Efficacy of Amitriptyline for the Treatment of Painful Bladder Syndrome (PBS) in Newly Diagnosed Patients

The Interstitial Cystitis Clinical Trials Group (ICCTG) RCT1 was a pilot clinical trial using a 2x2 factorial study design with double masked drug treatment to evaluate the feasibility of oral pentosan polysulfate (PPS) and oral hydroxyzine in patients with interstitial cystitis (IC). IC is a bladder syndrome characterized as painful, debilitating and chronic, with no widely accepted effective treatment. Characteristic symptoms include pain with bladder filling, and marked urinary frequency (to relieve pain). The presentation of symptoms can be quite variable among patients, suggesting that IC is a multi-factorial syndrome with several proposed etiologies, some of which may be interrelated.
Subjects with IC were randomized over 18 months and followed for 24 weeks. The primary endpoint was a patient reported global response assessment (GRA) of overall symptoms. Secondary endpoints included symptom indexes and patient reports of urinary pain, urgency and frequency. The low global response rates for PPS and hydroxyzine suggest that neither provided benefit for the majority of patients with IC.

间质性膀胱炎临床试验组（Interstitial Cystitis Clinical Trials Group, ICCTG）开展的RCT1试验属于先导性临床试验，采用2×2析因研究设计与双盲药物治疗方案，旨在评估口服戊聚糖多硫酸盐（pentosan polysulfate, PPS）与口服羟嗪治疗间质性膀胱炎（interstitial cystitis, IC）患者的可行性。间质性膀胱炎是一种以疼痛、衰弱性、慢性为特征的膀胱综合征，目前尚无广泛认可的有效治疗手段。其典型症状包括膀胱充盈时疼痛，以及为缓解疼痛而出现的显著尿频。患者间的症状表现差异显著，提示间质性膀胱炎是一种多因素综合征，目前已提出多种致病病因假说，其中部分假说可能存在相互关联。
本研究共纳入间质性膀胱炎患者，于18个月内完成随机分组，并对受试者进行为期24周的随访。主要终点为患者报告的整体症状缓解评估（global response assessment, GRA）；次要终点包括症状指数评分，以及患者报告的尿路疼痛、尿急与尿频情况。
口服戊聚糖多硫酸盐与羟嗪的整体症状缓解率较低，提示二者均未对大多数间质性膀胱炎患者产生治疗获益。