02:24 PM EDT, 07/31/2026 (MT Newswires) -- Novo Nordisk ( NVO ) shares tumbled Friday after the Danish pharmaceutical giant said a late-stage trial of ziltivekimab was unable to reduce major adverse cardiovascular events, compared with a placebo.

Ziltivekimab is an experimental monoclonal antibody meant to reduce cardiovascular inflammation and improve cardiovascular results. The phase 3 ZEUS trial evaluated a once-monthly 15-milligram dose of ziltivekimab versus placebo in more than 6,300 high-risk patients for reducing the risk of major adverse cardiovascular events, or MACE, defined as cardiovascular death, non-fatal heart attack or non-fatal stroke.

"While ziltivekimab demonstrated target engagement and inhibition of the IL-6 pathway, as reflected by expected reductions in free IL-6 and high-sensitivity c-reactive protein respectively, this did not translate into MACE risk reduction versus placebo in people with atherosclerotic cardiovascular disease, chronic kidney disease and inflammation," Novo said in a statement Friday.

The company's American depositary receipts slumped 9.2% in afternoon trade.

Despite the trial outcome, Novo said two ongoing cardiovascular outcomes studies evaluating ziltivekimab in patients with heart failure and those following an acute heart attack would continue, with results expected in the first half of 2027.

The ZEUS result will not affect the company's 2026 adjusted operating profit guidance, but will result in a noncash impairment charge in the third quarter, the company said. Full trial results will be presented at a scientific meeting later this year.

Novo is scheduled to report its latest financial results next week.

Earlier this month, the company sued rival Eli Lilly (LLY) in the US over alleged "misleading" advertising campaigns for its obesity and diabetes drugs that compete with the Danish pharmaceutical giant's products.

The ZEUS trial has "significant relevance" to Monte Rosa Therapeutics' ( GLUE ) MRT-8102 program, which is being assessed in an expanded phase 1 study in elevated cardiovascular disease risk subjects, Wedbush Securities said.

"As we await further insight into ZEUS data, as well as data from (two other) studies, to be conservative, we are removing credit for MRT-8102 from our valuation with clinical de-risking for the program likely delayed significantly," the brokerage said in a note to clients.

Wedbush reduced its price target on the Monte Rosa stock to $27 from $37 while maintaining its outperform rating.

Monte Rosa shares plummeted 29% intraday Friday.

Price: 47.28, Change: -4.34, Percent Change: -8.40