Early stage research shows promise for bowel cancer immunotherapy drug

Results of a small clinical trial at Memorial Sloan Kettering Cancer Center (MSK) in New York has shown compelling early results for a potential new drug for treating bowel cancer patients.

Researchers investigated a drug called dostarlimab, which is a type of immunotherapy. Immunotherapy is a type of targeted treatment that helps your own immune system to destroy the cancer. There is lots of ongoing research looking into new immunotherapy drugs. Some patients may be able to have them by taking part in clinical trials. Immunotherapies don’t work for everyone.

Twelve months after completing their treatment, all patients in the US-based study showed no evidence of cancer. However it is important to note that although these are exciting results, this was a very small study, with only 12 patients. All patients had a specific type of locally advanced rectal cancer. This means the cancer had spread into the tissue surrounding the rectum.

During the trial, patients were all given immunotherapy alone, with no need for other treatments such as chemotherapy, radiotherapy or surgery. This means that they also had fewer side effects and less impact on their quality of life.

The research was focused on a specific group of these rectal cancer patients who all had changes (mutations) to specific genes called mismatch repair (MMR) genes. These genes usually help repair DNA. Bowel cancers that have changes to MMR genes often have a high number of mutated genes. This is referred to as deficient mismatch repair or MSI-high.

Genevieve Edwards, Chief Executive of Bowel Cancer UK, says: “Almost 43,000 people are diagnosed with bowel cancer every year in the UK, and while the study shows very promising results, it’s too early  to tell how this immunotherapy treatment could impact patients more widely. It’s important that future research includes a larger and more diverse group of patients, across different treatment centres and over a longer period of time. Immunotherapy doesn’t work for everyone, so a larger-scale study will help researchers determine whether this could be a real step forward for the future of bowel cancer treatment.”

• Read more about mismatch repair genes and immunotherapy

• Read a summary of the paper

• Find out more about the research projects we're currently funding

• Supporter, bowel cancer patient and GP Dr Anisha Patel gives her perspective on the new research