<SEC-DOCUMENT>0001193125-18-219722-index.html : 20180717
<SEC-HEADER>0001193125-18-219722.hdr.sgml : 20180717
<ACCEPTANCE-DATETIME>20180717163137
ACCESSION NUMBER:		0001193125-18-219722
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20180717
ITEM INFORMATION:		Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20180717
DATE AS OF CHANGE:		20180717

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:		18956798

	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>d541709d8k.htm
<DESCRIPTION>8-K
<TEXT>
Document 1 - file: d541709d8k.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-3.1
<SEQUENCE>2
<FILENAME>d541709dex31.htm
<DESCRIPTION>EX-3.1
<TEXT>
Document 2 - file: d541709dex31.htm

</DOCUMENT>
</SEC-DOCUMENT>