon or prior to the date of a Corporate Transaction.

Employee Stock Option Grant Package

ACUMEN PHARMACEUTICALS, INC.

STOCK OPTION GRANT NOTICE

(AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN)

Acumen Pharmaceuticals, Inc. (the “Company”), pursuant to its Amended & Restated 2021 Equity Incentive Plan (the “Plan”), has granted to you (“Optionholder”) an option to purchase the number of shares of the Common Stock set forth below (the “Option”). Your Option is subject to all of the terms and conditions as set forth herein and in the Plan, and the Stock Option Agreement and the Notice of Exercise, all of which are attached hereto and incorporated herein in their entirety. Capitalized terms not explicitly defined herein but defined in the Plan or the Stock Option Agreement shall have the meanings set forth in the Plan or the Stock Option Agreement, as applicable.



Optionholder:
Date of Grant:
Vesting Commencement Date:
Number of Shares of Common Stock Subject to Option:
Exercise Price (Per Share):
Total Exercise Price:
Expiration Date:


Type of Grant:			[Incentive Stock Option] OR [Nonstatutory Stock Option]

Exercise and Vesting Schedule:			Subject to the Optionholder’s Continuous Service through each applicable vesting date, the Option will vest as follows: [●]

Optionholder Acknowledgements: By your signature below or by electronic acceptance or authentication in a form authorized by the Company, you understand and agree that:

•The Option is governed by this Stock Option Grant Notice, and the provisions of the Plan and the Stock Option Agreement and the Notice of Exercise, all of which are made a part of this document. Unless otherwise provided in the Plan, this Grant Notice and the Stock Option Agreement (together, the “Option Agreement”) may not be modified, amended or revised except in a writing signed by you and a duly authorized officer of the Company.

•[If the Option is an Incentive Stock Option, it (plus other outstanding Incentive Stock Options granted to you) cannot be first exercisable for more than $100,000 in value (measured by exercise price) in any calendar year. Any excess over $100,000 is a Nonstatutory Stock Option.]

•You consent to receive this Grant Notice, the Stock Option Agreement, the Plan, the Prospectus and any other Plan-related documents by electronic delivery and to participate in the Plan through an on-line or electronic system established and maintained by the Company or another third party designated by the Company.

•You have read and are familiar with the provisions of the Plan, the Stock Option Agreement, the Notice of Exercise and the Prospectus. In the event of any conflict between the provisions in this Grant Notice, the Option Agreement, the Notice of Exercise, or the Prospectus and the terms of the Plan, the terms of the Plan shall control.

•The Option Agreement sets forth the entire understanding between you and the Company regarding the acquisition of Common Stock and supersedes all prior oral and written agreements, promises and/or representations on that subject with the exception of other equity awards previously granted to you and any written employment agreement, offer letter, severance agreement, written severance plan or policy, or other

Employee Stock Option Grant Package

written agreement between the Company and you in each case that specifies the terms that should govern this Option.

•Counterparts may be delivered via facsimile, electronic mail (including pdf or any electronic signature complying with the U.S. federal ESIGN Act of 2000, Uniform Electronic Transactions Act or other applicable law) or other transmission method and any counterpart so delivered will be deemed to have been duly and validly delivered and be valid and effective for all purposes.

ACUMEN PHARMACEUTICALS, INC.

OPTIONHOLDER:

By:

Signature

Title:

Date:

ATTACHMENTS: Stock Option Agreement, Amended & Restated 2021 Equity Incentive Plan, Notice of Exercise

Employee Stock Option Grant Package

ATTACHMENT I

STOCK OPTION AGREEMENT

Employee Stock Option Grant Package

ACUMEN PHARMACEUTICALS, INC.

AMENDED & RESTATED 2021 STOCK EQUITY PLAN

STOCK OPTION AGREEMENT

As reflected by your Stock Option Grant Notice (“Grant Notice”), Acumen Pharmaceuticals, Inc. (the “Company”) has granted you an option under its Amended & Restated 2021 Equity Incentive Plan (the “Plan”) to purchase a number of shares of Common Stock at the exercise price indicated in your Grant Notice (the “Option”). Capitalized terms not explicitly defined in this Agreement but defined in the Grant Notice or the Plan shall have the meanings set forth in the Grant Notice or Plan, as applicable. The terms of your Option as specified in the Grant Notice and this Stock Option Agreement constitute your Option Agreement.

The general terms and conditions applicable to your Option are as follows:

1. GOVERNING PLAN DOCUMENT. Your Option is subject to all the provisions of the Plan, including but not limited to the provisions in:

(a) Section 6 regarding the impact of a Capitalization Adjustment, dissolution, liquidation, or Corporate Transaction on your Option;

(b) Section 9(e) regarding the Company’s retained rights to terminate your Continuous Service notwithstanding the grant of the Option; and

Your Option is further subject to all interpretations, amendments, rules and regulations, which may from time to time be promulgated and adopted pursuant to the Plan. In the event of any conflict between the Option Agreement and the provisions of the Plan, the provisions of the Plan shall control.

2. EXERCISE.

(a) You may generally exercise the vested portion of your Option for whole shares of Common Stock at any time during its term by delivery of payment of the exercise price and applicable withholding taxes and other required documentation to the Plan Administrator in accordance with the exercise procedures established by the Plan Administrator, which may include an electronic submission. Please review Sections 4(i), 4(j) and
7(a)(v) of the Plan, which may restrict or prohibit your ability to exercise your Option during certain periods.

