Novo Nordisk's CagriSema (cagrilintide + semaglutide 2.4mg co-formulation) reported topline results from the REDEFINE-2 trial, and they're strong:

"Participants treated with CagriSema achieved a mean body-weight reduction of 22.7% from baseline at 68 weeks, compared to 15.6% with semaglutide 2.4mg alone and 8.2% with cagrilintide alone."
— Novo Nordisk press release, REDEFINE-2 topline results

The mechanism: cagrilintide is a long-acting amylin analog. Amylin is co-secreted with insulin from pancreatic beta cells and acts on the area postrema to reduce appetite and slow gastric emptying — complementary to but mechanistically distinct from GLP-1.

Key takeaways:

• 22.7% weight loss represents a ~7 percentage point improvement over semaglutide alone
• The combination appears to have additive rather than merely overlapping effects
• Safety/tolerability broadly consistent with the individual components
• Novo Nordisk is positioning this as the next-gen Wegovy

The REDEFINE program includes trials in T2D (REDEFINE-1), obesity (REDEFINE-2), and cardiovascular outcomes. This is Novo's answer to tirzepatide and retatrutide.

22.7% is competitive with tirzepatide but notably still below retatrutide's ~24%. Novo needed this to stay in the race. The question is whether the amylin pathway offers any differentiated benefits beyond the weight number.

One area where amylin might shine is glucose regulation in type 1 diabetes. Amylin is virtually absent in T1D patients (since beta cells are destroyed), so cagrilintide could theoretically address an unmet need there. I don't think Novo has announced T1D trials for CagriSema, but the biology supports it.

Also, the fact that CagriSema is a single injection (co-formulated) rather than two separate shots is important for adherence. Nobody wants to inject twice a week for two different drugs.

I'm currently on Wegovy and losing weight steadily (~13% at 6 months). The idea that adding cagrilintide could bump that to 22%+ is very appealing. But I'm worried about the GI side effects — I already have significant nausea on semaglutide alone. Stacking another appetite-suppressing hormone on top sounds like a recipe for misery 😅

Did the REDEFINE data break down the tolerability in detail? Was nausea worse with the combo?

From the available REDEFINE data, the GI tolerability of CagriSema was modestly worse than semaglutide alone but not dramatically so:

• Nausea: ~28% CagriSema vs. ~24% semaglutide alone
• Vomiting: ~12% vs. ~9%
• Diarrhea: ~16% vs. ~14%
• Discontinuation due to AEs: ~7% vs. ~5%

The incremental GI burden from adding cagrilintide appears manageable. Amylin's mechanism of appetite suppression involves area postrema signaling which overlaps with but is not identical to GLP-1 pathways, so there may be some "ceiling effect" on nausea when combining the two.

Importantly, participants on cagrilintide monotherapy had less nausea than those on semaglutide monotherapy, suggesting amylin alone is gentler on the GI tract.

Wait, so this is basically Wegovy + another drug in the same pen? Wouldn't it be super expensive then? Two drugs in one injection has to cost more than just one, right?