Mesenchymal-Stromal-Cell Therapy Effective Long-Term for Crohn's Disease Perianal Fistulas

By Reuters Staff

July 30, 2019

NEW YORK (Reuters Health) - Most patients with Crohn's disease whose perianal fistulas close after allogeneic bone marrow-derived mesenchymal stromal cell (bmMSC) therapy remain fistula-free four years later, researchers from the Netherlands report.

Perianal fistulas occur in about 25% of patients with Crohn's disease. Even with combined biological and surgical therapies, only 37% of patients with complex perianal fistulas have long-term fistula closure.

In an earlier study, Dr. Andrea E. van der Meulen-de Jong from Leiden University Medical Center and colleagues demonstrated an 86% reduction in the number of draining fistulas in patients treated with 30 million bmMSCs.

In the current study, they evaluated the safety and efficacy of local bmMSC therapy at four years among 13 of the original 15 bmMSC-treated patients and three of the original six placebo-treated patients.

After 24 weeks, 67% of perianal fistulas treated with 10 million bmMSCs, 86% of perianal fistulas treated with 30 million bmMSCs, and 29% of perianal fistulas treated with 90 million bmMSCs were closed, compared with 33% of perianal fistulas in the placebo group.

At four years, 75% (3/4) of patients treated with 10 million bmMSCs, 100% (4/4) of patients treated with 30 million bmMSCs and 20% (1/5) of patients treated with 90 million bmMSCs had complete clinical fistula closure, the researchers report in the Journal of Crohn's and Colitis, online June 14.

None of the three patients in the placebo group experienced partial or complete fistula closure at four years.

Based on MRI evaluation after four years, the fistula tract improved in 67% (6/9) of bmMSC-treated patients, and no de novo fistulas were found.

Therapy with bmMSC was also associated with significantly lower clinical disease activity and improved quality of life at four years.

"We have shown that the efficacy of local bmMSC therapy for perianal Crohn's disease fistulas was maintained for up to 4 years after treatment," the researchers conclude. "More long-term safety data are needed from both clinical trials and daily clinical practice to fully appreciate all safety aspects concerning local bmMSC therapy."

Digest Science funded the original study.

Dr. van der Meulen-de Jong was unavailable for comments.


J Crohns Colitis 2019.