Real-World Utilization of Androgen Deprivation Therapy-Intensification Among Older Canadian Men with de Novo Metastatic Prostate Cancer
Abstract Background Despite the wealth of evidence demonstrating the efficacy of treatment intensification beyond androgen deprivation therapy (ADT) among patients with de novo metastatic castration-sensitive prostate cancer (mCSPC), little is known of its real-world utilization. This study examined the real-world uptake of ADT treatment intensification among older men in a large Canadian province. Methods We performed a retrospective population-based cohort study using province-wide linked administrative data in Ontario, Canada. Patients 66 years and older with de novo mCSPC were included and their treatment with conventional ADT-based regimens, ADT plus next-generation androgen receptor-axis-targeted therapy (ARAT), and ADT plus docetaxel were identified and stratified by time. Results From 2014 to 2019, 3556 patients were identified with de novo mCSPC. Most patients (n = 2794, 78.6%) were treated with a conventional ADT regimen while 399 (11.2%) patients received ADT intensification with docetaxel and 52 (1.5%) patients received abiraterone acetate plus prednisone (AA+P). In a time-stratified analysis of ADT intensification before and after the pivotal AA+P trial (LATITUDE), AA+P uptake increased from 0.5% to 3.0% while docetaxel use dropped from 12.0% to 10.0%. The median survival of the study population was 18 months (IQR = 10–31). Conclusion The majority of patients with de novo mCSPC are treated with ADT alone in the Canadian real-world setting, despite randomized clinical trial evidence of benefit with the use of ADT-intensified regimens. As ADT treatment intensification is substantially under-used, better understanding the barriers to treatment and targeted education to address these are needed.