Not Yet RecruitingPhase 2

Myocardial Metabolic Flux in Pulmonary Arterial Hypertension

32 participantsStarted 2026-10-01

Plain-language summary

The rationale for this study is that GLP-1 agonist treatment is likely to influence myocardial substrate utilisation, changing the predominant source of metabolic energy within the heart to a more energetically efficient form. This is represented by a surrogate for improved mitochondrial efficiency with reduction in myocardial lactate levels (produced by inefficient myocardial glycolysis, prevalent in the ventricles of patients with pulmonary hypertension), which can be measured by 31P-magnetic resonance spectroscopy (31P-MRS).

Who can participate

Age range

18 Years – 85 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: \- 1. Diagnosis of Group 1 PAH confirmed by right heart catheterisation under the National Pulmonary Hypertension Service, Royal Brompton Hospital, part of GSTT Foundation Trust 2. Age over 18, less than 85 years 3. Able to give informed consent 4. On a stable dose of PAH-specific therapies (e.g., ERA, PDE5i) for at least 3 months. 5\. Clinically justified prescription of GLP-1 agonist Semaglutide based on following criteria: BMI \> 30 or BMI \> 27 with at least one cardiovascular co-morbidity (systemic hypertension, diabetes, pre-diabetes, COPD, atrial fibrillation, dyslipidaemia, sleep disordered breathing) Exclusion Criteria: * • 1. Pregnancy * 2\. Myocardial infarction within the previous 3 months * 3\. Contraindications to MRI: Pacemakers, metallic implants, or severe claustrophobia. * 4\. Severe renal impairment: eGFR \< 15ml/min/1.73m. * 5\. Current use of SGLT2 inhibitors or GLP-1 agonist therapy (which significantly alter fuel substrate preference) or insulin therapy that cannot be held for the fasting scan

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Change in the phosphocreatine-to-adenosine triphosphate (31PCr/ATP) ratio between baseline and follow up in response to treatment with GLP-1 agonist

Timeframe: 12 weeks

Trial details

NCT IDNCT07737522

SponsorImperial College London

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2028-10-01

View on ClinicalTrials.gov More Pulmonary Arterial Hypertension trials