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ACCESSION NUMBER: 0001193125-26-374702
CONFORMED SUBMISSION TYPE: S-3
PUBLIC DOCUMENT COUNT: 21
FILED AS OF DATE: 20260828
DATE AS OF CHANGE: 20260828

FILER:

 COMPANY DATA: 
 COMPANY CONFORMED NAME: Spero Therapeutics, Inc.
 CENTRAL INDEX KEY: 0001701108
 STANDARD INDUSTRIAL CLASSIFICATION: PHARMACEUTICAL PREPARATIONS [2834]
 ORGANIZATION NAME: 03 Life Sciences
 EIN: 000000000
 STATE OF INCORPORATION: DE
 FISCAL YEAR END: 1231

 FILING VALUES:
 FORM TYPE: S-3
 SEC ACT: 1933 Act
 SEC FILE NUMBER: 333-298641
 FILM NUMBER: 261341317

 BUSINESS ADDRESS: 
 STREET 1: 675 MASSACHUSETTS AVENUE
 STREET 2: 14TH FLOOR
 CITY: CAMBRIDGE
 STATE: MA
 ZIP: 02139
 BUSINESS PHONE: 857-242-1600

 MAIL ADDRESS: 
 STREET 1: 675 MASSACHUSETTS AVENUE
 STREET 2: 14TH FLOOR
 CITY: CAMBRIDGE
 STATE: MA
 ZIP: 02139

 FORMER COMPANY: 
 FORMER CONFORMED NAME: Spero Therapeutics, LLC
 DATE OF NAME CHANGE: 20170316
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