Investigational Single-Pill HIV Treatment Matches Stribild's Efficacy

An experimental single-tablet regimen for treatment-naïve adults infected with HIV demonstrated non-inferiority to an FDA-approved combination pill in achieving undetectable viral load.

In a pair of recent Phase 3 studies, an experimental single-tablet regimen for treatment-naïve adults infected with HIV demonstrated non-inferiority to an FDA-approved combination pill in achieving undetectable HIV RNA levels, drugmaker Gilead Sciences Inc today announced.

The trials compared treatment-naïve HIV-1 patients receiving a once-daily, single-pill treatment comprised of elvitegravir 150 mg, cobicistat 150 mg, emtricitabine 200 mg, and tenofovir alafenamide 10 mg (E/C/F/TAF) to those taking the available once-daily, single-pill regimen consisting of elvitegravir 150 mg, cobicistat 150 mg, emtricitabine 200 mg, and tenofovir disoproxil fumarate 300 mg (Stribild).

In the first study, 93.1% of the 435 patients taking E/C/F/TAF had an undetectable viral load—defined as <50 copies of HIV-1 per mL—at week 48, compared to 92.4% of the 432 patients taking Stribild. In the second study, 91.6% of the 431 E/C/F/TAF patients achieved that primary objective at week 48, compared to 88.5% of the 435 Stribild patients.

Although both regimens had comparable safety profiles, E/C/F/TAF demonstrated more favorable renal and bone safety indicators than Stribild in the 2 trials.

“As individuals with HIV are living longer, there is a need for treatments that are not only highly effective, but also offer an improved safety profile,” said Norbert Bischofberger, PhD, Executive Vice President of Research and Development and Chief Scientific Officer for Gilead, in a press release. “Based on these Phase 3 results, we believe that the E/C/F/TAF single tablet regimen has the potential to optimize HIV therapy for a wide range of treatment-naïve patients.”

Based on the trial data, Gilead plans to submit a new drug application for E/C/F/TAF to the FDA by the end of 2014, the company said.