What is the main difference between mazdutide and tirzepatide?

The second receptor. Mazdutide is a GLP-1 and glucagon receptor dual agonist; tirzepatide is a GLP-1 and GIP receptor dual agonist. Both are once-weekly peptides sharing a GLP-1 receptor arm.

Is one more effective than the other?

No head-to-head randomised trial between mazdutide and tirzepatide has been published, so no comparative effectiveness statement can be supported. Each compound has its own published trial record.

What is oxyntomodulin and why does it matter here?

Oxyntomodulin is a naturally occurring proglucagon-derived peptide with activity at both the GLP-1 and glucagon receptors. Mazdutide is engineered from that dual-activity scaffold, which is the structural reason its second arm is glucagon rather than GIP.

Which compound should a laboratory choose?

It depends on the receptor being studied. Glucagon receptor pharmacology calls for mazdutide, GIP receptor pharmacology calls for tirzepatide. Neither is supplied for human or animal use.

Metabolic Research

Mazdutide vs Tirzepatide: Receptor Profile Comparison

Mazdutide and tirzepatide are both once-weekly dual receptor agonists, but they engage different receptor pairs. Mazdutide acts at the GLP-1 and glucagon receptors; tirzepatide acts at the GLP-1 and GIP receptors. This page compares the two at the level of receptor pharmacology and published clinical-programme status only. No superiority claim is made, and no outcome is compared between compounds.

Mazdutide profile →Tirzepatide profile →

Side-by-side comparison

Attribute	Mazdutide	Tirzepatide
Receptor targets	GLP-1 receptor + glucagon receptor (GCGR)	GLP-1 receptor + GIP receptor (GIPR)
Molecular scaffold	Oxyntomodulin-based peptide analogue	Engineered synthetic incretin peptide
Development codes	IBI362, LY3305677	LY3298176
Originator / developer	Eli Lilly, developed in China by Innovent Biologics	Eli Lilly
Published programme stage	Phase 3 published 2025 (NEJM); approved by China NMPA 27 June 2025	Approved in the UK, EU and US
Peptx availability	Stocked as a single vial reference material	Stocked reference material

Detailed analysis

Mazdutide (development codes IBI362 and LY3305677, Innovent Biologics under licence from Eli Lilly) is built on the mammalian oxyntomodulin scaffold. Oxyntomodulin is a naturally occurring proglucagon-derived peptide with intrinsic activity at both the glucagon-like peptide-1 receptor (GLP-1R) and the glucagon receptor (GCGR), and mazdutide is engineered from that dual-activity template for once-weekly exposure. Tirzepatide is a synthetic peptide engineered for activity at GLP-1R and at the receptor for glucose-dependent insulinotropic polypeptide (GIPR). GIP and glucagon are distinct hormones acting through distinct class B G-protein-coupled receptors, so the second arm of each molecule recruits a different signalling axis. The practical consequence for laboratory work is that the two compounds are not interchangeable reference materials. A study designed around GCGR occupancy or proglucagon-family cross-reactivity requires mazdutide; a study designed around GIPR signalling requires tirzepatide. Both share the GLP-1R arm, which is why they are frequently discussed together in the incretin literature. Published clinical-programme status differs as well. Mazdutide phase 1b results appeared in EClinicalMedicine in 2021, phase 2 results in Nature Communications in 2023, and phase 3 GLORY-1 results in the New England Journal of Medicine in 2025; Innovent announced Chinese NMPA approval for chronic weight management on 27 June 2025. Tirzepatide has an internationally approved regulatory record including the United Kingdom, European Union and United States. Neither compound is supplied here for human use.

Key differences

·The second receptor arm differs: glucagon receptor for mazdutide, GIP receptor for tirzepatide. The GLP-1 receptor arm is shared.
·Mazdutide derives from the oxyntomodulin scaffold, a naturally occurring proglucagon-derived peptide; tirzepatide is an engineered incretin analogue without an oxyntomodulin parent.
·Regulatory footprint differs: mazdutide is approved in China only, tirzepatide has approvals across the UK, EU and US.
·Reference-material selection follows the receptor question. GCGR work needs mazdutide, GIPR work needs tirzepatide.
·No comparative efficacy or safety conclusion can be drawn between the two: there is no published head-to-head randomised trial.

Research summary

Mazdutide and tirzepatide are best understood as two different answers to the same design question: which second receptor to pair with GLP-1R. Because no head-to-head randomised trial between the two has been published, any cross-compound outcome comparison would be indirect and is not made here. Outcome figures for each compound are reported only in their own trial publications, and Peptx reproduces such figures as direct quotations with attribution rather than as claims. Both compounds are supplied strictly as laboratory research reference materials.