A clinical trial led by London-based scientists has found fecal transplants could improve treatment for people battling skin cancer.
The Phase I trial by Lawson Health Research Institute, the Centre hospitalier de l’Université de Montréal (CHUM), and the Jewish General Hospital (JGH) in Montreal is said to be a world-first.
Fecal transplants involve collecting stool from a healthy donor and then screening and preparing it in a lab before transplanting it into a patient. The goal is to use the donor's microbiome to get healthy bacteria in the patient's gut.
"The connection between the microbiome, the immune system, and cancer treatment is a growing field in science,” said Dr. Saman Maleki, Lawson scientist and senior study investigator. “This study aimed to harness microbes to improve outcomes for patients with melanoma.”
Researchers recruited 20 patients with advanced melanoma for the trial. They were administered approximately 40 fecal transplant capsules orally during a single session, one week before they started immunotherapy - a treatment that uses drugs to simulate a person's immune system to attack and destroy cancer.
The study determined that combining fecal transplants with immunotherapy is safe for patients. This was the primary objective of the phase I trial. However, scientists also found that of the patients who retained the donors' microbiome, 65 per cent responded to the combination treatment. Only five patients experienced adverse effects that led to treatment being discontinued.
“We have reached a plateau in treating melanoma with immunotherapy, but the microbiome has the potential to be a paradigm shift,” said Dr. Bertrand Routy, oncologist and director of CHUM’s Microbiome Center. “This study puts Canada at the forefront of microbiome research by showing we can safely improve patients’ response to immunotherapy through fecal transplants.”
Making this study particularly unique is the fact the transplants were administered in capsule form. This technique was pioneered in London by Lawson Scientist Dr. Michael Silverman.
"Our group has been doing fecal transplants for 20 years, initially finding success treating C. difficile infections. This has enabled us to refine our methods and provide an exceptionally high rate of the donor microbes surviving in the recipient’s gut with just a single dose,” said Silverman, who is also chair of Infectious Diseases at Schulich Medicine and medical director of the Infectious Disease Care Program at St. Joseph’s Health Care London. “Our data suggests at least some of the success we are seeing in melanoma patients is related to the efficacy of the capsules."
The results of the phase I clinical trial were published in the journal Nature Medicine.
Phase II of the trial is already underway and involves healthcare centres in Ontario and Quebec. Additionally, Lawson researchers are studying whether fecal transplants would improve treatment outcomes for other cancers including renal cell carcinoma, pancreatic cancer and lung cancer, as well as HIV and rheumatoid arthritis.
