FDA Approves Maraviroc (Selzentry) for Refractory HIV in Adults

ROCKVILLE, Md., Aug. 7 -- The FDA has approved maraviroc (Selzentry), the first of a new class of antiretroviral drugs that slows advancement of HIV by blocking its entry into cells.
Maraviroc was approved for use in combination with other antiretroviral drugs in adult HIV patients with CCR5-tropic HIV. The FDA said the drug can be used in patients who have evidence of elevated virus in their blood following treatment with other antiretroviral drugs.
Rather than fighting HIV inside white blood cells, maraviroc prevents the virus from entering uninfected cells by blocking the predominant route of entry, the CCR5 co-receptor, which is on the surface of some immune cells.
The FDA said that 50% to 60% of patients who have previously received HIV treatment have circulating CCR5-tropic HIV-1.
The approval of maraviroc emerged from safety and effectiveness data from two double-blind placebo-controlled studies. The 1,076 clinical trial participants were selected because they still showed evidence of HIV-1 in their blood, despite treatment with other HIV medications. A blood test for CCR5 tropic HIV was used during clinical trials to identify patients appropriate for treatment with maraviroc. (See IAS: CCR5 Inhibitors Eagerly Awaited for HIV Therapy)
The product label includes a boxed warning about liver hepatoxicity and a statement elsewhere about the possibility of heart attacks.
The safety and effectiveness of maraviroc have not been established in adult and pediatric patients who have never been treated with any other HIV drug. Additionally, the drug has not been tested or studied in pregnant women. The FDA recommends that HIV positive women should not breast feed.
The most common adverse events reported with maraviroc were cough, fever, upper respiratory tract infections, rash, musculoskeletal symptoms, abdominal pain, and dizziness.
Maraviroc will be marketed by Pfizer.