AuthorisedTherapeutic exploratory (Phase II)Interventional

Phase II, Multicenter, Randomized Study to Evaluate Safety and Efficacy of MRD-guided Therapy with Reduced versus Standard Dose of Belantamab Mafodotin in Combination with Pomalidomide and Dexamethasone in Patients with Relapsed/Refractory Multiple Myeloma (REBEL)

Multiple myeloma is a type of blood cancer that develops in the bone marrow. When the cancer comes back or stops responding to standard treatments, doctors look for new drug combinations to help control it. This trial, called the REBEL study, tests a treatment combining three medicines: belantamab mafodotin, pomalidomide, and dexamethasone. Belantamab mafodotin can be very effective, but it can also cause problems with the surface of the eyes and temporary changes in eyesight. Doctors want to test whether tracking tiny traces of remaining cancer (called minimal residual disease) allows them to safely lower the dose of belantamab mafodotin. The main aims are to see how well the cancer responds and whether the lower dose helps protect patients' eyesight while keeping the cancer under control. Patients will receive regular check-ups, eye examinations, and blood tests.

At a glance

Status

Authorised

Phase

Therapeutic exploratory (Phase II)

Sponsor

Polish Myeloma Consortium

Enrolment target

228

Start

13 Jul 2026

Relapsed/refractory Multiple myeloma

What is this study about?

Multiple myeloma is a cancer of the plasma cells, which are white blood cells found in the bone marrow. Although treatments have improved greatly in recent years, the cancer often returns after a period of remission, or it can become resistant to medicines that previously worked well. When this happens, doctors need new, effective options to keep the disease at bay.

This study tests a treatment plan that combines three medicines: belantamab mafodotin, pomalidomide, and dexamethasone. Belantamab mafodotin works by attaching to a specific protein on myeloma cells to deliver a cancer-killing medicine directly inside them. However, it is known to cause side effects affecting the front of the eye (the cornea), which can lead to dry eyes, irritation, or blurry vision.

To address this, researchers are using sensitive tests to look for 'minimal residual disease'—tiny numbers of cancer cells that standard tests cannot see. If tests show that the cancer has cleared down to this very deep level, doctors want to see if they can safely reduce the dose of belantamab mafodotin.

The ultimate goal of this research is to discover whether a tailored, lower dose can protect patients' eyesight and improve their daily quality of life, without losing any of the treatment's cancer-fighting power.

Key takeaways

Tests a three-drug combination for multiple myeloma that has returned or stopped responding to past treatment.
Investigates whether lowering the dose of belantamab mafodotin can reduce eye-related side effects.
Uses sensitive tests (MRD) to track tiny traces of cancer and guide dosing decisions.
Requires frequent hospital appointments and specialist eye examinations to protect your vision.
Participation is entirely voluntary, and you can stop at any time without losing NHS care.

Who may be eligible?

This study is designed for adults aged 18 and older who have been diagnosed with multiple myeloma that has returned (relapsed) or stopped responding to previous treatments (refractory).

To take part, participants must be well enough to manage day-to-day activities and attend regular hospital visits. Because the trial drug can affect the eyes, participants will need to have their eyes checked before joining to make sure they do not have severe existing eye conditions that would make taking part unsafe.

People who have certain other serious health issues, uncontrolled medical conditions, or specific prior reactions to these medicines may not be able to join. Your hospital doctor can review your medical records to confirm if this trial matches your situation.

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 multiple myeloma that has returned or is no longer responding to treatment.
I am well enough to attend regular hospital clinics and undergo routine tests.
I am willing to have regular eye exams to monitor my vision.
I am willing to undergo bone marrow tests during the study to check treatment progress.

Answer every question to see your result.

What does participation involve?

If you join the trial, you will receive treatment in repeating cycles. You will take pomalidomide and dexamethasone as capsules or tablets at home, and receive belantamab mafodotin as an intravenous drip in the hospital clinic. Depending on your test results, your doctor may give you a standard dose or a reduced dose.

You will need to attend regular hospital appointments for check-ups, blood tests, and detailed eye exams with an eye specialist to carefully monitor your vision and eye health. At certain points (such as at 6, 12, and 18 months), you will have bone marrow tests to measure how deeply the cancer has responded. You will also be asked to complete short questionnaires about your symptoms and quality of life. The study lasts for several years to monitor how long the treatment keeps the cancer under control.

Potential risks and benefits

Taking part may help shrink or control your myeloma, and you will be very closely monitored by a team of blood and eye specialists. The findings may also help future patients receive gentler treatments. However, there is no guarantee the treatment will work for you. Potential risks include common cancer drug side effects like tiredness, low blood cell counts, and increased risk of infection. Belantamab mafodotin frequently causes eye irritation, dry eyes, or blurred vision, though these usually improve if the dose is paused or reduced. Taking part is completely voluntary, and you can leave the study at any time without your standard NHS care being 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
Poland

Common questions

What is relapsed or refractory multiple myeloma?

'Relapsed' means the myeloma has returned after a period of improvement. 'Refractory' means the cancer is no longer responding to the treatment you were previously receiving.

Why are regular eye checks needed during the study?

One of the study drugs, belantamab mafodotin, can cause changes to the surface of the eye. Regular checks by an eye specialist help spot and treat any irritation early before it causes significant vision problems.

What does 'MRD-guided' mean?

MRD stands for Minimal Residual Disease. It refers to very sensitive tests that look for tiny traces of cancer cells. In this trial, doctors use these test results to decide whether it is safe to lower your medicine dose.

Will I have to pay for the trial treatments?

No. In UK clinical trials, the study medicines and any extra tests required by the research protocol are provided free of charge.

Can I leave the trial if the side effects are too difficult?

Yes. You have the right to withdraw from the trial at any point, for any reason. Your medical team will discuss alternative treatment options with you to ensure your care continues.