Fusion inhibitor

Fusion inhibitors are a class of antiretroviral drugs that are used to prevent HIV from entering human cells. They are part of a broader category of drugs known as entry inhibitors, which also includes CCR5 antagonists and attachment inhibitors.

Mechanism of Action

Fusion inhibitors work by binding to the gp41 protein on the surface of the HIV virus. This prevents the virus from undergoing a structural change that is necessary for it to fuse with the host cell. Without this fusion, the virus is unable to enter the cell and begin the process of viral replication.

Examples

The first fusion inhibitor to be approved by the FDA was Enfuvirtide (brand name Fuzeon) in 2003. Enfuvirtide is a synthetic peptide that mimics a portion of the gp41 protein, allowing it to bind to the virus and prevent fusion.

Another example of a fusion inhibitor is Maraviroc (brand name Selzentry), which is a CCR5 antagonist. Unlike Enfuvirtide, Maraviroc works by binding to the CCR5 receptor on the surface of the host cell, preventing the virus from attaching and entering the cell.

Clinical Use

Fusion inhibitors are typically used in combination with other antiretroviral drugs as part of a HAART regimen. They are often used in patients who have developed resistance to other classes of antiretroviral drugs.

Side Effects

Common side effects of fusion inhibitors include injection site reactions, hypersensitivity reactions, and increased risk of bacterial pneumonia. Less common but more serious side effects can include liver damage and severe allergic reactions.

See Also

• Antiretroviral drug
• HIV
• AIDS
• Enfuvirtide
• Maraviroc