What the human research shows
A well-run phase 2 with an unusual pharmacology — it blocks the receptor tirzepatide activates — and a monthly schedule. Grade B rather than C because the trial was large for its phase and fully published; the effect size sits below the weekly incretins so far.
Evidence profile0–5
- Metabolic & weightB3.5
- Cardiovascular—0.0
- Muscle & growth—0.0
- Healing & repair—0.0
- Neuro & sleep—0.0
- Immune & inflammation—0.0
- Sexual & hormonal—0.0
- Skin & appearance—0.0
- Ageing & longevity—0.0
| Outcome | Grade | Effect size | Human studies | Where the evidence comes from |
|---|---|---|---|---|
| Body weight (obesity) | BProbable | Large | 1 phase 2 RCT (465 in the obesity cohort, 52 wk) | Six dosing regimens of 140–420 mg every four or eight weeks. Intention-to-treat loss ranged from 12.3% to 16.2% against 2.5% on placebo. In the 127-person diabetes cohort, 8.4–12.3% against 1.7%.1 |
| Blood glucose (HbA1c) in type 2 diabetes | BProbable | Large | Same RCT, diabetes cohort (n=127) | HbA1c fell 1.2–1.6 points against 0.1 on placebo.1 |
| GI side effectsadverse | BProbable | Large | Same RCT | Nausea and vomiting were frequent, particularly without dose escalation; the regimens that started low and stepped up were better tolerated, which is why phase 3 uses escalation.1 |
Literature searched to 23 September 2026. Human studies only; animal and cell work informs the mechanism section and nothing else.
Registered trials
ClinicalTrials.gov lists 28 interventional studies naming Maridebart cafraglutide as an intervention — 11 completed, 5 recruiting, and 2 with results posted to the registry.
A registration is not a result. Anyone can register a study, and many never report — so this list shows what has been attempted, not what has been shown. The graded evidence above is the answer to whether something works.
20 further studies are registered. Participant counts marked * are the sponsor's estimate, not a final enrolment. Source: ClinicalTrials.gov, read directly from the registry and refreshed weekly.
What it is
MariTide is a conjugate: a monoclonal antibody that antagonises the GIP receptor, with two GLP-1 receptor agonist peptides chemically linked to it. The antibody's long half-life is what allows monthly — possibly less frequent — injection. It is strictly a peptide–antibody hybrid, included here because the active pharmacology is peptide and because it is one of the most-searched names in the category.
Amgen is running the MARITIME phase 3 programme in obesity, with and without diabetes.
How it is thought to work
The GLP-1 peptides do what semaglutide does. The antibody part blocks GIP signalling — the opposite of tirzepatide, which activates it. That both strategies reduce weight is one of the open puzzles of the field; long-term GIP agonism may desensitise the receptor, making the two approaches less different than they look.
What is still unknown
- Whether monthly dosing holds weight loss as well as weekly drugs over years.
- Long-term effects of chronic GIP receptor blockade, which no approved drug does.
- Immunogenicity of the antibody with repeated dosing.
The molecule and how long it lasts
A monoclonal antibody conjugated to two GLP-1 peptides — no small-molecule record
- Route
- Subcutaneous, every 4 weeks
- Half-life
- About 14–16 days for the intact molecule (21–24 days total)
From a published human pharmacokinetic study: Véniant MM, et al. A GIPR antagonist conjugated to GLP-1 analogues promotes weight loss with improved metabolic parameters in preclinical and phase 1 settings. Nat Metab 2024;6:290–303
Regulatory status
Investigational.
Investigational; phase 3 running. Products sold as 'MariTide' online are not the trial drug and cannot be, given the manufacturing involved.
No MHRA licence.
Investigational only.
No Drug Identification Number.
Unapproved anywhere, so S0 (non-approved substances).
Questions people actually ask
Is MariTide a peptide?
How does MariTide compare with tirzepatide?
Can you buy MariTide?
One page per claimed effect
- BDoes Maridebart cafraglutide help with body weight?1 phase 2 RCT (465 in the obesity cohort, 52 wk)
- BDoes Maridebart cafraglutide help with blood glucosein type 2 diabetes?Same RCT, diabetes cohort (n=127)
- BHow common is GI side effects with Maridebart cafraglutide?Same RCT
References
- 1Jastreboff AM, et al. Once-monthly maridebart cafraglutide for the treatment of obesity — a phase 2 trial.N Engl J Med, 2025592 enrolled; obesity and obesity-diabetes cohorts; 52 weeks. NCT05669599.
Change log
- 2026-09-23Initial publication from the NEJM phase 2. Grade B.