<SEC-DOCUMENT>0000950123-17-008682-index.html : 20171006
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<ACCEPTANCE-DATETIME>20170929101106
<PRIVATE-TO-PUBLIC>
ACCESSION NUMBER:		0000950123-17-008682
CONFORMED SUBMISSION TYPE:	DRS/A
PUBLIC DOCUMENT COUNT:		15
FILED AS OF DATE:		20170929
<PUBLIC-REL-DATE>20171006
DATE AS OF CHANGE:		20170929

FILER:

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

	FILING VALUES:
		FORM TYPE:		DRS/A
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	377-01690
		FILM NUMBER:		171109435

	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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