Posted: Monday, June 13, 2022
Karim Chamie, MD, of the University of California, Los Angeles, and colleagues reported that intravesical N-803 plus bacillus Calmette-Guérin (BCG) may prove to be an effective therapeutic strategy for patients with BCG-unresponsive high-grade non–muscle-invasive bladder cancer. Additionally, with 2 years of follow-up, the bladder cancer–specific overall survival was 99% with intravesical N-803 plus BCG, and cystectomy was avoided in more than 90% of patients. These findings were presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 4508).
The study enrolled patients with BCG-unresponsive high-grade non–muscle-invasive bladder cancer. All patients were treated with intravesical N-803 plus BCG. The primary endpoint for cohort A (carcinoma in situ) was the incidence of complete response of carcinoma in situ at any time. The primary endpoint for cohort B (papillary) was disease-free rate at 12 months.
Of the 160 patients enrolled in the study, 83 were in cohort A and 77 were in cohort B. In the overall population, the median age was 72 years, and 81% were male. The mean number of prior transurethral resections of bladder tumor was four. The median number of prior BCG doses was 12.
Patients with carcinoma in situ had a complete response rate of 71%, with a median duration of response of 24.1 months. In patients with papillary cancer, the 12-month disease-free survival rate was 57%, the 24-month disease-free survival rate was 48%, and and 95% avoided cystectomy. The median time before cystectomy in four responders was 12.9 months compared with 7.8 months in eight nonresponders.
The most common grade 1 or 2 treatment-related adverse events were dysuria (22%), pollakiuria (19%), hematuria (18%), fatigue (16%), and urgency (12%). There were no reports of treatment-related grade 4 or 5 adverse events or immune-related adverse events.
Disclosure: For full disclosures of the study authors, visit coi.asco.org.