European CHMP Adopts Positive Opinion for Stribild®, a Once-Daily, Integrase Inhibitor-Based, Single Tablet Regimen for the Treatment of HIV-1 Infection

Gilead Sciences, Inc.Patrick O’Brien, 650-522-1936 (Investors)Stephen Head, +44 (208) 587-2359 (Media, Europe)Erin Rau, 650-522-5635 (Media, U.S.)

Gilead Sciences, Inc. (Nasdaq: GILD) today announced that the Committee for Medicinal Products for Human Use (CHMP), the scientific committee of the European Medicines Agency (EMA), has adopted a positive opinion on the company’s Marketing Authorisation Application (MAA) for the once-daily, single tablet regimen Stribild for the treatment of HIV-1 infection in adult patients who are antiretroviral-naïve or are infected with HIV-1 without known mutations associated with resistance to any of the three antiretroviral agents in Stribild. Stribild combines elvitegravir, an integrase inhibitor, and cobicistat, a pharmacoenhancing agent, with Truvada (emtricitabine and tenofovir disoproxil (as fumarate)). The CHMP’s positive recommendation will be reviewed by the European Commission, which has the authority to approve medicines for use in the 27 countries of the European Union (EU).

“With its potency, tolerability and convenient once-daily dosing, we believe Stribild has the potential to be an important treatment option for patients new to therapy or with no known resistance to any of the three components of the product,” said John C. Martin, PhD, Chairman and Chief Executive Officer, Gilead Sciences. “We are pleased with today’s positive opinion from the CHMP, and anticipate receiving a final decision from the European Commission on our application for Stribild in the coming months.”

The regulatory filing for Stribild is supported by 48-week data from two Phase 3 double-blind, active-controlled, randomized studies in which Stribild met its primary objective of non-inferiority compared to Atripla (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil (as fumarate) 300 mg) (Study 102) and to a regimen containing ritonavir-boosted atazanavir plus Truvada (Study 103). In November 2012, data from Studies 102 and 103 were presented at the 11th International Congress on Drug Therapy in HIV Infection in Glasgow, United Kingdom. These data demonstrated that Stribild maintained high antiviral efficacy through 96 weeks of treatment. In all studies, Stribild was well tolerated and most adverse events were mild to moderate. The most common adverse events observed were nausea, diarrhea, upper respiratory tract infection and headache.

Stribild has received marketing approval in the United States, Canada, South Korea and Australia. To increase access to Stribild in the developing world, Gilead has granted its Indian manufacturing partners and the Medicines Patent Pool the right to develop and distribute generic versions of Stribild in 100 developing countries. These agreements include a complete technology transfer from Gilead of the manufacturing process for the single tablet regimen.

Stribild contains four Gilead compounds in a complete once-daily, single tablet regimen: elvitegravir 150 mg; cobicistat 150 mg; emtricitabine 200 mg; and tenofovir disoproxil (as fumarate) 300 mg.

Elvitegravir is a member of the integrase inhibitor class of antiretroviral compounds. Integrase inhibitors block the ability of HIV to integrate into the genetic material of human cells. Elvitegravir was licensed by Gilead from Japan Tobacco Inc. (JT) in March 2005. Under the terms of Gilead’s agreement with JT, Gilead has exclusive rights to develop and commercialize elvitegravir in all countries of the world, excluding Japan, where JT retains rights. Gilead submitted a New Drug Application (NDA) to U.S. Food and Drug Administration (FDA) for elvitegravir as a standalone agent on June 27, 2012, and the agency has set a target action date under the Prescription Drug User Fee Act (PDUFA) of April 27, 2013. A Marketing Authorisation Application (MAA) for elvitegravir in the EU was validated for review by the EMA on June 18, 2012.

Cobicistat is Gilead’s proprietary potent mechanism-based inhibitor of cytochrome P450 3A (CYP3A), an enzyme that metabolizes drugs in the body. Unlike ritonavir, cobicistat acts only as a pharmacoenhancing or “boosting” agent and has no antiviral activity. Gilead submitted an NDA to FDA for cobicistat as a standalone agent on June 28, 2012, and a PDUFA date of April 28, 2013 has been set. An MAA for cobicistat in the EU was validated for review by EMA on May 22, 2012.

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 Asia Pacific.

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. These risks include the uncertainty related to the timing of the European Commission’s decision and whether the European Commission will approve Stribild. In addition, any marketing approval provided by the European Commission or other regulatory authorities, if granted, may have significant limitations on its use. Further, the U.S. Food and Drug Administration and European Commission may not approve pending marketing applications for elvitegravir or cobicistat as standalone agents. 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 Annual Report on Form 10-K for the year ended December 31, 2012, 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.