From the FDA Drug Label
Mirabegron was evaluated in three, 12-week, double-blind, randomized, placebo-controlled, parallel group, multicenter clinical trials in patients with overactive bladder with symptoms of urge urinary incontinence, urgency, and urinary frequency The co-primary efficacy endpoints in all 3 trials were (1) change from baseline to end of treatment (Week 12) in mean number of incontinence episodes per 24 hours and (2) change from baseline to end of treatment (Week 12) in mean number of micturitions per 24 hours, based on a 3-day micturition diary An important secondary endpoint was the change from baseline to end of treatment (Week 12) in mean volume voided per micturition. Results for the co-primary endpoints and mean volume voided per micturition from Studies 1,2, and 3 are shown in Table 6 Mirabegron 25 mg was effective in treating the symptoms of OAB within 8 weeks and mirabegron 50 mg was effective in treating the symptoms of OAB within 4 weeks. Efficacy of both 25 mg and 50 mg doses of mirabegron was maintained through the 12-week treatment period
Treatment Options for Urinary Urgency, Urge Incontinence, and Frequency after Midurethral Sling:
- Mirabegron (PO): Effective in treating symptoms of overactive bladder, including urge urinary incontinence, urgency, and frequency 1
- Tolterodine (PO): Also evaluated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency 2 Key Points:
- Mirabegron and tolterodine have been shown to be effective in treating symptoms of overactive bladder
- Mirabegron 25 mg and 50 mg doses were effective in treating symptoms of OAB within 8 weeks and 4 weeks, respectively
- Efficacy of both mirabegron doses was maintained through the 12-week treatment period
From the Research
Treatment for urinary urgency, urge incontinence, and frequency after a midurethral sling should prioritize conservative and pharmacological approaches, with a focus on managing overactive bladder symptoms and addressing potential urethral obstruction. The most recent and highest quality study, 3, published in 2019, provides valuable insights into the management of these symptoms. Key treatment options include:
- Behavioral modifications such as timed voiding, fluid management, pelvic floor exercises, and bladder training
- Anticholinergic medications like oxybutynin, solifenacin, tolterodine, or darifenacin
- Beta-3 adrenergic agonists like mirabegron as an alternative with fewer side effects
- Combination therapy for patients with persistent symptoms
- Physical therapy focusing on pelvic floor rehabilitation to address muscle coordination issues
- Sling revision or partial removal if urodynamic testing confirms obstruction
- Neuromodulation therapies like percutaneous tibial nerve stimulation or sacral neuromodulation for refractory cases It is essential to note that the resolution rate of urgency urinary incontinence (UUI) is significantly low in patients who had previous pelvic surgery or who preoperatively perceived UUI as a more bothersome symptom, as reported in 3. Additionally, de novo urgency and UUI can develop in a relatively small number of patients after a midurethral sling operation, highlighting the need for careful patient counseling and follow-up, as discussed in 3. The study 4 from 2016 also emphasizes the importance of managing patient expectations before sling revision, as there is a high rate of bothersome persistent and de novo urgency incontinence after sling revision. Overall, a comprehensive treatment approach, considering the patient's individual symptoms and medical history, is crucial for effectively managing urinary urgency, urge incontinence, and frequency after a midurethral sling, as supported by the findings in 5, 6, and 7.