Enfuvirtide: A Novel Agent for the Treatment of HIV-1 Infection

OBJECTIVE: To review the pharmacology, virology, pharmacokinetics, efficacy, safety, and clinical use of enfuvirtide. DATA SOURCES: English-language MEDLINE and AIDSline searches were performed (1966-January 2003) using enfuvirtide, T-20, gp41, and fusion inhibitors as key words. Abstracts from infectious diseases and HIV scientific meetings were identified. DATA EXTRACTION: All publications and meeting abstracts were reviewed and relevant items included. In vitro and preclinical studies were included, as well as Phase II and III clinical trials. DATA SYNTHESIS: Enfuvirtide is a fusion inhibitor used for the treatment of HIV-1 infection. Given its unique mechanism of action, most HIV-1 isolates are susceptible to enfuvirtide. Enfuvirtide is administered by subcutaneous injection twice daily. In clinical trials with antiretroviral-experienced patients, enfuvirtide was effective at suppressing HIV-RNA and increasing CD4+ T-cell counts. Enfuvirtide should be used in combination with other active antiretroviral agents to optimize its efficacy and limit resistance. Injection site reactions associated with administration of the drug are experienced in the majority of patients. Availability of enfuvirtide may be limited by a complex manufacturing procedure. CONCLUSIONS: Enfuvirtide is an effective treatment option for HIV-1-infected individuals when used in combination with other antiretroviral agents. It may be used as part of a regimen for treatment-experienced patients.