<SEC-DOCUMENT>0001387131-23-003381.txt : 20230313
<SEC-HEADER>0001387131-23-003381.hdr.sgml : 20230313
<ACCEPTANCE-DATETIME>20230313182725
ACCESSION NUMBER:		0001387131-23-003381
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230308
FILED AS OF DATE:		20230313
DATE AS OF CHANGE:		20230313

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Zanganeh Mahkam
		CENTRAL INDEX KEY:			0001507650

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-36866
		FILM NUMBER:		23728626

	MAIL ADDRESS:	
		STREET 1:		51 ADAM WAY
		CITY:			ATHERTON
		STATE:			CA
		ZIP:			94027

	FORMER NAME:	
		FORMER CONFORMED NAME:	Zanganeh Maky
		DATE OF NAME CHANGE:	20101210

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Summit Therapeutics Inc.
		CENTRAL INDEX KEY:			0001599298
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2882 SAND HILL ROAD
		STREET 2:		SUITE 106
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025
		BUSINESS PHONE:		617-514-7149

	MAIL ADDRESS:	
		STREET 1:		2882 SAND HILL ROAD
		STREET 2:		SUITE 106
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Summit Therapeutics plc
		DATE OF NAME CHANGE:	20150219

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Summit Corp plc
		DATE OF NAME CHANGE:	20140205
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>zangeneh-form4a_030823.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2023-03-08</periodOfReport>

    <dateOfOriginalSubmission>2023-03-08</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001599298</issuerCik>
        <issuerName>Summit Therapeutics Inc.</issuerName>
        <issuerTradingSymbol>SMMT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001507650</rptOwnerCik>
            <rptOwnerName>Zanganeh Mahkam</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SUMMIT THERAPEUTICS INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2882 SAND HILL ROAD, SUITE 106</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Co-CEO &amp; President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-03-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>16778415</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.05</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24573798</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By the Mahkam Zanganeh Revocable Trust, with the Reporting Person as Trustee.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-03-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>6748629</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.05</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9884095</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By the Shaun Zanganeh Irrevocable Trust, with the Reporting Person as Trustee.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents the number of shares of Common Stock that the Reporting Person purchased in the Issuer's rights offering.</footnote>
        <footnote id="F2">Includes the number of shares of Common Stock that were inadvertently previously disclosed as being held by Dr. Zanganeh personally, which are held by the Mahkam Zanganeh Revocable Trust. Dr. Zanganeh does not directly hold any shares personally, all of her shares are held through the Mahkam Zanganeh Revocable Trust.</footnote>
        <footnote id="F3">The Reporting Person disclaims beneficial ownership of these securities except to the extent of her pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Mahkam Zanganeh</signatureName>
        <signatureDate>2023-03-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
