Sanofi-Aventis announces ‘encouraging’ idraparinux results despite termination

Sanofi-Aventis has this week presented the results of the Amadeus trial, with the firm reporting encouraging results for idraparinux as a preventative treatment for stroke and non-central nervous system systemic embolic events in atrial fibrillation patients.

These results were announced at the annual congress of the International Society on Thrombosis and Haemostasis in Geneva, with the compound shown to be as effective as vitamin K antagonist (VKA) warafin in the trial.

However, clinically relevant bleeding – a primary safety outcome in the trial – was found to be significantly higher in patients receiving iradparinux compared to those administered with warafin, though no net difference was seen in all-causes mortality in both patient groups.

As a result of this difference in bleeding events with low event rates, the trial was terminated ahead of schedule by the firm

Professor Harry Buller, of the Academic Medical Centre Department of Vascular Medicine at the University of Amsterdam, said: “With once-a-week idraparinux treatment we could have a convenient alternative to the cumbersome VKA treatment for patients suffering from atrial fibrillation recurrent complications.”

He added that the new Borealis-AF study involving once-weekly administration with reversible biotinylated idraparinux should address issues relating to the safety and dose adjustment of the drug.

In December 2006, Sanofi-Aventis reported that once-weekly administration of idraparinux could offer patients with good acceptability “a new paradigm” in reducing the risk of thromboemolism.