Shares in Novo Nordisk fell as much as 6% on Friday before recovering some ground later in the session, extending recent losses that threaten to wipe out all the gains since the drugmaker launched its blockbuster weight-loss treatment Wegovy four years ago.

Novo Nordisk’s shock profit downgrade and 22% share price plunge spooked global markets. But for ResMed shareholders, the story could have a silver lining — with sentiment finally shifting back toward a more balanced view of sleep apnoea treatment.