The FDA has approved efavirenz (Sustiva, DuPont Pharmaceuticals, Wilmington, Del) for use in combination with other antiretroviral agents in the treatment of HIV-1 infection. This indication is based on analyses of plasma HIV-RNA levels and CD4 cell counts in controlled studies of up to 24 weeks in duration. At present, there are no results from controlled trials evaluating long-term suppression of HIV-RNA with efavirenz.
Resistant virus emerges rapidly when nonnucleoside reverse-transcriptase inhibitors are administered as monotherapy. The labeling warns, therefore, that efavirenz must not be used as a single agent to treat HIV or added on as a sole agent to a failing regimen. Efavirenz therapy should always be initiated in combination with at least one other new antiretroviral agent to which the patient has not been previously exposed.
Nightingale SL. New Drug to Treat HIV/AIDS Approved. JAMA. 1998;280(17):1472. doi:10.1001/jama.280.17.1472-JFD80010-2-1