All patients treated for rectal cancer with an experimental immunotherapy drug went into remission, in findings that researchers have hailed as a breakthrough.
The 14 patients who were given the new drug, dostarlimab, were found to have no trace of cancer after six months. Researchers at the Sloan Kettering Memorial Cancer Center in New York City were unable to find any signs of the disease through physical examination, endoscopies, MRIs or other scans.
The researchers described the results, published in the New England Journal of Medicine, as “innovative discoveries” and said they were surprised by the universal success rate. “I think this is the first time this has happened in the history of cancer,” Dr. Luis Diaz, a prominent member of the team, told the New York Times.
For the patients involved, and potentially for other patients with specific types of rectal cancer coming after them, the result was spectacular. It allowed them to avoid further surgery, chemotherapy and radiation, proceeding only under observation.
This could have far-reaching implications, especially for young adults.
“Surgery and radiation have permanent effects on fertility, sexual health, bowel and bladder function, and the implications for quality of life are substantial, especially in those where standard treatment would affect the potential for having children. “said another principal investigator, Dr. Andrea Cercek. “As the incidence of rectal cancer increases in young adults, this approach can have a significant impact.”
Dostarlimab has been developed by the pharmaceutical company GlaxoSmithKline. The drug was given to patients every three to six months at a cost of $ 11,000 per dose.
The drug is known as a control point inhibitor. It works by removing the shield that cancer cells put around them and preventing T cells from the body’s immune system from attacking them.
Without the shield, cancer cells are exposed to the immune system and vulnerable to destruction.
The findings lie within one of the most promising areas of experimental frontier cancer research that combines personalized medicine with immunotherapy. The ambition is to train the immune system to destroy cancer cells by helping it detect specific mutations in the genetic constitution of a patient’s own tumor.
Sloan Kettering researchers designed the clinical trial to apply it to a specific subgroup of kidney cancer patients. All 14 patients had a rare mutation in their tumor cells known as “mismatch repair deficiency,” meaning the cells’ DNA repair system does not work.
As a result, cancer cells produce proteins with higher levels of genetic error, making them more visible to the body’s immune system once the shield has been removed.
Scientists involved in the dostarlimab trial are concerned about not presenting the findings as a cure. Patients will be kept under close medical evaluation to see how long they remain free of cancer.
But they are optimistic about these first results. Diaz said the new treatment would change the practice for people with the relevant type of rectal cancer.