Patients with the most common type of colorectal tumors, known as MSS mCRC, had consistent responses to immunotherapy. In fact, 61% of these patients saw their tumor shrink or remain stable after receiving treatment.
Results from a new trial indicate that immunotherapy could successfully be used to treat the most common form of colorectal cancer, also known as bowel cancer. The findings of the new study, a phase 1 trial, show that patients with the most common type of colorectal tumors, known as MSS mCRC, had consistent responses to immunotherapy. In fact, 61% of these patients saw their tumor shrink or remain stable after receiving treatment.A study on immunotherapy drugs botensilimab and balstilimab has been published in the journal Nature Medicine. This is the first time that consistent and long-lasting responses to immunotherapy have been seen in hard-to-treat patients. The study, co-authored by Professor Justin Stebbing of Anglia Ruskin University (ARU), focused on MSS mCRC, the most common type of colorectal tumors, also known as microsatellite stable metastatic colorectal cancer. The results have been described as potentially game-changing and could have a major impact on the treatment of this type of cancer. Previous research has shown that immunotherapy can be effective in patients with specific mismatch repair deficiencies.Only a small percentage of colorectal cancer patients have deficient DNA mismatch repair (dMMR) tumours, and immunotherapy has not been effective for the more common MSS mCRC tumours. A new study in the United States used the immunotherapy drug botensilimab in combination with balstilimab on a group of patients. These drugs are monoclonal antibodies that stimulate the body’s immune system to attack the cancer. In a phase 1 trial, 101 patients participated in a six-month follow-up, and 61% of them saw their tumour shrink or remain stable after receiving a combination of boten.silimab (BOT) and balstilimab (BAL) are two drugs that were studied by Justin Stebbing, a Professor of Biomedical Sciences at Anglia Ruskin University in England. The study found that the most common side effects of these drugs, also known as treatment-related adverse events, were diarrhea and fatigue. According to Stebbing, these results are very exciting because it is the first time there has been convincing evidence that immunotherapy can work in all forms of colorectal tumors. This could potentially be a game-changing discovery, especially since colorectal or bowel cancer is one of the most common forms of cancer worldwide. The study is now moving into later phase clinical trials, and there is hope for its success.The approval for its use in the United States by the FDA is expected very soon. Given the significance of this issue and its impact on numerous people, we are hopeful that authorities in the UK will also act swiftly.
Dr Andrea Bullock, Assistant Professor in Medicine at Beth Israel Deaconess Medical Center and joint first author of the study, stated: “This research highlights the potential of the BOT/BAL combination in treating microsatellite stable metastatic colorectal cancer, the most prevalent form of colorectal cancer that has traditionally shown no response to immunotherapy. We believe that our findings will provide new hope for those who have been diagnosed.”
Dr Anthony El-Khoueir, joint last author, also added Dr. Y, Associate Director of Clinical Research and Chief of Section of Developmental Therapeutics at the USC Norris Comprehensive Cancer Center, stated that the phase 1 study of botensilimab shows promising anti-tumour activity, particularly in immunologically cold tumours like MSS colorectal cancer. The effectiveness observed demonstrates the potential of botensilimab in engaging anti-tumour immunity on a broader scale.
