<SEC-DOCUMENT>0001193125-17-369517-index.html : 20171214
<SEC-HEADER>0001193125-17-369517.hdr.sgml : 20171214
<ACCEPTANCE-DATETIME>20171214162503
ACCESSION NUMBER:		0001193125-17-369517
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		3
CONFORMED PERIOD OF REPORT:	20171214
ITEM INFORMATION:		Results of Operations and Financial Condition
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20171214
DATE AS OF CHANGE:		20171214

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:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38266
		FILM NUMBER:		171256451

	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>
<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>d444395d8k.htm
<DESCRIPTION>8-K
<TEXT>
Document 1 - file: d444395d8k.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>d444395dex991.htm
<DESCRIPTION>EX-99.1
<TEXT>
Document 2 - file: d444395dex991.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>3
<FILENAME>g444395dsp04.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 3 - file: g444395dsp04.jpg

</DOCUMENT>
</SEC-DOCUMENT>