TUESDAY, Aug. 28 (HealthDay News) -- Stribild (elvitegravir, cobicistat, emtricitabine, tenofovir disoproxil fumarate) has been approved by the U.S. Food and Drug Administration to treat adults with HIV.

The combination drug, which only has to be taken once a day, interferes with enzymes that are needed for the virus to multiply, the FDA said in a news release.

The safety and effectiveness of Stribild were evaluated in clinical studies involving 1,408 adults. Of those treated with the new drug, between 88 and 90 percent had undetectable levels of HIV in their blood, compared with roughly 84 percent who had undetectable levels among those treated with other anti-HIV drugs, the agency said.

As with similar HIV medications, Stribild's label will include a boxed warning of the potential for a lethal build-up of lactic acid in the blood or severe liver problems, the FDA said.

The most common side effects reported during clinical testing included nausea and diarrhea. More serious but less common adverse reactions included new or worsening kidney problems, a drop in bone mineral density, and immune system changes.

Foster City, Calif.-based drug maker Gilead Sciences will have to conduct additional studies of the drug's safety in women and children, how the drug may become resistant to the AIDS virus, and possible interactions with other drugs, the agency said.

More information

The FDA has more about this approval.