Clinical implications of reverse transcriptase inhibitor resistance

Abstract

Currently, several drugs are approved by the US Food and Drug Association or available through expanded access programs for the treatment of HIV-1 patients. They target four distinct steps within the HIV-1 replication cycle, i.e., the entry of the virus particle within the target cell (entry inhibitors [EI] subdivided into fusion inhibitors and CCR5 antagonists), the conversion of viral RNA into DNA (nucleoside and non-nucleoside reverse transcriptase inhibitors [NRTI and NNRTI]), the integration of the viral DNA into the host genome (integrase inhibitors [INI]), and the maturation of the virus particle (protease inhibitors [PI]). At the moment, NRTI remain the backbone components for antiretroviral drug combinations that generally comprise 2 NRTI and 1 NNRTI or 2 NRTI and 1 PI (DHHS 2006).