Real-World Clinical Outcomes and Treatment Patterns Among Black and Non-Black Patients With Prostate Cancer Initiated on Apalutamide in a Urology Setting
Journal of Health Economics and Outcomes Research, 2024
Background
The use of androgen receptor signaling inhibitors, including apalutamide, in combination with androgen deprivation therapy is recommended for the treatment of metastatic castration-sensitive prostate cancer (mCSPC) and non-metastatic castration-resistant prostate cancer (nmCRPC).
Objective
To describe real-world treatment patterns and clinical outcomes among patients with mCSPC or nmCRPC who initiated apalutamide in the United States.
Methods
A retrospective cohort study of patients with mCSPC or nmCRPC who initiated apalutamide was conducted using electronic medical record data from US community-based urology practices (Feb. 1, 2017-April 1, 2022). Persistence with apalutamide was reported at 6-, 12-, and 18-months post treatment initiation. Clinical outcomes described up to 24 months after apalutamide initiation using Kaplan-Meier analyses included progression to castration resistance, castration resistance-free survival (CRFS), and metastasis-free survival (MFS). Outcomes were reported separately based on mCSPC or nmCRPC status and race (ie, Black or non-Black).
Results
This study included 589 patients with mCSPC (mean age, 75.9 years) and 406 patients with nmCRPC (mean age, 78.8 years). Using a treatment gap of >90 days, persistence with apalutamide at 12 months remained high for both the mCSPC (94.9%) and nmCRPC (92.7%) cohorts, and results were descriptively similar among Black and non-Black patients, and when a treatment gap of >60 days was considered. In patients with mCSPC, overall progression to castration resistance rates at 12 and 24 months were 20.9% and 33.5%, and overall CRFS rates were 76.2% and 62.0%, respectively. In patients with nmCRPC, overall MFS rates at 12 and 24 months were 89.7% and 75.4%, respectively. Rates of these clinical outcomes were descriptively similar between Black and non-Black patients.
Discussion
While clinical trials have demonstrated the efficacy and safety of apalutamide, there is limited real-world data describing treatment persistence and clinical outcomes among patients with mCSPC and nmCRPC who initiated apalutamide.
Conclusions
In this real-world study of patients with mCSPC or nmCRPC initiated on apalutamide, treatment persistence was high and apalutamide demonstrated robust real-world effectiveness with respect to progression to castration resistance, CRFS, and MFS, overall and among Black and non-Black patients.
Authors
Lowentritt BH, Rossi C, Muser E, Kinkead F, Moore B, Lefebvre P, Pilon D, Du S