Raltegravir approved for treatment-naive patients

The FDA has approved a twice-daily formulation of 400 mg raltegravir (Isentress, Merck) for treatment-naive patients with HIV. The treatment can be given with or without food.

The approval followed a head-to-head trial that compared the safety and efficacy of raltegravir 400 mg twice daily plus emtricitabine (Emtriva, Gilead) plus tenofovir (Viread, Gilead) compared with efavirenz (Sustiva, Bristol-Myers Squibb) 600 mg plus emtricitabine plus tenofovir.

The proportion of patients who reached HIV RNA levels <50 copies/mL in the raltegravir group was 87%, compared with 82% of patients who reached the same level in the efavirenz group. The difference in the proportions was 4.7% (95% CI, –1.3%-10.6%).

The approval included revisions to the package insert for the drug.

A warning regarding use of raltegravir and rifampin was added to the drug interactions section of the label. The warning states that the use of rifampin may result in reduced concentrations, and suggests that physicians consider doubling the dose in patients taking both medications.

Bach-Yen Nguyen, Merck’s senior director of clinical research, said in an interview that another change in the packaging includes some postmarketing data that noted paranoia and anxiety in some patients. However, she said that those adverse event rates were similar to those seen with comparable medications.