Long-term studies have found that Isentress (raltegravir) is both safe and effective in suppressing HIV among adult patients coinfected with hepatitis B, C or both, the BusinessWire reports. Merck presented results from a post-hoc, subgroup analysis of three randomized, double-blind, Phase III clinical trials of the integrase inhibitor in both treatment-experienced (BENCHMRK-1 and -2 studies) and treatment-naive (STARTMRK study) participants at the 11th International Congress on HIV and Drug Therapy in HIV Infection in Glasgow.

The 240-week STARTMRK study involved 563 treatment-naive people with HIV receiving either Isentress or Sustiva (efavirenz), each in combination with Truvada (tenofovir/emtricitabine). Thirty-four people in the two treatment groups were coinfected with hepatitis B and/or C. In the Isentress group, five people had hepatitis C virus (HCV) and 13 hepatitis B virus (HBV).

BENCHMRK-1 and -2 were 156-week studies that included 699 treatment-experienced HIV patients with triple-class resistance who were failing HIV therapies. They received either Isentress or a placebo, each in combination with an optimized background therapy. Then, an open-label study continued after the study’s completion in which patients took Isentress with combination therapy. In the two treatment groups, 114 people were coinfected with hep B, C or both. In the Isentress arm, 27 had hepatitis C, 26 had hepatitis B and four had both hepatitis viruses.

The patients in the Isentress arm of the STARTMRK study experienced high rates of undetectable viral loads at 240 weeks: 90.9 percent of the coinfected patients and 89.1 percent of those living with just HIV. At 91.7 percent, the rate was similar for coinfected patients in the efavirenz arm, although just 80 percent of monoinfected patients maintained an undetectable viral load in that arm.

The BENCHMRK-1 and -2 trials examined undetectable viral loads at 156 weeks. In the Isentress arm, 62.3 percent of coinfected patients and 57.9 percent of monoinfected patients were undetectable. Meanwhile, the respective rates for those in the placebo arm were 14.7 percent and 26.3 percent. In the open-label extension of the study, patients who reached an undetectable viral load at 240 weeks were the following: 50 percent of coinfected patients and 52.5 percent of monoinfected patients; and in the placebo, a respective 14.7 percent and 20.5 percent.

To read the BusinessWire report, click here.