Treatment Simplification in HIV-Infected Patients

Atazanavir is often boosted with ritonavir to raise its levels. However, some patients cannot tolerate ritonavir because of toxicity. Is it safe to drop this agent in patients who have virologic suppression on a ritonavir-boosted atazanavir regimen?

In the industry-supported ARIES study, 515 treatment-naive patients initiated therapy with open-label abacavir/3TC plus ritonavir-boosted atazanavir. At week 36, 419 patients with viral loads <50 copies/mL and no virologic failure were randomized to continue or stop ritonavir. At week 84 (48 weeks after randomization), 86% of patients in the atazanavir group and 81% of those in the boosted-atazanavir group maintained viral loads <50 copies/mL, demonstrating noninferiority of atazanavir to ritonav…