Brachytherapy + Nivolumab for Rectal Cancer

(IMPERIA Trial)

This trial tests a new approach to treating rectal cancer by using internal radiation therapy (brachytherapy) followed by doses of the immunotherapy drug Nivolumab before surgery. The goal is to determine if this combination is safe and effective in shrinking the cancer before surgical removal. Suitable candidates for this trial have been diagnosed with rectal cancer, show no signs of cancer spreading, and plan to undergo surgery to remove the tumor. As a Phase 2 trial, this research focuses on measuring the treatment's effectiveness in an initial, smaller group of participants.

Research has shown that high-dose-rate endorectal brachytherapy (HDREBT) is safe and generally well-tolerated for treating rectal cancer. Studies have found that patients receiving this type of internal radiation usually do not experience severe side effects. This treatment often precedes surgery to help shrink the tumor.

Nivolumab, an immunotherapy drug approved by the FDA for other types of cancer, is generally considered safe. However, some patients might experience side effects like tiredness, skin rash, and muscle pain. Serious side effects, such as inflammation of the heart or intestines, are rare.

Unlike the standard treatments for rectal cancer, which often involve chemotherapy and radiation, this new approach combines brachytherapy and nivolumab. Brachytherapy, known as HDRBET, delivers a concentrated dose of radiation directly to the tumor, which can be more precise and potentially less damaging to surrounding tissues. Nivolumab, an immunotherapy drug, works by boosting the immune system to attack cancer cells, offering a different mechanism of action compared to traditional chemotherapy. Researchers are excited because this combination could enhance treatment effectiveness and reduce side effects, potentially leading to better outcomes for patients.

This trial will evaluate the combination of high-dose-rate brachytherapy (HDRBET) followed by nivolumab and total mesorectal excision for rectal cancer. Research has shown that HDRBET effectively treats rectal cancer, with studies indicating that patients receiving HDRBET before surgery have about a 68% chance of surviving for five years. This treatment also helps shrink tumors, potentially making surgery easier.