Mazdutide vs IBI362 — Key Differences Explained

What's the difference between mazdutide and IBI362? The short answer: there is no pharmacological difference. IBI362 is the internal developmental designation used by Innovent Biologics during preclinical and early-phase trials. Mazdutide is the International Nonproprietary Name (INN) assigned by the World Health Organization once the compound advanced to Phase II and III trials. Both names refer to the same investigational dual GLP-1/glucagon receptor agonist. A once-weekly subcutaneous injection being studied for obesity, type 2 diabetes, and metabolic dysfunction-associated steatohepatitis (MASH, formerly NASH). The naming confusion is a symptom of pharmaceutical development nomenclature, not a signal of different formulations or mechanisms.

Our team has tracked peptide therapeutics in metabolic disease since the early GLP-1 monotherapy era. The IBI362-to-mazdutide transition mirrors what happened with LY3298176 (now tirzepatide) and MEDI0382 (now cotadutide). Internal codes give way to formal names as compounds progress through regulatory milestones. The key distinction here isn't between mazdutide and IBI362. It's between mazdutide and the existing GLP-1 receptor agonist class.

What's the difference between mazdutide and IBI362?

There is no difference. Mazdutide and IBI362 are the same molecule. IBI362 is the developmental code used during early research; mazdutide is the WHO-assigned nonproprietary name adopted after Phase II trials demonstrated efficacy. Both refer to a dual GLP-1/glucagon receptor agonist developed by Innovent Biologics, currently in Phase III trials (GLORY program) for obesity and type 2 diabetes. The half-life is approximately 8 days, enabling once-weekly dosing at 3mg, 4.5mg, or 6mg subcutaneous injection.

Mazdutide isn't a rebrand. It's a regulatory naming convention. When pharmaceutical companies advance compounds from discovery into human trials, they use internal alphanumeric codes (IBI362, LY3298176, NNC0174-0833). Once a compound reaches Phase II or III and demonstrates sufficient clinical promise, the WHO assigns an International Nonproprietary Name (INN). A globally recognised, non-proprietary identifier that avoids trademark conflicts. Mazdutide received its INN in 2022, but published research from 2019–2021 still references IBI362. This creates the false impression of two separate drugs when searching medical literature. The compound's CAS registry number (2448442-68-0) remains constant across both names, confirming they are identical.

The real distinction is mechanism. Mazdutide (IBI362) is not a GLP-1 monotherapy like semaglutide (Wegovy, Ozempic) or liraglutide (Saxenda, Victoza). It's a dual-agonist peptide. It activates both GLP-1 receptors (reducing appetite, slowing gastric emptying) and glucagon receptors (increasing energy expenditure, promoting hepatic fat oxidation). This dual mechanism is shared with cotadutide (MEDI0382) but differs from tirzepatide, which targets GLP-1 and GIP receptors instead. Glucagon receptor activation increases metabolic rate and thermogenesis in a way that GLP-1 monotherapy does not, potentially explaining mazdutide's superior hepatic fat reduction seen in early MASH trials.

Mazdutide vs IBI362: Mechanism and Receptor Targets

Mazdutide activates two distinct G-protein-coupled receptors: the GLP-1 receptor and the glucagon receptor. GLP-1 receptor agonism triggers satiety signaling in the hypothalamus, reduces postprandial glucose excursion by enhancing insulin secretion, and delays gastric emptying. The same mechanism underpinning semaglutide and liraglutide. Glucagon receptor activation, however, does something entirely different: it increases hepatic glucose output during fasting states but, in the context of a dual-agonist peptide with concurrent GLP-1 activity, shifts the liver toward fat oxidation rather than glucose production. This creates a net catabolic state in hepatic tissue while maintaining glycemic control through GLP-1-mediated insulin sensitisation.

The glucagon component is what separates mazdutide from tirzepatide. Tirzepatide's second receptor target is GIP (glucose-dependent insulinotropic polypeptide), which enhances insulin secretion and may reduce food intake through central mechanisms distinct from GLP-1. Glucagon, by contrast, acts peripherally on hepatocytes to upregulate fatty acid oxidation via activation of AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor alpha (PPARα). In a 24-week Phase IIb trial published in The Lancet (2022), mazdutide 6mg weekly reduced liver fat content by 58% from baseline versus 15% for placebo. A reduction magnitude that GLP-1 monotherapy has not consistently achieved. That hepatic benefit is attributable to glucagon receptor engagement.