(b) To the extent permitted by Applicable Law, you may pay your Option exercise price as follows:

(i) cash, check, bank draft or money order;

(ii) subject to Company and/or Committee consent at the time of exercise, pursuant to a “cashless exercise” program as further described in Section 4(c)(ii) of the Plan if at the time of exercise the Common Stock is publicly traded;

(iii) subject to Company and/or Committee consent at the time of exercise, by delivery of previously owned shares of Common Stock as further described in Section 4(c)(iii) of the Plan; or

(iv) subject to Company and/or Committee consent at the time of exercise, if the Option is a Nonstatutory Stock Option, by a “net exercise” arrangement as further described in Section 4(c)(iv) of the Plan.

3. TERM. You may not exercise your Option before the commencement of its term or after its term expires. The term of your Option commences on the Date of Grant and expires upon the earliest of the following:

Employee Stock Option Grant Package

(a) immediately upon the termination of your Continuous Service for Cause;

(b) three months after the termination of your Continuous Service for any reason other than Cause, Disability or death;

(d) 18 months after your death if you die during your Continuous Service;

(e) immediately upon a Corporate Transaction if the Board has determined that the Option will terminate in connection with a Corporate Transaction,

(f) the Expiration Date indicated in your Grant Notice; or

(g) the day before the 10th anniversary of the Date of Grant.

Notwithstanding the foregoing, if you die during the period provided in Section 3(b) or 3(c) above, the term of your Option shall not expire until the earlier of (i) 18 months after your death, (ii) upon any termination of the Option in connection with a Corporate Transaction, (iii) the Expiration Date indicated in your Grant Notice, or (iv) the day before the tenth anniversary of the Date of Grant. Additionally, the Post-Termination Exercise Period of your Option may be extended as provided in Section 4(i) of the Plan.

To obtain the federal income tax advantages associated with an Incentive Stock Option, the Code requires that at all times beginning on the date of grant of your Option and ending on the day three months before the date of your Option’s exercise, you must be an employee of the Company or an Affiliate, except in the event of your death or Disability. If the Company provides for the extended exercisability of your Option under certain circumstances for your benefit, your Option will not necessarily be treated as an Incentive Stock Option if you exercise your Option more than three months after the date your employment terminates.

4. WITHHOLDING OBLIGATIONS. As further provided in Section 8 of the Plan: (a) you may not exercise your Option unless the applicable tax withholding obligations are satisfied, and (b) at the time you exercise your Option, in whole or in part, or at any time thereafter as requested by the Company, you hereby authorize withholding from payroll and any other amounts payable to you, and otherwise agree to make adequate provision for (including by means of a “cashless exercise” pursuant to a program developed under Regulation T as promulgated by the Federal Reserve Board to the extent permitted by the Company), any sums required to satisfy the federal, state, local and foreign tax withholding obligations, if any, which arise in connection with the exercise of your Option in accordance with the withholding procedures established by the Company. Accordingly, you may not be able to exercise your Option even though the Option is vested, and the Company shall have no obligation to issue shares of Common Stock subject to your Option, unless and until such obligations are satisfied. In the event that the amount of the Company’s withholding obligation in connection with your Option was greater than the amount actually withheld by the Company, you agree to indemnify and hold the Company harmless from any failure by the Company to withhold the proper amount.

5. INCENTIVE STOCK OPTION DISPOSITION REQUIREMENT. If your Option is an Incentive Stock Option, you must notify the Company in writing within 15 days after the date of any disposition of any of the shares of the Common Stock issued upon exercise of your Option that occurs within two years after the date of your Option grant or within one year after such shares of Common Stock are transferred upon exercise of your Option.

6. TRANSFERABILITY. Except as otherwise provided in Section 4(e) of the Plan, your Option is not transferable, except by will or by the applicable laws of descent and distribution, and is exercisable during your life only by you.

Employee Stock Option Grant Package

representative that is authorized to act on your behalf with respect to any escrow, indemnities and any contingent consideration.

8. NO LIABILITY FOR TAXES. As a condition to accepting the Option, you hereby (a) agree to not make any claim against the Company, or any of its Officers, Directors, Employees or Affiliates related to tax liabilities arising from the Option or other Company compensation and (b) acknowledge that you were advised to consult with your own personal tax, financial and other legal advisors regarding the tax consequences of the Option and have either done so or knowingly and voluntarily declined to do so. Additionally, you acknowledge that the Option is exempt from Section 409A only if the exercise price is at least equal to the “fair market value” of the Common Stock on the date of grant as determined by the Internal Revenue Service and there is no other impermissible deferral of compensation associated with the Option. Additionally, as a condition to accepting the Option, you agree not make any claim against the Company, or any of its Officers, Directors, Employees or Affiliates in the event that the Internal Revenue Service asserts that such exercise is less than the “fair market value” of the Common Stock on the date of grant as subsequently determined by the Internal Revenue Service.

9. SEVERABILITY. If any part of this Option Agreement or the Plan is declared by any court or governmental authority to be unlawful or invalid, such unlawfulness or invalidity will not invalidate any portion of this Option Agreement or the Plan not declared to be unlawful or invalid. Any Section of this Option Agreement (or part of such a Section) so declared to be unlawful or invalid will, if possible, be construed in a manner which will give effect to the terms of such Section or part of a Section to the fullest extent possible while remaining lawful and valid.

10. OTHER DOCUMENTS. You hereby acknowledge receipt of or the right to receive a document providing the information required by Rule 428(b)(1) promulgated under the Securities Act, which includes the Prospectus. In addition, you acknowledge receipt of the Company’s Trading Policy.

