Second Phase 3 Trial Update of Gilead's Antiretroviral Quad Regimen for HIV

Gilead Sciences announced full results from the second pivotal Phase 3 clinical trial (Study 103) of its Quad once-daily single tablet regimen of elvitegravir, cobicistat, emtricitabine and tenofovir disoproxil fumarate for the treatment of HIV. The study found that the Quad was non-inferior to a protease-based regimen of ritonavir-boosted atazanavir (ATV/r) plus Truvada (emtricitabine/tenofovir disoproxil fumarate) at 48 weeks of therapy among HIV-1 infected treatment-naïve adults.

Study 103 was a randomized (1:1), double-blind trial comparing the efficacy, safety and tolerability of the Quad (elvitegravir 150mg/cobicistat 150mg/emtricitabine 200mg/tenofovir disoproxil fumarate 300mg) (n=353) versus atazanavir 300mg boosted by ritonavir 100mg (ATV/r) plus Truvada (n=355) among HIV-infected treatment-naïve adults with baseline HIV RNA levels >5,000 copies/mL.

At 48 weeks of treatment in Study 103, Quad demonstrated comparable efficacy to the atazanavir-based regimen, with 90% of Quad patients compared to 87% of patients receiving ATV/r plus Truvada achieving HIV RNA (viral load) <50 copies/mL, using the FDA snapshot algorithm (95% CI for the difference: -1.9% to 7.8%; predefined criterion for non-inferiority was a lower bound of a two sided 95% CI of -12%). Among patients with baseline HIV RNA >100,000 copies/mL, Quad demonstrated similar efficacy, with 85% of Quad patients compared to 82% of patients receiving ATV/r plus Truvada achieving viral load <50 copies/mL.

The Quad contains four Gilead compounds in a complete once-daily, single-tablet regimen: elvitegravir, an integrase inhibitor; cobicistat, a “boosting” agent that enables elvitegravir once-daily dosing; and Truvada. 

For more information call (800) GILEAD-5 or visit www.gilead.com.