Pentosan polysulfate sodium for treatment of interstitial cystitis/bladder pain syndrome: insights from a randomized, double-blind, placebo controlled study

Nickel JC, Herschorn S, Whitmore KE, Forrest JB, Hu P, Friedman AJ, Baseman AS · The Journal of Urology

The largest and most modern placebo-controlled trial of PPS in its licensed indication found no treatment effect: 40.7% of placebo patients met the responder definition versus 39.8% on 100 mg daily and 42.6% on the labelled 300 mg daily dose. An interim analysis six years in, at 54% of the 645-patient target, ended the trial early. Tolerability matched placebo.

Population

368 adults with interstitial cystitis/bladder pain syndrome, US and Canadian multicentre, 24 weeks

Intervention

Oral PPS 100 mg once daily or 100 mg three times daily

Comparator

Matching placebo

Limitations

Manufacturer-run (Janssen) and stopped early for futility, so the final sample is smaller than planned; entry did not require cystoscopy, so the population is broader than the 1990s registration trials — which is either the reason for the null or the reason it generalizes, and the paper cannot settle which.