AuthorisedHuman Pharmacology (Phase I)- OtherInterventional

OV-PRIME-R (Oncolytic Virotherapy to enhance PReoperative IMmunotherapy Efficacy in patients with proficient mismatch repair (pMMR) Rectal cancer

This early-stage study, called OV-PRIME-R, is looking into a new way to treat rectal cancer. Specifically, it's for patients whose cancer cells have a particular ability to repair their DNA, known as 'proficient mismatch repair'. The trial is testing a special virus designed to attack cancer cells. The main idea is to see if giving this virus before surgery can boost the effects of other treatments that use the body's own immune system to fight cancer. This is a very early trial, mainly focused on understanding how safe the treatment is and how it works in the body.

At a glance

Status

Authorised

Phase

Human Pharmacology (Phase I)- Other

Sponsor

Region Hovedstaden

Enrolment target

Start

23 Feb 2026

Rectal cancer with proficient mismatch repair (pMMR)

What is this study about?

You've been diagnosed with rectal cancer, and you might be wondering about all your treatment options. This particular study, called OV-PRIME-R, is aiming to find new and more effective ways to treat rectal cancer, especially for those whose cancer cells have a normal ability to repair their DNA – this is called 'proficient mismatch repair' (pMMR). While many trials focus on new drugs, this one is looking at something called 'oncolytic virotherapy'. This essentially means using a modified virus that's designed to infect and destroy cancer cells, while leaving healthy cells alone.

Now, here's where it gets interesting: the researchers believe this special virus might also make your own immune system better at fighting the cancer. The idea is that when the virus attacks cancer cells, it could make them more visible to your immune system, allowing other immune-boosting treatments to work more effectively. This study is testing if giving this virus before surgery, alongside existing immune therapies, can improve the overall treatment and outcomes for patients.

Because this is a very early study (called a Phase I trial), the main goals are to make sure the treatment is safe for people and to understand how it behaves in the body. It's about gathering important information before moving on to larger studies to see how well it works. The hope is that this approach could eventually lead to more powerful treatments for rectal cancer.

Key takeaways

This is an early-stage study testing a new virus-based treatment for rectal cancer.
It's for patients whose cancer cells have 'proficient mismatch repair' (pMMR).
The treatment aims to boost the immune system's fight against cancer before surgery.
The main goals are to check for safety and understand how the treatment works.
Participation involves close monitoring and regular visits to the study team.

Who may be eligible?

This study is for adults aged 18 or older who have been diagnosed with rectal cancer. A key requirement is that your cancer cells must have 'proficient mismatch repair' capacity. This is a specific feature of your cancer that your doctors will be able to check with tests.

To join, you would also need to be well enough generally to take part in a clinical trial. The study team will review your full medical history, current health, and other test results to make sure it's safe for you to participate. Both men and women are welcome to take part.

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?
Do you have rectal cancer?
Has your doctor confirmed your cancer has 'proficient mismatch repair' (pMMR)?
Are you generally well enough to consider joining a clinical study?

Answer every question to see your result.

What does participation involve?

If you decide to join the study, you'll work closely with a team of doctors and nurses. You'll likely have several visits to the hospital or clinic for assessments, which could include examinations, blood tests, and scans to monitor your health and how the treatment is working. You will receive the study treatment as part of your care. The specific details of how often you'll receive the treatment and have appointments will be explained by the study team, as will the total length of time you'll be involved with the study, including follow-up appointments after your main treatment period. You'll also need to follow specific instructions regarding any medication or advice given by the study team.

Potential risks and benefits

Taking part in a clinical trial offers potential benefits, such as gaining access to new treatments before they are widely available and contributing to medical knowledge that could help others in the future. However, there are also potential risks, including side effects from the experimental treatment that are not yet fully known, or the treatment not being effective for you. You will be closely monitored, and your safety is the research team's top priority. Remember, participating is always voluntary, and you have the right to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (1)

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

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Unverified
Denmark

Common questions

What does 'oncolytic virotherapy' mean?

It means using a special virus that's designed to attack and destroy cancer cells specifically, while leaving healthy cells alone.

What does 'proficient mismatch repair' (pMMR) mean for my cancer?

It's a technical term describing how your cancer cells are able to repair their DNA. Your doctor will know if your cancer has this feature.

Is this treatment available to everyone with rectal cancer?

No, this is an experimental treatment in a clinical trial, and it's currently only for patients who meet very specific criteria determined by the study.

Will I still have surgery if I join this study?

Yes, this study is looking at a new treatment given before surgery to enhance its effects, so surgery is still part of the plan.

What's the main goal of this early-stage trial?

The main goals of this Phase I trial are to check if the new treatment is safe for people and to understand how it works in the body.