Proof of Concept Trial of Tanezumab for the Treatment of Symptoms Associated With Interstitial Cystitis

Abstract

In this randomized, double-blind, placebo controlled phase 2 study we investigated tanezumab, a humanized monoclonal antibody that specifically inhibits nerve growth factor as a treatment for interstitial cystitis pain. Patients with interstitial cystitis received a single intravenous dose of 200 μg/kg tanezumab or placebo. Patients recorded daily pain scores (on an 11-point numerical rating scale) 7 days before attending study visits and completed a urinary symptom diary for 3 of those days. Patients also completed the Interstitial Cystitis Symptom Index questionnaire and a global response assessment. The primary end point was change in average daily numerical rating scale pain score from baseline to week 6. Secondary end points included global response assessment, Interstitial Cystitis Symptom Index score, micturition and urgency episode frequency per 24 hours, and mean voided volume per micturition. The incidence of adverse events was also assessed. A total of 34 patients received tanezumab and 30 received placebo. At week 6 tanezumab produced a significant reduction from baseline in average daily pain score vs placebo (treatment difference [LS mean, 90% CI] was -1.4 [-2.2, -0.5]). A significantly higher proportion of patients on tanezumab responded as improved in the global response assessment and tanezumab also significantly reduced urgency episode frequency vs placebo. Tanezumab had no significant effect on Interstitial Cystitis Symptom Index score, micturition frequency or mean voided volume per micturition. The most common adverse events were headache (tanezumab 20.6%, placebo 16.7%) and paresthesia (tanezumab 17.6%, placebo 3.3%). Tanezumab has shown preliminary efficacy in the treatment of pain associated with interstitial cystitis.