To Örebro University

Background: Randomised controlled trials may not correctly reflect clinical practice. We aimed to assess the clinical effectiveness of ustekinumab in a real-world cohort of patients with ulcerative colitis (UC).

Methods: This observational, multi-centre cohort study explored ustekinumab treated patients with UC from the Swedish inflammatory bowel disease register (SWIBREG), a nationwide quality register. Prospectively collected clinical data were extracted December 2020. The primary outcome was the 16-week ustekinumab continuation rate. Secondary outcomes included A) drug continuation rate at the end of follow-up, B) corticosteroid-free biochemical remission, defined as f-Calprotectin<250μg/g, and C) corticosteroid-free clinical remission per patient-reported Mayo score, i.e. a rectal bleeding subscore <1 and a stool frequency subscore ≤1 and not greater than baseline. Continuous data are presented as median and (interquartile range). Differences between baseline and follow-up visits were assessed by the Wilcoxon signed-rank test.

Results: In total, 145 patients were included and followed for a median period of 32 (19-56) weeks. Baseline characteristics are presented in Table 1. The drug continuation rate was 87% (126/145) at 16 weeks and 69% (100/145) at end of follow-up (Figure 1-2). Corticosteroid-free clinical and biochemical remission rates at follow-up visits are shown in Figure 3. The 6-point Mayo score decreased from 5 (3-6) at baseline to 2 (2-4) at 16 weeks (p<0.01) and to 3 (2-4) at last follow-up (p<0.01). F-calprotectin levels decreased from 779 (252-1530) μg/g to 246 (56-844) μg/g at week 16 (p=0.02) and to 142 (36-935) μg/g at last follow-up (p<0.01).

Conclusion: Ustekinumab was associated with clinical effectiveness in this nationwide real-world treatment refractory cohort.