Gilead Sciences, Inc. announced Phase 3 clinical trial results from the pivotal Study 145 showing that its investigational antiretroviral elvitegravir, a novel oral integrase inhibitor being evaluated for the treatment of HIV-1 infection, was non-inferior to the integrase inhibitor raltegravir after 48 weeks of therapy in treatment-experienced patients. In the study, elvitegravir (150 mg or 85 mg) dosed once daily was compared to raltegravir (400 mg) dosed twice daily. Each integrase inhibitor was administered with a background regimen that included a ritonavir-boosted protease inhibitor (PI) and a second antiretroviral (ARV). These data are being presented in a late-breaker session at the 6th International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention (IAS 2011) in Rome, Italy.
“Because many treatment-experienced HIV patients have developed resistance to currently available antiretrovirals, identifying novel therapeutic options from the integrase inhibitor class is critical,” said Professor Jean-Michel Molina, MD, PhD, principal investigator, Hôpital Saint Louis in Paris and University of Paris 7. “These data suggest that elvitegravir may be an effective option for patients and may also have the potential for more convenient, once-daily dosing as part of combination HIV therapy.”
At 48 weeks of treatment in Study 145, 59 percent of patients receiving ritonavir-boosted elvitegravir achieved and maintained HIV RNA levels (viral load) of less than 50 copies/mL, compared to 58 percent of patients receiving raltegravir, based on the Time to Loss of Virologic Response algorithm (TLOVR). Discontinuation rates due to adverse events, and safety and resistance profiles were comparable in both arms of the study.
“These data are an important component of the regulatory filings for elvitegravir as both a stand-alone product and as part of the Quad single-tablet regimen in the United States and Europe in 2012,” said Norbert Bischofberger, PhD, Executive Vice President, Research and Development and Chief Scientific Officer, Gilead Sciences. “We believe elvitegravir, cobicistat and the Quad have the potential to be important new components of HIV therapy.”
Gilead’s investigational fixed-dose, single-tablet Quad regimen, which is currently in two Phase 3 studies, contains four Gilead compounds in a single pill: elvitegravir; cobicistat, an investigational pharmacoenhancing or “boosting” agent that increases blood levels of certain HIV medicines; Viread (tenofovir disoproxil fumarate); and Emtriva (emtricitabine). Phase 3 study results are expected in the third quarter of this year.
Date: July 20, 2011
Source: Gilead Sciences, Inc.
Filed Under: Drug Discovery