Maridebart cafraglutide
Also known as: MariTide, AMG 133
Maridebart cafraglutide (also called MariTide or AMG 133) is an investigational GIP antagonist in the GLP-1 Agonist class. Maridebart cafraglutide is an antibody-peptide conjugate with an unusual design: it antagonises the GIP receptor while activating the GLP-1 receptor. A monoclonal antibody against GIPR is conjugated to GLP-1 analog peptides, so one molecule blocks one incretin receptor and stimulates the other.
For research use only.
Key Facts
- CAS
- 2760218-55-9
- Molecular Weight (MW)
- ≈145–154 kDa (conjugate; assay-dependent)
- Half-life
- Long (monthly or less frequent dosing in trials)
- FDA status
- Investigational New Drug (IND)
- Administration Route
- Subcutaneous
- Frequency
- Monthly or less frequent (per study arm)
- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
- Targets
- GIP receptorGLP-1 receptor
Research summary
Amgen bispecific molecule (GIPR antagonist + GLP-1R agonist) in Phase 2/3 obesity development. Monthly-class PK in trials. Not FDA-approved.
Peptide Library's Maridebart cafraglutide profile summarises 5 cited studies listed in the Science section, the compound's regulatory status, and research-protocol parameters reported for it. It is a research reference, not medical advice.
Protocol
- Dosage Range
- Per trial protocol
- Frequency
- Monthly or less frequent (per study arm)
- Cycle
- Per study
- Administration Route
- Subcutaneous
- Reconstitution Guide
- —
- Injection Sites
- Per protocol
- Timing Notes
- Phase 2 obesity; Phase 3 CV/HFpEF programs initiated
Not yet checked against primary sources
These figures are compiled from earlier reference material. They have not been verified against FDA labelling, registered trials or published literature, no citation is attached to them, and none of them is a recommended dose. Maridebart cafraglutide is queued for dosage evidence review.
Compare reported doses across the whole librarySequence & molecular data
| Molecular formula | — (antibody–peptide conjugate; very high MW) |
|---|---|
| Molecular weight | ≈145–154 kDa (conjugate; assay-dependent) |
| CAS number | 2760218-55-9 |
| Half-life | Long (monthly or less frequent dosing in trials) |
| Appearance | Sterile solution for sc injection (investigational) |
| Formulation | Solution |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Maridebart cafraglutide is an antibody-peptide conjugate with an unusual design: it antagonises the GIP receptor while activating the GLP-1 receptor. A monoclonal antibody against GIPR is conjugated to GLP-1 analog peptides, so one molecule blocks one incretin receptor and stimulates the other. This is the opposite of the tirzepatide approach, which agonises both, and the fact that GIPR agonism and antagonism have each produced weight reduction in trials remains an unresolved question in incretin pharmacology. The antibody scaffold gives a long half-life supporting infrequent dosing. It is investigational.
Origin
Engineered monoclonal antibody–peptide conjugate.
Targets
Studies
- Once-Monthly Maridebart Cafraglutide for the Treatment of Obesity - A Phase 2 Trial
- Design and therapeutic rationale of antibody-peptide conjugates: insights from maridebart cafraglutide (AMG133) and emerging applications
- A GIPR antagonist conjugated to GLP-1 analogues promotes weight loss with improved metabolic parameters in preclinical and phase 1 settings
- Discovery of AMG 133, a Glucose-Dependent Insulinotropic Polypeptide Receptor Antagonist and Glucagon-Like Peptide 1 Receptor Agonist Antibody-Drug Conjugate for the Treatment of Obesity
- Once-Monthly Maridebart Cafraglutide in Obesity - A Phase 2 Trial. Reply
Regulatory & research status
Maridebart cafraglutide has been studied under an Investigational New Drug application. It is not approved for marketing.
| FDA status | Investigational New Drug (IND) |
|---|---|
| Availability | Research-Only |
| WADA (sport) | Banned in Sport |
| Library classification | Clinical Trial |
Benefits
Maridebart cafraglutide side effects
Side Effects
- GI effects
- Antibody-related reactions possible
Storage & stability
Lyophilized (freeze-dried) peptide powder is far more stable than the reconstituted solution. Keep sealed vials cold, dry and away from light; long-term storage is typically frozen, with short-term refrigeration for vials in use.
Once reconstituted in bacteriostatic water, keep the solution refrigerated, avoid repeated freeze–thaw cycles and agitation, and label the vial with the reconstitution date and concentration. Discard any solution that turns cloudy or shows particulates.
Degradation rates differ by sequence: peptides containing methionine, cysteine, asparagine or glutamine are more prone to oxidation and deamidation, so shelf life after reconstitution is compound-specific rather than universal.
Read the full guide: how to store peptides before and after reconstitution →
Source: Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544–575. (PMID 20143256). General guidance for research handling; not product-specific instructions.
Maridebart cafraglutide: frequently asked questions
What is Maridebart cafraglutide?
Amgen bispecific molecule (GIPR antagonist + GLP-1R agonist) in Phase 2/3 obesity development. Monthly-class PK in trials. Not FDA-approved.
How does Maridebart cafraglutide work?
Maridebart cafraglutide is an antibody-peptide conjugate with an unusual design: it antagonises the GIP receptor while activating the GLP-1 receptor. A monoclonal antibody against GIPR is conjugated to GLP-1 analog peptides, so one molecule blocks one incretin receptor and stimulates the other.
Is Maridebart cafraglutide FDA approved?
No. Maridebart cafraglutide is investigational: it is in clinical development and has not been approved by the FDA for any indication. Investigational status means trials are ongoing or complete but regulatory review has not resulted in approval, and efficacy and safety are still being established.
What is the half-life of Maridebart cafraglutide?
Reported half-life for Maridebart cafraglutide is Long (monthly or less frequent dosing in trials). Half-life describes how long the compound persists in circulation, not how long any effect lasts, and published figures vary with route of administration, formulation and the population studied.
Is Maridebart cafraglutide banned in sport?
Maridebart cafraglutide is recorded here as prohibited in sport. Athletes subject to anti-doping rules should check the current WADA Prohibited List directly, since it is revised annually and classifications change.
What peptides are similar to Maridebart cafraglutide?
Compounds most often compared with Maridebart cafraglutide include Retatrutide, Survodutide, Pemvidutide and Cotadutide. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- Once-Monthly Maridebart Cafraglutide for the Treatment of Obesity - A Phase 2 Trial — N Engl J Med, 2025External reference
- Design and therapeutic rationale of antibody-peptide conjugates: insights from maridebart cafraglutide (AMG133) and emerging applications — Antib Ther, 2026External reference
- A GIPR antagonist conjugated to GLP-1 analogues promotes weight loss with improved metabolic parameters in preclinical and phase 1 settings — Nat Metab, 2024External reference
- Discovery of AMG 133, a Glucose-Dependent Insulinotropic Polypeptide Receptor Antagonist and Glucagon-Like Peptide 1 Receptor Agonist Antibody-Drug Conjugate for the Treatment of Obesity — J Med Chem, 2026External reference
- Once-Monthly Maridebart Cafraglutide in Obesity - A Phase 2 Trial. Reply — N Engl J Med, 2025External reference
Related research, comparisons & guides
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Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Aug 30, 2026 · Version 1
This Maridebart cafraglutide profile is compiled from published literature (5 cited studies linked above), public regulatory records and chemical registries. It describes what research reports; it is not medical advice, and nothing here is a dosing recommendation for humans. Peptide Library does not sell peptides. Editorial policy · How profiles are compiled · Report an error
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