FIRST AMENDMENT TO LOAN AND SECURITYAGREEMENT

Exhibit 10.30

Execution Copy

FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT

THIS FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT (the “First Amendment”) is made this 5^th day of December, 2002, by and between Exelixis, Inc., a Delaware corporation (“Exelixis”), and SmithKlineBeecham Corporation, a Pennsylvania corporation, doing business as GlaxoSmithKline (“GSK”). Exelixis and GSK are each referred to herein by name or as a “Party” or, collectively, as “Parties”.

WHEREAS, Exelixis and GSK are parties to that certain Loan and Security Agreement dated October 28, 2002 (as the same may be amended, supplemented, restated or otherwise modified from time to time, the “Loan Agreement”)(all capitalized terms used, but not specifically defined, herein shall have the meaning provided for such terms in the Loan Agreement); and

WHEREAS, Exelixis has requested that GSK allow Exelixis to use deposit account #3300366867 as a “pass through” account for securities account #888-02658 and to deem both accounts as the Deposit Account referred to and defined in the Loan Agreement and has entered into a certain Control Agreement dated November 13, 2002, by and among Exelixis, GSK and SVB Securities, and has further agreed to enter into an a control agreement for deposit account #3300366867 and securities account #886-02658 and to deem both control agreements as the Securities Account Control Agreement referred to in the Loan Agreement; and

NOW, THEREFORE, in consideration of the foregoing and of other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, GSK and Exelixis agree as follows:

This Amendment shall not constitute a waiver or modification of any of GSK’s rights and remedies or of any of the terms, conditions, warranties, representations, or covenants contained in the Loan Agreement, except as specifically set forth above, and GSK hereby reserves all of its rights and remedies pursuant to the Loan Agreement and applicable law.

This Amendment may be executed in counterparts, each of which, when taken together, shall be deemed to be one and the same instrument.

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IN WITNESS WHEREOF, the parties have executed this First Amendment to Loan and Security Agreement as a sealed instrument as of the date written above.

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EXECUTION COPY

Schedule 3.1.3

DEPOSIT ACCOUNT

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