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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-04-09</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001781983</issuerCik>
        <issuerName>Aprea Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>APRE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001786141</rptOwnerCik>
            <rptOwnerName>Versant V Luxco S.a r.l.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>15 BOULEVARD F.W. RAIFFEISEN</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>2411 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode>L-2411</rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001589097</rptOwnerCik>
            <rptOwnerName>Versant Venture Capital V, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>15 BOULEVARD F.W. RAIFFEISEN</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>2411 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode>L-2411</rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001589095</rptOwnerCik>
            <rptOwnerName>Versant Affiliates Fund V, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>15 BOULEVARD F.W. RAIFFEISEN</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>2411 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode>L-2411</rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
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            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001589098</rptOwnerCik>
            <rptOwnerName>Versant Ophthalmic Affiliates I, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>15 BOULEVARD F.W. RAIFFEISEN</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>2411 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode>L-2411</rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001612235</rptOwnerCik>
            <rptOwnerName>Versant Venture Capital V (Canada), LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>15 BOULEVARD F.W. RAIFFEISEN</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>2411 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode>L-2411</rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001619298</rptOwnerCik>
            <rptOwnerName>Versant Ventures V, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>15 BOULEVARD F.W. RAIFFEISEN</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>2411 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode>L-2411</rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
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            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001716490</rptOwnerCik>
            <rptOwnerName>Versant Ventures V (Canada), L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>15 BOULEVARD F.W. RAIFFEISEN</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>2411 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode>L-2411</rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-04-09</value>
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            <transactionTimeliness>
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                <transactionPricePerShare>
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                <directOrIndirectOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2020-05-18</value>
            </transactionDate>
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                <sharesOwnedFollowingTransaction>
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                <sharesOwnedFollowingTransaction>
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    <footnotes>
        <footnote id="F1">Represents a pro-rata in-kind distribution of Common Stock of the Issuer by Versant V Luxco S.a.r.l. (&quot;Luxco&quot;)  to its shareholders without consideration.</footnote>
        <footnote id="F2">These Shares are directly held by Versant VI Luxco S.a.r.l. (&quot;Luxco&quot;).</footnote>
        <footnote id="F3">Luxco is majority owned by Versant Venture Capital V, L.P.(&quot;VVC V&quot;) and minority owned by Versant Ophthalmic Affiliates Fund I, L.P. (&quot;VOA&quot;), Versant Affiliates Fund V, L.P. (&quot;VAF V&quot; and together with VVC V and VOA, the &quot;Versant Funds&quot;) and Versant Venture Capital V (Canada) LP (&quot;VVC CAN&quot;). Versant Ventures V, LLC (&quot;VV V&quot;) is the general partner of each of the Versant Funds. Versant Ventures V GP-GP (Canada), Inc. (&quot;VV V CAN GP&quot;) is the general partner of Versant Ventures V (Canada), L.P. (&quot;VV V CAN&quot;), which is the general partner of VVC CAN.</footnote>
        <footnote id="F4">Represents a change in the form of ownership of VVC V by virtue of receipt of shares in the pro-rata in-kind distribution of Common Stock by Luxco.</footnote>
        <footnote id="F5">These securities are held of record by VVC V.  VV  is the sole general partner of VVC V and may be deemed to have voting and investment power over the securities held by VVC V and as a result may be deemed to have beneficial ownership over such securities. VVC V disclaims beneficial ownership of such shares except to the extent of its pecuniary interest therein.</footnote>
