The trial enrolled 6,376 adults at 757 sites in 38 countries, who received once-monthly ziltivekimab 15 mg or placebo on top of usual care for a median of 29.1 months. The primary endpoint occurred in 561 patients on ziltivekimab and 565 on placebo. Novo reported a hazard ratio of 0.99 (95% CI 0.88–1.11) when it announced headline results on July 31.

Ziltivekimab hit its biological target, lowering hs-CRP by 64% and free IL-6 by 76% compared with placebo. Overall side effect rates were similar, but serious infections were more common with ziltivekimab (20.4% vs 17.9%). Participants were at very high risk: 92% had high blood pressure, nearly two-thirds had type 2 diabetes and 42% had heart failure.

Novo’s remaining cardiovascular outcomes trial of ziltivekimab, ARTEMIS after an acute heart attack, is continuing.

“While the lack of clinical benefit in ZEUS is disappointing, we already know from prior research that targeting inflammation can significantly reduce cardiovascular risk, so it’s important not to overinterpret these findings,” says Paul M. Ridker, lead author, Harvard Medical School and Mass General Brigham.

Sources: American Heart Association news release, 7 November 2026 — read the release · NEJM publication (doi: 10.1056/NEJMoa2612126) · Novo company announcement No 45/2026, 31 July