The duration of the treatment by FUZEON® is 6 months in association with a combination of two or more antiretroviral molecules which will be pursued during the next 6 months. These molecules will be chosen according to the past treatment of the patients. A combination including efavirenz, lopinavir/ritonavir, and tenofovir/emtricitabine (under the shape of TRUVADA®) will be proposed to the naïve patients. For the pretreated patient(approximately a quarter of the inclusions), antiretroviral therapy will be chosen in every case on the basis of the therapeutic history and of the viral genotypes of resistance. Such association will contain at least two antiretroviral molecules, issued from two different families among the three following ones (nucleoside inhibitors of the reverse transcriptase, non-nucleoside inhibitors of the reverse transcriptase, protease inhibitors).