Novo Nordisk’s IL-6 inhibitor ziltivekimab failed in a cardiovascular Phase 3 trial, sending shares down more than 9%. In the ZEUS study, the drug did not reduce the risk of major adverse cardiovascular events in patients with atherosclerotic cardiovascular disease, chronic kidney disease, and inflammation. Novo had framed the program as “high risk/high reward,” aiming to translate reductions in inflammatory biomarkers into clinical risk reduction. While a prior mid-stage study showed meaningful C-reactive protein reduction, ZEUS did not deliver corresponding event benefits. Novo CSO Martin Holst Lange said the result does not change the company’s cardiovascular research commitment, while acknowledging the setback for the hoped-for MACE advantage. The company expects additional readouts in related programs—HERMES in heart failure and ARTEMIS in acute heart attack—early next year. The ZEUS outcome narrows IL-6-targeting confidence in a crowded cardiometabolic landscape where differentiation remains difficult as GLP-1 franchise competition intensifies.