Aim: To assess the safety on the progression of HIV infection and the efficacy on the evolution of metabolic parameters and body fat of either viral load- or CD4 cell-driven strategies of intermittent treatment in chronically HIV-1-infected persons.

Design: Pilot, prospective, open, randomized, controlled 3-year study.

Setting and patients: University hospital. Patients with viral load <200 copies/mL and CD4 cell count >450/mm3 for at least the last 3 months. Three arms with 50 patients each, that will be randomized either to continue antiretroviral therapy, or to discontinue it as long as either HIV-1 RNA be lower than 30000 copies/mL or CD4 cell count be higher than 300/mm3.

Study end-points: evolution of plasma metabolic parameters, body fat, and bone mineral density; incidence of adverse effects due to antiretroviral therapy and symptoms consistent with acute retroviral syndrome; incidence of virological failure (plasma HIV-1 RNA >200 copies/mL while on therapy), immunological failure (CD4 cell count <200/mm3 while on therapy), or clinical failure (development of AIDS-defining illnesses); cost of antiretroviral therapy administered and time free of therapy in the arms assigned to intermittent treatment; and the evolution of T lymphocyte subpopulations and the development of proliferative and cytotoxic responses against HIV.

Inclusion Criteria:

• HIV-infected patients
• On stable antiretroviral therapy
• Viral load below 200 copies/ml
• CD4 above 450 cells/mcl during last 3 months

Exclusion Criteria:

• Weight variation higher than 10% compared with previous stable weight
• Active (CDC-C) opportunistic events
• Major depression or schizophrenia under psychiatric treatment
• Lack of clinical stability
• Pregnant women or planning pregnancy