AuthorisedTherapeutic confirmatory (Phase III)Interventional

C5701009 - A Phase 3, Open-label, Randomized Study To Evaluate Enfortumab Vedotin in Combination with Pembrolizumab in Adult participants with Muscle-Invasive Bladder Cancer Who Are Ineligible for or have elected not to undergo cystectomy

This phase 3 clinical trial is looking at a new drug combination for adults with muscle-invasive bladder cancer. This type of cancer has spread into the deep muscle wall of the bladder. The usual treatment often involves major surgery to remove the bladder, known as a cystectomy. However, some people are not well enough for this major operation, or they choose not to have it. This study is testing whether giving two medicines together—enfortumab vedotin (Padcev) and pembrolizumab (Keytruda)—can effectively fight the cancer without removing the bladder. Both medicines are given directly into a vein through a drip. Researchers want to find out if this combination can shrink the cancer, help people live longer, and prevent the cancer from returning, while carefully monitoring any side effects to check how safe the treatment is.

At a glance

Status

Authorised

Phase

Therapeutic confirmatory (Phase III)

Sponsor

Pfizer Inc.

Enrolment target

Start

15 Oct 2026

Muscle-Invasive Bladder Cancer

What is this study about?

Bladder cancer happens when abnormal cells grow in the lining of the bladder. In muscle-invasive bladder cancer, the tumour has grown deeper, spreading into the thick muscle wall. The standard care often involves an operation called a cystectomy, which removes the entire bladder. While this can be very effective, it is a major, life-changing procedure that is not suitable for everyone, particularly those with other serious health conditions, and some patients prefer to avoid it.

This clinical trial is exploring a different approach using two modern cancer treatments. Pembrolizumab is an immunotherapy, which works by helping your body's own immune system recognise and attack cancer cells. Enfortumab vedotin is a targeted therapy designed to attach directly to bladder cancer cells and deliver a medicine straight inside them to destroy them.

By combining these two drugs, researchers hope to offer an effective alternative to bladder surgery. The study aims to see whether this drug combination can clear the cancer, stop it from spreading to other parts of the body, and allow patients to keep their bladder for longer, while maintaining a good quality of life.

Key takeaways

Tests a combination of two targeted cancer drugs: enfortumab vedotin and pembrolizumab.
Aimed at adults with bladder cancer that has grown into the muscle layer.
Designed for people who cannot have or choose not to have surgery to remove their bladder.
Aims to control the cancer and help patients keep their bladder.
Participation is entirely voluntary and you can leave at any time.

Who may be eligible?

This trial is open to adults aged 18 and over who have been diagnosed with muscle-invasive bladder cancer. To take part, you must have cancer that has grown into the muscle layer of the bladder, but you are either not physically well enough to undergo major bladder removal surgery, or you have chosen not to have this operation after discussing your options with your doctor.

You will need to have reasonable overall health and fitness to receive the trial treatments safely. The study team will carry out detailed checks, including blood tests and scans, to confirm that your organs, like your kidneys and liver, are working well enough for the medications.

You may not be eligible if the cancer has already spread widely to distant parts of your body, if you have certain active autoimmune conditions, or if you have had specific cancer treatments very recently. Your hospital doctor or the study team can review your medical history to see if the trial is right for you.

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 muscle-invasive bladder cancer.
I am unable to have, or have chosen not to have, surgery to remove my bladder.
I am well enough to attend regular hospital appointments for treatment and tests.
I am willing to receive treatments through a drip into a vein.

Answer every question to see your result.

What does participation involve?

If you take part, you will receive the study medicines as an intravenous infusion (a drip into a vein) at a hospital clinic on set days every few weeks. Before you start, the medical team will carry out baseline tests, such as blood samples, urine tests, heart checks, and imaging scans (like CT or MRI scans), to measure the cancer and check your general health.

Throughout the study, you will have regular clinic appointments to receive your treatment and be monitored closely. The team will ask about any symptoms or side effects, repeat your blood tests, and schedule periodic scans to see how the cancer is responding.

Treatment usually continues for several months, provided the medicines are helping and you are not experiencing severe side effects. After your treatment ends, you will enter a follow-up period where the team will keep in touch to check on your long-term health and wellbeing.

Potential risks and benefits

The possible benefit of joining is that the study drugs might shrink or control your bladder cancer without the need to remove your bladder. However, there is no guarantee that the treatment will work for you. Like all cancer medications, both drugs can cause side effects. Common ones include tiredness, rash, nausea, nerve tingling in the hands or feet, changes in blood sugar, or inflammation caused by the immune system. The trial team will watch you very closely and treat any side effects promptly. Taking part is completely voluntary, and you can withdraw from the study at any time without it affecting your regular NHS care.

Locations (4)

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

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Unverified
France
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Unverified
Spain
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Unverified
Italy
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Unverified
Germany

Common questions

What does 'muscle-invasive' bladder cancer mean?

It means the cancer cells have grown past the inner lining of the bladder and into the deeper muscular wall, requiring more intensive treatment.

Do I have to pay to take part in this trial?

No. In the UK, clinical trial medicines and study-related tests are provided free of charge, and some trials may help cover travel expenses.

How are the trial medicines given?

Both medicines are liquid solutions given slowly through a drip into a vein, usually during outpatient visits at the hospital.

Can I leave the study if I change my mind?

Yes. You are free to stop taking part at any point, and your normal medical team will continue to look after you and discuss other treatment options.

Will I definitely receive the trial medicines?

This is an open-label trial evaluating this specific combination, but your trial doctor will explain the exact study design and what treatment you will receive before you agree to join.