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 |
|---|---|---|
| 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. |
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Key Differences
Unique to Cagrilintide:
Unique to Retatrutide:
Detailed Analysis
Commonalities
Both Cagrilintide and Retatrutide are commonly used for Fat Loss.
Which Should You Choose?
Both peptides have similar evidence levels for their shared goals. Your choice may depend on specific use case, availability, or personal response.
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