11. QUESTIONS. If you have questions regarding these or any other terms and conditions applicable to your Option, including a summary of the applicable federal income tax consequences please see the Prospectus.

* * * *

Employee Stock Option Grant Package

ATTACHMENT II

AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN

Employee Stock Option Grant Package

ATTACHMENT III

NOTICE OF EXERCISE

Employee Stock Option Grant Package

ACUMEN PHARMACEUTICALS, INC.

(AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN)

ACUMEN PHARMACEUTICALS, INC.

1210-1220 Washington Street, Suite 210

Newton, Massachusetts 02465

Date of Exercise:

This constitutes notice to Acumen Pharmaceuticals, Inc. (the “Company”) that I elect to purchase the below number of shares of Common Stock of the Company (the “Shares”) by exercising my Option for the price set forth below. Capitalized terms not explicitly defined in this Notice of Exercise but defined in the Grant Notice, Option Agreement or Amended & Restated 2021 Equity Incentive Plan (the “Plan”) shall have the meanings set forth in the Grant Notice, Option Agreement or Plan, as applicable. Use of certain payment methods is subject to Company and/or Committee consent and certain additional requirements set forth in the Option Agreement and the Plan.

Type of option (check one):

Incentive

☐

Nonstatutory

☐

Date of Grant:

Number of Shares as to which Option is exercised:

Certificates to be issued in name of:

Total exercise price:

Cash, check, bank draft or money order delivered herewith:

Value of Shares delivered herewith:

Regulation T Program (cashless exercise)

Value of Shares pursuant to net exercise:

By this exercise, I agree (i) to provide such additional documents as you may require pursuant to the terms of the Plan, (ii) to satisfy the tax obligations, if any, relating to the exercise of this Option as set forth in the Option Agreement, and (iii) if this exercise relates to an incentive stock option, to notify you in writing within 15 days after the date of any disposition of any of the Shares issued upon exercise of this Option that occurs within two years after the Date of Grant or within one year after such Shares are issued upon exercise of this Option.

Employee Stock Option Grant Package

Very truly yours,

Non-Employee Director Stock Option Grant Package

ACUMEN PHARMACEUTICALS, INC.

STOCK OPTION GRANT NOTICE

(AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN)



Optionholder:
Date of Grant:
Number of Shares of Common Stock Subject to Option:
Exercise Price (Per Share):
Total Exercise Price:
Expiration Date:



Type of Grant:						Nonstatutory Stock Option

Exercise and Vesting Schedule:						Subject to the Optionholder’s Continuous Service through each applicable vesting date, the Option will vest as follows, subject to the potential vesting acceleration described in Section 2 of the Stock Option Agreement: [Initial Grant][The shares subject to the Option shall vest and become exercisable in a series of [●] successive equal monthly installments measured from the Date of Grant.] [Annual Grant][The shares subject to the Option shall vest and become exercisable at the earlier of (i) the one-year anniversary of the Date of Grant and (ii) the date of the next annual meeting of the stockholders of the Company.]

Optionholder Acknowledgements: By your signature below or by electronic acceptance or authentication in a form authorized by the Company, you understand and agree that:

Non-Employee Director Stock Option Grant Package

written employment agreement, offer letter, severance agreement, written severance plan or policy, or other written agreement between the Company and you in each case that specifies the terms that should govern this Option.

ACUMEN PHARMACEUTICALS, INC. OPTIONHOLDER:

By:

Signature

Title:

Date:

ATTACHMENTS: Stock Option Agreement, Amended & Restated 2021 Equity Incentive Plan, Notice of Exercise

Non-Employee Director Stock Option Grant Package

ATTACHMENT I

STOCK OPTION AGREEMENT

Non-Employee Director Stock Option Grant Package

ACUMEN PHARMACEUTICALS, INC.

AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN

STOCK OPTION AGREEMENT

The general terms and conditions applicable to your Option are as follows:

1. GOVERNING PLAN DOCUMENT. Your Option is subject to all the provisions of the Plan, including but not limited to the provisions in:

(a) Section 6 regarding the impact of a Capitalization Adjustment, dissolution, liquidation, or Corporate Transaction on your Option;

(b) Section 9(e) regarding the Company’s retained rights to terminate your Continuous Service notwithstanding the grant of the Option; and

2. VESTING.

(a) Your Option will vest as provided in your Grant Notice, subject to the provisions contained herein and the terms of the Plan. Vesting will cease upon the termination of your Continuous Service. Notwithstanding the foregoing, if a Change in Control occurs and your Continuous Service has not terminated as of immediately prior to such Change in Control, then the vesting and exercisability of your Option will be accelerated in full upon such Change in Control.

(b) If any payment or benefit you would receive from the Company or otherwise in connection with a Change in Control or other similar transaction (a “280G Payment”) would (i) constitute a “parachute payment” within the meaning of Section 280G of the Code, and (ii) but for this sentence, be subject to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then any such 280G Payment (a “Payment”) shall be equal to the Reduced Amount. The “Reduced Amount” shall be either (x) the largest portion of the Payment that would result in no portion of the Payment (after reduction) being subject to the Excise Tax or (y) the largest portion, up to and including the total, of the Payment, whichever amount (i.e., the amount determined by clause (x) or by clause (y)), after taking into account all applicable federal, state and local employment taxes, income taxes, and the Excise Tax (all computed at the highest applicable marginal rate), results in your receipt, on an after-tax basis, of the greater economic benefit notwithstanding that all or some portion of the Payment may be subject to the Excise Tax. If a reduction in a Payment is required pursuant to the preceding sentence and the Reduced Amount is determined pursuant to clause (x) of the preceding sentence, the reduction shall occur in the manner (the “Reduction Method”) that results in the greatest economic benefit for you. If more than one method of reduction will result in the same economic benefit, the items so reduced will be reduced pro rata (the “Pro Rata Reduction Method”).

