<SEC-DOCUMENT>0001209191-18-037313.txt : 20180612
<SEC-HEADER>0001209191-18-037313.hdr.sgml : 20180612
<ACCEPTANCE-DATETIME>20180612184817
ACCESSION NUMBER:		0001209191-18-037313
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180529
FILED AS OF DATE:		20180612
DATE AS OF CHANGE:		20180612

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SELICK HAROLD E
		CENTRAL INDEX KEY:			0001287233

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37852
		FILM NUMBER:		18895551

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Protagonist Therapeutics, Inc
		CENTRAL INDEX KEY:			0001377121
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				980505495
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		7707 GATEWAY BLVD., SUITE 140
		CITY:			NEWARK
		STATE:			CA
		ZIP:			94560-1160
		BUSINESS PHONE:		(510) 474-0170

	MAIL ADDRESS:	
		STREET 1:		7707 GATEWAY BLVD., SUITE 140
		CITY:			NEWARK
		STATE:			CA
		ZIP:			94560-1160

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Protagonist Therapeutics Inc
		DATE OF NAME CHANGE:	20130605

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Protagonist Inc
		DATE OF NAME CHANGE:	20061002
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-05-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001377121</issuerCik>
        <issuerName>Protagonist Therapeutics, Inc</issuerName>
        <issuerTradingSymbol>PTGX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001287233</rptOwnerCik>
            <rptOwnerName>SELICK HAROLD E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PROTAGONIST THERAPEUTICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>7707 GATEWAY BLVD., SUITE 140</rptOwnerStreet2>
            <rptOwnerCity>NEWARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94560</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.98</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-05-29</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>12000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2028-05-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The shares subject to this option shall vest at the earlier on (i) May 29, 2019, or (ii) the date of the 2019 Annual Meeting of stockholders of the Issuer, subject to the non-employee director's continuous service with the Issuer through such dates. The shares subject to this option will vest in full upon completion of a Change in Control (as defined in the Issuer's 2016 Equity Incentive Plan).</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Thomas P. O'Neil, Attorney-in-Fact</signatureName>
        <signatureDate>2018-06-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
