Semaglutide vs Retatrutide
Semaglutide targets one receptor; retatrutide targets three, adding GIP and glucagon receptor agonism. Retatrutide’s data are from phase 2; semaglutide’s from a completed phase 3 programme.
Semaglutide
A long-acting GLP-1 receptor agonist, the reference molecule of the modern incretin era in both injectable and oral form.
BEST STUDIED FOR
Incretin & metabolic
Read the cited profile →
Retatrutide
Retatrutide (LY3437943) is a single peptide engineered to activate three receptors at once — GLP-1, GIP and glucagon.
BEST STUDIED FOR
Triple-agonist (GLP-1/GIP/glucagon) metabolic research
FREE GIFTFree GHK-Cu 50 mg with every Retatrutide 30mg vial and free GHK-Cu 100 mg with every Retatrutide 60mg vial, until 15 Oct — one per vial, added automatically at checkout.
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Price, purity and dispatch
| Compare | Semaglutide | Retatrutide30 mg · more sizes |
|---|---|---|
| Price | — | fromR1,749 |
| Cost per mg | — | R58.3 / mg |
| Purity (Janoshik) | — | 99.676%HPLC, published |
| Stock | — | Restocking |
| Dispatch | — | When restocked |
| Certificate | — | View CoA → |
| Literature | — | 3 papers → |
| Research focus | Incretin & metabolic | Triple-agonist (GLP-1/GIP/glucagon) metabolic research |
| Read the cited profile | Notify me |
Prices are read live from the catalogue. Cost per mg is the vial price over its stated mg. Purity is shown only where the certificate is published. Every compound is supplied for laboratory research only.
SIDE BY SIDE
| Semaglutide | Retatrutide | |
|---|---|---|
| The key difference | GLP-1 only | GLP-1 + GIP + glucagon |
| Class | Incretin & metabolic | Incretin & metabolic |
| Mechanism | Semaglutide is a GLP-1 analogue with amino-acid substitutions and a C18 fatty-diacid chain that binds albumin, extending its half-life to about a week. | Retatrutide (LY3437943) is a single peptide engineered to activate three receptors at once — GLP-1, GIP and glucagon. |
| Status | Approved medicine (type 2 diabetes and chronic weight management) in many countries, with a large phase 3 programme (STEP, SUSTAIN, SELECT). Prescription-only in South Africa. | Investigational triple agonist in phase 3 trials; not an approved medicine. |
| Reported safety signals | Reviews document gastrointestinal effects as the most common; pancreatitis, gallbladder events and the effect on lean mass are active topics. Trials show weight regain after stopping. | Phase 2 trials reported mainly gastrointestinal adverse events and dose-related heart-rate increases. |
| A key study | Reviews the safety profile of semaglutide across subcutaneous and oral formulations. (Front Endocrinol (Lausanne) 2021, PMID 34305810) | In a phase-2 randomised trial, participants receiving retatrutide showed dose-dependent reductions in body weight over 48 weeks. (N Engl J Med 2023, PMID 37366315) |
WHEN TO RESEARCH WHICH
Semaglutide offers the mature evidence base; retatrutide is the research frontier for multi-receptor agonism. Both are discussed here strictly as research compounds; nothing on this page is medical advice or a dosing guide.
REFERENCES (PUBMED)
- [Semaglutide] Safety of Semaglutide — Front Endocrinol (Lausanne) 2021. PMID 34305810
- [Semaglutide] A systematic review of the effect of semaglutide on lean mass: insights from clinical trials — Expert Opin Pharmacother 2024. PMID 38629387
- [Semaglutide] Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical Trial — JAMA 2021. PMID 33755728
- [Retatrutide] Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial — N Engl J Med 2023. PMID 37366315
- [Retatrutide] Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial — Nat Med 2024. PMID 38858523
- [Retatrutide] Incretin triple agonist retatrutide (LY3437943) alleviates obesity-associated cancer progression — NPJ Metab Health Dis 2025. PMID 40094000
FREQUENTLY ASKED
What is the difference between Semaglutide and Retatrutide?
Semaglutide targets one receptor; retatrutide targets three, adding GIP and glucagon receptor agonism. Retatrutide’s data are from phase 2; semaglutide’s from a completed phase 3 programme.
What is the regulatory status of Semaglutide and Retatrutide?
Semaglutide: Approved medicine (type 2 diabetes and chronic weight management) in many countries, with a large phase 3 programme (STEP, SUSTAIN, SELECT). Prescription-only in South Africa. Retatrutide: Investigational triple agonist in phase 3 trials; not an approved medicine.
What safety signals have been reported?
Semaglutide: Reviews document gastrointestinal effects as the most common; pancreatitis, gallbladder events and the effect on lean mass are active topics. Trials show weight regain after stopping. Retatrutide: Phase 2 trials reported mainly gastrointestinal adverse events and dose-related heart-rate increases.
Which studies is this comparison based on?
For Semaglutide: “Safety of Semaglutide” (PMID 34305810); “A systematic review of the effect of semaglutide on lean mass: insights from clinical trials” (PMID 38629387); “Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical Trial” (PMID 33755728). For Retatrutide: “Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial” (PMID 37366315); “Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial” (PMID 38858523); “Incretin triple agonist retatrutide (LY3437943) alleviates obesity-associated cancer progression” (PMID 40094000).
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