Glaxo’s Tivicay can be used by adults with HIV who have never been treated for the virus and those who have previously received drugs to attack the illness.
The medicine, known as dolutegravir, interferes with the enzymes necessary for HIV to multiply, the Food and Drug Administration said in a statement.
Tivicay reduced the HIV virus to undetectable levels in more people than Gilead Sciences’s Atripla, the world’s best-selling AIDS drug, in a clinical trial released last year.
London-based Glaxo’s medicine is used in combination with other anti-retroviral drugs. Merck & Co makes the first and only other inhibitor, Isentress, cleared in 2007 and with sales of $1.5bn last year.
About 1.1 million Americans have HIV, the virus that causes AIDS, and 50,000 are infected each year, according to the US Centres for Disease Control and Prevention. About 15,500 died in 2010, the FDA said in its statement.
The FDA is encouraging drugmakers to develop therapies for treatment-experienced HIV patients who develop resistance to medicines on the market. The HIV virus can mutate to outsmart treatments and leaves some patients, typically older ones that have had the disease for a while, few options for survival.
The agency drafted guidance in June that, once made final, will reduce clinical trials for HIV drugs to treat patients with resistance.