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Mazdutide vs Retatrutide: Two Pipeline Agonists, Compared Carefully

Mazdutide (mazdutide (IBI362 / LY3305677), Innovent Biologics / Eli Lilly) vs Retatrutide (retatrutide (LY3437943), Eli Lilly)

Last verified July 2026

By Ruth Calder · Enforcement Editor
Editorially reviewed & fact-checked against primary sources · How we verify contentLast reviewed

The verdict

⚠ These numbers are not comparable and the difference in endpoints is doing most of the work: −11.3% at 24 weeks for mazdutide at 6 mg (PMID 38092790) against −24.2% at 48 weeks for retatrutide at 12 mg (PMID 37366315). Twenty-four weeks against forty-eight, in different trials. Both are GLP-1 plus glucagon agonists, with retatrutide adding GIP; mazdutide is developed principally for China. Neither is FDA-approved.

Side-by-side comparison

FieldMazdutideRetatrutide
MechanismGLP-1 / glucagon dual receptor agonist (GLP-1R + GcgR)GLP-1 / GIP / glucagon triple receptor agonist (GLP-1R + GIPR + GcgR)
Phase 2 peak weight loss−11.3% at 24 wk (6 mg; PMID 38092790, Nature Communications 2023) — cross-trial, 24-wk endpoint vs retatrutide's 48-wk endpoint; not directly comparable−24.2% at 48 wk (12 mg; PMID 37366315, NEJM 2023) — cross-trial, not directly comparable to mazdutide figure
Phase 3 weight-loss dataGLORY-1 (PMID 40421736, NEJM 2025): −12.55% at 32 wk (6 mg) in Chinese adults; GLORY-2 (PMID 42251595, JAMA 2026): 9 mg dose evaluated in Chinese adultsSURMOUNT-PLUS phase 3 ongoing; no primary results published as of mid-2026
Trial stage / statusPhase 3 complete (GLORY-1 2025, GLORY-2 2026); conducted primarily in China; US regulatory status: investigationalPhase 2 complete; phase 3 (SURMOUNT-PLUS) ongoing globally; no phase-3 results published
Geographic scope / regulatory statusPhase 3 trials conducted in China; regulatory filing in China (NMPA) in progress; not FDA-approved for US marketGlobal phase-3 program; not FDA-approved
MASH / liver-disease evidenceNo dedicated MASH or liver-disease clinical trial publishedNo dedicated MASH or liver-disease clinical trial published
AdministrationOnce-weekly subcutaneous injectionOnce-weekly subcutaneous injection
FDA approval statusNot FDA-approved; investigational (US)Not FDA-approved; investigational (US)

Frequently asked questions

Which works better for weight loss, Mazdutide or Retatrutide?

Mazdutide recorded −11.3% at 24 wk (6 mg; PMID 38092790, Nature Communications 2023) — cross-trial, 24-wk endpoint vs retatrutide's 48-wk endpoint; not directly comparable; Retatrutide recorded −24.2% at 48 wk (12 mg; PMID 37366315, NEJM 2023) — cross-trial, not directly comparable to mazdutide figure. ⚠ These come from separate trials with different protocols and populations, so the gap between two numbers from two studies is weaker evidence than it looks. No head-to-head trial of this pair is on record here.

Are Mazdutide and Retatrutide the same drug?

No. Mazdutide is mazdutide (IBI362 / LY3305677) and Retatrutide is retatrutide (LY3437943) — different molecules, and they work differently: GLP-1 / glucagon dual receptor agonist (GLP-1R + GcgR) against GLP-1 / GIP / glucagon triple receptor agonist (GLP-1R + GIPR + GcgR). Results with one do not predict results with the other.

How is each one taken?

Mazdutide: Once-weekly subcutaneous injection. Retatrutide: Once-weekly subcutaneous injection. Worth weighing honestly against your own habits — the best drug for you is partly the one you will still be taking in eight months, and a dosing routine that does not fit a life gets abandoned.

Can I switch from Mazdutide to Retatrutide?

Yes, with a prescriber. Expect to re-titrate from the bottom of the new drug's ladder rather than starting where you left off: these are different molecules and tolerance to one does not transfer to the other. Both the old drug's washout and the new drug's schedule apply.

Which one should I ask for?

That is a prescriber's call, and anyone answering it from a table is guessing. What a page like this can do is tell you what the trials measured, what the manufacturers charge, and where the evidence is still missing, so the conversation starts from the record rather than from an advertisement.

References

  1. 1.Jastreboff AM, Karol A, Stefanski A, et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial New England Journal of Medicine. 2023. PMID: 37366315.
  2. 2.Ji L, Jiang H, Cheng Z, et al. A phase 2 randomised controlled trial of mazdutide in Chinese overweight adults or adults with obesity Nature Communications. 2023. PMID: 38092790.
  3. 3.Ji L, Jiang H, Bi Y, et al. Once-Weekly Mazdutide in Chinese Adults with Obesity or Overweight New England Journal of Medicine. 2025. PMID: 40421736.
  4. 4.Gao L, Jiang H, Cai H, et al. Treatment With 9-mg Mazdutide for Weight Reduction in Chinese Adults With Obesity: The GLORY-2 Randomized Clinical Trial JAMA. 2026. PMID: 42251595.
  5. 5.Gadde KM, Talebloo J, Heymsfield SB, et al. Mazdutide and Orforglipron — New Evidence in Obesity and Diabetes JAMA. 2026. PMID: 42251768.
  6. 6.Ji L, et al. Mazdutide 9 mg in Chinese adults with a body mass index ≥30 kg/m² but without diabetes Med (New York). 2026. PMID: 41875890.

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