Novo-Nordisk A/S shares plunged as much as 10% after the company announced that a late-stage clinical trial for a heart disease drug failed to reduce major cardiovascular events more effectively than a placebo. In a statement released on Friday, the Danish pharmaceutical giant reported that while its experimental drug, ziltivekimab, demonstrated some biological activity, it did not achieve a statistically meaningful reduction in MACE (major adverse cardiovascular events)—defined as cardiovascular death, non-fatal heart attack, or non-fatal stroke—among patients with specific conditions.

"Although ziltivekimab did not deliver the MACE benefit we had hoped for, this does not alter our strategic commitment to cardiovascular disease," said Chief Scientific Officer Martin Holst Lange. The company's shares listed in Copenhagen were last quoted down 8.6%, while its American Depositary Receipts (ADRs) fell 9.8% in pre-market trading.