Fuzeon

Fuzeon is the brand name for enfuvirtide, a fusion inhibitor antiretroviral medication used to treat HIV-1 infection. It is typically prescribed for people who have experienced extensive antiretroviral resistance and may be used in combination with other antiretroviral drugs when viral replication persists despite ongoing therapy. It is approved for adults and for pediatric patients aged 6 years and older.

Enfuvirtide works by binding to the gp41 subunit of the HIV envelope and preventing the conformational changes required for viral and cellular membrane fusion. By blocking entry of the virus into host cells, it inhibits HIV-1 replication. It is a 36-amino-acid peptide derived from gp41.

Administration and dosing are by subcutaneous injection. The standard dose is 90 mg injected twice daily. Patients or caregivers typically reconstitute and dilute the drug for injection and should rotate injection sites to minimize local reactions. The drug is stored refrigerated (2-8°C) and may be kept at room temperature for a limited time after reconstitution.

Common adverse effects include injection-site reactions such as pain, erythema, and nodules, which occur in most patients. Other potential effects include fever, nausea, and fatigue. More serious concerns include an increased risk of bacterial pneumonia, particularly in those with advanced HIV infection, and hypersensitivity reactions. As with all antiretrovirals, enfuvirtide is used as part of combination therapy to reduce the likelihood of resistance, and adherence to the full regimen is important. Interactions with other drugs are limited, but treatment plans should consider the overall antiretroviral regimen.