Real-world treatment patterns in metastatic castration-resistant prostate cancer progressing from metastatic hormone-sensitive prostate cancer

OBJECTIVE: To examine how changes in metastatic hormone-sensitive prostate cancer (mHSPC) management (e.g. approval of androgen receptor pathway inhibitors [ARPIs] ± docetaxel in combination with androgen deprivation therapy [ADT]) may be impacting metastatic castration-resistant prostate cancer (mCRPC) treatment patterns. METHODS: This retrospective, observational study analyzed private insurance claims data from the US Komodo Health Healthcare Map database to identify people diagnosed with mCRPC between 1 January 2020 to 31 March 2023, after progressing from mHSPC. Analyses included treatment patterns for mCRPC by line of therapy, with stratification by prior mHSPC therapy and physician specialty. RESULTS: A total of 3,151 people with mCRPC were identified. Median age was 67 years, 46% had bone-only metastases and 31% had bone + visceral metastases; 64% were treated by oncologists and 10% by urologists. Previous treatment for mHSPC included ADT only (68%), ADT + docetaxel (13%), ADT + abiraterone (8%), or ADT + non-abiraterone ARPI (11%; i.e. enzalutamide, apalutamide, or darolutamide). The most common first-line treatment for mCRPC was abiraterone in people who had received ADT alone or ADT + docetaxel for mHSPC (48% each) and chemotherapy in people who had received ADT + abiraterone or ADT + non-abiraterone ARPI for mHSPC (46% and 37%, respectively). mCRPC treatment patterns were heavily influenced by prescribing physician specialty, with oncologists more likely than urologists to prescribe abiraterone, chemotherapy or radiopharmaceuticals, and urologists more likely to prescribe non-abiraterone ARPIs. CONCLUSION: Despite changes in mHSPC management, ARPIs remain a frequent choice of first-line mCRPC therapy, with back-to-back ARPI use common. Even with the availability of other therapies beyond ARPIs, and the clinical evidence supporting use of agents beyond ARPIs, treatment with these therapies was limited.