-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Ju+EbQ+QmmPbKPLtSzOjhtdfiIpsTY6l7pt/cRLAjdhV15HSFB6C35XM5jcSf87T
 A546VRZJ/EVNK2bVyN9TRg==

<SEC-DOCUMENT>0001209191-09-011695.txt : 20090226
<SEC-HEADER>0001209191-09-011695.hdr.sgml : 20090226
<ACCEPTANCE-DATETIME>20090226085541
ACCESSION NUMBER:		0001209191-09-011695
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090224
FILED AS OF DATE:		20090226
DATE AS OF CHANGE:		20090226

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LA JOLLA PHARMACEUTICAL CO
		CENTRAL INDEX KEY:			0000920465
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				330361285
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6455 NANCY RIDGE DR
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121
		BUSINESS PHONE:		8584526600

	MAIL ADDRESS:	
		STREET 1:		6455 NANCY RIDGE DR
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Frazier Healthcare V, LP
		CENTRAL INDEX KEY:			0001341169
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24274
		FILM NUMBER:		09635717

	BUSINESS ADDRESS:	
		STREET 1:		601 UNION STREET, SUITE 3200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98101
		BUSINESS PHONE:		(206) 621-7200

	MAIL ADDRESS:	
		STREET 1:		601 UNION STREET, SUITE 3200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98101

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FHM V, LLC
		CENTRAL INDEX KEY:			0001346944

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24274
		FILM NUMBER:		09635716

	BUSINESS ADDRESS:	
		STREET 1:		601 UNION STREET, SUITE 3200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98101
		BUSINESS PHONE:		(206) 621-7200

	MAIL ADDRESS:	
		STREET 1:		601 UNION STREET, SUITE 3200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98101

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FHM V, LP
		CENTRAL INDEX KEY:			0001346948

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24274
		FILM NUMBER:		09635715

	BUSINESS ADDRESS:	
		STREET 1:		601 UNION STREET, SUITE 3200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98101
		BUSINESS PHONE:		(206) 621-7200

	MAIL ADDRESS:	
		STREET 1:		601 UNION STREET, SUITE 3200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98101
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-02-24</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0000920465</issuerCik>
        <issuerName>LA JOLLA PHARMACEUTICAL CO</issuerName>
        <issuerTradingSymbol>LJPC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001341169</rptOwnerCik>
            <rptOwnerName>Frazier Healthcare V, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>601 UNION STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3200</rptOwnerStreet2>
            <rptOwnerCity>SEATTLE</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98101</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001346944</rptOwnerCik>
            <rptOwnerName>FHM V, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>601 UNION STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3200</rptOwnerStreet2>
            <rptOwnerCity>SEATTLE</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98101</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001346948</rptOwnerCik>
            <rptOwnerName>FHM V, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>601 UNION STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3200</rptOwnerStreet2>
            <rptOwnerCity>SEATTLE</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98101</rptOwnerZipCode>
            <rptOwnerStateDescription></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>2009-02-24</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1662000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.0727</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5470555</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">This is the weight average sale price for all sales reported on this filing.  The range of prices was $0.10-$0.065.  Upon request the reporting person will provide to the SEC staff, the issuer or any security holder of the issuer, upon request, full information regarding the number of shares purchased or sold at each separate price.</footnote>
        <footnote id="F2">These securities are owned directly by Frazier Healthcare V, LP, the designated filer.  FHM V, LP, a joint filer, serves as the general partner of Frazier Healthcare V, LP and FHM V, LLC, serves as the general partner of FHM V, LP.  FHM V, LP and FHM V, LLC disclaim beneficial ownership of the reported securities except to the extent of their pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Frazier Healthcare V, LP, By FHM V, LP, its general partner, By FHM V, LLC, its general partner By /s/ Thomas S. Hodge, Chief Operating Officer</signatureName>
        <signatureDate>2009-02-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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