Evaluating the effects of 5‐aminosalicylic acid on tofacitinib treatment in ulcerative colitis

Abstract Background and Aim Tofacitinib and aminosalicylic acid (5‐ASA) are commonly used to treat ulcerative colitis (UC). However, evidence on the effect of concomitant 5‐ASA use in patients receiving tofacitinib is limited. This study investigated the effects of 5‐ASA combined with tofacitinib in UC patients. Methods This retrospective cohort study used data from the Medical Data Vision database, including patients with UC treated with tofacitinib from May 2018 to April 2022. Patients were grouped according to tofacitinib dosage and assessed for the efficacy of concomitant 5‐ASA use. The primary endpoint was clinical relapse. Results A total of 1213 patients with UC were included in the analysis, with 416 in the 5 mg BID group and 797 in the 10 mg BID group. In the 5 mg BID group, the cumulative relapse‐free rate was significantly higher in patients receiving concomitant 5‐ASA ( P < 0.0001). Multivariate Cox regression analysis confirmed that concomitant 5‐ASA use significantly reduced the risk of clinical relapse (adjusted hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.31–0.70). In the 10 mg BID group, no significant difference was noted in the cumulative relapse‐free rate between patients treated with and without 5‐ASA ( P = 0.445). Similarly, multivariate Cox regression analysis indicated that concomitant 5‐ASA use did not significantly affect relapse risk (adjusted HR, 0.97; 95% CI, 0.71–1.32). Conclusions Concomitant 5‐ASA use reduced the risk of relapse in patients on 5 mg tofacitinib BID, suggesting benefits at lower doses. However, no significant benefit was observed with 5‐ASA use in those 10 mg tofacitinib BID.