Fusion Inhibitor T-20 Found Effective in Phase III Trial; Makers May Seek FDA Approval Later This Year
The experimental fusion inhibitor T-20 has proven effective in its first Phase III large clinical trial, and the manufacturers of the drug say that they plan to seek FDA approval for the medicine this year, the New York Times reports. T-20, which must be injected twice a day, works by blocking HIV from fusing with and entering uninfected cells. It is the "most advanced" of a larger class of antiretrovirals called entry inhibitors, which seek to prevent HIV from entering healthy cells. Antiretrovirals currently on the market can only block HIV from replicating once the virus has entered the cells (Pollack, New York Times, 4/19). T-20 manufacturers Trimeris and Roche announced yesterday that the drug significantly lowered viral levels among 491 patients enrolled in a clinical study. All of the patients had advanced HIV, and most had developed resistance to other antiretrovirals. Two-thirds of the participants were given T-20 in conjunction with other antiretrovirals, and the rest of the patients received a traditional antiretroviral regimen (Wall Street Journal, 4/19). Participants who received T-20 experienced a 98% reduction in blood viral levels after 24 weeks, while those who did not receive the drug experienced an 80% reduction in viral levels, Trimeris CEO Dr. Dani Bolognesi said. The companies did not release "detailed trial results," stating that additional data would be presented at a medical conference in the future (New York Times, 4/19).
Potential for the Future
Trimeris and Roche plan to apply for FDA approval for T-20 in the second half of this year, and because the drug has received "fast track" status from the FDA, it could be approved and on the market by early 2003 (Reuters, 4/18). Experts said that T-20 will mainly be used to help patients who have developed resistance to other antiretrovirals. "It provides an option for people who are failing therapy," Dr. Douglas Richman of the University of California-San Diego said (New York Times, 4/19). Andrew Pendrill, a pharmaceutical analyst at ABN AMRO in London, said that the rising number of patients experiencing drug resistance will give T-20 "considerable market potential." Roche estimated that annual sales of T-20 and another fusion inhibitor known as T-1249 could reach $303.7 million to $607.5 million (Reuters, 4/18). However, experts say that the drug's injectable form could limit the number of patients who use it (New York Times, 4/19).