RESUMEN
BACKGROUND: The efficacy of ustekinumab and vedolizumab for treating complex perianal fistula in Crohn's disease has been barely studied. We aimed to assess treatment persistence, clinical remission, and safety of these drugs in this context. METHODS: Crohn's disease patients who had received ustekinumab or vedolizumab for the indication of active complex perianal fistula, were included. Clinical remission was defined according to Fistula Drainage Assessment Index (no drainage through the fistula upon gentle pressure) based on physicians' assessment. RESULTS: Of 155 patients, 136 received ustekinumab, and 35 vedolizumab (16 received both). Median follow-up for ustekinumab was 27 months. Among those on ustekinumab, 54 % achieved remission, and within this group, 27 % relapsed during follow-up. The incidence rate of relapse was 11 % per patient-year. Multivariate analysis found no variables associated with treatment discontinuation or relapse. Median follow-up time for patients receiving vedolizumab was 19 months. Remission was achieved in 46 % of the patients receiving vedolizumab, and among them, 20 % relapsed during follow-up. The incidence rate of relapse was 7 % per patient-year. Adverse events were mild in 6 % on ustekinumab and 8 % on vedolizumab. CONCLUSION: Ustekinumab and vedolizumab appear effective, achieving remission in around half of complex perianal fistula patients, with favorable safety profiles.