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

The background regimen will be constructed by the investigator based on viral resistance testing. The fully active PI will be defined by phenotypic resistance analysis. For phenotypic susceptibility, fully active is defined as being below the lower clinical or biological cutoff. Participants are required to take their ritonavir dose based on the dosing schedule indicated in the prescribing information for the PI; no additional ritonavir is required to be taken with EVG. No other marketed PIs are allowed as part of the background regimen due to unknown drug interactions. The second agent can be one nucleoside or nucleotide reverse transcriptase inhibitor (NRTI), etravirine, maraviroc, or T-20. However, the second agent must not include an integrase inhibitor; the nonnucleoside reverse transcriptase inhibitors efavirenz, nevirapine, or delavirdine (due to unknown drug interactions); or the fixed-dose combination therapies Atripla® or Trizivir® (abacavir sulfate/lamivudine/zidovudine). The second agent may or may not be fully active (except in Spain, where participants have to receive a fully active second agent, as requested by the Spanish regulatory agency). If the M184V/I reverse transcriptase (RT) mutation is present on the screening genotype report and an NRTI is used as the second agent, then either FTC or LAM may be added as a third agent in the background regimen to maintain the M184V/I mutation. In this situation only, the fixed-dose combination therapies Combivir®, Truvada®, or Epzicom/Kivexa® may be prescribed as the combined second and third agents of the background regimen. After Week 96, participants will continue to take their blinded study drug and attend visits until treatment assignments are unblinded, at which point they will be given the option to participate in an open-label EVG extension phase of the study.