Efficacy of cx601 (darvadstrocel) for the treatment of perianal fistulizing Crohn's disease-Aprospective nationwide multicenter cohort study.

Abstract

The use of mesenchymal stem cells is considered anovel and promising therapeutic option for patients with perianal fistulizing Crohn's disease; however, data on its clinical application remain scarce. This multicenter nationwide study aimed to assess the clinical efficacy of mesenchymal stem cells in closing complex anal fistulas. In this study 14 Crohn's disease patients (3males, 11females) with complex anal fistulas treated in 3 tertiary hospitals in Austria were included between October 2018 and April 2021. Injection of 120 million allogeneic expanded adipose-derived mesenchymal stem cells (Cx601-darvadstrocel) was performed in each patient. Closure of the external fistula opening without secretion by external manual compression was defined as treatment success. The median age of the patient population at the time of surgery was 32years (range 26-53years) with amedian body mass index of 21.7 kg/m2 (range 16.7-26.6 kg/m2). Of the patients 12 (86%) received monoclonal antibodies (infliximab, adalimumab, ustekinumab, vedolizumab) at the time of surgery. The median number of complex fistulas was 1.4 (range 1-2), The median operative time was 20 min (range 6-50 min) with no perioperative complications. After amedian follow-up of 92weeks, we found successful fistula closure in 57.1% (n = 8) of treated patients. The perianal disease activity index did not improve significantly from initially 7 to amedian of 6 after 52weeks (p = 0.495). Darvadstrocel is asafe, minimally invasive surgical technique without significant perioperative complications. Clinical success can be expected in about half of the treated patients.