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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 fBmSC9c7tGoRY7/SK/JvLw==

<SEC-DOCUMENT>0001140361-10-023059.txt : 20100525
<SEC-HEADER>0001140361-10-023059.hdr.sgml : 20100525
<ACCEPTANCE-DATETIME>20100525170043
ACCESSION NUMBER:		0001140361-10-023059
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100521
FILED AS OF DATE:		20100525
DATE AS OF CHANGE:		20100525

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Spiegel Robert J.
		CENTRAL INDEX KEY:			0001492256

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33560
		FILM NUMBER:		10857568

	MAIL ADDRESS:	
		STREET 1:		C/O GERON CORPORATION
		STREET 2:		230 CONSTITUTION DRIVE
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Capstone Therapeutics Corp.
		CENTRAL INDEX KEY:			0000887151
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				860585310
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1275 WEST WASHINGTON STREET
		STREET 2:		SUITE 101
		CITY:			TEMPE
		STATE:			AZ
		ZIP:			85281
		BUSINESS PHONE:		6022865520

	MAIL ADDRESS:	
		STREET 1:		1275 WEST WASHINGTON STREET
		STREET 2:		SUITE 101
		CITY:			TEMPE
		STATE:			AZ
		ZIP:			85281

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ORTHOLOGIC CORP
		DATE OF NAME CHANGE:	19940211
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-05-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000887151</issuerCik>
        <issuerName>Capstone Therapeutics Corp.</issuerName>
        <issuerTradingSymbol>CAPS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001492256</rptOwnerCik>
            <rptOwnerName>Spiegel Robert J.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1275 WEST WASHINGTON STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 101</rptOwnerStreet2>
            <rptOwnerCity>TEMPE</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85281</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>.82</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-05-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2010-05-21</value>
            </exerciseDate>
            <expirationDate>
                <value>2020-05-21</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>50000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Les M. Taeger, Attorney in-fact</signatureName>
        <signatureDate>2010-05-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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