Background: Treatment (tx) guidelines for pts with la/mUC in England have evolved over the last decade following the approval of successive immune checkpoint inhibitors (ICIs). However, the impact of this evolution on routine clinical practice (RCP) remains unclear. We aimed to describe shifts in tx patterns and associated clinical outcomes in RCP in England. Methods: This retrospective cohort study included pts aged ≥18 years, with primary stage III/IV UC diagnosis (dx) between Jan 1, 2013 and Dec 31, 2020, in the National Cancer Registration Dataset with follow-up to May 31, 2022. Pts’ dx were stratified at Dec 31, 2017, to split the cohort into pre- and post-ICI eras. Lines of systemic therapy were derived via an algorithm using data from the Systemic Anti-Cancer Therapy dataset. Summary statistics and overall survival (OS) were calculated and compared using χ² and log-rank tests, respectively. The Kaplan-Meier method was used to estimate median OS from dx and from systemic tx initiation. Results: In the pre- and post-ICI groups, the majority of pts were male (65.7% and 65.5%) and mean modified Charlson-Deyo Comorbidity Index was 3.4 and 3.5, respectively. Mean age was 73.2 years in both groups, while a higher percentage of pts in pre-ICI era had stage IV disease at dx (68.3% and 50.0%; p<0.001). The rate of first line (1L) tx increased from 30.4% to 35.3% (p<0.001) and second line (2L) from 31.2% to 37.3% (p<0.001). The proportion of pts who received ICI in any line increased from 13.7% to 31.6% (p<0.001). Median OS from 1L tx improved from 13.8 to 15.5 mo. Conclusions: While pt demographics did not change considerably between the two groups, 1L and 2L tx rates moderately increased over time, although remained below 40%. In both groups, >85% of treated pts received 1L platinum chemotherapy, consistent with guidelines. In the post-ICI era, approximately one-third of treated pts received ICI therapy in any line. Improved OS from 1L tx could be partially attributable to the increased availability and uptake of ICIs.

*Only calculated for treated pts.