Utilizing a new class of antiretrovirals: role of fusion inhibitors in HIV disease management.

HIV-infected patients who stand to benefit most from the availability of new antiretrovirals are those who have the fewest treatment options. Clinical trials have shown that in antiretroviral-experienced patients requiring a regimen change, including an antiretroviral drug from a previously unused class, is associated with greater treatment response. In clinical trials of the entry inhibitor enfuvirtide, triple-class-experienced patients treated with enfuvirtide plus an optimized background regimen of 3 to 5 active antiretrovirals consistently showed virologic and immunologic responses superior to those of the patients who received optimized background treatment alone, regardless of the number of active antiretroviral drugs included in the optimized background treatment. Adverse events have not been observed to be considerably greater among enfuvirtide-treated patients than among those receiving optimized background treatment alone. Injection site reactions of mostly mild to moderate severity were the most common adverse events in the enfuvirtide group, with few resulting in discontinuation.