Safety and effectiveness of adalimumab in the treatment of ulcerative colitis: results from a large-scale, prospective, multicenter, observational study

Background/Aims: Adalimumab has been shown to induce and maintain clinical remission in patients with moderate to severe ulcerative colitis (UC). However, no large-scale population-based studies have been performed in Japan. This study was conducted to evaluate the safety and effectiveness of adalimumab in clinical practice in Japanese patients with UC. Methods: In this 52-week, prospective, multicenter, single-cohort, noninterventional, observational, postmarketing surveillance study, patients with moderate to severe UC received an initial subcutaneous injection of adalimumab 160 mg, followed by 80 mg at 2 weeks, and then 40 mg every other week. Safety assessments were the incidence of adverse drug reactions (ADRs) and serious ADRs. Effectiveness assessments were clinical remission, corticosteroid-free remission, mucosal healing, and change in C-reactive protein (CRP) levels from baseline. Results: Of 1,593 registered patients, 1,523 (male, 57.6%; mean age, 41.8 years) and 1,241 patients were included in the safety and effectiveness populations, respectively. ADRs were reported in 18.1% and serious ADRs in 4.9% of patients. Clinical remission was achieved in 49.7% of patients at week 4, increasing to 74.4% at week 52. Corticosteroid-free remission rates increased over time, from 10.4% at week 4 to 53.1% at week 52. More than 60% of patients demonstrated mucosal healing at weeks 24 and 52. Mean CRP levels (mg/dL) decreased from 1.2 at baseline to 0.6 at week 4 and 0.3 at week 52. Conclusions: This large real-world study confirmed the safety and effectiveness of adalimumab in patients with UC in Japan. No new safety concerns were identified.