Atazanavir (BMS-232632) is an orally available, azapeptide human immunodeficiency virus type 1 (HIV-1) protease inhibitor with EC50 of 2.6-5.3 nM, and EC90 of 9-15 nM. [1] Atazanavir has been shown to be effective in HIV-1 strains resistant to other antivirals such as nelfinavir, saquinavir, and amprenavir. Additionally, indinavir- and ritonavir-resistant strains are more six- to nine-fold more sensitive to atazanavir.

Atazanavir's is highly selective for HIV-1 protease and only exhibits cytotoxic effects in 6500- to 23000-fold higher concentrations than is required for anti-HIV activity. Atazanavir has been shown to be additive or synergistic with a number of different antiviral therapies without antagonistic anti-HIV activity or cytotoxicity. [2, 3]