<SEC-DOCUMENT>0001591986-21-000012-index.html : 20210901
<SEC-HEADER>0001591986-21-000012.hdr.sgml : 20210901
<ACCEPTANCE-DATETIME>20210901174257
ACCESSION NUMBER:		0001591986-21-000012
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210830
FILED AS OF DATE:		20210901
DATE AS OF CHANGE:		20210901

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Aquilo Capital, L.P.
		CENTRAL INDEX KEY:			0001491371
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38266
		FILM NUMBER:		211231173

	BUSINESS ADDRESS:	
		STREET 1:		ONE LETTERMAN DRIVE, SUITE D4900
		STREET 2:		BUILDING D, THE PRESIDIO
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94129
		BUSINESS PHONE:		(415) 635-0141

	MAIL ADDRESS:	
		STREET 1:		ONE LETTERMAN DRIVE, SUITE D4900
		STREET 2:		BUILDING D, THE PRESIDIO
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94129

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Aquilo Capital Management, LLC
		CENTRAL INDEX KEY:			0001591986
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38266
		FILM NUMBER:		211231174

	BUSINESS ADDRESS:	
		STREET 1:		ONE LETTERMAN DRIVE
		STREET 2:		SUITE D4900, BUILDING D
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94129
		BUSINESS PHONE:		415-635-0140

	MAIL ADDRESS:	
		STREET 1:		ONE LETTERMAN DRIVE
		STREET 2:		SUITE D4900, BUILDING D
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94129

	FORMER NAME:	
		FORMER CONFORMED NAME:	Aquilo Capital Managment, LLC
		DATE OF NAME CHANGE:	20131114

ISSUER:		

	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

	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: primary_doc.html

Document 1 - RAW XML: primary_doc.xml

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