Can you tell me what a fusion inhibitor exactly is and decribe how it works in the body?

Fusion inhibitors are a subclass of drugs called entry inhibitors. Unlike previous HIV medications that target HIV once it attacks and infects a T-cell, entry inhibitors prevent HIV from being able to attach to a T-cell. By keeping HIV from attaching to the T-cell, the T cell survives and we've prevented HIV from reproducing within the T cell. Fuzeon is one type of entry inhibitor and is considered a fusion inhibitor.

One of the most advanced of the entry inhibitors in clinical trials is Pfizer's UK-427,857 (maraviroc) a CCR5 co-receptor antagonist, which inhibits the interaction of HIV with the most commonly used chemokine co-receptor. Maraviroc is an oral tablet.

GSK also has a CCR5 inhibitor named Aplaviroc. It recently halted trials in treatment naive patients due to liver toxicity. Trials are still ongoing with treatment experienced patients.

For detailed info on how Fuzeon works, check out the video on the web: Fuzeon Video

There's a lot of information on the web about all of the other entry inhibitors being investigated. Go to your favorite search engine and search for "HIV Entry Inhbitors."

Also check out the variety of entry inhibitor resources on thebody.com.

--dk