How large is the heart failure trial?

MARITIME-HF is recruiting 5,056 participants — larger than most obesity trials in this field.

Is it approved anywhere?

No. It is investigational and available only within registered clinical trials.

Research & Regulatory News

MARITIME: Where the Monthly Compound Is Being Tested

JMWritten & reviewed by Jack Muncaster · Founder, UK PeptidesLast reviewed 2026-08-234 cited sources

Maridebart cafraglutide is in a multi-trial Phase 3 programme under the MARITIME name, registered across obesity, obstructive sleep apnoea and heart failure indications. The heart failure trial alone enrols 5,056 participants.

Key facts

MARITIME-HF: NCT07037459, recruiting, n=5,056
MARITIME-OSA-2: NCT07226765, recruiting, n=250
MARITIME-3-J: NCT06987695, active not recruiting, n=279
Phase: 3, all of the above
Phase 2 readout: NEJM, 4 September 2025
Authorisation: None — investigational

What the programme covers

More than weight. The registered Phase 3 trials verified on ClinicalTrials.gov span obesity, obstructive sleep apnoea and heart failure with preserved or mildly reduced ejection fraction. A compound entering Phase 3 across three organ-system indications simultaneously is being developed as a metabolic agent from the outset.

The scale of the heart failure trial

MARITIME-HF, NCT07037459, is recruiting 5,056 participants. That is larger than most obesity trials in this field and comparable to a dedicated cardiovascular outcome programme. Enrolment on that scale is committed only where the endpoint requires it — which points to hard clinical events rather than a surrogate.

Research material referenced

Retatrutide 10mg — third-party HPLC tested

View — £59.99

Why sleep apnoea appears here too

Obstructive sleep apnoea is strongly associated with obesity, and tirzepatide has already been studied in it. A second compound entering the same indication indicates the field regards it as an established rather than speculative extension of incretin pharmacology.

Why regional trials appear separately

MARITIME-3-J is a separate registration with 279 participants. Regional trials exist because regulators in some jurisdictions require data in their own populations, and because BMI thresholds and body composition differ enough that a global trial does not automatically answer a local question.

What Phase 3 breadth does not establish

Efficacy. A large multi-indication Phase 3 programme reflects a sponsor's assessment that Phase 2 justified the investment — Jastreboff and colleagues published that Phase 2 in the New England Journal of Medicine in September 2025. Compounds enter Phase 3 across several indications and fail, and the programme is the question rather than the answer.

Current status

Maridebart cafraglutide holds no marketing authorisation anywhere and is available only within registered clinical trials. Nothing supplied here is related to it, and no research material is an alternative to any investigational or licensed medicine.

Extended research context

The Research & Regulatory News deep dive

Deep dive: why 2026 was the year the incretin field split in two

For a decade every meaningful GLP-1 medicine was a peptide, and every one of them was injected. 2026 broke that pattern in both directions at once. In August the MHRA authorised orforglipron, a small molecule with no peptide bonds that works as an ordinary daily tablet. Three months earlier, retatrutide's TRIUMPH-1 reported a 28.3% mean weight reduction — the largest figure yet from a single molecule, and achievable only with a peptide capable of engaging three receptors at once. The field is not converging on one answer; it is separating into a convenience track and a magnitude track, and those tracks have different chemistry.

Deep dive: what a marketing authorisation actually means

An authorisation is granted to a specific product, in a specific formulation, for a specific indication, by a specific regulator. It is not a statement about a compound class and it does not transfer. Orforglipron being licensed in the UK tells you nothing about the legal or regulatory status of any other incretin, and nothing at all about compounds that remain investigational. Authorisation is also separate from funding: a licensed medicine is not automatically available on the NHS, which requires a further NICE appraisal.

Deep dive: reading trial results without being misled

Headline percentages are the least transferable part of a trial. A figure is only meaningful alongside its population, its duration, its comparator and its dropout rate. TRIUMPH-1's 28.3% came from an 80-week study in a relatively uncomplicated obesity population; TRIUMPH-3's 22.6% came from adults with severe obesity and established cardiovascular disease, and the gap between those two numbers is mostly population, not potency. Discontinuation rates deserve the same attention as efficacy: 11.3% of the TRIUMPH-1 12 mg arm stopped due to adverse events against 4.9% on placebo, and that figure is routinely dropped from summaries.

Research applications

▸Tracking regulatory status of investigational incretin compounds
▸Understanding the difference between authorisation, NICE appraisal and NHS availability
▸Comparing peptide and non-peptide receptor agonist pharmacology
▸Interpreting Phase 3 topline releases before peer-reviewed publication
▸Verifying trial identity against ClinicalTrials.gov registrations

Handling checklist

✓Check the compound named in a trial registration matches the compound being discussed
✓Confirm the NCT identifier resolves to the acronym being cited
✓Read topline press releases as preliminary until peer-reviewed publication
✓Separate the trial population from the headline percentage before comparing studies
✓Treat authorisation in one jurisdiction as saying nothing about status in another

Common research-handling mistakes

Learnt from thousands of researcher orders across our UK labs.

✗ Treating a positive Phase 3 as approval

Fix: Filing begins a review that commonly takes a year or more and can end in a request for more data.

✗ Comparing weight-reduction percentages across different trials

Fix: Population, duration and comparator differ; the numbers are not interchangeable.

✗ Assuming one incretin's approval legitimises another compound

Fix: Authorisations are product-specific and do not transfer between compounds.

✗ Citing a TRIUMPH number without checking the NCT identifier

Fix: Verify against ClinicalTrials.gov — the numbering has been widely misreported.

✗ Reading research material as an alternative to a licensed medicine

Fix: Research material is supplied for laboratory use only and is not a substitute for anything prescribed.

Continue researching

Peer-reviewed guides, comparators and matched reference materials.

Frequently asked questions

What indications is MariTide being tested in?: Obesity, obstructive sleep apnoea, and heart failure with preserved or mildly reduced ejection fraction, across registered Phase 3 trials.
How large is the heart failure trial?: MARITIME-HF is recruiting 5,056 participants — larger than most obesity trials in this field.
Is it approved anywhere?: No. It is investigational and available only within registered clinical trials.

Primary sources & clinical trials

Peer-reviewed research and registered trials from PubMed, ClinicalTrials.gov, PubChem, FDA and NIH. All links open in a new tab and point to the primary source, so every claim can be verified at origin.

Written and reviewed by

Jack Muncaster · Founder, UK Peptides

Jack founded UK Peptides in Manchester after repeatedly receiving research compounds with missing or recycled paperwork. He is responsible for supplier selection, batch release decisions and the content published in this research library. Every article here is sourced to primary literature and every product page to a signed third-party certificate.

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