Efficacy and Safety of VICRIVIROC in HIV-Infected Treatment-Naïve Subjects (Study P04875)

Inclusion Criteria: * Adult subjects at least 18 years old or minimum age that defines an adult as determined by local regulatory authorities or legal requirements) of either sex or any race with CCR5-tropic HIV infection. * Cumulative lifetime anti-retroviral therapy exposure of at most 4 weeks (with the exception of prophylaxis to prevent mother-to-child transmission, and in this case, if no antiretroviral resistance is expected to have developed) and none in the 8 weeks preceding randomization. * A CD4 cell count of at least 100 cells/(cubic mm) at Screening (or as specified by local treatment guidelines). * HIV ribonucleic acid (RNA) must be at least 2000 copies/mL at Screening. * Subjects should meet International AIDS Society (IAS), Department of Health and Human Services (DHSS), or local recommendations for initiation of antiretroviral therapy (ART). * Platelet count must be at least 50,000/microL, hemoglobin at least 8 g/dL, absolute neutrophil count at least 1000/microL, serum creatinine \<2.0 mg/dL (154 micromol/L), and SGOT/SGPT (serum glutamic oxaloacetic transaminase/serum glutamic pyruvic transaminase) at most 3 x upper limit of normal at Screening. Other clinical laboratory tests must be within normal limits or clinically acceptable to the investigator. * Female subjects of childbearing potential must be using a medically accepted method of birth control prior to Screening and agree to continue its use during the study, or must have been surgically sterilized. * Female subjects of childbearing potential must have a negative serum beta-hCG (human chorionic gonadotropin) pregnancy test at Screening and a negative urine beta-hCG pregnancy test on Day 1 prior to dosing. Exclusion Criteria: * Female subjects of childbearing potential who are breastfeeding, pregnant, or planning to become pregnant. * Subjects with intercurrent illness, vaccinations, or who have used immunomodulators (within the 4 week period prior to randomization) that could influence plasma HIV RNA levels. * CXCR4 or dual-mixed (CXCR4 and CCR5) tropism. * Subjects with primary resistance mutations to any of proposed components of the study arms. * Subjects with active opportunistic infection or malignancy. * Subjects with seizure disorder requiring ongoing anti-seizure therapy or with a history of a seizure disorder who are, in the judgment of the investigator, at risk for seizures.