Two Phase III trials show Genvoya (elvitegravir, cobicistat, emtricitabine and TAF) is non-inferior to Stribild (elvitegravir, cobicistat, emtricitabine and TDF) in HIV-Gilead Sciences

Gilead Sciences has announced 96-week results from two Phase III studies (Study 104 and study 111) evaluating its once-daily single tablet regimen Genvoya (elvitegravir 150 mg, cobicistat 150 mg, emtricitabine 200 mg and tenofovir alafenamide 10 mg, or E/C/F/TAF), for the treatment of HIV-1 infection in treatment-naïve adults. Genvoya was found to be statistically non-inferior to Stribild (elvitegravir 150 mg, cobicistat 150 mg, emtricitabine 200 mg and tenofovir disoproxil fumarate 300 mg, or E/C/F/TDF), based on percentages of patients with HIV-1 RNA levels less than 50 copies/mL. Patients receiving Genvoya also had improved renal and bone laboratory parameters compared to those treated with Stribild.

In the combined analysis of Studies 104 and 111, a total of 1,733 treatment-naïve adults with HIV were randomised to receive either Genvoya or Stribild. At 96 weeks, 86.6% of patients taking Genvoya and 85.2% of patients taking Stribild achieved HIV-1 RNA levels less than 50 copies/mL. The analysis found that the rate of virologic success between the two regimens was similar across patient subgroups (age, gender, race, baseline HIV-1 RNA level and baseline CD4 count). Discontinuations due to adverse events were low in both treatment arms. The data were presented at the 15th European AIDS Conference.

Comment: Tenofovir alafenamide (TAF) is a prodrug of tenofovir, the active agent in Viread (tenofovir disoproxil fumarate or TDF). Studies have identified a dose of TAF that is ten times lower than Viread. Gilead hopes that this smaller dosage of TAF may enable the development of new fixed-dose combinations and single tablet regimens for HIV therapy that are not feasible with Viread.