Fulfilling a long-held goal of AIDS researchers, federal regulators Wednesday approved the first anti-HIV drug that requires patients to take only one pill once a day.
The drug, called Atripla, combines the three most widely prescribed HIV drugs into one pill, providing patients with a simpler medication regimen.
Atripla could slow HIV drug resistance by helping patients avoid missing doses. It could also lower their out-of-pocket expenses by reducing the number of co-pays under their insurance.
The approval is "a landmark in the treatment of HIV/AIDS," said Andrew C. von Eschenbach, acting commissioner of the Food and Drug Administration, in announcing the approval.
The development of Atripla is the first time that two pharmaceutical manufacturers have combined their HIV drugs into one pill.
The salmon-colored pill, about the size of a multivitamin, contains Viread and Emtriva, produced by Gilead Sciences Inc. of Foster City, Calif., and Sustiva, manufactured by Bristol-Myers Squibb Co. of New York.
"The concept that two rival drug companies were able to overcome marketing, legal and manufacturing challenges is a really good sign for potential future activities," said Craig E. Thompson, executive director of AIDS Project Los Angeles. "This is a new level of cooperation."
The companies said that Atripla would be available to consumers within seven business days and that its wholesale price would be $1,150.88 for a 30-day supply, the same price as the drugs sold separately.
The three drugs, whose generic names are tenofovir, emtricitabine and efavirenz, are reverse transcriptase inhibitors, which block an enzyme necessary for HIV replication. Reverse transcriptase inhibitors were the first family of HIV drugs developed and are still the most widely prescribed family of drugs for newly diagnosed patients.
When a patient develops resistance to one or more of the drugs, physicians typically add a second family of drugs called protease inhibitors. Experts said companies were looking for ways to incorporate them into the pill.
Sustiva and Emtriva are available in a once-daily pill called Truvada, so many patients take two pills a day.
But studies of various types of drugs have shown that "the fewer pills you can get, the better the compliance," said Dr. Joseph Cadden of USC's Keck School of Medicine. "That's a key factor in AIDS, where you have to have an adherence of 95% plus" to prevent drug resistance.
The efforts to produce the pill may be especially important to HIV-positive people who remember the early days of HIV drug cocktails when patients took 30 or more pills daily.
"People were talking about once-a-day as a magical, wonderful, far-off moment," Thompson said. "It was one of those things we were waiting for, and we've done a great job in getting there."
The approval came as a result of an FDA program begun last year to accelerate development of combination drugs for treating AIDS. Combination drugs are considered highly desirable for foreign aid efforts, like the President's Emergency Plan for AIDS Relief, or PEPFAR, because they are easier for people in developing countries to procure.
The program does not require efficacy testing of the drugs if they have been approved individually. But the manufacturers must show that a combination pill yields the same level of drugs in the bloodstream as do the individual products.
That requirement proved a small hurdle for the two companies after Gilead researchers found that the drugs interacted when they were combined in a pill, impeding their absorption by the body. Scientists eventually overcame the problem by separating the components with a thin membrane that dissolved when the pill was swallowed.
Representatives of Gilead and Bristol-Myers Squibb said they would work with Merck & Co. to get Atripla approved for distribution in PEPFAR and a U.N. AIDS program. Merck owns the distribution rights for efavirenz -- which it calls Stocrin -- in much of the world.
Experts predicted that the drug would be sold to those programs for about $800 per month, roughly four times the price of other regimens.
On June 30, the FDA tentatively approved a combination pill containing the anti-HIV drugs zidovudine, lamivudine and nevirapine, and manufactured by Aurobindo Pharma of Hyderabad, India. Because of patent issues, that pill cannot be marketed in the United States, but FDA approval allows its use in PEPFAR programs.
Times staff writer Heather Gehlert in Washington contributed to this report.