Cagrilintide vs Retatrutide
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
Cagrilintide
Cagrilintide is a long-acting amylin analog in development, showing promising results when combined with semaglutide (CagriSema). Amylin is a hormone co-secreted with insulin that promotes satiety.
Full details →Retatrutide
Retatrutide (LY3437943) is a first-in-class triple agonist peptide targeting GIP, GLP-1, and glucagon receptors simultaneously. Developed by Eli Lilly, it is currently in Phase 3 clinical trials and has demonstrated the highest weight loss of any obesity medication to date — up to 28.7% body weight reduction at 48 weeks. The triple-receptor mechanism represents the next evolution beyond dual agonists like tirzepatide.
Full details →Side-by-Side Comparison
| Aspect | Cagrilintide | Retatrutide |
|---|---|---|
| Dose Range | 300 mcg–4.5 mg | 4 mg–12 mg |
| Frequency | Less than daily | Less than daily |
| Cycle Length | 26–68 weeks | — |
| Route | subcutaneous | subcutaneous |
| Mechanism | Activates amylin receptors (calcitonin receptor with RAMP proteins) to slow gastric emptying, suppress glucagon secretion, and reduce food intake through central satiety mechanisms distinct from GLP-1. | Retatrutide is a synthetic peptide that activates three incretin/metabolic hormone receptors: (1) GLP-1 receptor — appetite suppression, insulin secretion, delayed gastric emptying, (2) GIP receptor — enhanced insulin sensitivity, improved fat metabolism, (3) Glucagon receptor — increased energy expenditure, hepatic fat mobilization, thermogenesis. The glucagon receptor component is the key differentiator, adding an energy-expenditure mechanism absent from GLP-1 and dual GIP/GLP-1 agonists. The molecule uses a C20 fatty diacid for albumin binding, enabling once-weekly dosing. |
| Typical Dosage | Clinical trials: 2.4mg weekly as monotherapy or in combination with semaglutide 2.4mg (CagriSema). Optimal dosing still being determined. | Phase 2 trial doses: 0.5 mg, 4 mg, 8 mg, and 12 mg weekly. The 12 mg dose produced maximum weight loss (28.7%). Phase 3 trials are evaluating doses up to 12 mg. Dose escalation schedule similar to other GLP-1s (start low, increase every 4 weeks). Final approved dosing not yet established — Phase 3 trials ongoing. |
| Administration | Subcutaneous injection once weekly. Currently only available in clinical trials - not yet FDA approved. | Subcutaneous injection, once weekly. Phase 3 trials use pre-filled single-dose pens. Not yet commercially available — estimated FDA approval ~2027-2028. |
| Side Effects | Nausea, vomiting, diarrhea, constipation similar to other incretin-based therapies. Combination with semaglutide may increase GI effects initially. | Phase 2 data: nausea (up to 25%), diarrhea (up to 22%), vomiting (up to 15%), constipation, decreased appetite. GI side effects were dose-dependent and generally mild-to-moderate. Lower rates of nausea compared to semaglutide, potentially due to GIP component. Increased heart rate observed at higher doses. |
| Best For |
Key Differences
Unique to Cagrilintide:
Unique to Retatrutide:
Key Studies
Cagrilintide
- Efficacy and safety of co-administered cagrilintide and semaglutide versus semaglutide alone in adults with overweight or obesity with or without type 2 diabetes in Japan and Taiwan (REDEFINE 5): a multicentre, randomised, active-controlled, phase 3a trial.
The lancet. Diabetes & endocrinology, 2026
- A cross-species atlas of the dorsal vagal complex reveals neural mediators of the effects of cagrilintide on energy balance.
Nature metabolism, 2026
- Cagrilintide-Semaglutide in Adults with Overweight or Obesity and Type 2 Diabetes.
The New England journal of medicine, 2025
Retatrutide
- Retatrutide in type 2 diabetes mellitus and obesity: an overview.
Expert review of clinical pharmacology, 2026
- Retatrutide for the treatment of obesity, obstructive sleep apnea and knee osteoarthritis: Rationale and design of the TRIUMPH registrational clinical trials.
Diabetes, obesity & metabolism, 2026
- Rationale, design and baseline characteristics of the TRANSCEND-CKD trial of retatrutide in patients with chronic kidney disease.
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, 2026
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