Getting the most from available antiretroviral therapies.

Two decades after the approval of the first antiretroviral drugs, combination HAART has dramatically lowered the risk of illness and death for people with HIV. The year 2007 was another milestone, witnessing the approval of the first agents in two new anti-HIV drug classes--CCR5 antagonists and integrase inhibitors--that provide new options for treatment-experienced patients. Today, however, the anti-HIV drug pipeline is relatively sparse, with no blockbusters in the foreseeable future. While the first HIV maturation inhibitor, bevirimat, continues to slowly make its way through clinical trials, another once-promising agent that works by a completely novel mechanism, Koronis Pharmaceuticals' KP-1461, was recently put on hold after laboratory tests indicated that it did not demonstrate the expected antiviral activity.