End-of-life treatment patterns in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC).

92 Background: mCRPC remains the lethal form of metastatic prostate cancer with limited treatment options following disease progression on traditional therapies such as androgen receptor pathway inhibitors (ARPIs) and chemotherapy. The receipt of intensive therapies during the last three months of life may not improve survival outcomes and may instead increase toxicity and negatively affect quality of life. Therefore, in this analysis we sought to understand real-world end-of-life practice patterns in pts with mCRPC. Methods: This retrospective study utilized the US-based, electronic health record-derived deidentified Flatiron Health Research Database. Inclusion criteria: pts diagnosed with mCRPC from 1/1/2013 to 4/10/2025, information of receipt of systemic therapy and recorded date of death. Pts were categorized into two groups: treatment-free, if no systemic therapy was administered during the last three months of life, or on-treatment, if systemic therapy was received within three months preceding death. Demographic and clinical variables at their last line of therapy (LOT) initiation, including age, race, region, socioeconomic status, practice type, and insurance were summarized using medians (IQR) or proportions. Comparisons were performed using Wilcoxon rank-sum or chi-squared tests. Results: Among 27,979 pts in the enhanced cohort, 14,793 had a recorded date of death, and 9,667 of these with available first-line treatment information were eligible and included in the analysis. Of these, 5,762 pts (59.6%) were classified as on-treatment, while 3,905 pts (40.4%) were treatment-free. At the time of last LOT initiation, treatment-free and on-treatment pts had similar age, race/ethnicity distribution and socioeconomic status. Significant differences in practice type and insurance were observed. In the on-treatment group, the most common end-of-life treatments were ARPIs in 43.3% (n = 2,497) of pts, followed by taxanes in 26.1% (n = 1,503). Further baseline characteristics, and treatment patterns will be presented at the meeting. Conclusions: The majority of pts with mCRPC continued to receive systemic therapy near the end of life. These findings highlight the need for further patient-centered decision-making to balance treatment benefit and quality of life in the final months of life, earlier goals of care discussion and integration of palliative care. Limitations include retrospective nature of study and possible data missingness.