• Virologic: A. Plasma viral load B. Tissue viral load (CNS, lymphoid tissues, genital tract) C. HIV DNA (proviral) levels in circulating mononuclear cells D. Phenotypic and genotypic antiretroviral drug resistance [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
  
• Immunologic: A. Evaluation of CD4, CD8, CD45RA, CD45RO phenotypes and defined activation markers B. Evaluation of the diversity and persistence of the T cell repertoire (CD4+, CD8+) in the circulation and lymphoid tissues [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
  
• Immunologic: C. Functional CD4+ cellular assays (class II MHC tetramers) D. Thymic regeneration as studied by the exclusion circle assay E. Evolution of Western blot banding patterns F. Evolution of anti-HIV neutralizing antibody levels [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
  
• Clinical: A. Minor opportunistic infections or AIDS-defining conditions B. Death C. Clinical or laboratory adverse events D. Evaluation of adherence to therapy E. Evaluation of lipodystrophy [ Time Frame: Throughout study ] [ Designated as safety issue: Yes ]
  

Studies have suggested that an antiretroviral drug regimen of the non-nucleoside agent efavirenz (EFV) in combination with two nucleoside analogues is effective at achieving maximal viral suppression. This provides an alternative treatment to that of the more toxic PI-containing regimen. This trial examines whether a nonPI regimen with EFV is more beneficial than a PI-containing regimen when each is used in combination with the same two nucleoside analogues. A second part of the study looks at whether the addition of IL-2 may offer immunologic benefits as a co-administered drug.

Patients are randomized to initiate antiretroviral therapy of a PI-based (stavudine/didanosine/ritonavir [RTV]/indinavir [IDV]) or nonPI-based (stavudine/didanosine/EFV) regimen. Within these treatment arms, they are stratified according to a positive or negative p24 antigen result. At Week 16, patients not achieving maximal viral suppression (lower than 50 copies/ml) have the option to add abacavir (ABC) or other drugs as intensification therapy. Those achieving virologic suppression (less than 50 copies/ml) are randomized either to receive IL-2 or not. At study entry, and after 12 months, tissue samples of CSF, lymph node, and genital secretions are obtained, with permission. Patients have physical exams, women of child-bearing potential have pregnancy tests, and blood samples are drawn at clinic visits 12-16 times a year over 3 years so that virologic and immunologic evaluations may be performed. Compensation for time and transportation is given.