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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-07-01</periodOfReport>

    <notSubjectToSection16>true</notSubjectToSection16>

    <issuer>
        <issuerCik>0001613859</issuerCik>
        <issuerName>PRA Health Sciences, Inc.</issuerName>
        <issuerTradingSymbol>PRAH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001472695</rptOwnerCik>
            <rptOwnerName>KKR Group Ltd</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O KOHLBERG KRAVIS ROBERTS &amp; CO. L.P.</rptOwnerStreet1>
            <rptOwnerStreet2>9 WEST 57TH STREET, SUITE 4200</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isTenPercentOwner>true</isTenPercentOwner>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001472696</rptOwnerCik>
            <rptOwnerName>KKR Group Holdings L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O KOHLBERG KRAVIS ROBERTS &amp; CO. L.P.</rptOwnerStreet1>
            <rptOwnerStreet2>9 WEST 57TH STREET, SUITE 4200</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isTenPercentOwner>true</isTenPercentOwner>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-07-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>13195984</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to an internal reorganization in connection with the conversion of KKR &amp; Co. L.P., a Delaware limited partnership, into a Delaware corporation named KKR &amp; Co. Inc., which became effective on July 1, 2018, KKR &amp; Co. L.P. contributed all of its interests in two wholly-owned subsidiaries, KKR Group Holdings L.P. and KKR Group Limited, to a newly formed and wholly-owned subsidiary, KKR Group Holdings Corp., and KKR Group Holdings L.P. and KKR Group Limited were liquidated. KKR Group Holdings L.P. and KKR Group Limited are filing this &quot;exit&quot; Form 4 to report that they are no longer beneficial owners of securities of PRA Health Sciences, Inc. (the &quot;Issuer&quot;).  KKR Group Holdings Corp. is separately filing a Form 3 to report beneficial ownership of securities of the Issuer in connection with the above reorganization. This internal reorganization did not involve any purchase or sale of securities of the Issuer.</footnote>
        <footnote id="F2">Securities are held by KKR PRA Investors L.P. KKR PRA Investors GP II LLC is the sole general partner of KKR PRA Investors L.P. KKR PRA Investors GP LLC is the sole member of KKR PRA Investors GP II LLC. KKR North America Fund XI L.P. is the sole member of KKR PRA Investors GP LLC. KKR Associates North America XI L.P. is the general partner of KKR North America Fund XI L.P. KKR North America XI Limited is the general partner of KKR Associates North America XI L.P. KKR Fund Holdings L.P. is the sole shareholder of KKR North America XI Limited. KKR Fund Holdings GP Limited is a general partner of KKR Fund Holdings L.P.</footnote>
        <footnote id="F3">Prior to the reorganization, KKR Group Holdings L.P. was the general partner of KKR Fund Holdings L.P. and the sole shareholder of KKR Fund Holdings GP Limited and KKR Group Limited was the general partner of KKR Group Holdings L.P.</footnote>
    </footnotes>

    <remarks>Each of the Reporting Persons may have been deemed to be the beneficial owner of all or a portion of the securities reported herein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons engaged in any transactions subject to Section 16 of the Securities Exchange Act of 1934 or are or were the beneficial owners of any securities reported herein, and the Reporting Persons disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.</remarks>

    <ownerSignature>
        <signatureName>KKR GROUP LIMITED By: /s/ Terence Gallagher Name: Terence Gallagher Title: Attorney-in-fact for William J. Janetschek, Director</signatureName>
        <signatureDate>2018-07-02</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>KKR GROUP HOLDINGS L.P. By: KKR Group Limited, its general partner By: /s/ Terence Gallagher Name: Terence Gallagher Title: Attorney-in-fact for William J. Janetschek, Director</signatureName>
        <signatureDate>2018-07-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
