COBRA

COBRA investigates whether a different type of treatment could be a good option for people with early bladder cancer.

Status: In set up

COBRA investigates whether a different type of treatment could be a good option for people with early bladder cancer. 

Early bladder cancer can have a high risk of returning after surgery. People with a high risk of their cancer returning are given a course of BCG treatment, put directly into their bladder regularly for up to 3 years. People having BCG treatment can have a lot of side effects which can stop them completing a full course of treatment. 

COBRA investigates whether giving people a different type of treatment into the bladder, using existing chemotherapy drugs, works as well as BCG without causing as many side effects. Results will be used to improve treatment for people with bladder cancer in future.

Infographic explaining the COBRA trial: BCG has been used to treat early bladder cancer for over 40 years and is put inside the bladder to stimulate the immune system to attack cancer cells. BCG can cause side effects which stop people from having a full course of treatment. Gem-Doce, two chemotherapy drugs, has been used in the bladder to treat early bladder cancer in the USA. The COBRA study will include 520 people from the UK with early bladder cancer. It will investigate whether Gem-Doce works as well as BCG to prevent cancer returning, with fewer side effects.

Image: COBRA infographic. BCG has been used to treat early bladder cancer for over 40 years and is put inside the bladder to stimulate the immune system to attack cancer cells. BCG can cause side effects which stop people from having a full course of treatment. Gem-Doce, two chemotherapy drugs, has been used in the bladder to treat early bladder cancer in the USA. The COBRA study will include 520 people from the UK with early bladder cancer. It will investigate whether Gem-Doce works as well as BCG to prevent cancer returning, with fewer side effects.

Who is included in the study?

COBRA includes people with early bladder cancer. Everyone who joins the trial will have had surgery to remove their cancer. If surgical samples show their cancer has high risk of returning, and they would normally receive BCG as a further treatment, they may join the trial. Up to 520 people will be included from NHS hospitals across the UK.

What are the study treatments?

Everyone who joins COBRA will be in one of two treatment groups:

  • Standard BCG treatment given into the bladder regularly over two years
  • Gem-Doce treatment given into the bladder regularly over two years

Participants will have regular check-ups during and after their treatment and we will collect information about how they are getting on until the study is completed.

Further information for participants 

Patient information sheet

A detailed summary is available on Cancer Research UK’s website. 

Our team are unable to offer any medical advice. If you are interested in finding out more about the trial or the treatments involved, please talk to your hospital doctor or GP about whether they may be a suitable option for you.

Further information for healthcare professionals

Protocol

Contact details and regulatory information

Chief Investigator: Professor Rakesh Heer, Imperial College London

Study Chair: Mr Wei Shen Tan, Yale School of Medicine

ICR-CTSU methodology lead: Professor Emma Hall

Trial management contact: [email protected]

Sponsor: The Institute of Cancer Research

Funding: National Institute for Health and Care Research: Health Technology Assessment NIHR160459

Trial identifiers

REC reference: TBA

CPMS ID: 57987

ISRCTN registry: TBA

Publications and presentations

There have been no presentations or publications to date.

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