Study to Evaluate Switching From Regimens Consisting of a Ritonavir-boosted Protease Inhibitor Plus Emtricitabine/Tenofovir Fixed-Dose Combination to the Elvitegravir/Cobicistat/Emtricitabine/Tenofovir DF Single-Tablet Regimen in Virologically S

Study to Evaluate Switching From Regimens Consisting of a Ritonavir-boosted Protease Inhibitor Plus Emtricitabine/Tenofovir Fixed-Dose Combination to the Elvitegravir/Cobicistat/Emtricitabine/Tenofovir DF Single-Tablet Regimen in Virologically S