WEDNESDAY, Oct. 17, 2007 (HealthDay News) -- Merck & Co.'s Isentress (raltegravir) has been approved by the U.S. Food and Drug Administration to treat HIV strains that are resistant to multiple antiretroviral drugs.
HIV is the virus that causes AIDS.
Isentress is the first of a new class of medicines that interferes with the enzyme that the HIV-1 virus needs to multiply. It's designed to be used in combination with other antiretroviral drugs in adults who have evidence of viral replication despite the use of antiviral drug therapy.
Besides reducing blood levels of HIV, Isentress may help increase white blood cells called CD4+ T cells, which help fight infections, the agency said.
Clinical testing revealed that some users developed elevated levels of a muscle enzyme, so the FDA advised caution in people who have muscle conditions or who use other drugs that can contribute to muscle problems.
The safety and effectiveness of Isentress haven't been evaluated in pregnant women or in people under age 16, and the drug's long-term effects haven't been studied, the agency said.
More information
The FDA has more about this approval.
