<SEC-DOCUMENT>0001193125-25-297204.txt : 20251125
<SEC-HEADER>0001193125-25-297204.hdr.sgml : 20251125
<ACCEPTANCE-DATETIME>20251125161006
ACCESSION NUMBER:		0001193125-25-297204
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251121
FILED AS OF DATE:		20251125
DATE AS OF CHANGE:		20251125

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Frankenfield Christopher James
		CENTRAL INDEX KEY:			0001988344
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-40925
		FILM NUMBER:		251521176

	MAIL ADDRESS:	
		STREET 1:		C/O XILIO THERAPEUTICS, INC.
		STREET 2:		828 WINTER STREET
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Xilio Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001840233
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				851623397
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		828 WINTER STREET
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		617-833-1027

	MAIL ADDRESS:	
		STREET 1:		828 WINTER STREET
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>ownership.xml
<DESCRIPTION>4
<TEXT>
<XML>
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    <schemaVersion>X0508</schemaVersion>

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    <periodOfReport>2025-11-21</periodOfReport>

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        <issuerName>Xilio Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>XLO</issuerTradingSymbol>
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            <rptOwnerName>Frankenfield Christopher James</rptOwnerName>
        </reportingOwnerId>
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            <rptOwnerStreet2>SUITE 300</rptOwnerStreet2>
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            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02451</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
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                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.50</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-11-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>150000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F4"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F8"/>
            </exerciseDate>
            <expirationDate>
                <value>2033-08-02</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>150000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>150000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.785</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-11-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>300000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F4"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2033-08-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>300000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.50</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-11-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>300000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F4"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2033-08-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>300000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>300000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On October 8, 2025, the Board of Directors (the &quot;Board&quot;) approved the adoption of the Xilio Therapeutics, Inc. 2025 Stock Incentive Plan (the &quot;2025 Plan&quot;), subject to stockholder approval of the adoption of the 2025 Plan. On October 8, 2025, the Compensation Committee of the Board granted these options (referred to as &quot;Tranche 1 Options&quot; in the 2025 Plan) to the Reporting Person, subject to stockholder approval of the adoption of the 2025 Plan. The stockholders approved the adoption of the 2025 Plan on November 21, 2025.</footnote>
        <footnote id="F2">The options vest in 36 equal monthly installments over the three-year period beginning on December 21, 2025, subject to the Reporting Person's continued service to the registrant through each applicable vesting date.</footnote>
        <footnote id="F3">Immediately exercisable.</footnote>
        <footnote id="F4">The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the &quot;Option Repricing&quot;). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.</footnote>
        <footnote id="F5">This option was granted on February 22, 2022. The shares underlying the option began vesting on March 1, 2022 and continue to vest in equal monthly installments thereafter through February 1, 2026.</footnote>
        <footnote id="F6">This option was granted on September 1, 2022. The shares underlying the option began vesting on September 1, 2022 and continue to vest in equal monthly installments thereafter through August 1, 2026.</footnote>
        <footnote id="F7">This option was granted on January 1, 2023. The shares underlying the option began vesting on February 1, 2023 and continue to vest in equal monthly installments thereafter through January 1, 2027.</footnote>
        <footnote id="F8">This option was granted on August 3, 2023. The shares underlying the option began vesting on September 1, 2023 and continue to vest in equal monthly installments thereafter through August 1, 2027.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Kevin Brennan, Attorney-in-Fact</signatureName>
        <signatureDate>2025-11-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
