Impact of Novel Agents on Patient Characteristics, Treatment Patterns, and Outcomes in Patients With Metastatic Castration-resistant Prostate Cancer

Background/Aim: The therapeutic landscape for metastatic castration-resistant prostate cancer (mCRPC) has changed dramatically with the introduction of several novel agents. However, limited data are available to determine whether the introduction of novel agents affected patient characteristics, treatment patterns, and outcomes compared with the period when these agents were not available. The objective of this study was to evaluate the impact of the introduction of novel mCRPC agents on patient characteristics, treatment patterns, and outcomes. Patients and Methods: Two cohorts of Japanese patients diagnosed with mCRPC between 2009 and 2014 (Epoch 1) and 2015 and 2019 (Epoch 2) were retrospectively analyzed. Results: A total of 125 treatment-naïve mCRPC patients, consisting of 42 patients in Epoch 1 and 83 patients in Epoch 2, were evaluated. We obtained the following results: (i) a dramatic shift in the first-line treatment from docetaxel to androgen receptor axis-targeted agents (ARATs), (ii) an age range expansion for first-line treatment, and (iii) an overall survival (OS) advantage in Eopch 2 compared to Epoch 1. Multivariate analysis in the overall population showed that Epoch 2 and low prostate-specific antigen (PSA) levels at the start of first-line treatment were independent prognostic factors for OS. Conclusion: In real-world mCRPC practice, the introduction of novel agents has improved the prognosis of mCRPC while allowing more patients to receive mCRPC treatment across a broad age range. In addition, low PSA levels at the start of first-line treatment were associated with improved OS, indicating the importance of starting mCRPC treatment while PSA levels are low.