Objectives: Local mesenchymal stem cell (MSC) therapy for perianal fistulas in Crohn's disease (CD) has yielded promising results, but it still remains controversial. In this study, we aimed to conduct a meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy and safety of MSC therapy for perianal CD (pCD).
Methods: RCTs reporting MSC therapy for perianal fistulas in CD were searched and included. The effectiveness and safety data were analyzed using RevMan 5.3.
Results: A total of 7 RCTs were included in this meta-analysis. The analysis showed that patients receiving MSC therapy presented a higher healing rate (HR) of pCD than those in the control group (odds ratio (OR)=1.42; 95% confidence interval (CI) 1.18, 1.71; P=0.0002). Compared with placebo (saline solution), MSC therapy improved the HR of pCD (OR=1.85; 95% CI 1.32, 2.60; P=0.0004). MSC therapy showed significant long-term efficacy (OR=1.36; P=0.009; 95% CI 1.08, 1.71). When MRI was used to evaluate fistula healing, a pooled analysis showed that the MSC group achieved a higher HR than the control group (OR=1.95; 95% CI 1.33, 2.87; P=0.0007). Allogeneic MSC therapy was superior to the control treatment in improving HR (OR = 1.97; 95% CI 1.40, 2.75; P<0.001). Furthermore, no significant differences were observed between MSC therapy and placebo in terms of adverse events (AEs) (OR = 1.16; 95% CI 0.76, 1.76; P = 0.48). None of the AEs were judged to be related to MSC treatment.
Conclusions: This meta-analysis of RCTs provided evidence that local MSC injection is safe and efficacious for perianal fistulas in CD. In addition, this treatment has favorable long-term efficacy and safety profiles.