Multicenter, Randomized, Double-Blind, Double-Dummy, Phase 3 Study of the Safety and Efficacy of Elvitegravir Versus Raltegravir

The purpose of this study is to compare the safety, tolerability and efficacy of a regimen containing once-daily elvitegravir (EVG) versus twice-daily raltegravir (RAL) added to a background regimen (1 fully-active ritonavir (RTV)-boosted protease inhibitor (PI) plus 1 or 2 additional antiretroviral (ARV) agents) in HIV-1 infected, ARV treatment-experienced adults who have documented resistance, or at least six months experience prior to screening with two or more different classes of ARV agents. Participants will be randomized in a 1:1 ratio to receive EVG plus background regimen (Elvitegravir group), or raltegravir plus background regimen (Raltegravir group). Due to known drug interactions, participants in the Elvitegravir group receiving RTV-boosted atazanavir (ATV) or RTV-boosted lopinavir (LPV) as part of their background regimen will receive elvitegravir at a lower dose (85 mg).