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    <issuer>
        <issuerCik>0001633932</issuerCik>
        <issuerName>ESSA Pharma Inc.</issuerName>
        <issuerTradingSymbol>EPIX</issuerTradingSymbol>
    </issuer>

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            <rptOwnerCik>0001273885</rptOwnerCik>
            <rptOwnerName>BERGER FRANKLIN M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ESSA PHARMA INC.</rptOwnerStreet1>
            <rptOwnerStreet2>999 WEST BROADWAY, SUITE 720</rptOwnerStreet2>
            <rptOwnerCity>VANCOUVER</rptOwnerCity>
            <rptOwnerState>A1</rptOwnerState>
            <rptOwnerZipCode>V5Z 1K5</rptOwnerZipCode>
            <rptOwnerStateDescription>BRITISH COLUMBIA, CANADA</rptOwnerStateDescription>
        </reportingOwnerAddress>
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            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
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    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Franklin Berger</signatureName>
        <signatureDate>2023-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
