Posted: Wednesday, March 1, 2023
Andrea Necchi, MD, of Vita-Salute San Raffaele University, IRCCS San Raffaele Hospital and Scientific Institute, Milan, and colleagues evaluated the safety and efficacy of pembrolizumab monotherapy for patients with bacillus Calmette-Guérin (BCG)-unresponsive, high-risk, non–muscle-invasive bladder cancer. Presented during the 2023 American Society of Clinical Oncology (ASCO) Genitourinary (GU) Cancers Symposium (Abstract LBA442), results of cohort B of this study revealed no new safety signals with manageable toxicity.
“Pembrolizumab showed notable antitumor activity in patients with BCG-unresponsive non-carcinoma in situ papillary high-risk non–muscle-invasive bladder cancer after about 45 months of follow-up,” concluded the study authors. “Results suggest [these patients] who declined or were ineligible to undergo radical cystectomy may also benefit from pembrolizumab monotherapy.”
The investigators focused on 132 patients with BCG-unresponsive, high-risk, non–muscle-invasive papillary bladder cancer. Participants were administered 200 mg of pembrolizumab every week for 3 weeks for up to 35 cycles. The median number of pembrolizumab cycles was 9.5, and the median patient age was 72. Nearly half of patients had stage T1 disease (43.2%), and all participants had urothelial histology; most patients were male (78.8%). The median number of prior BCG treatments was 10.
At the median follow-up of 45.5 months, the 12-month disease-free survival rate for all patients was 41.7%. The 12-month progression-free survival rate was 88.2%, and the 12-month overall survival rate was 96.2%. After stopping pembrolizumab, 23.5% of patients underwent radical cystectomy.
Most patients experienced treatment-related adverse events (73.5%), with 14.4% reporting grade 3 to 4 events. Treatment-related adverse events led to 10.6% of patients discontinuing treatment, although no deaths from these events were reported.
Disclosure: For full disclosures of the study authors, visit coi.asco.org.
2023 ASCO GU Cancers Symposium