Overactive bladder (OAB) is a condition characterized by symptoms of urgency, frequency, and nocturia, often accompanied by urinary incontinence. For patients who do not respond to pharmacological therapies, botulinum toxin type A (BoNTA) has proven effective in reducing symptoms. Traditionally administered via cystoscopic injections, this approach can be invasive and uncomfortable. Electromotive drug administration (EMDA) is a novel technique that facilitates intravesical delivery of BoNTA without requiring injections, offering a potentially safer and more comfortable alternative.

We conducted a prospective pilot study involving 43 adult patients diagnosed with refractory OAB. The intervention consisted of outpatient administration of 100 U BoNTA using EMDA technology. We performed comprehensive urodynamic evaluations before treatment and monitored patients through validated questionnaires and voiding diaries over a 12-month period. Our assessment metrics included maximal bladder capacity, daily urinary frequency, urgency episodes, and mean voided volume.

The therapeutic impact of EMDA-delivered BoNTA manifested across multiple parameters. Maximal bladder capacity showed a remarkable improvement from baseline (164.4 ml) to 241.3 ml at three months post-treatment, maintaining significant enhancement at six months (227.0 ml) and showing sustained improvement at twelve months (213.0 ml). Daily urinary frequency demonstrated a similar pattern of improvement, decreasing from 8.31 episodes per day at baseline to 6.62 at three months, with sustained benefits observed at six months (6.3 episodes) and twelve months (6.8 episodes).

Urgency episodes, a particularly troublesome symptom for patients, decreased substantially from 2.52 per day to 1.56 at three months, maintaining improvement at six months (1.8) and twelve months (2.0). Mean voided volume increased from 143.97 ml at baseline to 197.6 ml at three months, with sustained improvement throughout the follow-up period (195.0 ml at six months and 192.0 ml at twelve months).

Statistical analysis revealed significant improvements in all parameters at three and six months (p < 0.05). While the twelve-month results showed some decline in therapeutic effect, they remained clinically improved compared to baseline values. Patient satisfaction was notably high, with 94.1% of participants expressing satisfaction with the procedure and 75.2% indicating willingness to undergo repeat treatment. Safety profiles were excellent, with only two patients (4.7%) experiencing mild, transient dysuria classified as Clavien-Dindo grade I complications.

According to our findings demonstrate that EMDA-assisted BoNTA administration offers a promising therapeutic alternative for refractory OAB. The sustained improvement in urodynamic parameters and symptom scores, coupled with high patient satisfaction and minimal complications, suggests this approach could bridge the gap between oral pharmacotherapy and more invasive treatment options. The gradual decline in therapeutic effect observed at twelve months aligns with the known pharmacological properties of BoNTA and suggests a potential need for treatment repetition at appropriate intervals.

This study provides compelling evidence for the efficacy and safety of EMDA-delivered BoNTA in managing refractory OAB. The combination of significant clinical improvement, high patient satisfaction, and minimal invasiveness positions this approach as an attractive therapeutic option. While our results are promising, larger randomized controlled trials are warranted to further validate these findings and establish optimal treatment protocols.

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