(Reuters) – Drugmaker Biogen will buy all outstanding shares of Sage Therapeutics that it doesn’t already own for $7.22 apiece, a filing showed on Friday, sending the latter’s top off 34% in prolonged trade.

As per the filing, Biogen has a ten.2% stake in Sage Therapeutics. The offer price, representing a 30% premium to the stock’s close on Friday, values Sage’s equity at $441.7 million, in keeping with Reuters calculations.

Biogen has been navigating a slow pick-up in sales for its Alzheimer’s drug Leqembi in america after concerns over cost, efficacy and unwanted effects.

Sage, whose shares fell 74.9% last 12 months, abandoned the event of its drug dalzanemdor after multiple trial failures. The corporate said in November that it’ll give attention to its postpartum depression drug, Zurzuvae, which it developed in partnership with Biogen.

In July, Sage also scrapped the event of one other neurological disorder drug it was developing with Biogen.

(Reporting by Puyaan Singh in Bengaluru; Editing by Alan Barona)