Notwithstanding the foregoing, if the Reduction Method or the Pro Rata Reduction Method would result in any portion of the Payment being subject to taxes pursuant to Section 409A of the Code that would not otherwise be subject to taxes pursuant to Section 409A of the Code, then the Reduction Method and/or the Pro Rata Reduction

Non-Employee Director Stock Option Grant Package

Method, as the case may be, shall be modified so as to avoid the imposition of taxes pursuant to Section 409A of the Code as follows: (A) as a first priority, the modification shall preserve to the greatest extent possible, the greatest economic benefit for you as determined on an after-tax basis; (B) as a second priority, Payments that are contingent on future events (e.g., being terminated without cause), shall be reduced (or eliminated) before Payments that are not contingent on future events; and (C) as a third priority, Payments that are “deferred compensation” within the meaning of Section 409A of the Code shall be reduced (or eliminated) before Payments that are not deferred compensation within the meaning of Section 409A of the Code.

Unless you and the Company agree on an alternative accounting firm, the accounting firm engaged by the Company for general tax compliance purposes as of the day prior to the effective date of the change of control transaction triggering the Payment shall perform the foregoing calculations. If the accounting firm so engaged by the Company is serving as accountant or auditor for the individual, entity or group effecting the change of control transaction, the Company shall appoint a nationally recognized accounting firm to make the determinations required hereunder. The Company shall bear all expenses with respect to the determinations by such accounting firm required to be made hereunder. The Company shall use commercially reasonable efforts to cause the accounting firm engaged to make the determinations hereunder to provide its calculations, together with detailed supporting documentation, to you and the Company within fifteen (15) calendar days after the date on which your right to a 280G Payment becomes reasonably likely to occur (if requested at that time by you or the Company) or such other time as requested by you or the Company.

If you receive a Payment for which the Reduced Amount was determined pursuant to clause (x) of the first paragraph of this Section 2(b) and the Internal Revenue Service determines thereafter that some portion of the Payment is subject to the Excise Tax, you shall promptly return to the Company a sufficient amount of the Payment (after reduction pursuant to clause (x) of the first paragraph of this Section 2(b)) so that no portion of the remaining Payment is subject to the Excise Tax. For the avoidance of doubt, if the Reduced Amount was determined pursuant to clause (y) in the first paragraph of this Section 2(b), you shall have no obligation to return any portion of the Payment pursuant to the preceding sentence.

3. EXERCISE.

(a) You may generally exercise the vested portion of your Option for whole shares of Common Stock at any time during its term by delivery of payment of the exercise price and other required documentation to the Plan Administrator in accordance with the exercise procedures established by the Plan Administrator, which may include an electronic submission. Please review Sections 4(i), 4(j) and 7(a)(v) of the Plan, which may restrict or prohibit your ability to exercise your Option during certain periods.

(b) To the extent permitted by Applicable Law, you may pay your Option exercise price as follows:

(i) cash, check, bank draft or money order;

(iii) subject to Company and/or Committee consent at the time of exercise, by delivery of previously owned shares of Common Stock as further described in Section 4(c)(iii) of the Plan; or

4. TERM. You may not exercise your Option before the commencement of its term or after its term expires. The term of your Option commences on the Date of Grant and expires upon the earliest of the following:

(a) immediately upon the termination of your Continuous Service for Cause;

Non-Employee Director Stock Option Grant Package

(b) three months after the termination of your Continuous Service for any reason other than Cause, Disability or death;

(d) 18 months after your death if you die during your Continuous Service;

(e) immediately upon a Corporate Transaction if the Board has determined that the Option will terminate in connection with a Corporate Transaction,

(f) the Expiration Date indicated in your Grant Notice; or

(g) the day before the 10th anniversary of the Date of Grant.

Notwithstanding the foregoing, if you die during the period provided in Section 4(b) or 4(c) above, the term of your Option shall not expire until the earlier of (i) eighteen months after your death, (ii) upon any termination of the Option in connection with a Corporate Transaction, (iii) the Expiration Date indicated in your Grant Notice, or (iv) the day before the tenth anniversary of the Date of Grant. Additionally, the Post-Termination Exercise Period of your Option may be extended as provided in Section 4(i) of the Plan.

5. TAXES. You expressly acknowledge and agree that you (and not the Company) shall be fully responsible for satisfying your own tax liability arising from or due in connection with the Option, its exercise or the disposition of any shares of Common Stock acquired upon exercise of the Option. The Company shall have no liability or obligation relating to the foregoing.

7. CORPORATE TRANSACTION. Your Option is subject to the terms of any agreement governing a Corporate Transaction involving the Company, including, without limitation, a provision for the appointment of a stockholder representative that is authorized to act on your behalf with respect to any escrow, indemnities and any contingent consideration.

Non-Employee Director Stock Option Grant Package

* * * *

Non-Employee Director Stock Option Grant Package

ATTACHMENT II

AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN

Non-Employee Director Stock Option Grant Package

ATTACHMENT III

NOTICE OF EXERCISE

Non-Employee Director Stock Option Grant Package

ACUMEN PHARMACEUTICALS, INC.

(AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN)

NOTICE OF EXERCISE

ACUMEN PHARMACEUTICALS, INC.

1210-1220 Washington Street, Suite 210

Newton, Massachusetts 02465

Date of Exercise:

Type of option:

Nonstatutory

Date of Grant:

Number of Shares as to which Option is exercised:

Certificates to be issued in name of:

Total exercise price:

Cash, check, bank draft or money order delivered herewith:

Value of Shares delivered herewith:

Regulation T Program (cashless exercise)

Value of Shares pursuant to net exercise:

By this exercise, I agree (i) to provide such additional documents as you may require pursuant to the terms of the Plan and (ii) to satisfy the tax obligations, if any, relating to the exercise of this Option as set forth in the Option Agreement.

Very truly yours,

Employee Restricted Stock Unit Grant Package

ACUMEN PHARMACEUTICALS, INC.

RSU AWARD GRANT NOTICE

(AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN)

Acumen Pharmaceuticals, Inc. (the “Company”), has awarded to you (the “Participant”) the number of restricted stock units specified and on the terms set forth below in consideration of your services (the “RSU Award”). Your RSU Award is subject to all of the terms and conditions as set forth herein and in the Company’s Amended & Restated 2021 Equity Incentive Plan (the “Plan”) and the Award Agreement (the “Agreement”), which are attached hereto and incorporated herein in their entirety. Capitalized terms not explicitly defined herein but defined in the Plan or the Agreement shall have the meanings set forth in the Plan or the Agreement.

Participant:

Date of Grant:

Vesting Commencement Date:

Number of Restricted Stock Units:



Vesting Schedule:						[●]. Notwithstanding the foregoing, vesting shall terminate upon the Participant’s termination of Continuous Service.

Issuance Schedule:						One share of Common Stock will be issued for each restricted stock unit which vests at the time set forth in Section 5 of the Agreement.

Participant Acknowledgements: By your signature below or by electronic acceptance or authentication in a form authorized by the Company, you understand and agree that:

•The RSU Award is governed by this RSU Award Grant Notice (the “Grant Notice”), and the provisions of the Plan and the Agreement, all of which are made a part of this document. Unless otherwise provided in the Plan, this Grant Notice and the Agreement (together, the “RSU Award Agreement”) may not be modified, amended or revised except in a writing signed by you and a duly authorized officer of the Company.

•You have read and are familiar with the provisions of the Plan, the RSU Award Agreement and the Prospectus. In the event of any conflict between the provisions in the RSU Award Agreement, or the Prospectus and the terms of the Plan, the terms of the Plan shall control.

•The RSU Award Agreement sets forth the entire understanding between you and the Company regarding the acquisition of Common Stock and supersedes all prior oral and written agreements, promises and/or representations on that subject with the exception of (i) other equity awards previously granted to you, and (ii) any written employment agreement, offer letter, severance agreement, written severance plan or policy, or other written agreement between the Company and you in each case that specifies the terms that should govern this RSU Award.

Employee Restricted Stock Unit Grant Package

ACUMEN PHARMACEUTICALS, INC.

PARTICIPANT:

By:

Signature

Title:

Date:

ATTACHMENTS: RSU Award Agreement, Amended & Restated 2021 Equity Incentive Plan

Employee Restricted Stock Unit Grant Package

ACUMEN PHARMACEUTICALS, INC.

AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN

AWARD AGREEMENT (RSU AWARD)

As reflected by your Restricted Stock Unit Grant Notice (“Grant Notice”), Acumen Pharmaceuticals, Inc. (the “Company”) has granted you a RSU Award under its Amended & Restated 2021 Equity Incentive Plan (the “Plan”) for the number of restricted stock units as indicated in your Grant Notice (the “RSU Award”). The terms of your RSU Award as specified in this Award Agreement for your RSU Award (the “Agreement”) and the Grant Notice constitute your “RSU Award Agreement”. Defined terms not explicitly defined in this Agreement but defined in the Grant Notice or the Plan shall have the same definitions as in the Grant Notice or Plan, as applicable.

The general terms applicable to your RSU Award are as follows:

1. GOVERNING PLAN DOCUMENT. Your RSU Award is subject to all the provisions of the Plan, including but not limited to the provisions in:

(a) Section 6 of the Plan regarding the impact of a Capitalization Adjustment, dissolution, liquidation, or Corporate Transaction on your RSU Award;

(b) Section 9(e) of the Plan regarding the Company’s retained rights to terminate your Continuous Service notwithstanding the grant of the RSU Award; and

Your RSU Award is further subject to all interpretations, amendments, rules and regulations, which may from time to time be promulgated and adopted pursuant to the Plan. In the event of any conflict between the RSU Award Agreement and the provisions of the Plan, the provisions of the Plan shall control.

2. GRANT OF THE RSU AWARD. This RSU Award represents your right to be issued on a future date the number of shares of the Company’s Common Stock that is equal to the number of restricted stock units indicated in the Grant Notice as modified to reflect any Capitalization Adjustment and subject to your satisfaction of the vesting conditions set forth therein (the “Restricted Stock Units”). Any additional Restricted Stock Units that become subject to the RSU Award pursuant to Capitalization Adjustments as set forth in the Plan and the provisions of Section 3 below, if any, shall be subject, in a manner determined by the Board, to the same forfeiture restrictions, restrictions on transferability, and time and manner of delivery as applicable to the other Restricted Stock Units covered by your RSU Award.

