Session: MP29: Prostate Cancer: Advanced (including Drug Therapy) II
MP29-13: Real-world Study on Darolutamide, Enzalutamide, and Apalutamide for Nonmetastatic Castration-Resistant Prostate Cancer Patients Using a Urology Network in the United States (DEAR Study)
Introduction: Second-generation androgen receptor inhibitors (ARIs) are recommended for patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) due to their ability to prolong overall survival and metastasis-free survival. Besides efficacy, drug tolerance is also important for these patients as they are often asymptomatic from their disease. However, there is limited information on real-world (RW) outcomes from the use of different ARIs. DEAR is the first study using a single data source to assess RW utilization and outcomes of darolutamide (daro), enzalutamide (enza), and apalutamide (apa) in patients with nmCRPC. Methods: This is a retrospective chart review study using electronic medical records from the Precision Point Specialty network of US urology practices. Eligible patients had nmCRPC, no prior novel hormonal therapy, and initiated first ARI treatment from August 2019 to March 2022. Patients were stratified into 3 cohorts based on the first prescribed ARI in the nmCRPC stage. This interim report describes the proportions of patients who discontinued initial ARI treatment, patients who progressed to metastatic CRPC (mCRPC), and the estimated probability of discontinuation/progression at 6, 12, 18, and 24 months using Kaplan-Meier estimates. Results: In total, 666 patients were included (daro/enza/apa, n=276/280/110). Median age (80/79/80 years), White race (68%/69%/74%), and median prostate-specific antigen doubling time (6.7/6.0/7.8 months) were similar in the daro/enza/apa cohorts at baseline. Median length of follow-up was similar (Table). Overall, fewer patients discontinued treatment in the daro cohort (27.9%) vs 37.9%/45.5% for enza/apa, and fewer patients progressed to mCRPC in the daro cohort (18.1%) compared with enza or apa (28.9%/25.5%). Generally, the estimated probability of discontinuation/progression was numerically lower for daro compared with enza or apa. Conclusions: In this interim analysis, despite similar baseline characteristics, fewer daro patients discontinued treatment or progressed to mCRPC compared with enza or apa. SOURCE OF Funding: Bayer HealthCare
