Biogen, watch out: Novartis' Tysabri biosim application could portend multiple sclerosis showdown in Europe and US

Regulators on both sides of the Atlantic have agreed to review Novartis’ approval bid for a biosimilar to Biogen’s Tysabri. The potential green light could spell trouble for the multiple sclerosis blockbuster, which has become Biogen’s best-selling drug in the wake of generic competition to its MS pill Tecfidera.