-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001055947-10-000004.txt : 20100204
<SEC-HEADER>0001055947-10-000004.hdr.sgml : 20100204
<ACCEPTANCE-DATETIME>20100204173457
ACCESSION NUMBER:		0001055947-10-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100202
FILED AS OF DATE:		20100204
DATE AS OF CHANGE:		20100204

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LAMPERT MARK N
		CENTRAL INDEX KEY:			0001233840

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34154
		FILM NUMBER:		10575057

	MAIL ADDRESS:	
		STREET 1:		2415 GREEN ST
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94123

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FACET BIOTECH CORP
		CENTRAL INDEX KEY:			0001441848
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				263070657
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1500 SEAPORT BLVD.
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063
		BUSINESS PHONE:		650-454-1000

	MAIL ADDRESS:	
		STREET 1:		1500 SEAPORT BLVD.
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Biotech Spinco, Inc.
		DATE OF NAME CHANGE:	20080804

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BIOTECHNOLOGY VALUE FUND L P
		CENTRAL INDEX KEY:			0000918923
		STANDARD INDUSTRIAL CLASSIFICATION:	INVESTMENT ADVICE [6282]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34154
		FILM NUMBER:		10575060

	BUSINESS ADDRESS:	
		STREET 1:		900 N. MICHIGAN AVENUE, SUITE 1100
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611
		BUSINESS PHONE:		3125066500

	MAIL ADDRESS:	
		STREET 1:		900 N. MICHIGAN AVENUE, SUITE 1100
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BVF PARTNERS L P/IL
		CENTRAL INDEX KEY:			0001055947

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34154
		FILM NUMBER:		10575061

	BUSINESS ADDRESS:	
		STREET 1:		ONE SANSOME ST
		STREET 2:		39TH FL
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94104
		BUSINESS PHONE:		3125066500

	MAIL ADDRESS:	
		STREET 1:		900 N. MICHIGAN AVENUE
		STREET 2:		SUITE 1100
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BVF INC/IL
		CENTRAL INDEX KEY:			0001056807
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34154
		FILM NUMBER:		10575056

	BUSINESS ADDRESS:	
		STREET 1:		ONE SANSOME ST
		STREET 2:		39TH FLOOR
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94104
		BUSINESS PHONE:		3125066500

	MAIL ADDRESS:	
		STREET 1:		C/O GROSVENOR CAPITAL MANAGEMENT
		STREET 2:		900 N. MICHIGAN AVENUE, SUITE 1100
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BIOTECHNOLOGY VALUE FUND II LP
		CENTRAL INDEX KEY:			0001102444
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34154
		FILM NUMBER:		10575059

	BUSINESS ADDRESS:	
		STREET 1:		ONE SANSOME ST
		STREET 2:		39TH FL.
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94104
		BUSINESS PHONE:		3125066500

	MAIL ADDRESS:	
		STREET 1:		C/O GROSVENOR CAPITAL MANAGEMENT
		STREET 2:		900 N. MICHIGAN AVENUE, SUITE 1100
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BVF INVESTMENTS LLC
		CENTRAL INDEX KEY:			0001132245
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34154
		FILM NUMBER:		10575058

	BUSINESS ADDRESS:	
		STREET 1:		ONE SANSOME ST. 39TH FL
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94104
		BUSINESS PHONE:		3125066500

	MAIL ADDRESS:	
		STREET 1:		C/O GROSVENOR CAPITAL MANAGEMENT LP
		STREET 2:		900 N. MICHIGAN AVENUE, SUITE 1100
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611
</SEC-HEADER>
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<SEQUENCE>1
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<DESCRIPTION>PRIMARY DOCUMENT
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    <documentType>4</documentType>

