As Biogen provided an update on a potential sale of its biosimilars business – with the firm “engaged with multiple interested parties” – it also revealed Q2 sales and offered insights into off-patent competition to its Tysabri and Tecfidera brands.

Christopher Viehbacher told his first earnings call as CEO that a review is under way to reverse Biogen’s fortunes, but noted Leqembi will not be a meaningful contributor while treatment and reimbursement bottlenecks remain.

Biogen has conceded that generics to its Tecfidera treatment for relapsing remitting multiple sclerosis may launch “at risk” in the EU, after the US-based player was recently granted further patent protection until 2028.