Dr. John Rioux and his team at the Montréal Heart Institute are developing ways to improve doctors’ ability to diagnose Crohn’s and colitis based on how a specific gene impacts gut inflammation.
For 20 years, Dr. Rioux has studied the IL23 gene, which regulates the activity of immune cells, and his groundbreaking work showed that some of its variants protect against Crohn’s and colitis. To date, this has opened the door to new therapies, such as a biologic drug, Skyrizi, that stops the inflammatory action of IL23. Skyrizi has been available for patients since 2019.
The long road to discoveries
Dr. Rioux’s journey started with help from research funding organizations, including Crohn’s and Colitis Canada since 2009.
“Funding from Crohn’s and Colitis Canada allowed my team to build capacity and apply for other major grants,” says Dr. Rioux. “This has let us to keep up our momentum and build our understanding of important mechanisms of how genetics influence Crohn’s and colitis. Crohn’s and Colitis Canada’s partnership and financial support has been key to our success.”
By leveraging funding from Crohn’s and Colitis Canada in 2009, Dr. Rioux was able to obtain $2.5 million in additional funding later. This gave his team the means to uncover which genes affect the immune system response and protect against Crohn’s disease.
An additional $10 million came in 2013. It contributed to the development of blood-based tools to better diagnose and treat people with Crohn’s or colitis. One study compared blood samples from 300 people with Crohn’s to 300 others in an international database Dr. Rioux helped establish in the early 2000s.
“Through this project, we identified an array of compounds in the blood that were strongly linked to Crohn’s, including six fatty acids,” says Dr. Rioux. “We were able to build a diagnostic model that can predict Crohn’s with 90% accuracy. Our current objective is to validate this model in clinics with the goal of delivering a tool that will speed up diagnosis and get patients the care they need as soon as possible.”
The next major development was in 2017 when Dr. Rioux was part of a team that undertook a $25 million project involving 75 researchers and thousands of patients across Canada. He and his team led DNA sequencing studies to identify causes of Crohn’s and colitis. The goal is to apply these findings to understanding an individual’s response to therapy that will lead to better disease management.
Since 2022, Dr. Rioux’s findings are contributing to the development of a diagnostic test for Crohn’s. His team looked at potential biological markers and built tests for each. They are now refining the ones that offer the best chance of success. Another application could be the development of tests to support decisions around the best treatments.
“It’s a long and difficult journey from scientific discovery to developing tools to help speed up Crohn’s and colitis diagnosis, and to find the most effective treatments for each patient. We’ve shown that it can be done, and we continue to do it,” Dr. Rioux says.