3. DIVIDENDS. You shall receive no benefit or adjustment to your RSU Award with respect to any cash dividend, stock dividend or other distribution that does not result from a Capitalization Adjustment as provided in the Plan; provided, however, that this sentence shall not apply with respect to any shares of Common Stock that are delivered to you in connection with your RSU Award after such shares have been delivered to you.

4. WITHHOLDING OBLIGATIONS. As further provided in Section 8 of the Plan, you hereby authorize withholding from payroll and any other amounts payable to you, and otherwise agree to make adequate provision for, any sums required to satisfy the federal, state, local and foreign tax withholding obligations, if any, which arise in connection with your RSU Award (the “Withholding Obligation”) in accordance with the withholding procedures established by the Company. Unless the Withholding Obligation is satisfied, the Company shall have no obligation to deliver to you any Common Stock in respect of the RSU Award. In the event the Withholding Obligation of the Company arises prior to the delivery to you of Common Stock or it is determined after the delivery of Common Stock to you that the amount of the Withholding Obligation was greater than the amount withheld by the Company, you agree to indemnify and hold the Company harmless from any failure by the Company to withhold the proper amount.

Employee Restricted Stock Unit Grant Package

5. DATE OF ISSUANCE.

(a) The issuance of shares in respect of the Restricted Stock Units is intended to comply with Treasury Regulations Section 1.409A-1(b)(4) and will be construed and administered in such a manner. Subject to the satisfaction of the Withholding Obligation, if any, in the event one or more Restricted Stock Units vests, the Company shall issue to you one (1) share of Common Stock for each Restricted Stock Unit that vests on the applicable vesting date(s) (subject to any adjustment under Section 3 above, and subject to any different provisions in the Grant Notice). Each issuance date determined by this paragraph is referred to as an “Original Issuance Date.”

(b) If the Original Issuance Date falls on a date that is not a business day, delivery shall instead occur on the next following business day. In addition, if:

(i) the Original Issuance Date does not occur (1) during an “open window period” applicable to you, as determined by the Company in accordance with the Company’s then-effective policy on trading in Company securities, or (2) on a date when you are otherwise permitted to sell shares of Common Stock on an established stock exchange or stock market (including but not limited to under a previously established written trading plan that meets the requirements of Rule 10b5-1 under the Exchange Act and was entered into in compliance with the Company’s policies (a “10b5-1 Arrangement”)), and

(ii) either (1) a Withholding Obligation does not apply, or (2) the Company decides, prior to the Original Issuance Date, (A) not to satisfy the Withholding Obligation by withholding shares of Common Stock from the shares otherwise due, on the Original Issuance Date, to you under this Award, and (B) not to permit you to enter into a “same day sale” commitment with a broker-dealer (including but not limited to a commitment under a 10b5-1 Arrangement) and (C) not to permit you to pay your Withholding Obligation in cash,

(iii) then the shares that would otherwise be issued to you on the Original Issuance Date will not be delivered on such Original Issuance Date and will instead be delivered on the first business day when you are not prohibited from selling shares of the Company’s Common Stock in the open public market, but in no event later than December 31 of the calendar year in which the Original Issuance Date occurs (that is, the last day of your taxable year in which the Original Issuance Date occurs), or, if and only if permitted in a manner that complies with Treasury Regulations Section 1.409A-1(b)(4), no later than the date that is the 15th day of the third calendar month of the applicable year following the year in which the shares of Common Stock under this Award are no longer subject to a “substantial risk of forfeiture” within the meaning of Treasury Regulations Section 1.409A-1(d).

(d) In addition and notwithstanding the foregoing, no shares of Common Stock issuable to you under this Section 5 as a result of the vesting of one or more RSUs will be delivered to you until any filings that may be required pursuant to the Hart-Scott-Rodino (“HSR”) Act in connection with the issuance of such shares have been filed and any required waiting period under the HSR Act has expired or been terminated (any such filings and/or waiting period required pursuant to HSR, the “HSR Requirements”). If the HSR Requirements apply to the issuance of any shares of Common Stock issuable to you under this Section 5 upon vesting of one or more RSUs, such shares will not be issued on the Original Issuance Date and will instead be issued on the first business day on or following the date when all such HSR Requirements are satisfied and when you are permitted to sell shares of Common Stock on an established stock exchange or stock market, as determined by the Company in accordance with the Company’s then-effective policy on trading in Company securities. Notwithstanding the foregoing, the issuance date for any shares of Common Stock delayed under this Section 5(d) shall in no event be later than December 31 of the calendar year in which the Original Issuance Date occurs (that is, the last day of your taxable year in which the Original Issuance Date occurs), unless a later issuance date is permitted without incurring adverse tax consequences under Section 409A or other Applicable Laws.

6. TRANSFERABILITY. Except as otherwise provided in the Plan, your RSU Award is not transferable, except by will or by the applicable laws of descent and distribution.

Employee Restricted Stock Unit Grant Package

7. CORPORATE TRANSACTION. Your RSU Award is subject to the terms of any agreement governing a Corporate Transaction involving the Company, including, without limitation, a provision for the appointment of a stockholder representative that is authorized to act on your behalf with respect to any escrow, indemnities and any contingent consideration.

8. NO LIABILITY FOR TAXES. As a condition to accepting the RSU Award, you hereby (a) agree to not make any claim against the Company, or any of its Officers, Directors, Employees or Affiliates related to tax liabilities arising from the RSU Award or other Company compensation and (b) acknowledge that you were advised to consult with your own personal tax, financial and other legal advisors regarding the tax consequences of the RSU Award and have either done so or knowingly and voluntarily declined to do so.

