Nucleotide Reverse Transcriptase Inhibitors

4 Optimal HIV-1 suppression often is difficult to achieve and maintain with currently available antiretroviral drugs, and viral resistance eventually emerges to many drugs. Chronic antiretroviral therapy is also associated with complications such as body fat redistribution, hypertriglyceridemia and hypercholesterolemia, abnormal glucose metabolism, lactic acidosis, pancreatitis, avascular necrosis of bone, and osteoporosis. New drugs are needed to enhance anti-HIV potency, overcome viral resistance, increase tolerability and convenience, and reduce toxicity. A number of antiretroviral drugs are in development, including new nucleotide reverse transcriptase inhibitors (ntRTIs), nucleoside reverse transcriptase inhibitors (nRTIs), nonnucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors, fusion and coreceptor inhibitors, and integrase inhibitors. This selective review will summarize some of the more promising compounds under study.