The randomized controlled trial is conducted among antiretroviral naive co-infected HIV and tuberculosis patients who receiving rifampicin-based antituberculous regimen fro at least 4 weeks butt not exceed 16 weeks before enrolment. All patients receive the same backbone regimen of stavudine (30 mg/40 mg twice daily)+ lamivudie 150 mg twice daily. They are randomized to receive nevirapine 400 mg/day twice daily vs efavirenz 600 mg/day at bed time. All patients are followed through 144 weeks after initiation of antiviral therapy. The primary objective are to compare the proportion of patient who achieve undetectable plasma HIV-1RNA<50 copies/ml at week 48. The previous reports demonstrated that the standard doses of both nevirapine and efavirenz coulde be used among co-infected HIV and tuberculosis patients who receiving rifampicin even though plasma levels are somewhat reduced by rifampicin. However, there have been not been a randomized control trial to compare these two regimens. Thus, this trial will provide the efficacy data between these two regimens.

Inclusion Criteria:

• Age 18-60 years
• Positive Serology for HIV-1
• Naïve to antiretroviral therapy
• Baseline CD4 cell counts <250 cells/mm3
• Diagnosed active tuberculosis by clinical features and/or positive acid fast stain and/or positive culture
• Received rifampicin at least 4 weeks but not exceed 16 weeks prior to enrollment
• Willing to participate and sign inform consent

Exclusion Criteria:

• Aspartate transferase enzymes (AST) or alanine transminase enzyme (ALT) >5 times of upper limit
• total bilirubin >3 times of upper limit
• serum creatinine) >2 times of upper limit
• pregnancy or lactation
• receiving immunosuppressive drugs
• receiving any drugs that may have drug-drug interaction with nevirapine and rifampicin
• chronic alcoholic drunken and intravenous drug users
• Previously received single dose of nevirapine to prevent mother to child transmission
• positive for serum cryptococcal antigen