AuthorisedTherapeutic use (Phase IV)Interventional

A study on stopping versus continuing beta-blockers in patients with hypertrophic cardiomyopathy treated with mavacamten

Hypertrophic cardiomyopathy is a heart condition where the heart muscle becomes thicker than normal. This can block blood flow and cause shortness of breath, chest pain, and tiredness. Many people take beta-blocker tablets to help manage these symptoms. A newer medicine called mavacamten has become available, which helps the heart relax and eases blood flow. Because mavacamten is effective on its own, doctors want to know if patients still need to take beta-blockers as well. Taking fewer tablets could reduce side effects such as fatigue and low energy. In this study, researchers will compare people who continue taking their beta-blockers with those who carefully stop taking them, while everyone stays on mavacamten. The goal is to see which approach provides the best heart health and quality of life.

At a glance

Status

Authorised

Phase

Therapeutic use (Phase IV)

Sponsor

Ziekenhuis Oost Limburg

Enrolment target

Start

13 Oct 2026

Obstructive Hypertrophic Cardiomyopathy.

What is this study about?

Hypertrophic cardiomyopathy (HCM) is an inherited condition that causes parts of the heart muscle to thicken. In the 'obstructive' type, this thickening gets in the way of blood leaving the heart, making the heart work much harder. For many years, beta-blocker tablets have been the standard treatment to slow the heart rate and ease symptoms. Recently, a targeted drug called mavacamten was introduced. It works differently by directly reducing the excessive contractions of the heart muscle.

Now that mavacamten is in regular use, a practical question has arisen: do patients still need their beta-blockers? Beta-blockers can cause bothersome side effects for some people, such as feeling sluggish, dizzy, cold, or low in mood. If mavacamten is already controlling the heart condition well, taking beta-blockers at the same time might no longer be necessary.

This study aims to answer that question clearly and safely. Participants taking both medicines will be divided into two groups: one group will continue their beta-blocker as usual, while the other group will carefully reduce and stop it under close medical supervision. Both groups will continue taking mavacamten.

By comparing symptom levels, exercise capacity, and heart scans between the two groups, the researchers hope to create clear guidelines for NHS doctors. The results will help future patients avoid taking unnecessary medications while ensuring their heart stays healthy and protected.

Key takeaways

The study tests whether people taking mavacamten can safely stop taking beta-blockers.
It aims to see if stopping beta-blockers improves energy and quality of life without harming heart function.
Stopping the medicine is done slowly under close medical monitoring to ensure patient safety.
Participation involves clinic visits, heart scans (echocardiograms), and symptom tracking.
You can withdraw from the study at any time and return to your usual treatment plan.

Who may be eligible?

This trial is open to adults aged 18 and older who have been diagnosed with obstructive hypertrophic cardiomyopathy. To be considered, you must already be taking mavacamten as well as a daily beta-blocker tablet to manage your heart condition.

You might not be able to join if you need beta-blockers for another vital medical reason, such as a severe heart rhythm problem or uncontrolled high blood pressure. You must also be stable on your current medicines so doctors can safely monitor any changes.

Your study doctor will review your full medical history, run routine heart scans, and check that you are not pregnant or planning a pregnancy, as some heart medicines are not safe during pregnancy.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

I am aged 18 or older.
I have been diagnosed with obstructive hypertrophic cardiomyopathy (oHCM).
I am currently taking mavacamten for my heart condition.
I am also taking a regular beta-blocker tablet.
My heart condition and medicines are currently stable.

Answer every question to see your result.

What does participation involve?

Taking part usually involves visiting a hospital clinic several times over a few months to a year. At the start, the study team will carry out health checks, which may include an ultrasound of your heart (an echocardiogram), an ECG heart tracing, blood tests, and questions about your daily symptoms.

If you join, you will be placed into one of two groups: one will keep taking their regular beta-blocker, and the other will gradually taper off and stop it. Neither you nor your doctor will have to guess the plan, as stopping the medicine is done very slowly to avoid sudden changes in your heart rate. Throughout the study, you will continue taking mavacamten as prescribed. You will have regular check-ups to monitor your heart and blood pressure, and you can contact the medical team at any point if you feel unwell.

Potential risks and benefits

A potential benefit of joining is that if you stop beta-blockers, you might experience fewer side effects like fatigue or slow heart rates, which could improve your daily energy. You will also receive very close heart monitoring from specialist teams. However, there is a risk that reducing your beta-blocker could temporarily cause symptoms such as heart palpitations, mild breathlessness, or a rise in blood pressure. Your safety is the top priority, and if symptoms return, your doctor can restart your usual treatment right away. You are free to leave the study at any time without giving a reason, and your regular NHS care will not be affected.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Belgium

Common questions

What is mavacamten?

Mavacamten is a newer medicine specifically designed to relax thickened heart muscle in people with obstructive hypertrophic cardiomyopathy, helping blood flow more freely.

Why do doctors want to test stopping beta-blockers?

Beta-blockers can cause side effects like tiredness and cold hands. If mavacamten is working well, taking beta-blockers too might be unnecessary extra medication.

Will I have to stop my beta-blocker suddenly?

No. If you are chosen to stop, it is done gradually and under close medical supervision to keep your heart rate and blood pressure stable.

What happens if my symptoms get worse after stopping?

The research team monitors you closely. If your symptoms return or your heart rate rises too much, your doctor can safely put you back on your beta-blocker.

Can I leave the trial if I change my mind?

Yes. Taking part is completely voluntary. You can stop participating at any time, and your usual NHS heart care will continue as normal.