Comparing survival in trial- versus routine-care advanced urothelial cancer patients on immune checkpoint blockade.

Purpose: Although recent trials involving first-line immune checkpoint inhibitors have expanded treatment options for patients with advanced urothelial carcinoma (aUC) who are ineligible for standard cisplatin-based chemotherapy, there exists limited evidence for whether trial efficacy translates into real-world effectiveness for patients seen in routine care. This retrospective cohort study compares differences in overall survival (OS) between KEYNOTE-052 trial participants and routine-care patients receiving first-line pembrolizumab monotherapy.

Methods: A routine-care patient cohort was constructed from the Flatiron Health database using trial eligibility criteria and was weighted to balance EHR and trial patient characteristics using matching-adjusted indirect comparisons.

Results: The routine-care cohort was older, more likely to be female, and more often cisplatin-ineligible due to renal dysfunction. ECOG performance status was comparable between the cohorts. Median OS was 9 months (95% CI 7-16) in the weighted routine-care cohort and 11.3 months (9.7-13.1) in the trial cohort. No significant differences between the Kaplan-Meier OS curves were detected (p = 0.76). Survival probabilities were similar between the weighted routine-care and trial cohorts at 12-, 24-, and 36- months (0.45 vs. 0.47, 0.31 vs. 0.31, 0.26 vs. 0.23, respectively). Notably, routine care patients had modestly lower survival at 3 months compared to trial participants (0.69 vs. 0.83, respectively).

Conclusion: Our results provide reassurance that cisplatin-ineligible aUC patients receiving first-line immunotherapy in routine care experience similar benefits to those observed in trial patients.