Enfuvirtide [Fuzeon], the first agent in the new class of antiretrovirals called fusion inhibitors, provides durable suppression of HIV and continuous increases in CD4 cells over a 96-week period, and does not appear to be associated with any late-emerging safety issues, according to the latest combined results of the TORO trials presented at the XV International AIDS Conference [Bangkok, Thailand; July 2004]. Over 96 weeks, treatment with enfuvirtide in combination with an optimised background regimen (OB), reduced viral loads to < 400 and < 50 copies/mL in 26% and 17% of patients, respectively. Of those patients randomised to receive enfuvirtide plus OB, 56% remained on treatment at 96 weeks.