The objective of this study is to evaluate the safety and efficacy of a regimen containing cobicistat-boosted atazanavir (ATV+COBI) plus emtricitabine/tenofovir disoproxil fumarate (Truvada®; FTC/TDF) fixed-dose combination (FDC) versus ritonavir-boosted atazanavir (ATV+RTV) plus FTC/TDF FDC in HIV-1 infected, antiretroviral treatment-naive adults.