A Trial of Observed Long-acting, Anti-HIV Treatment With a Monoclonal CCR5 Antibody (PRO 140) as an Adjunct to a New, Optimized, Oral Antiretroviral Regimen in HIV-infected Injection Drug Users With Viral Rebound and Documented Poor Adherence

Key Inclusion Criteria: 1. Only R5 virus 2. HIV-1 RNA \> 1,000 copies/mL but \< 100,000 copies/mL 3. CD4+ lymphocyte counts \> 100 cells/μL 4. Non-prescription recreational drug use within the previous 6 months Key Exclusion Criteria: 1. Females who are pregnant (positive blood test), lactating, or breastfeeding, or who plan to become pregnant during the study 2. Prior use of any CCR5 entry inhibitors 3. History of any acquired immune deficiency syndrome (AIDS)-defining illness