Real-life effectiveness of allogeneic expanded adipose-derived mesenchymal stem cell therapy for perianal fistulizing refractory Crohn's disease

Background: Real life data about the long-term efficacy of darvadstrocel for treating perianal fistulas in Crohn's disease (CD) remain scarce. Aim: To report the effectiveness and safety of darvadstrocel therapy to close perianal fistula in a real-life cohort of CD patients. Methods: All patients with CD suffering complex draining perianal fistulas who consecutively underwent administration of a single local injection of darvadstrocel at two centres were followed up and evaluated. The primary endpoint was clinical remission (closure of all external openings with no discharge at pressure) at week 24. Combined remission (defined as clinically plus MRI-assessed fistula closure) were also assessed at week 24 and 52. Results: A total of 36 CD patients (19 Male, mean age 38.5 years) were included with a median follow up of 16 months. Clinical remission was achieved in 17 out of 36 patients (47.2 %) and combined remission in 15 out of 36 patients (41.6 %) at week 24. At week 52, clinical and combined remission was achieved in 17 out of 36 patients (47.2 %) and in 15 out of 33 evaluable patients (45.4 %), respectively. Conclusion: In this real-world setting, a successful response to darvadstrocel therapy based on clinical remission was reported in around half of the patients and combined remission including radiological assessment in more than 4 out of 10 patients.