The limitations of the drugs used against HIV include their toxicity, their tolerability, their propensity to induce resistance when not taken with absolute regularity and their cost. Treatment interruption in patients receiving antiretroviral treatment in the setting of chronic infection is associated with viral rebound and rapid CD4 T cell decrease conducting to antiretroviral therapy restart. In patients with high CD4+ cell counts (patients receiving treatment of chronic infection with controlled viremia and patients who are receiving highly active antiretroviral therapy (HAART) now in whom treatment would not have been started based on current guidelines), the investigators evaluated whether the adjunctional of interferon alfa 2b to 3 structured treatment interruptions correlated with a long time off treatment. HAART was interrupted for 4 weeks, restarted and continued for 12 weeks. After 3 such cycles treatment was indefinitely suspended 48 weeks after study entry. Another aim of this study was to assess the immunological and virological factors associated with the duration of treatment interruption (proviral HIV DNA at baseline and during follow-up, plasma HIV RNA at baseline and during follow-up, CD4 T cell and CD8 T cell HIV specific responses at baseline and after 6 months of interruption).