Gilead’s Quad Phase 3 clinical study in treatment-naïve HIV-1 patients meets 48-week primary objective

Gilead Sciences, Inc. (Nasdaq: GILD) today announced that the second pivotal Phase 3 clinical trial (Study 103) of its investigational fixed-dose, single-tablet "Quad" regimen of elvitegravir, cobicistat, emtricitabine and tenofovir disoproxil fumarate, being evaluated for HIV-1 infection in treatment-naïve patients, met its primary objective of non-inferiority at week 48 as compared to ritonavir-boosted atazanavir plus Truvada^® (emtricitabine/tenofovir disoproxil fumarate) based on the proportion of subjects who achieved HIV RNA levels (viral load) of less than 50 copies/mL.

“The 90 percent response rate observed on the Quad arm in this study is an unprecedented result and speaks to the potency, safety and convenience of an integrase-based single-tablet regimen”

The primary endpoint analysis indicated that 90 percent of patients in the Quad arm compared to 87 percent in the ritonavir-boosted atazanavir plus Truvada arm (95 percent CI for the difference: -1.9 percent to 7.8 percent) achieved HIV RNA of less than 50 copies/mL through week 48. The predefined criterion for non-inferiority was a lower bound of a two sided 95 percent CI of -12 percent. The discontinuation rate due to adverse events was higher in the ritonavir-boosted atazanavir arm (5.1 percent) as compared to the Quad (3.1 percent). This difference was driven primarily by elevated bilirubin levels observed in the ritonavir-boosted atazanavir arm. Other adverse events and laboratory abnormalities were similar between the two arms. Gilead plans to submit these data for presentation at a scientific conference early next year.

"The 90 percent response rate observed on the Quad arm in this study is an unprecedented result and speaks to the potency, safety and convenience of an integrase-based single-tablet regimen," said Norbert Bischofberger, PhD, Executive Vice President, Research and Development and Chief Scientific Officer, Gilead Sciences. "Based on the availability of data from both pivotal Studies 102 and 103, we are now working toward filing for U.S. regulatory approval of the Quad by the end of the year."