US-based pharmaceutical groups Biogen and AbbVie yesterday issued a press release announcing the market withdrawal of the multiple sclerosis treatment Zinbryta, as many patients have reported encephalitis after taking the drug. Simultaneously, EMA yesterday announced it had started reviewing the latest cases in Germany and Spain. Experts estimate that there are 2.5 million people suffering from multiple sclerosis in the world, approximately 8,000 of which were treated with Zinbryta (2016). Zinbryta had already been reported as a potential cause of serious liver damage, therefore FDA had imposed to prescribe it only if the patient did not respond to other treatments. AbbVie and Biogen have entered into an agreement to jointly market the drug in the US, Canada and Europe. It generated $107 m in 2017. Biogen also has another multiple sclerosis drug, Avonex, which delivered over $2.15bn in 2017.