Acumen Pharmaceuticals, Inc. 10-Q

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 34 Table of Contents “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. 35 Table of Contents 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) 36