Improving Response to Immunotherapy

VIDEO | 01:47

Medical oncologist Paul Chapman explains how it may be possible to manipulate gut bacteria to improve how patients respond to immunotherapy. (January 2020)

Show transcript

This is Dr. Paul Chapman from Memorial Sloan Kettering Cancer Center. Here's something you might want to know: In a previous video, I told you about how the stool microbiome — the bacteria in our gut — may affect how we respond to cancer treatment. I told you how melanoma patients responding to immunotherapy had different gut bacteria than melanoma patients who did not respond.

Responders had more diversity, that is, more different types of bacteria, and had a higher level of some specific bacteria. That's why I recommend my patients not take over-the-counter probiotics. They do not contain the right bacteria, and they decrease bacterial diversity in the gut. There's an idea that if we can manipulate the gut microbiome, we can get patients to respond better to immunotherapy.

This idea is now being tested at several cancer centers, including here at MSK. Melanoma patients about to begin immunotherapy are eligible for this study. First, they'll get a week of antibiotics to clear their own gut bacteria, and then they will receive gut bacteria in the form of pills from normal healthy donors selected because their gut microbiome is enriched for what we think are beneficial bacterial species. Then the patients will get their immunotherapy. And using stool samples, we will see if the transfer of gut bacteria was successful and safe, and we will measure the immune response.

We're just beginning to understand how gut bacteria shape our immune system. And this trial is certain to be the first of many in which we try to change our gut microbiome to fight disease. More to come.