        <footnote id="F6">Represents a change in the form of ownership of VAF V by virtue of receipt of shares in the pro-rata in-kind distribution of Common Stock by Luxco.</footnote>
        <footnote id="F7">These securities are held of record by VAF V. VV V is the sole general partner of VAF V and may be deemed to have voting and investment power over the securities held by VAF V and as a result may be deemed to have beneficial ownership over such securities. VV V disclaims beneficial owners of such shares except to the extent of its pecuniary interest therein.</footnote>
        <footnote id="F8">Represents a change in the form of ownership of VOA by virtue of receipt of shares in the pro-rata in-kind distribution of Common Stock by Luxco.</footnote>
        <footnote id="F9">These securities are held of record by VOA. VV V is the sole general partner of VOA and may be deemed to have voting and investment power over the securities held by VOA and as a result may be deemed to have beneficial ownership over such securities. VV V disclaims beneficial ownership of such shares except to the extent of its pecuniary interests therein.</footnote>
        <footnote id="F10">Represents a change in the form of ownership of VVC CAN by virtue of receipt of shares in the pro-rata in-kind distribution of Common Stock by Luxco.</footnote>
        <footnote id="F11">These securities are held of record by VVC CAN. VV V CAN GP is the sole general partner of &quot;VV V CAN and VV V CAN is the sole general partner of VVC CAN. By virtue of such relationships, VV V CAN GP and VV V CAN may be deemed to have voting and investment power over the securities held by VVC CAN and as a result may be deemed to have beneficial ownership over such securities. VV V CAN disclaims beneficial ownership of the shares held by VVC CAN, except to the extent of its pecuniary interests therein.</footnote>
        <footnote id="F12">Represents a pro-rata in-kind distribution of Common Stock of the Issuer by VVC V without consideration to its partners.</footnote>
        <footnote id="F13">Represents a pro-rata in-kind distribution of Common Stock of the Issuer by VAF V without consideration to its partners.</footnote>
        <footnote id="F14">Represents a pro-rata in-kind distribution of Common Stock of the Issuer by VOA without consideration to its partners.</footnote>
        <footnote id="F15">Represents a pro-rata in-kind distribution of Common Stock of the Issuer by VVC CAN without consideration to its partners.</footnote>
        <footnote id="F16">Represents a change in the form of ownership of VV V by virtue of the receipt of shares in the pro-rata in-kind distribution of Common Stock of the Issuer for no consideration by VVC V, VAF V and VOA.</footnote>
        <footnote id="F17">The shares are held by VV V.</footnote>
        <footnote id="F18">Represents a pro-rata in-kind distribution of Common Stock of the Issuer by VV V without consideration to its members.</footnote>
        <footnote id="F19">Represents a change in the form of ownership of VV V CAN by virtue of the receipt of shares in the pro-rata in-kind distribution of Common Stock of the Issuer for no consideration by VVC CAN.</footnote>
        <footnote id="F20">The shares are held by VV V CAN.</footnote>
        <footnote id="F21">Represents a pro-rata in-kind distribution of Common Stock of the Issuer by VV V CAN without consideration to its partners.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>VERSANT V LUXCO S.A.R.L. By: /s/ Robin L. Praeger, Manager</signatureName>
        <signatureDate>2020-05-20</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>VERSANT VENTURE CAPITAL V, L.P. By:  Versant Ventures V, LLC Its:  General Partner By:  /s/ Robin L. Praeger, Managing Director</signatureName>
        <signatureDate>2020-05-20</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>VERSANT AFFILIATES FUND V, L.P. By:  Versant Ventures V, LLC Its:  General Partner By:  /s/ Robin L. Praeger, Managing Director</signatureName>
        <signatureDate>2020-05-20</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>VERSANT OPHTHALMIC AFFILIATES FUND I, L.P. By:  Versant Ventures V, LLC Its:  General Partner By:  /s/ Robin L. Praeger, Managing Director</signatureName>
        <signatureDate>2020-05-20</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>VERSANT VENTURE CAPITAL V (CANADA) LP By:  Versant Ventures V (Canada), L.P. Its:   General Partner By:  Versant Ventures V GP-GP (Canada), Inc. Its:   General Partner By:  /s/ Robin L. Praeger, Director</signatureName>
        <signatureDate>2020-05-20</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>VERSANT VENTURES V, LLC By:  /s/ Robin L. Praeger, Managing Director</signatureName>
        <signatureDate>2020-05-20</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>VERSANT VENTURES V (CANADA), L.P. By:  Versant Ventures V GP-GP (Canada), Inc. Its:   General Partner By:  /s/ Robin L. Praeger, Director</signatureName>
        <signatureDate>2020-05-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
