FDA Approves New Once-a-Day HIV Pill

MONDAY, Aug. 27 (HealthDay News) -- A new pill to treat HIV infection that combines four medicines and only has to be taken once a day was approved by the U.S. Food and Drug Administration on Monday.

Stribild, which will be marketed by maker Gilead Sciences, contains the HIV drugs elvitegravir, cobicistat, emtricitabine and tenofovir disoproxil fumarate. It will be prescribed to people who have never been treated for HIV infection, the agency said in a statement.

Two of the drugs, elvitegravir and cobicistat, are new, the FDA noted. Elvitegravir interferes with one of the enzymes that HIV needs to multiply, while cobicistat inhibits an enzyme that metabolizes certain HIV drugs and so prolongs the effect of elvitegravir. The combination of emtricitabine and tenofovir disoproxil fumarate is already marketed as Truvada, and they work in concert to block another enzyme that HIV needs to replicate.

"Through continued research and drug development, treatment for those infected with HIV has evolved from multi-pill regimens to single-pill regimens," Dr. Edward Cox, director of the Office of Antimicrobial Products in FDA's Center for Drug Evaluation and Research, said in the agency statement. "New combination HIV drugs like Stribild help simplify treatment regimens."

Earlier this year, the agency approved the first over-the-counter rapid HIV test for home use and gave its blessing to the first drug to be used to prevent HIV infection when used together with safe sex practices.

Two clinical trials found between 88 percent and 90 percent of patients treated with Stribild had an undetectable amount of HIV in their blood after 48 weeks of treatment, the FDA said.

The drug will carry a boxed warning that says it can cause a build-up of lactic acid in the blood and severe liver problems, both of which can be fatal. In the clinical trials, common side effects included nausea and diarrhea. Serious side effects include new or worsening kidney problems, decreased bone mineral density, fat redistribution and changes in the immune system, the FDA said.

Gilead, which is based in Foster City, Calif., must conduct more research to further determine the drug's safety in women and children, how resistance develops to Stribild and possible interactions with other drugs, the FDA said.