Safety and effectiveness of carotegrast methyl in patients with ulcerative colitis: an interim report of post-marketing surveillance in Japan.

Background: The first multicenter, prospective post-marketing surveillance (PMS) in Japan was conducted to confirm the safety and effectiveness of carotegrast methyl (hereafter referred to as carotegrast) in the routine clinical practice for ulcerative colitis (UC) in Japan. Here, we report the results of the interim analysis of PMS. Methods: The ongoing PMS was initiated in June 2022 and will be continued until May 2028. Study patients are individuals with moderately active UC who were refractory or intolerant to 5-aminosalicylic acid, and who started carotegrast therapy for the first time. An interim analysis was conducted based on the data cut-off (March 27, 2025). Results: Safety and effectiveness analysis sets included 296 and 290 patients, respectively. In the safety analysis set, 36.8% of patients received carotegrast for <8 weeks and 63.2% for ≥8 weeks. The most common reason for treatment discontinuation was inadequate effectiveness in 44.0% of patients who received carotegrast for <8 weeks, and symptom improvement in 66.8% for ≥8 weeks. Adverse drug reactions (ADRs) were reported in 25 patients (8.45%). No serious ADRs, ADRs relevant to progressive multifocal leukoencephalopathy, and central nervous system-related ADRs were reported. No pregnancies were reported. One patient (0.34%) experienced an ADR of pyelonephritis related to infections. The proportions of patients with clinical response, clinical remission and rectal bleeding disappearance (defined by using partial Mayo score) were 146/185 (78.9%), 133/189 (70.4%) and 137/190 (72.1%) after 8 weeks carotegrast administration, respectively. Conclusions: No new safety and effectiveness concerns were identified in the interim analysis for PMS.