9. SEVERABILITY. If any part of this Agreement or the Plan is declared by any court or governmental authority to be unlawful or invalid, such unlawfulness or invalidity will not invalidate any portion of this Agreement or the Plan not declared to be unlawful or invalid. Any Section of this Agreement (or part of such a Section) so declared to be unlawful or invalid will, if possible, be construed in a manner which will give effect to the terms of such Section or part of a Section to the fullest extent possible while remaining lawful and valid.

11. QUESTIONS. If you have questions regarding these or any other terms and conditions applicable to your RSU Award, including a summary of the applicable federal income tax consequences please see the Prospectus.

Non-Employee Director Restricted Stock Unit Grant Package

ACUMEN PHARMACEUTICALS, INC.

RSU AWARD GRANT NOTICE

(AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN)

Participant:

Date of Grant:

Vesting Commencement Date:

Number of Restricted Stock Units:



Vesting Schedule:						Subject to the Participant’s Continuous Service through the vesting date, the Award will vest as follows, subject to the potential vesting acceleration described in Section 3 of the Award Agreement: [●].

Issuance Schedule:						One share of Common Stock will be issued for each restricted stock unit which vests at the time set forth in Section 3 of the Agreement.

Participant Acknowledgements: By your signature below or by electronic acceptance or authentication in a form authorized by the Company, you understand and agree that:

•You have read and are familiar with the provisions of the Plan, the Agreement and the Prospectus. In the event of any conflict between the provisions in the Agreement, or the Prospectus and the terms of the Plan, the terms of the Plan shall control.

•The Agreement sets forth the entire understanding between you and the Company regarding the acquisition of Common Stock and supersedes all prior oral and written agreements, promises and/or representations on that subject with the exception of (i) other equity awards previously granted to you, and (ii) any written employment agreement, offer letter, severance agreement, written severance plan or policy, or other written agreement between the Company and you in each case that specifies the terms that should govern this RSU Award.

Non-Employee Director Restricted Stock Unit Grant Package

ACUMEN PHARMACEUTICALS, INC.

PARTICIPANT:

By:

Signature

Title:

Date:

ATTACHMENTS: RSU Award Agreement, Amended & Restated 2021 Equity Incentive Plan

Non-Employee Director Restricted Stock Unit Grant Package

ACUMEN PHARMACEUTICALS, INC.

AMENDED & RESTATED 2021 EQUITY INCENTIVE PLAN

AWARD AGREEMENT (RSU AWARD)

(Non-Employee Directors)

The general terms applicable to your RSU Award are as follows:

1. GOVERNING PLAN DOCUMENT. Your RSU Award is subject to all the provisions of the Plan, including but not limited to the provisions in:

(a) Section 6 of the Plan regarding the impact of a Capitalization Adjustment, dissolution, liquidation, or Corporate Transaction on your RSU Award;

(b) Section 9(e) of the Plan regarding the Company’s retained rights to terminate your Continuous Service notwithstanding the grant of the RSU Award; and

2. GRANT OF THE RSU AWARD. This RSU Award represents your right to be issued on a future date the number of shares of the Company’s Common Stock that is equal to the number of restricted stock units indicated in the Grant Notice as modified to reflect any Capitalization Adjustment and subject to your satisfaction of the vesting conditions set forth in the Grant Notice (the “Restricted Stock Units”). Any additional Restricted Stock Units that become subject to the RSU Award pursuant to Capitalization Adjustments as set forth in the Plan and the provisions of Section 4 below, if any, shall be subject, in a manner determined by the Board, to the same forfeiture restrictions, restrictions on transferability, and time and manner of delivery as applicable to the other Restricted Stock Units covered by your RSU Award.

3. Vesting. The Restricted Stock Units will vest as provided in your Grant Notice, subject to the provisions contained herein and the terms of the Plan. Vesting will cease upon the termination of your Continuous Service. Notwithstanding the foregoing, if a Change in Control occurs and your Continuous Service has not terminated as of immediately prior to such Change in Control, then the vesting of your Restricted Stock Units will be accelerated in full upon such Change in Control.

4. DIVIDENDS. You shall receive no benefit or adjustment to your RSU Award with respect to any cash dividend, stock dividend or other distribution that does not result from a Capitalization Adjustment as provided in the Plan; provided, however, that this sentence shall not apply with respect to any shares of Common Stock that are delivered to you in connection with your RSU Award after such shares have been delivered to you.

5. Taxes. You expressly acknowledge and agree that you (and not the Company) shall be fully responsible for satisfying your own tax liability arising from or due in connection with the grant, vesting and/or settlement of the Restricted Stock Units and the delivery of any shares of Common Stock under this RSU Award. The Company shall have no liability or obligation relating to the foregoing.

Non-Employee Director Restricted Stock Unit Grant Package

6. DATE OF ISSUANCE.

(a) The issuance of shares in respect of the Restricted Stock Units is intended to comply with Treasury Regulations Section 1.409A-1(b)(4) and will be construed and administered in such a manner. In the event one or more Restricted Stock Units vests, the Company shall issue to you one (1) share of Common Stock for each Restricted Stock Unit that vests on the applicable vesting date(s) (subject to any adjustment under Section 4 above, and subject to any different provisions in the Grant Notice). Each issuance date determined by this paragraph is referred to as an “Original Issuance Date.”

