Yamamoto Takanobu, Yoshida Soichiro, Maezawa Yuya, Tamiya Takashi, Toide Masahiro, Fukushima Hiroshi, Uehara Sho, Araki Saori, Ito Masaya, Kobayashi Shuichiro, Yoshinaga Atsushi, Kawamura Naoko, Takazawa Ryoji, Sakai Yasuyuki, Ootsuka Yukihiro, Tsukamoto Tetsuro, Nagahama Katsushi, Tanaka Hajime, Kitabayashi Ryo, Hanazawa Ryoichi, Ishiguro Megumi, Sato Hiroyuki, Koike Ryuji, Fujii Yasuhisa
Urology, Tokyo Metropolitan Tama-Nambu Chiiki Hospital, Tama, Tokyo, Japan.
Urology, Institute of Science Tokyo, Bunkyo, Tokyo, Japan
BMJ Open. 2025 Mar 24;15(3):e094230. doi: 10.1136/bmjopen-2024-094230.
Overactive bladder (OAB) is a condition characterised by urinary urgency, often accompanied by frequency and nocturia. Antimuscarinics and β3 receptor agonists are first-line therapies that improve urinary symptoms and the quality of life. For insufficient antimuscarinic response, options include dose increase, switching medications or combination therapy. However, evidence for these strategies, especially combinations with vibegron, is limited and needs further study.
The study is designed as a randomised, open-label, parallel-group, multicentre trial conducted in Japan. A total of 110 patients with OAB who met the OAB criteria and did not respond adequately to the initial 4-week antimuscarinic treatment will be randomised in a 1:1 ratio into two groups: an add-on group in which vibegron 50 mg/day is added to the current antimuscarinic drug and a switch group in which the current antimuscarinics are discontinued and replaced with vibegron 50 mg/day. The primary endpoint is the intergroup comparison of changes in daily urinary frequency between the add-on group and the switch group at 12 weeks after the initiation of protocol treatment. The primary analysis aims to confirm the non-inferiority of the switch group compared with the add-on group using a Bayesian mixed model for repeated measures. Non-inferiority will be confirmed if the posterior probability that the difference in the change in urinary frequency at 12 weeks between the two groups falls within the non-inferiority margin of one-time is 80% or greater.
The trial has been reviewed and approved by the Institute of Science Tokyo Certified Clinical Research Review Board (approval number: NR2024-001). Participants will provide informed consent to participate before taking part in the study. Results will be reported in a separate publication.
Japan Registry of Clinical Trials (jRCT) (jRCTs031240134).
膀胱过度活动症（OAB）是一种以尿急为特征的病症，常伴有尿频和夜尿症。抗毒蕈碱药物和β3受体激动剂是改善尿路症状和生活质量的一线治疗方法。对于抗毒蕈碱药物反应不足的情况，可选择增加剂量、更换药物或联合治疗。然而，这些策略的证据，尤其是与维贝格隆联合使用的证据有限，需要进一步研究。
本研究设计为在日本进行的一项随机、开放标签、平行组、多中心试验。共有110名符合OAB标准且对初始4周抗毒蕈碱治疗反应不佳的OAB患者将按1:1的比例随机分为两组：加用组，在当前抗毒蕈碱药物基础上加用维贝格隆50毫克/天；换药组，停用当前抗毒蕈碱药物，改用维贝格隆50毫克/天。主要终点是方案治疗开始后12周时加用组和换药组之间每日尿频变化的组间比较。主要分析旨在使用贝叶斯重复测量混合模型确认换药组相对于加用组的非劣效性。如果两组在12周时尿频变化差异落在单次非劣效界值范围内的后验概率为80%或更高，则确认非劣效性。
该试验已由东京科学研究所认证临床研究审查委员会审查并批准（批准号：NR2024 - 001）。参与者将在参与研究前提供知情同意。结果将在单独的出版物中报告。
日本临床试验注册中心（jRCT）（jRCTs031240134）。
