A Phase 2b, Safety and Efficacy Study of Boceprevir in Patients Coinfected With HIV and Hepatitis C (P05411 AM4)

Inclusion Criteria: * \>=18 and \<=65 years of age * Body weight \>=40 and \<=125 kg * Documented history of HIV infection for greater than 6 months prior to Day 1 * On an optimized anti-retroviral treatment regimen (OTR) with stable HIV disease with CD4 \>=200 cells/µL and HIV-1 RNA viral load \<50 copies/mL * Documented chronic hepatitis C (CHC) genotype 1 infection (greater than 6 months prior to Day 1) * Use of acceptable methods of contraception 2 weeks prior to Day 1 and at least 6 months or longer after treatment * Liver biopsy with histology consistent with CHC and no other etiology Exclusion Criteria: * Participants who received prior treatment for hepatitis C other than herbal remedies except those with known hepatotoxicity * Coinfected with hepatitis B virus (Hepatitis B surface antigen (HBsAg) positive) and/or demonstrating signs and symptoms consistent with concomitant infection * Evidence of decompensated liver disease * Participants who have changed their anti-retroviral regimen within the last 3 months prior to Day 1 or had first initiated anti-retroviral therapy within the last 6 months prior to Day 1 * Use of certain HIV medications will not be allowed. Medications will be reviewed by the Investigator * History of clinically significant opportunistic infections (except oral thrush) within the last year prior to Day 1 * Current evidence of substance abuse within 3 years of the Screening Visit * History of a clinical diagnosis within the past 6 months of substance abuse prior to Day 1 * Participants receiving opiate agonist substitution therapy but not enrolled in an opiate substitution maintenance program * History of marijuana use deemed excessive by the Investigator * Infected with HIV-2 * Use of any HIV protease inhibitor without the coadministration of ritonavir within one month of Day 1 and throughout the period of the trial * Participants receiving any of the following medication(s) within 2 weeks prior to the Day 1 visit: alfuzosin, antiarrhythmics (amiodarone, bepridil, flecainide, propafenone, and quinidine), ergot derivatives, cisapride, lovastatin, simvastatin, pimozide, triazolam, and orally administered midazolam. Key Laboratory Exclusion Criteria: * Hematologic, biochemical, and serologic criteria (growth factors may not be used to achieve trial entry requirements): * Hemoglobin \<11 g/dL for females and \<12 g/dL for males * Neutrophils \<1500/mm\^3 (blacks/African-Americans: \<1200/mm\^3) * Platelets \<100,000/mm\^3 * Direct bilirubin \>1.5 x ULN (upper limit of normal) of the laboratory reference range. Total bilirubin \>1.6 mg/dL unless history of Gilbert's disease or antiretroviral regimen contains atazanavir. If Gilbert's disease is the proposed etiology, this must be documented in the participant's chart * Alpha fetoprotein (AFP): * AFP \>100 ng/mL OR * AFP 50 to 100 ng/mL (requires a liver ultrasound and participants with findings suspicious for hepatocellular carcinoma are excluded)