Stem cells in bioabsorbable matrix promising therapy for perianal fistulas

Last Updated: 2017-04-24

By Will Boggs MD

NEW YORK (Reuters Health) - Autologous mesenchymal stem cells (MSCs) incorporated into a bioabsorbable matrix appear to foster healing of perianal fistulas in patients with Crohn's disease, according to a phase 1 study.

"To me the most surprising findings in this study have to do with the response in even the most refractory patients,” Dr. Allan B. Dietz from Mayo Clinic in Rochester, Minnesota, told Reuters Health by email. “The fact that patients had suffered years (and often more than a decade) prior to entering this study demonstrated to me that this is a new therapeutic paradigm.”

Perianal fistulas affect up to 20% of patients with Crohn's disease. A recent phase 3 trial demonstrated that injection of allogeneic MSCs into a fistula track appears safe and is associated with a 50% remission rate.

Dr. Dietz and colleagues developed an approach to deliver concentrated autologous MSCs to the fistula by attaching them to a bioabsorbable matrix; they tested the resulting plugs in 12 patients with persistent refractory perianal disease.

Nine patients experienced complete clinical healing by three months. By six months, 10 of 12 patients (83.3%) had complete clinical healing, the researchers report in Gastroenterology, online April 9.

MRI demonstrated significant decreases in the length of T2-weighted hyperintensity (median decrease, 22%) and nonsignificant decreases in the diameter (median decrease, 57%).

Van Assche perianal severity scores decreased significantly, without worsening in any patient.

“The future is promising using cellular-therapy techniques for this devastating complication,” co-author Dr. William A. Faubion, also at Mayo Clinic, told Reuters Health by email. “If the results are confirmed by the larger controlled phase 2 trial, I would expect MSC-matrix to be first-line therapy given the safety profile compared to current therapy (biologics).”

“This new approach (cells+matrix) does not fit into any of the previous categories of therapy (such as surgery, devices, biologics, or drugs),” Dr. Dietz added. “The approach was very safe and highly feasible, as every patient enrolled for treatment had a successfully manufactured product. While there is still much work to do, the very promising results justify significant effort to bring this new therapy to the many patients that suffer from this and other similarly devastating conditions.”

Dr. Dietz and co-author Greg Butler invented the technology used in this research, which has been licensed to Mill Creek LifeSciences, with which they and Mayo Clinic have royalty agreements.

SOURCE: http://bit.ly/2prKRNg

Gastroenterology 2017.