A systematic review and meta-analysis on the efficacy of intravesical therapy for bladder pain syndrome/interstitial cystitis

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a chronic disease characterised by persistent irritating micturition symptoms and pain. The objective was to compare the clinical efficacy of currently available products for intravesical therapy of BPS/IC and to assess their pharmacoeconomic impact. A Pubmed/Medline database search was performed for articles on intravesical therapy for BPS/IC. A total of 345 publications were identified, from which 326 were excluded. Statistical evaluation was performed with effect size (ES) assessment of symptom reduction and response rates. The final set of 19 articles on intravesical BPS/IC therapy included 5 prospective controlled trials (CTs), the remaining were classified as uncontrolled clinical studies. The total number of patients included was 801, 228 of whom had been evaluated in a CT. For CTs, the largest ES for symptom reduction as well as response rate was observed for high molecular weight hyaluronic acid (HMW-HA), with similar findings in two uncontrolled studies with HMW-HA. The number needed to treat to achieve a response to intravesical therapy was 2.67 for intravesical pentosan polysulphate and 1.31 for HMW-HA which were superior to all other instillates. HMW-HA was significantly superior in cost effectiveness and cost efficacy to all other instillation regimes. The present meta-analysis combined medical and pharmacoeconomic aspects and demonstrated an advantage of HMW-HA over other instillation agents; however, direct comparisons between the different products have not been performed to date in properly designed controlled studies.