Metabolic peptides differ by how many receptor pathways they engage. In broad terms, triple agonism (Retatrutide) engages more pathways than dual agonism (Tirzepatide), which engages more than single agonism (Semaglutide). Amylin analogs (Cagrilintide) hit a separate appetite pathway (the CALCR/RAMP amylin receptor complex) and are often studied in combination with a GLP-1 for additive rather than competing effects — the basis of CagriSema.
| Compound | Mechanism | Reported trial figure |
|---|---|---|
| Retatrutide | GLP-1 / GIP / glucagon (triple) | ~24–29% mean weight reduction (TRIUMPH program; Phase 3 ongoing) |
| Tirzepatide | GLP-1 / GIP (dual) | 22.5% at 72 weeks (SURMOUNT-1, 15 mg) |
| CagriSema | Amylin + GLP-1 | ~20% (REDEFINE 1) |
| Semaglutide | GLP-1 (single) | ~15% (STEP program) |
| Cagrilintide | Amylin analog | Studied standalone and in combination |
These figures come from published clinical research and are provided for scientific context only; the research chemicals sold by vendors are for laboratory use, not human consumption.
Higher-potency compounds (Retatrutide, Tirzepatide) command higher prices per milligram, but the gap narrows sharply once you compare after discount codes. That is exactly what PepsTracker is built to surface. Rather than reading a "best" list, compare the actual live price of the compound you want:
All of these compounds are tracked on the PepsTracker homepage, normalized to cost-per-milligram with every discount code applied. Vendors like Platinum Peptides carry the full metabolic range — including their coded GLP-1/GIP products and a Sema/Cagri blend — with 15% off via code pepstracker15. Pick your compound and the cheapest verified source is at the top.
In published research, Retatrutide (a triple GLP-1/GIP/glucagon agonist) has reported the largest mean weight-reduction figures in its Phase 3 TRIUMPH program, ahead of Tirzepatide and Semaglutide. It remains investigational.
CagriSema is a combination of Cagrilintide (an amylin analog) and Semaglutide (a GLP-1 agonist). The pairing engages two different appetite pathways and reported roughly 20% weight reduction in the REDEFINE 1 trial.
PepsTracker compares Semaglutide, Tirzepatide, Retatrutide, Cagrilintide and blends across 26 vendors by cost-per-milligram with discount codes applied, updated daily.