Gilead Sciences Receives Refuse to File Notification From U.S. FDA on New Drug Application for Single-Tablet Regimen of Truvada(R) and TMC278

- Additional CMC Information Required Before Resubmission of New Drug Application -

FOSTER CITY, Calif., Jan 25, 2011 (BUSINESS WIRE) -- Gilead Sciences, Inc. (Nasdaq:GILD) announced today that it has received a "refuse to file" notification from the U.S. Food and Drug Administration (FDA) regarding Gilead's New Drug Application (NDA) for the single-tablet regimen of Truvada(R) (emtricitabine and tenofovir disoproxil fumarate) and Tibotec Pharmaceuticals' investigational non-nucleoside reverse transcriptase inhibitor TMC278 (rilpivirine hydrochloride) for HIV-1 infection in adults. In its communication, the FDA requested additional information with respect to the Chemistry, Manufacturing and Controls (CMC) section of the Truvada/TMC278 NDA submission. The letter stated that the application does not contain sufficient information on the analytical methodology to establish acceptable levels of recently identified degradants related to emtricitabine.

"We are working to validate the methodology to resolve this issue and provide the required information to the FDA," said Norbert Bischofberger, PhD, Executive Vice President, Research and Development and Chief Scientific Officer, Gilead Sciences. "We expect to be in a position to resubmit the Truvada/TMC278 NDA with the additional requested information prior to the end of the first quarter of this year."

The FDA has the ability to formally file or refuse to file an application within 60 days of the completion of the submission, which occurred on November 23, 2010.

About Gilead

Gilead Sciences is a biopharmaceutical company that discovers, develops and commercializes innovative therapeutics in areas of unmet medical need. The company's mission is to advance the care of patients suffering from life-threatening diseases worldwide. Headquartered in Foster City, California, Gilead has operations in North America, Europe and Australia.

Forward-Looking Statement

This press release includes forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995, that are subject to risks, uncertainties and other factors, including risks related to Gilead's ability to resubmit the NDA in the timeline currently anticipated. In addition, the FDA may not be satisfied with the additional informational submitted by Gilead and may not approve Truvada/TMC278 for the treatment of HIV-1 infection in adults. Further, any marketing approval, if granted, may have significant limitations on its use. Further, Gilead and Tibotec may make a strategic decision to discontinue development of the Truvada/TMC278 if, for example, the market for the product fails to materialize as expected. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. The reader is cautioned not to rely on these forward-looking statements. These and other risks are described in detail in Gilead's Quarterly Report on Form 10-Q for the quarter ended September 30, 2010, as filed with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation to update any such forward-looking statements.

For more information on Gilead Sciences, please visit www.gilead.com or call the Gilead Public Affairs Department at 1-800-GILEAD-5 (1-800-445-3235).

SOURCE: Gilead Sciences, Inc.

Gilead Sciences, Inc.
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