PTC group: Patients with plasma HIV RNA > 2000 copies/mL before initiation of antiretroviral therapy. Treatment started during the primary infection (as defined by symptoms associated with seroconversion, as confirmed by a first negative ELISA and/or an incomplete P24-positive Western blot) or during the chronic phase of infection, and maintained for at least 12 months in both cases. Control of viral load after antiretroviral treatment interruption: patients must have at least two available viral load assays after stopping antiretroviral therapy. All viral loads must be <400 copies/mL for 12 months or more after stopping antiretroviral therapy, with the possible exception of one blip (one viral load above 400 copies/mL between two viral loads <400 copies/mL at least one month apart from the blip; in this case at least three viral load assays will be required). The last plasma viral load value at the time of inclusion must always be <400 copies/mL