T-20 (FUZEON) Gets Priority Review

On October 11 Roche and Trimeris, Inc. announced that the FDA had granted priority review to FUZEON (TM) (generic name enfuvirtide, formerly known as T-20). This means that the FDA plans to review the application for approval in six months, and announce the results by March 16, 2003 (six months after the application for approval was submitted).

Enfuvirtide works differently from any currently approved HIV drugs: it blocks a step in the process by which HIV fuses with a cell membrane and enters the cell. Since it has an entirely different mechanism of action, virus that has become resistant to approved drugs will not automatically be resistant to this one. However, resistance to enfuvirtide does develop, as with other antiretrovirals. This drug also must only be used in combination treatments, never alone.

Enfuvirtide must be injected twice a day, can be difficult to use, and is difficult to manufacture so it will probably be expensive. For these reasons it will likely be used mainly by patients who do not have other good options.