<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2019-08-19</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001347178</issuerCik>
        <issuerName>Vanda Pharmaceuticals Inc.</issuerName>
        <issuerTradingSymbol>VNDA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001785894</rptOwnerCik>
            <rptOwnerName>Jones Aranthan II</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O VANDA PHARMACEUTICALS INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2200 PENNSYLVANIA AVENUE, SUITE 300E</rptOwnerStreet2>
            <rptOwnerCity>WASHINGTON</rptOwnerCity>
            <rptOwnerState>DC</rptOwnerState>
            <rptOwnerZipCode>20037</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Corp. Affairs Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>60000</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>12.27</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2029-07-24</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>60000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of common stock underlying a time-based restricted stock unit award (&quot;RSU&quot;). The RSU vests in four (4) equal annual installments beginning July 25, 2020, provided the Reporting Person remains continuously employed by the Issuer through each annual vesting date. Vested shares will be delivered on the First Permissible Trading Day (as defined in the RSU Agreement) that occurs on or after the day when the RSUs vest.</footnote>
        <footnote id="F2">The option vests and becomes exercisable with respect to 1/4 of the shares subject to the option on July 25, 2020 (the &quot;Initial Vesting Date&quot;), provided the Reporting Person remains continuously employed by the issuer through the Initial Vesting Date, and with respect to the remaining 3/4 of the shares in 36 equal monthly installments beginning August 25, 2020, provided the Reporting Person remains continuously employed by the issuer through each monthly vesting date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Aranthan S. Jones II</signatureName>
        <signatureDate>2019-08-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
