US FDA has granted traditional approval to Fuzeon (enfuvirtide), the first and only fusion inhibitor for the treatment of HIV, Roche and Trimeris Inc announced here.

The FDA granted accelerated approval to Fuzeon, co-developed by Roche and Trimeris, on the basis of 24-week data in March 2003. Accelerated approval is a special regulatory status designed to expedite the approval of therapies for serious or life-threatening illnesses which provide meaningful benefit to patients over existing treatments. The traditional approval of Fuzeon was based on results from phase III clinical trials over 48 weeks which confirmed the durable efficacy and safety of Fuzeon-based regimens, according to a release from Trimeris.

"The 48-week data confirm that enfuvirtide-based regimens substantially improve virologic and immunologic outcomes in treatment experienced patients after approximately one year of therapy. Forty-six per cent of patients on enfuvirtide-based regimens achieved a significant reduction in HIV levels, compared to 18 per cent of patients taking previous standard of care regimens. These strong results establish enfuvirtide as an invaluable component of therapy for triple-class experienced patients who require a change in regimen," said Joel Gallant, associate professor of Medicine and Epidemiology, Division of Infectious Diseases, The Johns Hopkins University School of Medicine, Baltimore, Maryland.

Steven D. Skolsky, CEO, Trimeris noted, "Together with our partner Roche, Trimeris is proud to reach this important milestone for Fuzeon. The significance of this milestone is further reinforced by data recently presented at the XV International AIDS Conference (IAC), which show that Fuzeon is not only potent, but durable over 96 weeks."

Fuzeon in combination with other antiretroviral agents is indicated for the treatment of HIV-1 infection in treatment-experienced patients with evidence of HIV-1 replication despite ongoing antiretroviral therapy. There are no studies of Fuzeon in antiretroviral naïve patients.

Fuzeon, co-developed by Roche and Trimeris is also approved in the European Union, Switzerland and Canada. Unlike other HIV drugs that work after HIV has entered the human immune cell, Fuzeon works outside the CD4 cell, blocking HIV from entering the cell. For this reason, Fuzeon is effective in treatment-experienced patients who have developed resistance to other anti-HIV drugs, though patients may still develop resistance to Fuzeon, the company claims in the release.