<SEC-DOCUMENT>0000899243-21-000118.txt : 20210104
<SEC-HEADER>0000899243-21-000118.hdr.sgml : 20210104
<ACCEPTANCE-DATETIME>20210104170007
ACCESSION NUMBER:		0000899243-21-000118
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20201230
FILED AS OF DATE:		20210104
DATE AS OF CHANGE:		20210104

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Garg Vipin K
		CENTRAL INDEX KEY:			0001515813

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32587
		FILM NUMBER:		21502515

	MAIL ADDRESS:	
		STREET 1:		4819 EMPEROR BOULEVARD
		STREET 2:		SUITE 400
		CITY:			DURHAM
		STATE:			NC
		ZIP:			27703

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Altimmune, Inc.
		CENTRAL INDEX KEY:			0001326190
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				202726770
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		910 CLOPPER ROAD
		STREET 2:		SUITE 201S
		CITY:			GAITHERSBURG
		STATE:			MD
		ZIP:			20878
		BUSINESS PHONE:		2406541450

	MAIL ADDRESS:	
		STREET 1:		910 CLOPPER ROAD
		STREET 2:		SUITE 201S
		CITY:			GAITHERSBURG
		STATE:			MD
		ZIP:			20878

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PHARMATHENE, INC
		DATE OF NAME CHANGE:	20071016

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HEALTHCARE ACQUISITION CORP
		DATE OF NAME CHANGE:	20050505
</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>2020-12-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001326190</issuerCik>
        <issuerName>Altimmune, Inc.</issuerName>
        <issuerTradingSymbol>ALT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001515813</rptOwnerCik>
            <rptOwnerName>Garg Vipin K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALTIMMUNE, INC., 910 CLOPPER ROAD,</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 201S</rptOwnerStreet2>
            <rptOwnerCity>GAITHERSBURG</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20878</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.0001</value>
            </securityTitle>
            <transactionDate>
                <value>2020-12-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3025</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.30</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>314476</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Vesting transaction: Shares surrendered to the Issuer solely to cover taxes associated with vesting of restricted stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ William Brown, as Attorney-in-Fact</signatureName>
        <signatureDate>2021-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
