Study of real-world treatment patterns and adherence to bacillus Calmette-Guerin (BCG) in the context of guideline recommendations for patients with high-risk non-muscle invasive bladder cancer (NMIBC).

470 Background: Intravesical BCG is considered a first-line (1L) treatment for high-risk NMIBC patients. Since the presence of carcinoma in situ (CIS) in NMIBC is associated with increased disease progression rates and poor clinical outcomes, BCG is prioritized in clinical guidelines for NMIBC patients with CIS. However, BCG’s US shortage may negatively affect clinical outcomes in patients. This study evaluated the adequacy of BCG treatment patterns among NMIBC patients, including a subgroup with CIS. Methods: Adults with NMIBC treated with BCG were selected from de-identified IBM MarketScan Commercial, Medicare, and Medicaid Databases (1/1/2010-2/28/2021). Treatment patterns were assessed from the first BCG claim (triggering the start of 1L treatment) until the end of the patient’s observation. Consistent with real-world literature, adequate BCG induction was defined as ≥5 BCG claims within 70 days of the first BCG claim whereas adequate BCG induction and maintenance was defined as ≥7 BCG claims within 274 days of the first BCG claim. Proportions of patients with adequate BCG induction and maintenance were compared between CIS subgroup and overall NMIBC cohorts using chi square tests. Results: Of 5,803 NMIBC patients treated with 1L BCG, 1,182 (20.4%) had documentation of CIS. Overall and CIS cohorts had similar mean age (67 years; range 18-101 years). After 1L BCG, 56.6% and 71.8% of the overall and CIS cohorts had another treatment (P<.001; table). While 86.9% and 90.0% of the overall and CIS cohorts had adequate BCG induction (P=0.003), only 41.5% and 50.8% had adequate BCG maintenance (P<.001). More patients in the CIS versus overall cohort had a cystectomy (13.9% vs 9.7%; P<.001). Conclusions: In this study, most NMIBC patients treated with BCG received adequate induction; however, BCG maintenance was inadequate and most patients had another treatment following 1L BCG. Patients with CIS were more likely to have cystectomy after BCG, suggesting higher risk of progression in this subgroup. Results of this study further emphasize a need for additional available treatment options that are safe, efficacious, and tolerable. [Table: see text]