RecruitingPhase IIIInterventional

Is Gem-Doce an alternative to BCG treatment for people with early bladder cancer?

The COBRA study is looking into a new treatment called Gem-Doce for people with early bladder cancer. The current standard treatment, BCG, can cause uncomfortable side effects, and some people can't finish it or find their cancer still returns. This study aims to find out if Gem-Doce is as good as BCG at stopping bladder cancer from coming back, but with fewer or milder side effects. Researchers will also look at how these treatments affect quality of life and their costs. Adults over 18 with recent early bladder cancer who would normally get BCG might be asked to join. Participants will receive either BCG or Gem-Doce directly into the bladder over two years and will have regular check-ups for five years.

At a glance

Status

Recruiting

Phase

Phase III

Sponsor

Institute of Cancer Research

Enrolment target

520

Start

01 Aug 2025

Estimated completion

31 Jul 2029

High-risk non-muscle invasive bladder cancer

What is this study about?

The COBRA study is investigating a new treatment named Gem-Doce for people who have early bladder cancer. Currently, the most common treatment for this type of cancer is called BCG. While BCG has been used successfully for many years, it often leads to uncomfortable side effects such as pain in the bladder or flu-like symptoms. These side effects can be so troublesome that some patients don't complete their full course of treatment. Even for those who do finish BCG, the cancer can sometimes come back, or, in some cases, get worse.

Because of these challenges with BCG, researchers are keen to find an alternative that is just as effective but ideally has fewer side effects. The main goal of the COBRA study is to discover if Gem-Doce can prevent bladder cancer from returning as well as BCG does, but with an improved experience for patients. The study will also carefully check how each treatment affects a person's general well-being and daily life, looking at what doctors call 'quality of life'. On top of that, they will compare the costs associated with both treatment options.

This is an important study because finding a treatment that is both effective and causes fewer side effects could significantly improve the care for people with early bladder cancer. It could mean less discomfort during treatment and potentially a better quality of life while still ensuring the best chance of keeping the cancer away.

Key takeaways

The study compares a new treatment (Gem-Doce) with the standard treatment (BCG) for early bladder cancer.
It aims to find out if Gem-Doce has fewer side effects while being just as effective as BCG.
Participants will receive treatment directly into the bladder over two years.
Follow-up check-ups will continue for five years in total.
Taking part helps advance bladder cancer treatment for the future.
You can stop participating at any time.

Who may be eligible?

You might be able to take part in this study if you are 18 years or older and have recently been diagnosed with a type of early bladder cancer that is usually treated with BCG. This mostly includes bladder cancer that hasn't spread into the muscle wall of the bladder and is considered 'high-risk', such as certain types of T1, Ta, or CIS bladder cancer. You would also need to have had any cancerous growths completely removed from your bladder, and be prepared to use effective birth control if needed.

There are also some reasons why you wouldn't be able to join. For example, if you've had bladder cancer before, or if your cancer is a very rare type of bladder cancer. You also can't take part if you have certain other medical conditions or are taking specific medications that might interfere with the treatments. If you are pregnant or breastfeeding, or have certain active infections like HIV or Hepatitis, you wouldn't be eligible. Your doctor will carefully check all these details to see if the study 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.

Are you 18 years or older?
Have you recently been diagnosed with high-risk early bladder cancer?
Has the cancerous tissue been completely removed from your bladder?
Do you not have a history of bladder cancer before this recent diagnosis?
Are you generally well enough for standard treatments?
Are you able to attend regular hospital visits for treatment over two years?

Answer every question to see your result.

What does participation involve?

If you decide to join the study, you'll be randomly assigned to receive one of two treatments: either the usual BCG treatment or the new Gem-Doce treatment. Both treatments are given directly into your bladder during hospital visits. You'll receive these treatments over two years. Following this, you will have regular check-ups for a total of five years, just as you would if you weren't in the study. You might also be asked to complete some optional questionnaires about your quality of life and how often you use healthcare. These questions are about how you're feeling and how the treatment affects your daily life. There will also be a short, optional and confidential survey about your general background information.

Potential risks and benefits

Taking part in this study could offer several potential benefits. For example, by exploring new treatments, you'd be helping researchers find potentially better ways to treat bladder cancer in the future, which could benefit many others. Gem-Doce, the new treatment, might cause fewer side effects than the standard BCG treatment. However, it's important to know that both treatments can cause some discomfort, such as pain when you pass urine or flu-like feelings. Serious side effects are rare for both treatments. You will receive all the necessary information and have plenty of time to consider whether to participate before making your decision. If you are in the Gem-Doce group, you will have seven more hospital visits for your treatment over the two years, but any travel costs for these extra visits will be paid back to you. Remember, you are free to withdraw from the study at any time, for any reason.

Locations (1)

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

Not provided at time of registration
Unverified
United Kingdom

Common questions

What is the main goal of the COBRA study?

The main goal is to find out if a new treatment called Gem-Doce is as effective as the standard BCG for early bladder cancer, but with fewer or milder side effects.

Will I know which treatment I'm getting?

No, you will be randomly assigned to either the BCG or Gem-Doce treatment group. This helps ensure the study results are fair and unbiased.

How long will I be involved in the study?

You'll receive treatment over two years, and then have regular check-ups for a total of five years.

Can I stop participating if I change my mind?

Yes, you are free to withdraw from the study at any time, for any reason, without it affecting your future medical care.

Who is paying for this research?

The study is funded by the National Institute for Health and Care Research (NIHR) in the UK.

How to find out more

Steven Penegar

cobra-icrctsu@icr.ac.uk +44 20 87224238 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.