    <periodOfReport>2010-02-02</periodOfReport>

    <issuer>
        <issuerCik>0001441848</issuerCik>
        <issuerName>FACET BIOTECH CORP</issuerName>
        <issuerTradingSymbol>FACT</issuerTradingSymbol>
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    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001055947</rptOwnerCik>
            <rptOwnerName>BVF PARTNERS L P/IL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>900 N. MICHIGAN AVE., SUITE 1100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
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        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000918923</rptOwnerCik>
            <rptOwnerName>BIOTECHNOLOGY VALUE FUND L P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>900 N. MICHIGAN AVE., SUITE 1100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Direct Beneficial Owner</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001102444</rptOwnerCik>
            <rptOwnerName>BIOTECHNOLOGY VALUE FUND II LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>900 N. MICHIGAN AVE., SUITE 1100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Direct Beneficial Owner</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001132245</rptOwnerCik>
            <rptOwnerName>BVF INVESTMENTS LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>900 N. MICHIGAN AVE., SUITE 1100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Direct Beneficial Owner</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001233840</rptOwnerCik>
            <rptOwnerName>LAMPERT MARK N</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>900 N. MICHIGAN AVE., SUITE 1100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001056807</rptOwnerCik>
            <rptOwnerName>BVF INC/IL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>900 N. MICHIGAN AVE., SUITE 1100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</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>2010-02-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.80</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3749121</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
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                    <footnoteId id="F1"/>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
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                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
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        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>12000</value>
                    <footnoteId id="F1"/>
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                <transactionPricePerShare>
                    <value>15.80</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
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                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2010-02-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>3138</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.80</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.80</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3770259</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>7000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.80</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3777259</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F4"/>
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                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>29611</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.6318</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3806870</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
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                    <value></value>
                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>21000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.6318</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3827870</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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                    <value></value>
                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>73000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.6318</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3900870</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3900870</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F5"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>General partner and manager of entities with direct ownership.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3900870</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>General Partner of entity with indirect ownership.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3900870</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F7"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Sole shareholder and sole director of entity with indirect ownership.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Units may represent aggregation of daily trade activity.  Details regarding individual execution amounts and prices are available upon request.</footnote>
        <footnote id="F2">Shares directly beneficially owned by Biotechnology Value Fund, L.P. (&quot;BVF&quot;)</footnote>
        <footnote id="F3">Shares directly beneficially owned by Biotechnology Value Fund II, L.P. (&quot;BVF II&quot;)</footnote>
        <footnote id="F4">The shares of Common Stock are directly beneficially owned by BVF Investments, LLC (&quot;BVFLLC&quot;), a Delaware limited liability company.  Pursuant to the operating agreement of BVFLLC, BVF Partners, L.P., a Delaware limited partnership (&quot;Partners&quot;) is authorized, among other things, to invest the contributed capital of Samana Capital, L.P., the majority member of BVFLLC, in the shares of Common Stock and other securities and to vote, exercise or convert and dispose of such securities and is entitled to receive fees based on assets under management and, subject to certain exceptions, allocations  based on realized and unrealized gains on such assets.</footnote>
        <footnote id="F5">The shares of Common Stock are indirectly beneficially owned by Partners.  Partners is the general partner of BVF and BVF II and is the manager of BVFLLC.</footnote>
        <footnote id="F6">The shares of Common Stock are indirectly beneficially owned by BVF Inc., a Delaware corporation (&quot;BVF Inc.&quot;).  BVF Inc. is the general partner of Partners.</footnote>
        <footnote id="F7">Mark N. Lampert is the sole shareholder, sole director, and an officer of BVF Inc.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>BVF Partners L.P., By: BVF Inc., its GP, By: /s/ Mark N. Lampert</signatureName>
        <signatureDate>2010-02-04</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BIOTECHNOLOGY VALUE FUND, L.P. By: BVF Partners L.P., its GP, By: BVF Inc., By: /s/ Mark N. Lampert</signatureName>
        <signatureDate>2010-02-04</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BIOTECHNOLOGY VALUE FUND II, L.P., By: BVF Partners L.P., its GP, By: BVF Inc., By: /s/ Mark N. Lampert</signatureName>
        <signatureDate>2010-02-04</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BVF INVESTMENTS, L.L.C., By: BVF Partners L.P., its Manager, By: BVF Inc., By: /s/ Mark N. Lampert</signatureName>
        <signatureDate>2010-02-04</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BVF INC., By: /s/ Mark N. Lampert</signatureName>
        <signatureDate>2010-02-04</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>MARK N. LAMPERT By: /s/ Mark N. Lampert</signatureName>
        <signatureDate>2010-02-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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