Overview
As targeted androgen receptor pathway inhibitors (ARPIs) are increasingly prescribed earlier in prostate cancer treatment, more patients with metastatic castration-resistant prostate cancer (mCRPC) have already been exposed to these drugs. Despite clinical concerns that tumors may develop resistance across the entire class of ARPIs, prescribing patterns of a second, different ARPI—known as an ARPI switch—remains to be fully understood in real-world care.
Using the Flatiron Health Research Database, researchers evaluated 780 patients diagnosed with mCRPC between 2023 and 2025 who had prior ARPI exposure. The study found that 31% of patients underwent an ARPI switch for their first-line mCRPC treatment, 27% received chemotherapy, and 42% received other therapies. ARPI switch patients were significantly older (64% were aged 75 or older) and were less likely to have received advanced diagnostic imaging or genetic testing compared with those receiving chemotherapy and other treatments.
Why this matters
This research reveals that ARPI switch is frequently used in routine clinical practice, particularly for older men, despite uncertainty surrounding its effectiveness. By highlighting disparities in diagnostic testing and treatment selection, these findings emphasize an unmet need for novel therapies and clearer clinical guidelines for managing advanced prostate cancer after initial treatment fails.