Study Evaluating the Efficacy of a Reduced Dose Atazanavir in HIV-1-infected Patients

"1. In patients signed an informed consent and meeting all the eligibility criteria at the time of the run-in (S-4),~2. switch of antiretroviral therapy Atazanavir 300 mg/ritonavir 100 mg once a day to Atazanavir 200 mg/ritonavir 100 mg once a day without changing the combination of 2 NRTIs associated.~The administration will be done once a day orally for 48 weeks.~The usual recommended dose of atazanavir is 300 mg once daily with 100 mg of ritonavir once daily with food. Ritonavir acts by potentiating the pharmacokinetics of atazanavir."