A Study to Compare the Effectiveness of Different Anti-HIV Drug Regimens in Keeping Levels of HIV in the Blood as Low as Possible

This study will look at different anti-HIV drug regimens to see which works best to keep the level of HIV (viral load) in the blood as low as possible during maintenance therapy. You will be assigned randomly (like tossing a coin) to 1 of 3 groups: Group 1: Didanosine plus stavudine plus hydroxyurea (ddI/d4T/HU). Group 2: Didanosine plus stavudine plus efavirenz (ddI/d4T/EFV). Group 3: This group of patients will remain on their current drug regimens. This study will last approximately 3 years; you will receive study medications for the duration of the study. Anti-HIV drug regimens that include protease inhibitors (PIs) are very good at lowering viral load. However, some patients have a rise in HIV levels while on PI maintenance. It may be possible to keep HIV levels low using another class of drugs for maintenance that are easier to take and less expensive than PIs. If viral load increases while a patient is taking this second group of drugs, it may be possible to restart the PI drug regimen and again decrease HIV levels.