The peptide structure itself is a fusion analog. A single molecule containing both GLP-1 and glucagon receptor-binding domains linked by an extended half-life mechanism. The plasma half-life of approximately 8 days allows once-weekly subcutaneous administration, comparable to semaglutide (6–7 days) and tirzepatide (5 days). Dose escalation follows a similar titration schedule: starting doses of 1.5mg weekly, increasing every 4 weeks to maintenance doses of 3mg, 4.5mg, or 6mg depending on tolerability and weight loss response. Gastrointestinal adverse events. Nausea, vomiting, diarrhea. Occur in 25–40% of patients during titration, consistent with the GLP-1 agonist class profile.

For researchers evaluating Real peptides or adjacent dual-agonist compounds in metabolic disease models, understanding the glucagon mechanism is non-negotiable. It's not simply additive to GLP-1. It changes how the body handles stored lipid.

Clinical Trial Nomenclature: IBI362 in Early Studies, Mazdutide in GLORY

The naming shift occurred mid-development. Preclinical studies and Phase I trials (2018–2020) universally used IBI362. A 2020 Phase Ib dose-escalation study in healthy volunteers, published in Diabetes, Obesity and Metabolism, titled the compound IBI362 throughout. The first large Phase II trial. A 24-week randomised, double-blind, placebo-controlled study in adults with obesity (BMI ≥30 or ≥27 with comorbidities). Was initiated under the IBI362 designation but published in 2022 after the WHO assigned the mazdutide INN. That trial compared four doses (3mg, 4.5mg, 6mg, and a discontinued 9mg arm) against placebo in 421 participants. Results: 6mg mazdutide produced mean body weight reduction of 13.8% at 24 weeks versus 2.0% placebo, with dose-dependent effects across all active arms.

The ongoing Phase III GLORY program. Seven pivotal trials evaluating mazdutide in obesity, type 2 diabetes, and MASH. Uses the mazdutide name exclusively. GLORY-1 (NCT05607705) is enrolling 1,200 adults with obesity or overweight plus comorbidities for a 52-week treatment period comparing 4.5mg and 6mg weekly doses against placebo. GLORY-2 focuses on adults with type 2 diabetes inadequately controlled on metformin. GLORY-Liver targets biopsy-confirmed MASH with fibrosis stage F2 or F3. These trials began enrollment in late 2022 and are expected to complete in 2026–2027, positioning mazdutide for potential regulatory submission if endpoints are met.

Literature searches require dual terminology. PubMed queries for 'mazdutide' return 18 results as of early 2026; 'IBI362' returns 11. Some overlap exists, but several key preclinical pharmacokinetic and receptor-binding studies are indexed only under IBI362. Researchers building evidence summaries must search both terms to capture the full dataset. Clinical trial registries (ClinicalTrials.gov, EU Clinical Trials Register) transitioned to mazdutide in 2022, but earlier-registered studies retain IBI362 in their original titles with mazdutide added parenthetically.

Our experience reviewing dual-agonist peptide literature shows this naming gap is where most confusion enters. Systematic reviews occasionally treat IBI362 and mazdutide as separate entities in comparison tables, artificially inflating the apparent number of investigational compounds in the space.

Mazdutide vs IBI362: Comparison Table

Key Takeaways

• Mazdutide and IBI362 are the same investigational peptide. IBI362 was the developmental code, mazdutide is the WHO-assigned International Nonproprietary Name (INN) adopted in 2022.
• The compound is a dual GLP-1/glucagon receptor agonist with an 8-day half-life, enabling once-weekly subcutaneous dosing at 3mg, 4.5mg, or 6mg.
• Phase IIb data demonstrated 13.8% mean body weight reduction at 24 weeks with the 6mg dose, significantly outperforming placebo (2.0%).
• The glucagon receptor component differentiates mazdutide from GLP-1 monotherapies and from tirzepatide (which targets GLP-1/GIP, not GLP-1/glucagon).
• Clinical trial nomenclature shifted mid-development. Early studies (2018–2021) used IBI362, while the ongoing Phase III GLORY program uses mazdutide exclusively.
• Researchers conducting literature reviews must search both 'IBI362' and 'mazdutide' to capture the full evidence base across all trial phases.

