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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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 n4BuRaXNk11o5Ye69ZWicQ==

<SEC-DOCUMENT>0000882796-06-000061.txt : 20060815
<SEC-HEADER>0000882796-06-000061.hdr.sgml : 20060815
<ACCEPTANCE-DATETIME>20060815140905
ACCESSION NUMBER:		0000882796-06-000061
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060814
FILED AS OF DATE:		20060815
DATE AS OF CHANGE:		20060815

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BIOCRYST PHARMACEUTICALS INC
		CENTRAL INDEX KEY:			0000882796
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				621413174
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1220

	BUSINESS ADDRESS:	
		STREET 1:		2190 PARKWAY LAKE DR
		CITY:			BIRMINGHAM
		STATE:			AL
		ZIP:			35244
		BUSINESS PHONE:		2054444600

	MAIL ADDRESS:	
		STREET 1:		2190 PARKWAY LAKE DR
		CITY:			BIRMINGHAM
		STATE:			AL
		ZIP:			35244

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ALEXANDER W JAMES
		CENTRAL INDEX KEY:			0001257151

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23186
		FILM NUMBER:		061034462

	MAIL ADDRESS:	
		STREET 1:		307 WHIPERWOOD DRIVE
		CITY:			CARY
		STATE:			NC
		ZIP:			27511
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-08-14</periodOfReport>

    <issuer>
        <issuerCik>0000882796</issuerCik>
        <issuerName>BIOCRYST PHARMACEUTICALS INC</issuerName>
        <issuerTradingSymbol>BCRX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001257151</rptOwnerCik>
            <rptOwnerName>ALEXANDER W JAMES</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2190 PARKWAY LAKE DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BIRMINGHAM</rptOwnerCity>
            <rptOwnerState>AL</rptOwnerState>
            <rptOwnerZipCode>35244-</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SR. VP, Chief Medical Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-08-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1285</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1285</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Michael Richardson by Power of Attorney</signatureName>
        <signatureDate>2006-08-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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