A Trial to Compare Raltegravir Versus Nevirapine as Anchor Drug for HIV+ Chinese IDUs on Methadone Maintenance

This is a pilot randomized controlled Open-label trial to compare raltegravir and nevirapine as anchor Drug in combined antiretroviral therapy(ART) for ART-naive HIV+ Chinese injection drug users who are also on methadone maintenance therapy. The investigators hypotheses include: 1. In raltegravir arm compared with nevirapine arm, fewer patients will require methadone dose adjustment to abate methadone withdrawal symptoms. Also the average methadone dose to achieve adequate serum methadone concentrations in patients on the raltegravir-based regimen will be lower compared to that of patients on the nevirapine-based regimen. 2. Clinical outcomes in terms of viral suppression, CD4 recovery and occurrence of opportunistic infections will be comparable in the two arms at 6 months and one year. 3. Patients in the raltegravir arm will have a similar or better side effect profile, retention rate, and treatment adherence compared to those in the nevirapine arm.