Good results for Tysabri RMS trial

Irish biotechnology company Elan and USA-based Biogen Idec presented data on a post-hoc analysis of the Phase III AFFIRM trial, that show Tysabri (natalizumab) increases the probability of achieving sustained improvement in physical disability over two years when compared to placebo, in a poster presentation at the World Congress on Treatment and Research in Multiple Sclerosis in Montreal, Canada. The firms claim this is the first evidence that Tysabri is associated with a significant improvement in functional outcome in relapsing multiple sclerosis.

In the trial, Tysabri produced significant results on the cumulative probability of sustained improvement in disability in those treated over two years compared with placebo. In patients with a baseline Expanded Disability Status Scale score more than or equal to 2.0, the probability of achieving sustained improvement was 29.6% with Tysabri compared to 18.7% with placebo (p=0.006). In patients who also had a highly active disease at baseline, the difference between groups was even greater, 35.5% for Tysabri and 15.4% for placebo (p=0.045).