FDA, Merck & Co., Inc. Warn Against Using Victrelis With Some HIV Drugs

The U.S. Food and Drug Administration said Thursday the use of Merck & Co.'s (MRK) Hepatitis C drug Victrelis with certain types of HIV medicines may reduce effectiveness of both types of treatments. Victrelis was approved last year to treat Hepatitis C, a liver disease caused by infection with the hepatitis C virus, which is transmitted through contaminated blood. Although Victrelis wasn't approved for use in people who are infected with both HIV, another virus transmitted through contaminated blood, and Hepatitis C, many patients have both diseases. FDA's announcement was prompted by the results of a small study conducted by Merck that specifically looked at the concentrations, or blood levels, of Victrelis when used with three so-called ritonavir-boosted HIV drugs. Treatments for both Hepatitis C and HIV include several drugs meant to be administered together.