Amylin + GLP-1 Combination Phase 3 · Novo Nordisk REDEFINE Phase 3 Data Available

CagriSema

Cagrilintide 2.4mg + Semaglutide 2.4mg · Fixed-Dose Combination · Novo Nordisk

"Novo Nordisk's answer to retatrutide — co-formulated cagrilintide (long-acting amylin analogue) plus semaglutide 2.4mg in a single weekly injection. The REDEFINE Phase 3 programme has completed. Where tirzepatide added GIP to GLP-1, CagriSema adds amylin — a different complementary mechanism with its own additive weight loss data."

Components
Cagrilintide 2.4mg + Semaglutide 2.4mg weekly
Phase 3 (REDEFINE 1)
~22–23% weight loss · 68 weeks
vs Semaglutide alone
~7% additional weight loss vs Wegovy
FDA Status
Phase 3 · NDA submission anticipated
vs Amycretin
Two drugs vs one molecule · same dual mechanism
What It Is

Amylin + GLP-1 — two drugs doing what amycretin does in one

CagriSema is a fixed-dose co-formulation of cagrilintide (a long-acting amylin receptor agonist developed by Novo Nordisk) and semaglutide 2.4mg (the GLP-1 receptor agonist behind Wegovy). Both components are administered as a single weekly subcutaneous injection from a co-formulated pen. The rationale: amylin and GLP-1 work through complementary but distinct mechanisms — together producing greater weight loss than either alone.

Cagrilintide is a modified amylin analogue with fatty acid side chains that extend its half-life to enable weekly dosing — engineered the same way semaglutide was engineered from GLP-1. Amylin is co-secreted with insulin from pancreatic beta cells; it reduces postprandial glucagon, slows gastric emptying through separate pathways from GLP-1, and produces satiety through distinct neural circuits. The combination exploits both pathways simultaneously.

The key comparison: CagriSema does with two co-administered drugs what amycretin aims to do with one molecule. Both combinations target GLP-1 and amylin receptors. CagriSema is more advanced in development (Phase 3 complete); amycretin is cleaner conceptually (single molecule, potentially better pharmacokinetics) but earlier stage.

Phase 1
Safety
✅ Complete
Phase 2
Efficacy
✅ ~15–17% loss
Phase 3
REDEFINE
✅ ~22–23% loss
NDA
Submission
🔄 Anticipated
Mechanism — Why Amylin Adds to GLP-1

Complementary satiety — different circuits, additive effect

How the Two Components Work Together

1
Semaglutide (GLP-1R): Hypothalamic appetite suppression, glucose-dependent insulin secretion, gastric emptying delay via GLP-1R. The proven mechanism behind 15% weight loss in STEP 1. Acts primarily on central neural circuits and pancreatic beta cells.
2
Cagrilintide (amylin/calcitonin receptors): Amylin receptors in the area postrema and nucleus tractus solitarius (brainstem satiety centres) — distinct from hypothalamic GLP-1 receptor circuits. Reduces postprandial glucagon. Delays gastric emptying through vagal pathways separate from GLP-1's mechanism. These non-overlapping neural circuits are why the combination produces additive weight loss.
3
Additive effect in Phase 2: Cagrilintide alone produced approximately 10% weight loss. Semaglutide alone produced approximately 15%. CagriSema produced approximately 17–20% — greater than either alone but not fully additive. The non-full-additivity suggests some pathway overlap or compensation, but the net effect is meaningfully superior to GLP-1 monotherapy.

REDEFINE Phase 3 data: the REDEFINE 1 trial (obesity without diabetes) reported approximately 22–23% weight loss over 68 weeks — placing CagriSema between tirzepatide (~20%) and retatrutide (~28.7%) in efficacy. The comparison to semaglutide 2.4mg (Wegovy) is approximately 7 percentage points of additional weight loss from adding cagrilintide. Whether that additive benefit justifies the additional compound and formulation complexity will be a pricing and access question as much as a clinical one. REDEFINE 2 (T2D) and cardiovascular outcomes data are expected.

Benefits & Evidence

What the data shows

⚖️
Weight loss — 22–23% at 68 weeks
REDEFINE Phase 3: approximately 22–23% weight loss over 68 weeks in adults with obesity. ~7 percentage points greater than semaglutide 2.4mg alone. Additive effect of amylin component confirmed across Phase 2 and 3.
● Strong — Phase 3 RCT data
🩸
Glycaemic control
Phase 2 T2D data shows HbA1c improvements consistent with and beyond semaglutide alone. Phase 3 T2D REDEFINE 2 results pending.
● Moderate — Phase 2 data
Safety

Profile consistent with GLP-1 + amylin class

⚠️
GI adverse events as expected — consistent with GLP-1 plus amylin agonist profile. Both components have established safety profiles from their individual development programmes. The combination does not appear to introduce novel safety signals. Same contraindications as GLP-1 class apply. Not yet approved — do not attempt to source from unregulated markets.
Honest Assessment

Editor's summary

CagriSema is the most advanced GLP-1 + amylin combination in development. Phase 3 data confirms the amylin component adds meaningful weight loss on top of semaglutide. The competition landscape is crowded: retatrutide's 28.7% Phase 3 data sets a high bar, and amycretin aims to deliver the same dual mechanism as CagriSema in a single molecule with potentially superior pharmacokinetics. CagriSema's advantage is its advanced clinical stage — it will likely reach approval before either rival.

The practical positioning: if you're already on semaglutide and not achieving sufficient weight loss, CagriSema offers a path to more. If starting fresh, the choice between CagriSema, tirzepatide, retatrutide, and (eventually) amycretin will be a clinical decision based on efficacy requirements, side effect profile, and cost.

Verdict
"~22–23% Phase 3 weight loss — meaningfully above semaglutide, below retatrutide. The amylin component's additive effect is proven. Phase 3 complete. NDA submission anticipated. The most advanced GLP-1 + amylin combination — competing directly with retatrutide for the next obesity standard of care."