Phase II flop leaves Biogen with thinning pipeline

Biogen (Nasdaq: BIIB) said yesterday it would halt development of Tysabri (natalizumab) as a potential treatment for ischemic stroke, on the back of weak Phase II data.

The East Coast, USA-based biotech firm first gained approval for the monoclonal antibody in 2004, as a treatment for multiple sclerosis. The firm subsequently expanded the label to include Crohn’s disease.

The blockbuster drug, which brought in over $2 billion last year, was not generally believed to have a high chance of success in this indication, and its failure had no noticeable impact on Biogen’s share price.