Treatment patterns in prostate cancer patients who received darolutamide in the ARAMIS trial in Spain: PARASEC study.

142 Background: Darolutamide, enzalutamide or apalutamide have demonstrated to prolong overall survival in patients with non-metastatic castration-resistant prostate cancer (nmCRPC). Despite their effectiveness, almost all patients progress to mCRPC. In the last few years, several new options for treatment of advanced prostate cancer have shown survival benefit. Darolutamide showed significantly prolonged metastasis-free survival compared with placebo in patients with nmCRPC in ARAMIS phase III trial. There is a lack of data about treatment patterns of patients that progress after receiving darolutamide in nmCRPC in the real-world setting in this new scenario with so many treatments available. Methods: This is a retrospective, observational, multicenter, longitudinal follow-up study to describe the treatment patterns received by the Spanish patients who received darolutamide in the ARAMIS study, according to standard clinical practice in Spain. This study involved at Urology and Oncology Departments of 18 selected hospitals. Results: Eighty-five patients were included in the study; median age was 76 years; 49 patients (58%) progressed to mCRPC and, of these, 35 (71%) received treatment for mCRPC; median number of lines post-progression was 2 (range 1-5). Abiraterone (22/35 [63%]) and docetaxel (10/35 [29%]) were the most commonly used drugs in the first line, docetaxel (12/21 [57%]) and cabacitaxel (12/21 [19%]) in the second line and cabacitaxel (4/12 [33%]) and docetaxel (3/12/21 [25%]) in the third line. Eleven patients received palliative radiotherapy (11/35 [31%]) and 7 (7/35 [20%]) osteoclast targeted therapy (5 zoledronate and 2 denosumab) after darolutamide. Conclusions: The results show that 29% of patients who progressed to mCRPC do not receive treatment after darolutamide and of those receiving treatment, 63% receive abiraterone, which appears not to be in line with current European guidelines. Only one-fifth of patients receive osteoclast targeted therapy, which is clearly insufficient. The variability in the duration of treatments and sequences suggests a lack of consensus in Spanish clinical practice. It is critical to explore more standardized strategies to maximize treatment effectiveness in these patients.