MRI Data in Phase 3 Study Shows Potential Impact of IL-23 Inhibitor for Treating Perianal Fistulizing Crohn’s Disease

New research incorporating MRI findings demonstrates the potential utility of the IL-23 inhibitor guselkumab in treating patients with perianal fistulizing Crohn’s disease.

For the randomized phase 3 FUZION study, which was presented at the Digestive Disease Week (DDW) conference, researchers evaluated the impact of guselkumab (Tremfya, Johnson and Johnson) in 286 adult patients (mean age of 36.5) with > 1 active draining perianal fistula. All patients had previously failed therapies including oral corticosteroids, azathioprine, and methotrexate, or up to two advanced therapy classes, according to the study.^1,2

The study authors compared two different regimens of guselkumab with 113 patients being treated with subcutaneous injection of the agent at 100 mg every eight weeks while 115 patients received 200 mg of guselkumab every four weeks. There were 58 patients in the placebo group, according to the study.¹

At week 24, the researchers assessed the ability of the therapy regimens to achieve combined fistula remission, which was defined as complete closure of external openings without new fistula or abscess development or drainage by external openings; and the absence of > 2 cm fluid collections on MRI.¹

The study authors found that 28.3 percent of patients treated with 100 mg of guselkumab every eight weeks had combined fistula remission at 24 weeks in comparison to 27 percent of the cohort who received 200 mg of guselkumab every four weeks, and 10.3 percent in the placebo group.^1,2

"The pain, swelling and persistent drainage associated with perianal fistulizing Crohn's disease can be profoundly disruptive to patients' daily lives," said lead study author Laurent Peyrin-Biroulet, MD, PhD, head of the Inflammatory Bowel Disease Unit at the Department of Gastroenterology at Nancy University Hospital in Lorraine, France.

“Achieving durable fistula closure without repeated surgical interventions remains a significant unmet need. The results from the FUZION study demonstrate the ability of Tremfya to achieve combined fistula remission, which is an exciting step forward for patients, expanding what's possible for managing this debilitating and chronic condition."²

References

1. Peyrin-Biroluet L, Jairath V, Hart A, et al. Guselkumab for perianal fistulizing Crohn’s disease: week 24 results from the phase 3, randomized, double-blind, placebo-controlled, multicenter FUZION study. Presented at the Digestive Disease Week (DDW) conference, May 2-5, 2026, Chicago. https://ddw.org/

2. Johnson and Johnson. Johnson & Johnson study shows TREMFYA (guselkumab) is the first and only IL-23 inhibitor to demonstrate efficacy in perianal fistulizing Crohn’s disease. PR Newswire. Available at: https://www.prnewswire.com/news-releases/johnson--johnson-study-shows-tremfya-guselkumab-is-the-first-and-only-il-23-inhibitor-to-demonstrate-efficacy-in-perianal-fistulizing-crohns-disease-302760610.html . Published May 5, 2026. Accessed May 5, 2026.