Interstitial cystitis/bladder pain syndrome (IC/BPS) is a disease of unknown etiology characterized by frequency nocturia and bladder pain. Although IC/BPS has been known for more than 100 years, current treatments are usually unsuccessful in achieving long-term bladder pain relief and irritable symptom improvement. Several intravesical or oral medications such as resiniferatoxin, pentosan polysulphate (PPS), amitriptyline, and cyclosporine have been tried, but the long-term therapeutic efficacy of these agents has not been proven. This study investigated the clinical efficacy of platelet-rich plasma (PRP) intravesical injection on patients with IC/BPS.

Forty patients with IC/BPS received four monthly intravesical injections of 12 mL PRP extracted from 50 mL of the patient’s whole blood. The primary end-point was the Global Response Assessment (GRA) at 3 months after the 4th PRP injection. Secondary endpoints included changes in O’Leary-Sant symptom score (OSS), visual analog scale (VAS) of pain, daily frequency, nocturia, functional bladder capacity (FBC), maximum flow rate, voided volume, post-void residual (PVR) volume from baseline to 3 months after the 4th PRP injection.

This study enrolled 40 patients (37 women and 3 men, aged 55.5±11.1 years) with cystoscopically proven IC/BPS. Patients received 4 intravesical injections of PRP every month, and were followed up at out-patient clinic at 1 month and 3 months after the last PRP injection. GRA improved after the 1st RP injection and the satisfaction persists till the primary end-point. The success rate was 45%, 57.5%, 67.6%, 72.0%, and 68.4% after the 1st, 2nd, 3rd, 4th, and 3 months after the 4th PRP injection, respectively. OSS and VAS also significantly decreased. The PVR did not change after repeated PRP injections, FBC increased and frequency and nocturia were decreased after PRP injections (Table 1). All patients were free of urinary tract infection and difficulty urinating.

The study results demonstrate that repeated intravesical injections of autologous PRP to increase bladder capacity and provide IC symptom improvement in patients with IC/BPS refractory to conventional therapy. Autologous PRP injection is safe and effective in selected patients. Although this pilot study lacked a placebo control, the improvements in IC/BPS symptoms and FBC after PRP treatment indicate the feasibility of such treatment for IC/BPS.

Repeated intravesical PRP injection is well tolerated and appears to be a safe and effective in medically refractive IC/BPS and provides significant symptom improvement.