8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 11, 2024

Sensei Biotherapeutics, Inc.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (240) 243-8000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Securities Exchange Act of 1934:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

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. ☐

Item 5.07 Submission of Matters to a Vote of Security Holders.

On June 11, 2024, Sensei Biotherapeutics, Inc. (the “Company”) held its 2024 annual meeting of stockholders (the “Annual Meeting”). The stockholders considered two proposals, each of which is described in more detail in the Company’s definitive proxy statement filed with the Securities and Exchange Commission on April 29, 2024 (the “Proxy Statement”). Of the 25,080,958 shares outstanding as of the record date, 17,108,258 shares, or 68.21%, were present or represented by proxy at the Annual Meeting. Set forth below are the results of the matters submitted for a vote of stockholders at the Annual Meeting.

Proposal No. 1: Election of three nominees to serve as directors on the Board of Directors until the 2027 annual meeting of stockholders and until their respective successors are elected and qualified. The votes were cast as follows:

All nominees were elected.

Proposal No. 2: Ratification of the appointment of Deloitte & Touche LLP as independent registered public accounting firm for the fiscal year ending December 31, 2024. The votes were cast as follows:

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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 hereunto duly authorized.

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