Stem cells isolated from the fat of patients with Crohn’s disease, an inflammatory disease of the bowel, relieved them from fistulas, which are a common, and potentially dangerous side effect of the disease. This is according to the results of a phase 2 clinical trial published in the latest issue of STEM CELLS Translational Medicine (SCTM).
Patients with Crohn’s disease suffer from a painful, chronic disease in which the body’s immune system attacks its own gastrointestinal tract. In Crohn’s patients, inflammation within the bowel can sometimes extend completely through the intestinal wall and create a what is known as a “fistula.”. Fistulas are abnormal connections between the intestine and another organ or even the skin. If left untreated, a fistula can become infected and form an abscess that can be life threatening.
Chang Sik Yu, M.D., Ph.D., of the Asan Medical Center in Seoul, Korea, who is a senior author of the SCTM paper, describes the results of a clinical trial that was conducted in collaboration with four other hospitals in South Korea. According to Dr. Yu: “Crohn’s fistula is one of the most distressing diseases as it decreases patient’s quality of life and frequently recurs. It has been reported to occur in up to 38 percent of Crohn’s patients and over the course of the disease, 10 to 18 percent of them must undergo a proctectomy, which is a surgical procedure to remove the rectum.”
Overall, the treatments currently available for Crohn’s fistula remain unsatisfactory because they fail to achieve complete closure, lower recurrence of the fistulas and do not limit adverse effects, Dr. Yu said. Given the challenges and unmet medical needs in Crohn’s fistula, attention has turned to stem cell therapy as a possible treatment.
Several studies, including those undertaken by Dr. Yu’s team, have shown that mesenchymal stem cells (MSCs) do indeed improve Crohn’s disease and Crohn’s fistula. Their phase II trial enrolled 43 patients for a term of one year, over the period from January 2010 to August 2012. These patients received injections of their own fat-based MSCs, and 82 percent of them experienced complete closure of fistula eight weeks after the final ASC injection. 75 percent of the trial participants remained fistula-free two years later.
“It strongly demonstrated MSCs derived from ASCs are a safe and useful therapeutic tool for the treatment of Crohn’s fistula,” Dr. Yu said.
The latest study was intended to evaluate the long-term outcome by following 41 of the original 43 patients for yet another year. Dr. Yu reported, “Our long-term follow-up found that one or two doses of autologous ASC therapy achieved complete closure of the fistulas in 75 percent of the patients at 24 months, and sustainable safety and efficacy of initial response in 83 percent. No adverse events related to ASC administration were observed. Furthermore, complete closure after initial treatment was well sustained.”
“These results strongly suggest that autologous ASCs may be a novel treatment option for Crohn’s fistulae,” he said.
“Stem cells derived from fat tissue are known to regulate the immune response, which may explain these successful long-term results treating Crohn’s fistulae with a high risk of recurrence,” said Anthony Atala, M.D., Editor-in-Chief of STEM CELLS Translational Medicine and director of the Wake Forest Institute for Regenerative Medicine.