ABSTRACT Background/Aims The subcutaneous (SC) formulation of vedolizumab is available as an alternative to the intravenous (IV) formulation in patients with ulcerative colitis (UC). However, data from Asian patients are limited, and the clinical course of injection‐site reactions (ISRs) remains unclear. This study evaluated the efficacy and safety of switching from IV to SC vedolizumab in Japanese patients with UC, focusing on ISRs. Methods This retrospective study included patients who switched from IV to SC vedolizumab. The primary outcomes were the incidence and clinical course of ISRs. The secondary outcomes included adverse events other than ISRs, disease activity, remission rates, and treatment persistence. Results In total, 48 patients were included. The median fecal calprotectin levels remained stable from baseline to 12 months after switching (46.0 vs. 46.0 μg/g), with the fecal calprotectin remission rate remaining stable (41/45, 91% vs. 39/45, 87%). The persistence rate of SC vedolizumab was 98%, and the persistence rate without additional therapy was 94%. ISRs occurred in 29 patients (60%), most frequently within 3–6 months, with a median duration of 4 months. More than half of ISRs improved or resolved by 12 months, and only 11 patients (23%) experienced persistent ISRs. No adverse events other than ISRs were considered likely or probably related to SC vedolizumab. Conclusions In Asian patients with UC, disease activity was maintained after switching from IV to SC vedolizumab. Although ISRs were common after switching, most were self‐limiting. Therefore, switching back to IV formulation solely for ISR management should be cautiously considered.
Furuya et al. (Wed,) studied this question.