Journal of AIDS & Clinical Research

An Update on HIV-1 Protease Inhibitor Resistance

Abstract

John D Baxter, William M Chasanov and Jessica L Adams

Protease inhibitors (PIs) are a potent class of antiretroviral agents which have been used to successfully treat many patients with HIV disease. As with other classes of antiretroviral agents, drug resistance has been described with each of the PIs. PI resistance can occur in newly infected individuals due to transmission of drug resistant strains or, more commonly, evolves from the selective pressure of antiretroviral therapy. When present, PI resistance results in an increased likelihood of drug failure. Individual protease gene mutations have been identified which are associated with phenotypic resistance to these agents. However, protease mutations can exert different effects on individual PIs, as some will produce resistance to one agent and may enhance susceptibility to another. In patients failing PIs, particularly in the setting of prior treatment with multiple agents, protease resistance patterns may be complex and result in broad cross-resistance to the class. Strategies to limit the development of resistance to these agents and manage its occurrence are important for the on-going care of individuals with HIV infection.