(b) If the Original Issuance Date falls on a date that is not a business day, delivery shall instead occur on the next following business day. In addition, if:

(ii) then the shares that would otherwise be issued to you on the Original Issuance Date will not be delivered on such Original Issuance Date and will instead be delivered on the first business day when you are not prohibited from selling shares of the Company’s Common Stock in the open public market, but in no event later than December 31 of the calendar year in which the Original Issuance Date occurs (that is, the last day of your taxable year in which the Original Issuance Date occurs), or, if and only if permitted in a manner that complies with Treasury Regulations Section 1.409A-1(b)(4), no later than the date that is the 15th day of the third calendar month of the applicable year following the year in which the shares of Common Stock under this Award are no longer subject to a “substantial risk of forfeiture” within the meaning of Treasury Regulations Section 1.409A-1(d).

(d) In addition and notwithstanding the foregoing, no shares of Common Stock issuable to you under this Section 6 as a result of the vesting of one or more RSUs will be delivered to you until any filings that may be required pursuant to the Hart-Scott-Rodino (“HSR”) Act in connection with the issuance of such shares have been filed and any required waiting period under the HSR Act has expired or been terminated (any such filings and/or waiting period required pursuant to HSR, the “HSR Requirements”). If the HSR Requirements apply to the issuance of any shares of Common Stock issuable to you under this Section 6 upon vesting of one or more RSUs, such shares will not be issued on the Original Issuance Date and will instead be issued on the first business day on or following the date when all such HSR Requirements are satisfied and when you are permitted to sell shares of Common Stock on an established stock exchange or stock market, as determined by the Company in accordance with the Company’s then-effective policy on trading in Company securities. Notwithstanding the foregoing, the issuance date for any shares of Common Stock delayed under this Section 6(d) shall in no event be later than December 31 of the calendar year in which the Original Issuance Date occurs (that is, the last day of your taxable year in which the Original Issuance Date occurs), unless a later issuance date is permitted without incurring adverse tax consequences under Section 409A or other Applicable Laws.

7. TRANSFERABILITY. Except as otherwise provided in the Plan, your RSU Award is not transferable, except by will or by the applicable laws of descent and distribution.

8. CORPORATE TRANSACTION. Your RSU Award is subject to the terms of any agreement governing a Corporate Transaction involving the Company, including, without limitation, a provision for the appointment of a stockholder representative that is authorized to act on your behalf with respect to any escrow, indemnities and any contingent consideration.

Non-Employee Director Restricted Stock Unit Grant Package

9. NO LIABILITY FOR TAXES. As a condition to accepting the RSU Award, you hereby (a) agree to not make any claim against the Company, or any of its Officers, Directors, Employees or Affiliates related to tax liabilities arising from the RSU Award or other Company compensation and (b) acknowledge that you were advised to consult with your own personal tax, financial and other legal advisors regarding the tax consequences of the RSU Award and have either done so or knowingly and voluntarily declined to do so.

10. SEVERABILITY. If any part of this Agreement or the Plan is declared by any court or governmental authority to be unlawful or invalid, such unlawfulness or invalidity will not invalidate any portion of this Agreement or the Plan not declared to be unlawful or invalid. Any Section of this Agreement (or part of such a Section) so declared to be unlawful or invalid will, if possible, be construed in a manner which will give effect to the terms of such Section or part of a Section to the fullest extent possible while remaining lawful and valid.

11. OTHER DOCUMENTS. You hereby acknowledge receipt of or the right to receive a document providing the information required by Rule 428(b)(1) promulgated under the Securities Act, which includes the Prospectus. In addition, you acknowledge receipt of the Company’s Trading Policy.

12. QUESTIONS. If you have questions regarding these or any other terms and conditions applicable to your RSU Award, including a summary of the applicable federal income tax consequences please see the Prospectus.

Document

Exhibit 31.1

CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES EXCHANGE ACT OF 1934,

AS ADOPTED PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Daniel O’Connell, certify that:

1.I have reviewed this Form 10-Q of Acumen Pharmaceuticals, Inc.;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

(a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c)Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d)Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.


Date: August 12, 2026	By:	/s/ Daniel O’Connell
		Daniel O’Connell
		Chief Executive Officer (Principal Executive Officer)

Document

Exhibit 31.2

CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES EXCHANGE ACT OF 1934,

AS ADOPTED PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Matthew Zuga, certify that:

1.I have reviewed this Form 10-Q of Acumen Pharmaceuticals, Inc.;

(b)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.


Date: August 12, 2026	By:	/s/ Matthew Zuga
		Matthew Zuga
		Chief Financial Officer and Chief Business Officer (Principal Financial Officer and Principal Accounting Officer)

Document

Exhibit 32.1

CERTIFICATION OF PERIODIC FINANCIAL REPORTS PURSUANT TO

18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report on Form 10-Q of Acumen Pharmaceuticals, Inc. (the “Company”) for the period ended June 30, 2026 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Daniel O’Connell, President and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

1.The Report fully complies with the requirements of Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.


Date: August 12, 2026	By:	/s/ Daniel O’Connell
		Daniel O’Connell
		Chief Executive Officer (Principal Executive Officer)

Document

Exhibit 32.2

CERTIFICATION OF PERIODIC FINANCIAL REPORTS PURSUANT TO

18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report on Form 10-Q of Acumen Pharmaceuticals, Inc. (the “Company”) for the period ended June 30, 2026 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Matthew Zuga, Chief Financial Officer and Chief Business Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

1.The Report fully complies with the requirements of Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.


Date: August 12, 2026	By:	/s/ Matthew Zuga
		Matthew Zuga
		Chief Financial Officer and Chief Business Officer (Principal Financial Officer and Principal Accounting Officer)