New label warnings are being added to the hepatitis C drug Victrelis by federal health officials, who indicate that combining it with certain HIV drugs may cause both treatments to lose effectiveness.
The FDA issued a safety announcement on April 26, warning that Victrelis should not be used with the HIV drugs Reyataz, Prezista and Kaletra. All three drugs are Norvir-boosted HIV protease inhibitors.
According to the FDA, research has shown that when the drug combinations are taken, the blood levels of the HIV drugs and Victrelis dropped from 49 to 59%.
The FDA first warned of the problem in a Victrelis drug safety communication issued in February. At the time, the FDA recommended that doctors closely watch patients taking the affected drug combinations and discuss the agency’s findings with those patients. Now the FDA is officially recommending that the drugs not be used together.
Healthcare professionals are being warned that this could cause a resurgence of the hepatitis C virus and HIV in patients that had previously improved under treatment.
Victrelis (boceprevir) is a hepatitis C protease inhibitor used to treat chronic hepatitis C infections in adults. It was approved for use by the FDA in May 2011. Merck, the makers of Victrelis, advised against using it with HIV drugs and warns that Victrelis is not indicated for use in patients who have both HIV and hepatits C.