GAG-therapy Efficacy Trial Solution for Bladder Pain Syndrome/ Interstitial Cystitis (GETSBI Study)

Rationale: Efficacy study (RCT) for glycosaminoglycan(GAG)-therapy for the indication bladder pain syndrome / interstitial cystitis with Hunner lesion subtype (BPS-IC H+). reason for this study is a current lack of evidence regarding its efficacy and cost-effectiveness. Main objective is to determine short and long term efficacy of GAG therapy (bladder instillations) for people with BPS-IC H+ as compared to placebo treatment on dominant symptoms such as pain and Quality of Life (QOL)