10 unchanged sentences
(Exhibit 3.1)
+Added: Certificate of Amendment to the Amended and Restated Certificate of Incorporation of the Registrant
+Added: (Exhibit 3.1)
Amended and Restated Bylaws of the Registrant
(Exhibit 3.1)
+Added: 2026 Stock Incentive Plan
+Added: (Exhibit 99.1)
+Added: Form of Stock Option Agreement under the 2026 Stock Incentive Plan
+Added: Form of Restricted Stock Unit Agreement under the 2026 Stock Incentive Plan
+Added: Exclusive License Agreement, dated July 8, 2026, by and between the Registrant and Innovent Biologics (Suzhou) Co., Ltd.
+Added: and Fortvita Biologics (USA), Inc.
+Added: Note Purchase and Guaranty Agreement dated July 8, 2026, by and between the Spero Holdings SPV, LLC, Spero SPV, LLC and the purchasers party thereto and HCR Spero SPV, LLC, as the purchaser representative for such purchasers
+Added: Royalty and Milestone Payment Interest Purchase and Sale Agreement dated July 8, 2026, by and between Spero SPV, LLC and the purchasers party thereto and HCR Spero SPV, LLC, as the purchaser representative for such purchasers
+Added: Limited Recourse Guaranty dated July 8, 2026, by and between the Registrant and HCR Spero SPV, LLC
+Added: Employment Agreement, dated August 3, 2026 by and between the Registrant and Debra Zack, M.D., PhD
+Added: Termination Agreement, dated August 11, 2026, by and between Registrant and Everest Medicines II Limited
Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
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Cover Page Interactive Data File (embedded within the Inline XBRL document)
+Added: Certain confidential portions of this Exhibit were omitted by means of marking such portions with brackets (“[***]”) because the identified confidential portions (i) are not material and (ii) is the type that the Registrant treats as private or confidential.
* The certification attached as Exhibit 32.1 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.
2 unchanged sentences
SPERO THERAPEUTICS, INC.
+Added: August 12, 2026
/s/ Esther Rajavelu
3 unchanged sentences
Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.