PILOT STUDY OF NOVEL COMBINATION OF MARAVIROC +ATAZANAVIR/RITONAVIR VS ATAZANAVIR/RITONAVIR +EMTRICITABINE/TENOFOVIR FOR THE TREATMENT OF TREATMENT NAÏVE HIV-INFECTED PATIENTS WITH R5 HIV-1

INTERVENTION: Product Name: Maraviroc Product Code: UK‐427,857 Pharmaceutical Form: Tablet INN or Proposed INN: Maraviroc CAS Number: 376348‐65‐1 Current Sponsor code: UK427,857 Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 150‐ Trade Name: Truvada Pharmaceutical Form: Tablet INN or Proposed INN: emtricitabine CAS Number: 143491‐57‐0 Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 200‐ INN or Proposed INN: Tenofovir disoproxil CAS Number: 147127‐20‐6 Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 245‐ CONDITION: TREATMENT OF TREATMENT NAÏVE HIV‐INFECTED PATIENTS WITH R5 HIV‐1 ; MedDRA version: 9.1 Level: LLT Classification code 10020161 Term: HIV infection PRIMARY OUTCOME: Main Objective: To examine if the combination of maraviroc (SelzentryTM, Celsentri®) and atazanavir/ritonavir is effective for the treatment of treatment‐naïve HIV‐1 infected subjects as measured by the percentage of subjects with HIV‐1 RNA below the limits of assay detection (<50 copies of HIV‐1 RNA per milliliter of plasma) at 48 weeks. Primary end point(s): The percentage of patients with plasma HIV‐1 RNA <50 copies/mL in each treatment arm at 48 weeks. Secondary Objective: 1. Safety and tolerability;; 2. To assess the viral kinetics within the first 2 weeks in the first 15 patients in each; treatment arms (US sites only);; 3. To evaluate the pharmacokinetics of maraviroc in a subset of patients (n=15)enrolled in the maraviroc treatment arm (US sites only);; 4. To assess virologic response over time;; 5. To assess immunological response (CD4 and CD8 counts) over time;; 6. To examine the evolution of viral resistance and/or tropism in treatment failure patients only. INCLUSION CRITERIA: Subjects must meet all of the following inclusion criteria to be eligible for enrollment into the study: 1. Provide a signed and dated written Informed Consent Document indicating that the subject (or a legally acceptable representative) has been informed of all pertinent aspects of the trial. 2. At least 16 years of age (or minimum age as determined by local regulatory authorities or as legal requirements dictate) at the Screening Visit. 3. HIV‐1 RNA viral load of =1,000 copies/mL measured at the Screening Visit. 4. CD4 count =100 cells/mm3 at Screening. 5. Have only R5 HIV‐1 at Screening as verified by the Monogram Bioscience Trofile assay with enhanced sensitivity. 6. A negative urine pregnancy test at the Baseline Visit, prior to receiving the first dose of study medication, for Women of Child Bearing Potential (WOCBP). NOTE: WOCBP include any female who has experienced menarche and who has not undergone successful surgical sterilization or