New HIV Drug for Adults
FDA approved on August 6, 2007, the first drug in a new class designed to slow the advancement of HIV. Maraviroc, an antiretroviral drug for use in adults with HIV, is sold under the trade name Selzentry, and is distributed by New York-based Pfizer Inc. The drug received priority review by FDA.
How maraviroc works
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. CCR5 is a protein on the surface of some types of immune cells. Among patients who have previously received HIV medications, approximately 50 to 60 % have circulating CCR5-tropic HIV-1.
Maraviroc is approved for use in combination with other antiretroviral drugs for the treatment of adults
- with CCR5-tropic HIV-1
- who have been treated with other HIV medications
- who have evidence of elevated levels of HIV in their blood (viral load)
Safety and effectiveness
FDA's approval of maraviroc is based on 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.
The most common adverse events reported with maraviroc were cough, fever, upper respiratory tract infections, rash, musculoskeletal symptoms, abdominal pain, and dizziness. The product label includes a boxed warning about liver toxicity (hepatoxicity) and a statement in the Warnings/Precautions section 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. FDA recommends that HIV-positive women should not breastfeed, whether or not they are on antiretroviral medications.
This article appears on FDA's Consumer Updates page, which features the latest on all FDA-regulated products.
Date Posted: August 7, 2007