Introduction

The therapeutic landscape for ulcerative colitis (UC) is rapidly evolving, with an increasing number of biologic agents available.

Aims & Methods

This systematic review and meta-analysis synthesised randomised controlled trials (RCTs) data on biologic therapies for achieving key endoscopic and histologic endpoints in moderate to severe UC. A systematic search of MEDLINE, EMBASE, Cochrane Library, Web of Science and grey literature was conducted through November 2024. Separate meta-analyses were performed for induction and maintenance. A random-effects model was used to estimate relative risks (RR), with 95% confidence intervals (CI) and confidence in estimates was evaluated with the GRADE approach (Grading of Recommendation Assessment, Development and Evaluation).

Results

We included 40 RCTs (13 therapies , 14,369 patients). Thirty-two trials provided data in induction phase and twenty-eight in maintenance phase. During induction phase, all biologic therapies except for mirikizumab and filgotinib 100 mg demonstrated superiority over placebo (RR 2.02, 95% CI:1.76–2.31, I²=72%) for endoscopic improvement. Upadacitinib showed the highest efficacy (RR 5.53, 95% CI: 3.78-8.09). In biologic-naive patients and in patients with no previous biologic failure status upadacitinib 30mg had the highest efficacy (RR 4.07, 95% CI:2.69-6.16). In biologic-exposed patients or those with previous biologic failure, upadacitinib 30mg also showed the greatest benefit (RR 10.52, 95% CI:4.55-24.34). For induction of mucosal healing, all interventions were superior to placebo (RR 2.95, 95% CI:2.11–4.13,I²=61%), except for filgotinib 100 mg. Risankizumab showed the highest efficacy (RR 10.25, 95% CI:2.49-42.11). In maintenance phase, all therapies showed superiority over placebo for endoscopic improvement. Upadacitinib showed the highest efficacy (RR 4.18, 95% CI: 2.79–6.27). In biologic-naïve patients or those without prior biologic failure, all interventions—except filgotinib 100 mg and vedolizumab—were significantly superior to placebo, with etrasimod showing the highest efficacy (RR 3.12, 95% CI: 1.79–5.43). Among biologic-exposed patients or those with prior biologic failure, upadacitinib, mirikizumab, ustekinumab, etrasimod, tofacitinib, and risankizumab 180 mg were significantly superior to placebo. Upadacitinib showed the highest efficacy (RR 7.58, 95% CI: 3.42–16.8). For mucosal healing all therapies were superior to placebo, except for risankizumab. Upadacitinib showed the highest efficacy (RR 4.01 ,95% CI: 1.81–8.87). In biologic-naïve patients or those without prior biologic failure, only etrasimod, mirikizumab, upadacitinib 30 mg and subcutaneous infliximab were significantly superior to placebo, with upadacitinib showing the highest efficacy (RR 3.02, 95% CI: 1.18–7.71). Among biologic-exposed patients or those with prior biologic failure, only etrasimod, mirikizumab, and upadacitinib were significantly superior to placebo, with etrasimod demonstrating the highest efficacy (RR 9.45, 95% CI: 1.31–68.36).

Conclusion

Biologic and small-molecule therapies demonstrated substantial efficacy in achieving key endoscopic and histologic endpoints in moderate to severe UC. Upadacitinib consistently showed the highest efficacy across both induction and maintenance phases. Stratified analyses revealed enhanced response rates in biologic-naïve patients, supporting early initiation of advanced therapies. Our findings highlight the importance of individualised treatment strategies and the urgent need for standardised endpoint definitions to enhance comparability across future trials.