Study 104 is one of two randomised, double-blind Phase III trials designed to compare a single tablet regimen of TAF to Gilead’s existing drug, Stribild, among treatment-naïve HIV-1 infected adults.
Gilead Sciences chief scientific officer and research and development executive vice president Dr Norbert Bischofberger said; "We believe that TAF’s smaller milligram size has the potential to offer safety and tolerability advantages over existing therapies, and may enable the creation of new single tablet regimens for HIV."
In each study, 840 HIV-1 infected patients with viral load of 1,000 copies/ml or more will be randomised to receive a once-daily tablet containing TAF 10mg; elvitegravir 150mg; cobicistat 150mg and emtricitabine 200mg (n=420), or Stribild (n=420).
The primary endpoint of both studies will be the percentage of patients with a viral load of less than 50 copies/ml after a 48-week treatment period based on the FDA-defined snapshot analysis.
Secondary endpoints include the number of patients with viral load of less than 20 copies/ml and 200 copies/ml at week 48 and week 96 respectively based on the FDA-defined snapshot analysis.
Other secondary endpoints are the section of patients with a viral load of less than 50 copies/ml at week 48 as per FDA Time to Loss of Virologic Response analysis, the proportion of patients with viral load less than 50 copies/ml at week 96 as measured by the FDA snapshot and TLOVR analyses and change from baseline in CD4+ cell count at weeks 48 and 96.
The company expects to commence the second Phase III trial, Study 111, within the next few months.