Merck’s once-daily HIV drug meets primary efficacy endpoint in phase 3 study

The phase 3 ONCEMRK study, which is assessing Isentress in earlier untreated HIV-1 infected adults, met its primary efficacy endpoint by demonstrating that 1200mg of Isentress once-daily was statically non-inferior to the approved 400mg twice-daily formulation.

In both arms treatment with Isentress was given alongside Gilead Sciences’ Truvada, and efficacy was evaluated in several patients achieving HIV-1 RNA <40 copies/mL at week 48.

Merck noted that secondary endpoints of tolerability and immunologic efficacy, as measured by change from baseline in CD4 cell counts at week 48, were also comparable between the two treatment arms.

Later this year, the company plans to submit licensing applications for the new formulation to the Food and Drug Administration and the European Medicines Agency.

Isentress is Merck’s integrase inhibitor for the treatment of HIV-1 infection in adult and pediatric patients ages four weeks and older and weighing about 3 kg as part of combination HIV therapy.

It inhibits the insertion of HIV-1 DNA into human DNA by the integrase enzyme and has showed quick antiviral activity.

Isentress is approved as part of combination therapy in 115 countries to treat HIV-1 infection in adult patients.

Merck has also won approval for Isentress, in combination therapy, for use in children and adolescents with HIV-1 ages two years and older in 64 countries.

Isentress oral suspension for infants at least four weeks of age is approved in 34 nations.

Image: Pützerturm, a landmark of the headquarters of Merck KGaA, Darmstadt, Germany. Photo: courtesy of Merck KgaA.