*Article*

## **Comparison of the Clinical Efficacy and Adverse Events between Intravesical Injections of Platelet-Rich Plasma and Botulinum Toxin A for the Treatment of Interstitial Cystitis Refractory to Conventional Treatment**

**Jia-Fong Jhang, Wan-Ru Yu and Hann-Chorng Kuo \***

> Department of Urology, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Tzu Chi University, Hualien 970, Taiwan

**\*** Correspondence: hck@tzuchi.com.tw

**Abstract:** Background: Intravesical injection of Botulinum toxin A (BoNT-A) and platelet-rich plasma (PRP) have been reported to alleviate bladder pain and decrease nocturia in patients with refractory interstitial cystitis/bladder pain syndrome (IC/BPS). Both treatments are novel and there has no comparison between them. This study compared the therapeutic effects and adverse events between IC/BPS patients receiving PRP or BoNT-A injections. Materials and Methods: This study retrospectively analyzed female patients with IC/BPS who were refractory to conventional treatment and received BoNT-A (*n* = 26) or PRP (*n* = 30) injections within the previous two years. Patients were arbitrarily treated with four monthly injections of PRP or a single injection of 100 U of BoNT-A. All injections were followed by cystoscopic hydrodistention. The primary endpoint was the global response assessment (GRA), and secondary endpoints were changes in the O'Leary-Sant IC symptom score, visual analog score (VAS) of bladder pain, voiding diary, and uroflow measures from baseline to six months after the first injection day. Results: The baseline demographics revealed no significant difference between groups. The GRA at one, three, and six months was similar between groups. A significant improvement in IC symptom scores was noted in both groups. Although VAS was significantly improved in overall patients, no significant difference was noted between the PRP and BoNT-A groups at 6 months. Only half of the study cohort had a GRA ≥2 at six months. An increase in the post-void residual was noted one month after the BoNT-A injection, but there was no difference between groups at three and six months. More patients reported dysuria (19.2% vs. 3.3%, *p* = 0.086) and urinary tract infection (UTI, 15.4% vs. 0%, *p* = 0.041) after BoNT-A injection than after the PRP injections. The time from the first injection to receiving alternative treatment was similar between groups. Conclusion: Both intravesical PRP and BoNT-A injections have similar efficacy in IC symptom improvement. However, only half of the study cohort had a GRA of ≥2 at the six-month follow-up BoNT-A injection carries a potential risk of UTI after treatment.

**Keywords:** botox; platelet-rich plasma; interstitial cystitis; intravesical injection

**Key Contribution:** Intravesical injections of either PRP or BoNT-A are safe and effective for improving IC/BPS symptoms without significantly increasing the PVR. However, only half of patients remained effective at 6 months; repeat treatment was necessary for both groups.
