Lilly/Daiichi Sankyo's prasugrel cuts CV AEs 19% vs Plavix, but side effects raise doubts

US drug major Eli Lilly reported positive findings from a late-stage trial of its antiplatelet drug prasugrel, showing that it works better than Sanofi-Aventis' blockbuster Plavix (clopidogrel), although its bleeding side effects are significantly worse.

In the pivotal Phase III head-to-head TRITON TIMI-38 trial, the investigational anticlotting drug produced a highly significant 19% reduction in relative risk (p=0.0004) for the composite endpoint of cardiovascular death, non-fatal heart attack or non-fatal stroke when compared with Plavix in the treatment of patients across the full spectrum of acute coronary syndrome undergoing percutaneous coronary intervention.

Some observers believe that prasugrel, which was originated by Japanese drugmaker Daiichi Sankyo, could one day rival Plavix, the world's fourth highest-selling drug in the 12 months to August 2007 (Marketletter October 22), earning almost $6.0 billion in global sales last year. "Our study provides compelling evidence that the prasugrel regimen tested is superior to standard-dose clopidogrel as an antiplatelet therapy to support patients undergoing coronary stenting," said lead investigator Elliott Antman.