P465 One year endoscopic and histologic outcomes to tofacitinib therapy in refractory ulcerative colitis

Abstract

Abstract Background Long-term real-life data on the efficacy of the Janus kinase inhibitor tofacitinib in moderate-to-severe ulcerative colitis (UC) are limited. We here report efficacy of tofacitinib in refractory UC patients with an emphasis on endoscopic and histologic outcome. Methods Fifty-four consecutive UC patients (Mayo endoscopic sub-score ≥2) initiating tofacitinib in 2 tertiary IBD referral centres were prospectively included (Table 1). Almost all were refractory to both anti-TNF (96.4%) and vedolizumab (92.7%) and received tofacitinib in standard dosage. Steroid-free clinical remission was defined as partial Mayo score of ≤2 with no single sub-score >1 and without any steroid exposure at assessment. Biological remission was defined as faecal calprotectin <250mcg/g, endoscopic remission as Mayo endoscopic sub-score of 0, endoscopic improvement as Mayo endoscopic sub-score of ≤1, and histologic remission as Nancy histology index of 0. A combination of endoscopic and histologic remission was referred as mucosal healing. All outcomes were assessed at year 1. Non-responder imputation and last observation carried forward analysis were applied. Results Patients were followed for a median [IQR] of 91.7 [67.2–102.4] weeks, with an exposure to tofacitinib of 23.9 [14.6–51.6] weeks. By year one, 31.5% of patients were in steroid-free clinical remission (Figure 1). Biological remission was observed in 26.9% of patients. Endoscopic improvement, endoscopic remission, histologic remission and mucosal healing, were observed in 31.5%, 24.1%, 22.0% and 18.0% of patients, respectively. Multivariate analysis identified baseline Mayo endoscopic sub score (OR 0.03, p=0.03); endoscopic improvement by week 16 (OR 36.5, p=0.008) and disease extent (OR 0.11, p=0.05) as independent predictors for endoscopic remission at year 1. Patients with left-sided colitis or proctitis experienced higher endoscopic remission rates (33.3% and 25.0%) then patients with extensive colitis (10.5%, p=0.09; p=0.6). Ultimately, 61.1% of all patients discontinued tofacitinib therapy after a median of 15.9 [9.2–24.5] weeks, due to primary non-response (n=25), loss-of-response (n=6) or (serious) adverse events (n=2). Thirteen patients (24.1%) required colectomy. During follow-up, no venous thrombo-embolisms or cancers were observed. One patient had to be admitted at ICU due to several life-threatening opportunistic infections. Conclusion In this highly refractory cohort of UC patients, tofacitinib induced and maintained endoscopic and histologic remission in up to one quarter of patients. UC patients with moderate left-sided colitis and proctitis had a numeric higher likelihood for a sustained effect than patients with extensive colitis.