OBJECTIVES : Patients with high-grade (HG) non-muscle invasive bladder cancer (NMIBC) have limited treatment options after adequate Bacillus Calmette-Guérin (BCG) therapy. Many eventually progress to muscle-invasive bladder cancer (MIBC). This study assessed the disease burden of progression among HG NMIBC patients initiating bladder preserving therapies (BPT) after adequate BCG induction.

METHODS : Using SEER-Medicare database (2008-2015), we identified patients diagnosed with HG NMIBC who received adequate BCG induction (≥5 weekly consecutive instillations). Patients who started BPT within twelve months of the last consecutive BCG instillation were selected. BPTs included BCG + interferon alpha, docetaxel, doxorubicin, epirubicin, gemcitabine, mitomycin C, nab-paclitaxel, thiotepa, valrubicin, or their combinations. Progression within three years of BPT initiation (index date) was defined as initiation of MIBC treatment, presence of metastases or death due to bladder cancer. Mortality, annualized healthcare resource utilization (HRU) and costs were compared between patients with versus without progression three years post-index (study period). Inverse probability of treatment weighting (IPTW) was used to adjust for differences in baseline characteristics between the groups.

RESULTS : Among the 860 HG NMIBC patients who initiated BPT, 233 progressed and 627 did not progress during the study period. Mean age was 77.8±7.1 years for those who progressed and 77.4±6.5 years for those who did not. The average follow-up was 24.5±10.2 and 27.8±10.2 months, respectively. Patients who progressed had significantly higher mortality during the study period than patients who did not progress (54.1% vs. 9.3%, P<0.001) and more hospitalizations, emergency room visits, and outpatient visits per year. Total annualized costs were significantly higher among patients who progressed vs. not ($59,774 vs. $25,820, P<0.001). Results were consistent using the IPTW approach.

CONCLUSIONS : The disease burden of progression among HG NMIBC patients receiving currently available BPT following adequate BCG induction is substantial, indicating urgent unmet need. Novel effective BPTs are needed in this patient population.