Exhibit 32.1
CERTIFICATIONS OF
PRINCIPAL EXECUTIVE OFFICER AND PRINCIPAL FINANCIAL OFFICER
PURSUANT TO 18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
Pursuant to the requirement set forth in Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. §1350), John Celebi, President, Chief Executive Officer and Principal Financial Officer of Sensei Biotherapeutics, Inc. (the “Company”), and Josiah Craver, Senior Vice President of Finance of the Company, each hereby certifies that, to the best of his knowledge:
IN WITNESS WHEREOF, the undersigned has set his hand hereto as of the 6th day of May 2025.
/s/ John Celebi  | 
     
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     /s/ Josiah Craver  | 
    
John Celebi  | 
     
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     Josiah Craver  | 
    
President and Chief Executive Officer  | 
     
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     Senior Vice President of Finance (Principal Financial Officer and Accounting Officer)  | 
    
* This certification accompanies the Form 10-Q to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing