Treatment Patterns and Adherence to BCG for Patients With High-Risk NMIBC

Intravesical bacillus Calmette-Guérin (BCG) is a first-line (1L) treatment for patients with high-risk non-muscle-invasive bladder cancer (NMIBC). The presence of carcinoma in situ (CIS) in NMIBC is often associated with higher rates of disease progression and poor clinical outcomes, which prioritizes BCG in clinical guidelines for patients with NMIBC. A recent study analyzed the effectiveness of treatment with BCG among patients with NMIBC, including a subgroup of patients with CIS. The results were presented at the 2023 American Society of Clinical Oncology Genitourinary Cancers Symposium.

Treatment patterns were analyzed from the first BCG claim, triggering the start of 1L treatment, until the end of patient observation. Adequate BCG induction was defined as ≥5 BCG claims within 70 days of the first claim, and adequate BCG induction and maintenance were defined as ≥7 BCG claims within 274 days of the first claim. Patients with adequate BCG induction and maintenance were compared between the overall NMIBC and CIS cohorts using chi-square tests.

Patients with NMIBC who were treated with BCG from January 1, 2010, to February 28, 2021, were chosen from the deidentified IBM MarketScan Commercial, Medicare, and Medicaid Databases. A total of 5803 patients with NMIBC who were treated with 1L BCG were selected. Of the selected patients, 1182 (20.4%) had documentation of CIS.

All patients had a similar mean age (67 years; range, 18-101 years). After 1L BCG, 56.6% and 71.8% of the overall and CIS cohorts, respectively, had another treatment (P<.001. While 86.9% of the overall cohort and 90.0% of the CIS cohort had adequate BCG induction (P=.003), only 41.5% and 50.8%, respectively, had adequate BCG maintenance (P<.001). More patients in the CIS cohort had undergone a cystectomy compared with the overall cohort (13.9% vs 9.7%; P<.001).

Most patients with NMIBC treated with BCG received adequate induction, but BCG maintenance was found to be inadequate, with most patients having to undergo another treatment following 1L BCG. Patients with CIS were more likely to have cystectomy after BCG, which suggests a higher risk of progression in that subgroup.

The study results show a need for further treatment options in addition to BCG that are both safe and tolerable.