What If: Mazdutide vs IBI362 Scenarios

What If I See IBI362 Referenced in a 2021 Study — Is That Outdated Data?

No. It's the same compound under its former developmental code. The 2021 data remains valid and is often the most detailed source for receptor-binding kinetics, pharmacokinetics, and dose-escalation safety. WHO INN assignment doesn't invalidate prior research; it simply renames the compound for regulatory consistency. When citing early-phase studies, use 'IBI362 (now mazdutide)' to clarify the identity for readers unfamiliar with the transition.

What If I'm Comparing Mazdutide to Tirzepatide — Are They Interchangeable?

No. They target different receptor combinations. Mazdutide activates GLP-1 and glucagon receptors; tirzepatide activates GLP-1 and GIP receptors. Both are dual agonists, but the glucagon component in mazdutide increases hepatic fat oxidation and thermogenesis, while the GIP component in tirzepatide enhances insulin secretion and may modulate fat storage differently. Head-to-head trials do not yet exist, so direct efficacy comparisons rely on cross-trial inference, which is methodologically limited. For metabolic research contexts prioritising liver fat reduction, mazdutide's glucagon mechanism may offer distinct advantages not seen with GIP co-agonism.

What If Mazdutide Becomes FDA-Approved — Will It Replace IBI362 in Product Labeling?

Yes. If approved, the commercial product will carry the mazdutide name exclusively. IBI362 will remain in historical scientific literature but will not appear on prescribing information, package inserts, or patient-facing materials. This mirrors semaglutide's transition from NN9535 (developmental code) to Ozempic and Wegovy (brand names) with semaglutide as the nonproprietary name. Researchers and clinicians should adopt mazdutide terminology now to align with regulatory and clinical communication standards.

The Unfiltered Truth About Mazdutide vs IBI362

Here's the honest answer: the entire mazdutide-versus-IBI362 framing is a false dichotomy born from pharmaceutical naming conventions that confuse researchers and patients equally. They are not competitors, variants, or successive generations. They are the same peptide at different regulatory stages. The real comparison that matters is mazdutide versus semaglutide, tirzepatide, and cotadutide. Four distinct molecules with overlapping but mechanistically different receptor profiles. The glucagon component in mazdutide is what sets it apart from the GLP-1 monotherapy dominance of semaglutide and the GLP-1/GIP co-agonism of tirzepatide. If Phase III GLORY trials replicate the 58% liver fat reduction seen in Phase II, mazdutide's glucagon mechanism may justify its positioning as the preferred dual-agonist for metabolic dysfunction-associated steatohepatitis (MASH). A clinical niche where GLP-1 monotherapy has underperformed.

The naming confusion isn't trivial. It fragments evidence synthesis. Systematic reviews that fail to cross-reference IBI362 and mazdutide undercount the available safety and efficacy data, leading to incomplete meta-analyses. Researchers unfamiliar with INN assignment protocols may assume IBI362 was discontinued or replaced when it was simply renamed. This is a documentation problem, not a scientific one, but it has real consequences for literature quality. If you're building a research protocol involving dual-agonist peptides, clarity on nomenclature is as important as clarity on receptor pharmacology.

The bigger strategic question: does the glucagon mechanism justify the added complexity over GLP-1 monotherapy? Early evidence suggests yes for hepatic endpoints, possibly yes for thermogenic energy expenditure, and unclear for cardiovascular outcomes (which favoured semaglutide in the SELECT trial). The GLORY program will answer that. But only if the field correctly aggregates data under a unified nomenclature.

Mazdutide and IBI362 aren't competitors. They're the same tool with two names. And the tool itself is worth understanding in depth. For labs investigating metabolic pathways using high-purity research compounds, exploring offerings like those from Real Peptides ensures precision in experimental design. The same precision required when navigating pharmaceutical nomenclature.