<SEC-DOCUMENT>0001209191-20-039352.txt : 20200630
<SEC-HEADER>0001209191-20-039352.hdr.sgml : 20200630
<ACCEPTANCE-DATETIME>20200629212120
ACCESSION NUMBER:		0001209191-20-039352
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200622
FILED AS OF DATE:		20200629
DATE AS OF CHANGE:		20200629

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mahadevia Ankit
		CENTRAL INDEX KEY:			0001720974

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38266
		FILM NUMBER:		20999937

	MAIL ADDRESS:	
		STREET 1:		C/O SPERO THERAPEUTICS, INC.
		STREET 2:		675 MASSACHUSETTS AVE., 14TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

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>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4 SUBMISSION
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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    <footnotes>
        <footnote id="F1">All transactions reported on this Form 4 were made pursuant to a previously adopted Rule 10b5-1 trading plan. Specifically, the transactions reported herein relate to option exercises and related sales (totaling 17,180 shares).</footnote>
        <footnote id="F2">Amount includes 65,817 shares of common stock held by the Mahadevia-Mehta Family Trust, of which the Reporting Person is a trustee.</footnote>
        <footnote id="F3">All of the option exercises reported herein were made with respect to options granted pursuant to the Company's 2017 Equity Incentive Plan on July 6, 2017 with vesting schedules generally consisting of 25% cliff vesting on specified dates and with the remainder vesting in 36 equal monthly installments thereafter, subject to the Reporting Person's continued service through the applicable vesting date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Ankit Mahadevia</signatureName>
        <signatureDate>2020-06-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
