Emerging resistance profiles of newly approved antiretroviral drugs.

The antiretroviral treatment goal in highly treatment-experienced patients is now suppression of viral replication to undetectable levels, a goal that can be achieved by strategic use of combinations that include newer antiretroviral drugs. Newer drugs in established classes that improve virologic response when added to optimized background therapy include the protease inhibitors darunavir and tipranavir and the second-generation nonnucleoside analogue reverse transcriptase inhibitor etravirine. New drugs from new classes that have proved active in treatment-experienced patients include the chemokine coreceptor 5 (CCR5) antagonist maraviroc and the integrase strand-transfer inhibitor raltegravir. Knowledge of the resistance patterns and predictors of response with these new agents and careful selection of background therapy are crucial to maximizing virologic response and preventing emergence of resistance. This article summarizes a presentation on emerging resistance profiles of newer antiretroviral drugs made by Eric S. Daar, MD, at an International AIDS Society-USA Continuing Medical Education course in Los Angeles in March 2008. The original presentation is available as a Webcast at www.iasusa.org.