Enfuvirtide (INN) is an HIV fusion inhibitor, the first of a class of antiretroviral drugs used in combination therapy for the treatment of HIV-1 infection. It is marketed under the trade name Fuzeon (Roche).

Pharmacokinetics

Mechanism of action

Enfuvirtide works by disrupting the HIV-1 molecular machinery at the final stage of fusion with the target cell, preventing uninfected cells from becoming infected. A biomimetic peptide, enfuvirtide was designed to mimic components of the HIV-1 fusion machinery and displace them, preventing normal fusion. Drugs that disrupt fusion of virus and target cell are termed entry inhibitors or fusion inhibitors.

HIV binds to the host CD4+ cell receptor via the viral protein gp120; gp41, a viral transmembrane protein, then undergoes a conformational change that assists in the fusion of the viral membrane to the host cell membrane. Enfuvirtide binds to gp41 preventing the creation of an entry pore for the capsid of the virus, keeping it out of the cell.

Enfuvirtide is also an activator of the chemotactic factor receptor, formyl peptide receptor 1, and thereby activates phagocytes and presumably other cells bearing this receptor.The physiological significance of this activation is unknown.

Microbiology

Enfuvirtide is considered to be active against HIV-1 only. Low activity against HIV-2 isolates has been demonstrated in vitro.

Variable susceptibility to enfuvirtide has been observed in clinical isolates, with acquired resistance the result of a mutated 10 amino acid motif in viral gp41. Primary resistance, however, has yet to be observed.

Uses

Enfuvirtide is an antiretroviral medicine. It is used for human immunodeficiency virus (HIV) infection. It slows the progress of HIV infection, but it is not a cure. HIV destroys cells in the body, called CD4 T cells. These cells are a type of white blood cell and are important because they are involved in protecting your body from infection. 

Enfuvirtide side effects

Get emergency medical help if you have signs of an allergic reaction: skin rash or hives; fever with vomiting; blood in your urine; difficulty breathing; fainting; swelling of your feet, face, lips, tongue, or throat.