The HELENA study: Hexvix-TURB vs. white-light TURB followed by intravesical adjuvant chemotherapy-a prospective randomized controlled open-label multicenter non-inferiority study.

Purpose: Photodynamic diagnosis and white-light TURB with adjuvant intravesical chemotherapy (ICT) is widely used in treatment of bladder cancer. This non-inferiority trial is designed to demonstrate non-inferiority regarding recurrence-free survival (RFS) of Hexvix TURB followed by immediate instillation compared to white-light TURB with immediate instillation followed by maintenance ICT.

Methods: Between 07/2010 and 12/2016, 129 patients with EORTC intermediate risk non-muscle invasive bladder cancer treated with TURB were included in this multicentre phase III study. Patients were randomized and received either white-light TURB with immediate ICT followed by maintenance ICT (n = 62, 20 mg Mitomycin weekly for 6 weeks as induction phase, afterwards 20 mg/month for 6 months) or Hexvix TURB with immediate ICT only (n = 67, 40 mg Mitomycin). Primary study endpoint was RFS after 12 months. Hexvix TURB was counted as non-inferior to white light alone if the upper limit of the one-sided 95% confidence interval of hazard ratio was lower than 1.676. Due to the non-inferiority design, the per-protocol population was used as the primary analysis population (n = 113) RESULTS: Median follow-up was 1.81 years. Hexvix group showed more events (recurrence or death) than white-light group (19 vs. 10) resulting in a HR of 1.29 (upper limit of one-sided 95%-CI = 2.45; p = 0.249). The ITT population yielded similar results (HR = 1.67); 3.18], p = 0.493). There was no significant difference in overall survival between both groups (p = 0.257).

Conclusion: Non-inferiority of Hexvix TURB relative to white-light TURB with maintenance Mitomycin instillation in intermediate risk urothelial carcinoma of the bladder was not proven. Hence a higher effect of maintenance ICT is to assume compared to a Hexvix-improved TURB only, confirming its important role in patient treatment.