Study of Protease Inhibitor Regimen Switch in HIV-1 Infected Patients With Undetectable Viral Load to Prove the Non-inferiority of Once Daily Dose Regimen Versus the Current Twice Daily Regimen to Maintain the Viral Load Under the Limit of Detection.

Inclusion Criteria:

• HIV-1 infected patients

• Treatment with an association of 3 molecules including two Nucleotidic ReverseTrasncriptase Inhibitors and a ritonavir-boosted protease inhibitor BID, unchanged forat least one month

• At least two documented undetectable viral loads (under 50 copies/ml) within the last 3 months

• Naiive from darunavir

• Free from any opportunistic infection

• Creatinin < 3N

• ASAT & ALAT < 5N

• Haemoglobin > 7 g/dl

• Platelets > 50 000/mm3

• Negative pregnancy test for women of childbearing potential and use of a mechaniccontraceptive during sexual relationships

• Signed informed consent

Exclusion Criteria:

• HIV-2 infected patients

• Treatment different from the association described in the inclusion criteria (2 NRTIs

• 1 PI/r BID)

• Patients with a documented problem of treatment compliance within the last 12 months

• Ongoing active treatment against any opportunistic infection or tuberculosis

• Any critic concomitant condition (alcohol consumption, fatigue) that may jeopardizetreatment compliance and/olr tolerance, and interfere with the protocol compliance

• Any concomitant treatment that may potentialize or inhibit hepatic cyotchrome-basedenzymes

• Patient already treated with darunavir

• Patient treated with tipranavir, enfuvirtide, raltegravir, etravirine, and/ormaraviroc