<SEC-DOCUMENT>0001193125-18-136751-index.html : 20180427
<SEC-HEADER>0001193125-18-136751.hdr.sgml : 20180427
<ACCEPTANCE-DATETIME>20180427082003
ACCESSION NUMBER:		0001193125-18-136751
CONFORMED SUBMISSION TYPE:	DEF 14A
PUBLIC DOCUMENT COUNT:		7
CONFORMED PERIOD OF REPORT:	20180605
FILED AS OF DATE:		20180427
DATE AS OF CHANGE:		20180427
EFFECTIVENESS DATE:		20180427

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:		DEF 14A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38266
		FILM NUMBER:		18781089

	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
</SEC-HEADER>
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Document 1 - file: d494847ddef14a.htm

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Document 3 - file: g494847g05k11.jpg

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Document 4 - file: g494847g25f08.jpg

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Document 5 - file: g494847pc1a.jpg

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Document 6 - file: g494847pc2a.jpg

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Document 7 - file: g494847pc2b.jpg

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