先前的研究顯示膀胱過動症的新藥Vibegron可有效地減少頻尿與尿急的症狀，但長期使用會不會有一樣的效果及其相關副作用是否有差異，而新藥Vibegron與anti-muscarininc的老藥tolterodine相比是否效果較好?

這篇文章一共蒐集了506位先前使用過12周vibegron或是tolterodine的病患，繼續進行雙盲的測試，研究者重新隨機分配病患使用vibegron或是tolterodine，直至52周時評估藥物的副作用及頻尿、尿急和尿失禁的次數。

最後研究顯示，一共430位病人完成試驗，在使用vibegron及tolterodine這兩組病人裡最常見的副作用為高血壓(8.8%/8.6%)、其次為泌尿道感染(6.6%/7.3%)、頭痛(5.5%/3.9%)、鼻咽喉炎(4.8%/5.2%) 及口乾(1.8%/5.2%)等。使用Vibegron平均排尿次數每天減少了2.4次，而使用tolterodine減少了2.0次，其他下泌尿道症狀像是急迫尿失禁(‒2.2 vs ‒1.7)、急尿(‒3.4 vs ‒3.2)及尿失禁次數(2.5 vs ‒1.9)，使用vibegron都比tolterodine有效。

本研究指出長期使用Vibegron是安全且有效的，目前台灣還未引進此新藥，期待未來可引進Vibegron，讓膀胱過動症的病人有更多藥物可作選擇。

Purpose: The long-term safety, tolerability and efficacy of vibegron in adults with overactive bladder were evaluated in the 40-week phase 3 EMPOWUR extension study.

Materials and methods: Patients who completed 12 weeks of once-daily vibegron 75 mg or tolterodine 4 mg extended release in EMPOWUR continued double-blind treatment; patients who completed 12 weeks of placebo were randomly assigned 1:1 to receive double-blind vibegron or tolterodine. The primary outcome was safety, measured by incidence of adverse events. Secondary outcomes included change from baseline at week 52 in average daily number of micturitions and urgency episodes (all patients), and urge and total urinary incontinence episodes (patients with overactive bladder wet) based on 7-day diary data.

Results: Of 506 patients randomized 505 received ≥1 dose of medication, and 430 (85%) completed the study. A total of 12 patients (2.4%) discontinued owing to adverse events. The most common adverse events with vibegron/tolterodine (>5% in either group) were hypertension (8.8%/8.6%), urinary tract infection (6.6%/7.3%), headache (5.5%/3.9%), nasopharyngitis (4.8%/5.2%) and dry mouth (1.8%/5.2%). Improvements in efficacy end points were maintained for patients receiving vibegron for 52 weeks; least squares mean change from baseline to week 52 in micturitions was ‒2.4 for vibegron vs ‒2.0 for tolterodine; in urge urinary incontinence episodes ‒2.2 vs ‒1.7 (p <0.05); in urgency episodes ‒3.4 vs ‒3.2; and in total incontinence episodes ‒2.5 vs ‒1.9 (p <0.05). Among patients with overactive bladder wet 61.0% receiving vibegron experienced ≥75% reduction in urge urinary incontinence episodes after 52 weeks of treatment vs 54.4% with tolterodine, while 40.8% vs 34.2% experienced a 100% reduction.

Conclusions: Vibegron demonstrated favorable long-term safety, tolerability and efficacy in patients with overactive bladder, consistent with results of the 12-week study.

Trial registration: ClinicalTrials.gov NCT03583372