Spero Therapeutics, Inc. 10-Q

Item 5. Other Information. Director and Officer Trading Arrangements None of our directors or officers adopted or terminated a Rule 10b5-1 trading arrangement or a non-Rule 10b5-1 trading arrangement (as such terms are defined in Items 408(a) and 408(c) of Regulation S-K, respectively) during the quarterly period covered by this report. 85 Item 6. Exhibits Exhibit Number Exhibit Description Filed with this Report Incorporated by Reference herein from Form or Schedule Filing Date SEC File / Registration Number 3.1 Amended and Restated Certificate of Incorporation of the Registrant Form 8-K (Exhibit 3.1) 11/6/2017 001-38266 3.2 Certificate of Amendment to the Amended and Restated Certificate of Incorporation of the Registrant Form 8-K (Exhibit 3.1) 8/18/2021 001-38266 3.3 Amended and Restated Bylaws of the Registrant Form 10-Q (Exhibit 3.1) 11/13/2023 001-38266 31 Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 X 32* Certification pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, by Principal Executive Officer and Principal Financial Officer X 101.INS 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 X 101.SCH Inline XBRL Taxonomy Extension Schema Document X 101.CAL Inline XBRL Taxonomy Extension Calculation Linkbase Document X 101.DEF Inline XBRL Taxonomy Extension Definition Linkbase Document X 101.LAB Inline XBRL Taxonomy Extension Label Linkbase Document X 101.PRE Inline XBRL Taxonomy Extension Presentation Linkbase Document X 104 Cover Page Interactive Data File (embedded within the Inline XBRL document) X * The certification attached as Exhibit 32 that accompanies this Quarterly Report on Form 10-Q is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of Spero Therapeutics, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date of this Form 10-Q, irrespective of any general incorporation language contained in such filing. 86 SIGNA TURES 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. SPERO THERAPEUTICS, INC. Date: November 13, 2025 By: /s/ Esther Rajavelu Esther Rajavelu President, Chief Executive Officer, Chief Financial Officer and Treasurer (Principal Executive Officer, Principal Financial Officer and Principal Accounting Officer) 87