How Does Fuzeon Work?

Source : http://www.thebody.com/fuzeon/how_work.html

Fuzeon -- A Review of the First Entry Inhibitor

By Calvin Cohen, M.D., M.S.
2003

As mentioned in the last section, HIV inserts a glycoprotein into the CD4 cell wall, and that protein then acts like a zipper to bring HIV directly into contact with the CD4 cell. Fuzeon is like a piece of clothing that gets stuck in the zipper: When Fuzeon attaches to a specific part of the glycoprotein which HIV has inserted into a CD4 cell wall, the glycoprotein can no longer zip itself together, which completely halts the process of HIV fusing with the CD4 cell. Once this process is stopped, as long as Fuzeon remains effective, HIV cannot progress in your body.

That is why entry inhibitors are also known as fusion inhibitors -- they stop the fusion of HIV to a CD4 cell.

Because fusion is completely unrelated to all the other steps in HIV's life cycle that current HIV medications are designed to block, no cross resistance exists between the other classes of HIV medications and Fuzeon. This means that, essentially, everyone with HIV is susceptible to fusion inhibition with Fuzeon. This new class, then, can provide an important "anchor" in a new treatment combination for those who are switching regimens. Therefore, Fuzeon provides a new opportunity to reestablish control of HIV infection.

Fuzeon has several unique features. One is that, unlike all the other HIV medications, Fuzeon must be taken by self-injection. What this means is that to get Fuzeon into your bloodstream, you would be given a small syringe for a simple injection under the skin, similar to how people take insulin. Fuzeon is given as an injection for a similar reason to why insulin is an injection: Fuzeon is a type of molecule that, if taken orally as a pill, will be destroyed in the process of digestion.

Although at first you might feel uncomfortable using a syringe, in most every doctor's office there is someone -- usually a nurse -- who can teach you how to inject this medication by yourself at home.