INTRODUCTION: Bladder pain syndrome (BPS)/interstitial cystitis (IC) is 
associated with sensory lower urinary tract symptoms. Unfortunately, many of the 
existing oral treatments are ineffective in most patients of BPS/IC, which is 
the motivation for developing new drugs and therapeutic approaches. This review 
covers the latest drugs that have been investigated in BPS/IC patients. 
Intravesical treatments offer the opportunity to directly target the painful 
bladder with less systemic side effects.
AREAS COVERED: In this review, the authors analyze the existing literature 
supporting the treatment of BPS/IC with conventional drugs including heparin, 
hyaluronic acid, chondroitin sulfate, and dimethylsulfoxide (DMSO). Furthermore, 
investigational drugs such as tanezumab and adalimumab, capable of sequestering 
nerve growth factor (NGF), and Tumor necrosis factor-α (TNF- α) are discussed. 
Investigational treatments such as liposomes, botulinum toxin (BTX), liposomal 
BTX, PD-0299685 (a Ca(2+) channel ɑ2δ ligand), continuous intravesical 
lidocaine, and AQX-1125 (a novel SHIP1 activating compound) are also covered.
EXPERT OPINION: New investigational drugs offer promising improvements in 
clinical outcomes for BPS/IC patients; however, BPS/IC is a chronic pain 
disorder that is very vulnerable to a strong placebo effect. In addition, BPS/IC 
is a heterogeneous disorder that can be classified into several phenotypes. 
Since different phenotypes of BPS/IC respond differently to systemic and 
intravesical treatments, the authors believe that new drugs developed for BPS/IC 
are more likely to meet their predetermined clinical endpoints if the 
inclusion/exclusion criterion is tailored to specific phenotype of BPS/IC 
patients.