Bristol-Myers Squibb and Gilead Sciences have signed a licensing agreement for Bristol-Myers Squibb to develop and commercialize a fixed-dose combination containing Bristol-Myers Squibb's protease inhibitor REYATAZ (atazanavir sulfate) and Gilead's cobicistat, a pharmacoenhancing or "boosting" agent that increases blood levels of certain HIV medicines to potentially allow for one pill once daily dosing. Gilead is currently studying atazanavir and cobicistat in phase II and III studies in HIV-1 treatment-naive patients.

REYATAZ is a prescription medicine used in combination with other medicines to treat people 6 years of age and older who are infected with HIV. REYATAZ should not be taken if patients are allergic to REYATAZ or to any of its ingredients.

Cobicistat is Gilead's proprietary potent mechanism-based inhibitor of cytochrome P450 3A (CYP3A), an enzyme that metabolizes drugs in the body. Cobicistat is an investigational product and has not yet been determined to be safe or efficacious in humans.

Bristol-Myers Squibb will be responsible for the formulation, manufacturing, development, registration, distribution, and commercialization of the REYATAZ and cobicistat fixed-dose combination worldwide. Under the terms of the agreement, Bristol-Myers Squibb will pay Gilead an undisclosed royalty based on annual net sales of the product. Gilead retains sole rights for the manufacture, development and commercialization of cobicistat as a stand-alone product and for use in combination with other agents.