FDA Advisory Committee supports approval of Gilead’s once-daily Quad single tablet regimen for HIV

Gilead Sciences, Inc. (Nasdaq: GILD) today announced that the Antiviral Drugs Advisory Committee of the U.S. Food and Drug Administration (FDA) has voted 13 to 1 in support of approval of the Quad, a complete single tablet regimen of elvitegravir, cobicistat, emtricitabine and tenofovir disoproxil fumarate, for the treatment of HIV-1 infection in treatment-naïve adults.

The recommendations of the Advisory Committee are not binding, but will be considered by FDA as the agency completes its review of Gilead’s New Drug Application (NDA) of the Quad. Gilead submitted the NDA on October 27, 2011 and FDA has set a target action date under the Prescription Drug User Fee Act (PDUFA) of August 27, 2012. Applications for marketing approval of the Quad are also pending in Australia, Canada and the European Union.

“With new government guidelines recommending that people diagnosed with HIV begin treatment early, it is important that we continue to simplify and improve HIV therapy,” said Andrew Cheng, MD, PhD, Senior Vice President, HIV Therapeutics and Development Operations, Gilead Sciences. “The Quad is the latest example of Gilead’s ongoing efforts to develop highly effective and well tolerated single tablet regimens for people living with HIV.”

The Quad NDA is supported by the positive results from two pivotal Phase 3 studies in which Quad met its primary objective of non-inferiority as compared to Atripla® (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg) (Study 102) and to a regimen containing ritonavir-boosted atazanavir plus Truvada® (Study 103). The NDA is also supported by Chemistry, Manufacturing and Controls (CMC) information on the individual components of the Quad and the co-formulated single tablet regimen.

In all studies, the Quad was well tolerated and most adverse events were mild to moderate. The most common adverse events observed were nausea, diarrhea, upper respiratory track infection and headache. Overall, there have been nearly 9 million patient years of experience with tenofovir-containing regimens.

About the Quad

The Quad contains four Gilead compounds in a complete once-daily, single tablet regimen: elvitegravir 150 mg; cobicistat 150 mg, a “boosting” agent that enables elvitegravir once-daily dosing; and Truvada (emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg).

Elvitegravir is a member of the integrase inhibitor class of antiretroviral compounds. Unlike other classes, integrase inhibitors interfere with HIV replication by blocking the ability of the virus 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.

Cobicistat is Gilead’s proprietary potent mechanism-based inhibitor of cytochrome P450 3A (CYP3A), an enzyme that metabolizes drugs in the body. Cobicistat acts only as a pharmacoenhancer and has no antiviral activity. In addition to studying the agent as part of the Quad, Gilead is also examining cobicistat’s potential in boosting commercially available HIV protease inhibitors.

The Quad, elvitegravir and cobicistat are investigational products and their safety and efficacy have not yet been established.