Not yet recruitingPhase IIInterventional

A clinical trial testing a new treatment called mRNA-4194 for people with Lynch syndrome

This study is testing a new treatment called mRNA-4194 for individuals with Lynch syndrome. Lynch syndrome increases the risk of certain cancers, particularly bowel cancer. The treatment aims to stimulate the body's immune system to recognise and eliminate specific abnormal cells before they develop into cancer. It does this by providing temporary instructions for the body to produce harmless protein pieces found in these abnormal cells, effectively 'training' the immune system. The trial is looking for people aged 18 and over with Lynch syndrome. It involves receiving injections of mRNA-4194, alongside health checks, blood tests, and colonoscopies, to assess its safety and how well it activates the immune system.

At a glance

Status

Not yet recruiting

Phase

Phase II

Sponsor

University of Oxford

Enrolment target

110

Start

15 Jun 2026

Estimated completion

02 Feb 2029

Lynch syndrome (LS)

What is this study about?

This study is looking into a new treatment called mRNA-4194 for people who have a condition called Lynch syndrome. Lynch syndrome is a genetic condition where there's a fault in one of your genes. This fault means your body has a harder time fixing errors in your cells. Because of this, people with Lynch syndrome have a higher chance of developing certain types of cancer, most commonly in the bowel and, for women, the womb. Often, before bowel cancer develops, small growths called polyps can appear, which can be found and removed during a colonoscopy.

The mRNA-4194 treatment aims to give your immune system a helping hand. Your immune system is your body's natural defense against illness. This treatment tries to teach your immune system to recognise and get rid of those early abnormal cells – the ones that might turn into cancer – even before they become a problem. It works by giving your body temporary instructions to create small, harmless parts of proteins that are specific to these abnormal cells. This process is like a training exercise, helping your immune system learn to spot and destroy similar cells in the future.

This is a Phase II trial, meaning it's still in the earlier stages of testing in people. Researchers want to make sure the treatment is safe and to see if it can successfully train the immune system to fight off these abnormal cells. The hope is that this new approach could potentially prevent cancer from developing in individuals with Lynch syndrome, offering a new way to manage their condition.

Key takeaways

Tests new cancer prevention treatment (mRNA-4194) for Lynch syndrome.
Aims to train the immune system to destroy pre-cancerous cells.
Involves regular injections, blood tests, and colonoscopies.
Potential side effects include flu-like symptoms and injection site reactions.
Study will run from March 2026 to September 2029.
Run by University of Oxford and funded by Moderna.

Who may be eligible?

To be considered for this study, you need to be at least 18 years old. You must also have a confirmed diagnosis of Lynch syndrome, meaning a specialist genetic test has shown you carry a specific faulty gene linked to the condition.

For the second part of the study, there's an additional requirement: during a screening colonoscopy (a procedure to look at the inside of your bowel), you must have at least one small bowel polyp. These polyps need to be between 2mm and 10mm in size and look like the type that can sometimes become cancerous. If you have these polyps, you would need to agree that they can be left in place temporarily, with a plan for them to be removed later in the study.

Polyps smaller than 2mm or larger than 10mm, or those that don't look like the type of concern, would be removed during your screening colonoscopy and would mean you wouldn't be able to participate in this specific part of the study.

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 old or older?
Have you been diagnosed with Lynch syndrome by genetic testing?
Are you comfortable with receiving regular injections?
If joining Part 2, are you willing for small bowel polyps (2-10mm) to be temporarily left in place for monitoring?

Answer every question to see your result.

What does participation involve?

If you join this study, you will go through two main parts. In Part 1, up to 30 adults will receive several injections of mRNA-4194 into a muscle over 12 weeks. This helps researchers figure out a safe and effective dose. In Part 2, another 80-110 adults will receive several injections over six months, followed by a booster injection after a year. Throughout the study, you'll have regular appointments for health checks, blood samples, and colonoscopies to look for any changes in your bowel lining or detect polyps. These samples will be analysed by scientists to see if the treatment is successfully training your immune system. The study is expected to run from March 2026 to September 2029.

Potential risks and benefits

This is the first time mRNA-4194 has been given to people, so all side effects aren't fully known. However, based on similar treatments, you might experience flu-like symptoms such as tiredness, a mild fever, chills, headaches, and muscle or joint aches. You could also have soreness, swelling, or redness where the injection was given. Less commonly, more severe reactions at the injection site or even allergic reactions could occur. The main benefit of participating is helping doctors understand if mRNA-4194 is safe and if it can help your immune system prevent cancer in people with Lynch syndrome. Whilst polyps will be monitored closely, the study involves leaving some small polyps in place temporarily, which carries a small additional risk compared to standard care, although strict safety measures are in place to minimise this. You have the right to withdraw from the study at any time.

Locations (1)

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

Churchill Hospital
Unverified
Oxford, England

Common questions

What is Lynch syndrome?

Lynch syndrome is a genetic condition that increases your risk of certain cancers, especially bowel and womb cancer, because your body has trouble repairing damaged cells.

What exactly does mRNA-4194 do?

mRNA-4194 is a new treatment that aims to teach your immune system to find and destroy abnormal cells before they can turn into cancer, by showing it specific protein pieces related to these cells.

What are the common side effects expected?

Common side effects are expected to be flu-like symptoms (like tiredness, mild fever, body aches) and reactions at the injection site (soreness, swelling, redness).

Will I have to have a colonoscopy?

Yes, participants will have colonoscopies as part of the study to monitor for changes in their bowel and to detect polyps.

Where is the study taking place?

The study is being run from the University of Oxford in the UK, but will be conducted in hospitals that specialise in clinical trials.

How to find out more

OCTO INTERCEPT-Lynch Trial Team

octo-intercept-lynch@oncology.ox.ac.uk - Official trial record

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