Gilead Sciences, Inc. (Nasdaq:GILD) today announced full clinical trial results from a pivotal Phase 3 study evaluating cobicistat, a pharmacoenhancing or “boosting” agent for HIV therapy, compared to ritonavir, which is currently the only agent used to boost certain antiretroviral treatment regimens. The study found that an HIV regimen containing a cobicistat-boosted protease inhibitor was non-inferior to a regimen containing a ritonavir-boosted protease inhibitor at 48 weeks of therapy. The findings will be presented today in an oral session (abstract #TUAB0103) at the 19th International AIDS Conference (AIDS 2012) taking place in Washington, D.C.
“These data demonstrate that cobicistat may be an effective option for boosting the potency of HIV regimens that are based on protease inhibitors,” said Joel Gallant, MD, MPH, Professor of Medicine and Epidemiology at Johns Hopkins University, and principal investigator of the study.
In the trial (Study 114), treatment-naïve adult patients received either cobicistat or ritonavir for 48 weeks. All patients also received atazanavir (a protease inhibitor) plus Truvada
(emtricitabine and tenofovir disoproxil fumarate). At 48 weeks, the study found that 85 percent of patients on the cobicistat-containing regimen compared to 87 percent of patients on the ritonavir-containing regimen achieved HIV RNA (viral load) levels less than 50 copies/mL, based on the U.S. Food and Drug Administration (FDA) snapshot algorithm (95 percent CI for the difference: -7.4 percent to +3.0 percent; predefined criterion for non-inferiority was a lower bound of a two-sided 95 percent CI of -12 percent). Twenty-five patients (7 percent) discontinued treatment due to adverse events in each arm of the study.
“We believe that cobicistat has a central role to play in boosting protease-based HIV therapies,” said Norbert Bischofberger, PhD, Executive Vice President, Research and Development and Chief Scientific Officer, Gilead Sciences. “In addition to our marketing application for cobicistat that is currently under FDA review, we are partnering with other pharmaceutical companies to develop two new fixed-dose combinations that combine cobicistat with some of today’s most prescribed protease inhibitors.”