FDA Grants Priority Review for Cabozantinib in Medullary Thyroid Cancer

FDA Grants Priority Review for Cabozantinib in Medullary Thyroid Cancer

<0> Exelixis, Inc.Charles Butler, 650-837-7277Vice President, Investor Relations and Corporate Communications </0>

Exelixis, Inc. (NASDAQ:EXEL) today announced that the U.S. Food and Drug Administration (FDA) has accepted for filing the New Drug Application (NDA) for cabozantinib as a treatment for patients with progressive, unresectable, locally advanced, or metastatic medullary thyroid cancer (MTC). The FDA also granted priority review designation to the NDA for cabozantinib.

The Prescription Drug User Fee Act (PDUFA) action date is November 29, 2012. Priority Review is granted to a pharmaceutical product that, if approved, would meet an unmet medical need for a serious and life-threatening condition.

Cabozantinib is a potent inhibitor of MET, VEGFR2 and RET. RET is a receptor tyrosine kinase that is frequently activated by point mutation in medullary thyroid carcinomas. The therapeutic role of cabozantinib is currently being investigated across several tumor types. MET is upregulated in many tumor types, thus facilitating tumor cell escape by promoting the formation of more aggressive phenotypes, resulting in metastasis. MET-driven metastasis may be further stimulated by hypoxic conditions in the tumor environment, which are often exacerbated by selective VEGF-pathway inhibitors. In preclinical studies, cabozantinib has shown powerful tumoricidal, antimetastatic and antiangiogenic effects, including:

Exelixis, Inc. is a biotechnology company committed to developing small molecule therapies for the treatment of cancer. Exelixis is focusing its proprietary resources and development efforts exclusively on cabozantinib (XL184), its most advanced product candidate, in order to maximize the therapeutic and commercial potential of this compound. Exelixis believes cabozantinib has the potential to be a high-quality, broadly-active, differentiated pharmaceutical product that can make a meaningful difference in the lives of patients. Exelixis has also established a portfolio of other novel compounds that it believes have the potential to address serious unmet medical needs, many of which are being advanced by partners as part of collaborations. For more information, please visit the company's web site at .

This press release contains forward-looking statements, including, without limitation, statements related to: the continued development and clinical, therapeutic and commercial potential of, and opportunities for, cabozantinib; and potential future regulatory approval of cabozantinib and the timing thereof. Words such as “would,” “believes,” “potential,” and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon Exelixis' current plans, assumptions, beliefs and expectations. Forward-looking statements involve risks and uncertainties. Exelixis' actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties, which include, without limitation: risks related to the potential failure of cabozantinib to demonstrate safety and efficacy in clinical testing; Exelixis’ ability to conduct clinical trials of cabozantinib sufficient to achieve a positive completion; the sufficiency of Exelixis’ capital and other resources; the uncertain timing and level of expenses associated with the development of cabozantinib; the uncertainty of the FDA approval process; timely receipt of potential reimbursements, milestones, royalties and profits under Exelixis’ collaborative agreements; Exelixis’ ability to enter into new collaborations; market competition; and changes in economic and business conditions. These and other risk factors are discussed under “Risk Factors” and elsewhere in Exelixis’ quarterly report on Form 10-Q for the quarter ended March 30, 2012, filed with the Securities and Exchange Commission on May 3, 2012, and Exelixis’ other filings with the SEC. Exelixis expressly disclaims any duty, obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in Exelixis’ expectations with regard thereto or any change in events, conditions or circumstances on which any such statements are based.