The purpose of this study is to determine if patients who have achieved virologic suppression (< 400 copies/mL) on any dual PI combination, can substitute both PIs with the single boosted PI darunavir given 600/100 rtv bid and maintain comparable virologic suppression (% < 50 c/mL) for 24 weeks. Randomized, non-blinded, multicenter, 48 week, controlled trial to assess the non-inferiority of substituting DRV/r for a dual boosted PI combination in patients with stable virologic suppression on a regimen containing a dual boosted PI combination plus at least one additional FDA-licensed antiretroviral agent from another class. Participants will be randomized (1:1) to one of the included treatment arms.