The short answer
Combining cagrilintide with semaglutide produced substantial average weight loss in a large trial. The result also came with frequent digestive side effects.
What was studied?
REDEFINE 1 randomly assigned 3,417 adults without diabetes to the combination, either medicine alone, or placebo for 68 weeks. Everyone received lifestyle support. The combination paired 2.4 mg of each medicine.
Percent of starting weight
Original chart based on the study. Values are reported group results.
| Group or measure | Result |
|---|---|
| CagriSema | −20.4% |
| Placebo | −3.0% |
The headline result
Average weight change was −20.4% with the combination versus −3.0% with placebo. This analysis included participants regardless of whether they completed treatment as planned.
Digestive adverse events affected 79.6% with the combination and 39.9% with placebo. They were mainly temporary and mild or moderate, including nausea, vomiting, diarrhea, constipation and abdominal pain. Those percentages describe reported side effects, not treatment discontinuation.
What does it mean?
The study adds evidence about combining two medicines for weight management. Its placebo comparison should not be used to rank CagriSema against tirzepatide or retatrutide from separate trials.
These findings describe a supervised trial regimen, not a recipe for combining medicines independently.
Sources
Garvey and colleagues, New England Journal of Medicine, 2025. Funded by Novo Nordisk. Read the paper.