OBJECTIVES: : In the COU-AA-301 trial, abiraterone acetate with low-dose prednisone (AA) was found to extend survival in metastatic castrate resistant prostate cancer (mCRPC) patients progressing after docetaxel chemotherapy compared to placebo with low-dose prednisone. This study aimed to evaluate AA treatment duration in routine clinical practice in mCRPC patients in four European countries. Treatment sequencing and survival data were assessed to place the treatment duration into context. Results for France and the Netherlands are reported.

METHODS: The study was designed as a retrospective chart review. Patients were identified through treating oncologists and urologists. Eligible mCRPC patients were aged ≥18 years, previously treated with docetaxel and naïve to prior AA treatment. Baseline patient characteristics were described using summary statistics. Kaplan-Meier survival analyses were performed for AA treatment duration, overall survival (OS) and time to prostate-specific antigen (PSA) progression endpoints.

RESULTS: A total of 68 physicians (France and the Netherlands) reported data on 269 mCRPC patients treated with AA. Median PSA (ng/mL) of patients from France and the Netherlands at baseline were 56.0 (interquartile range [IQR]: 28.0-120.0) and 174.5 (IQR: 69.5-371.5), respectively. The median time (months) between mCRPC diagnosis and AA initiation was 12.6 (IQR: 7.0-27.2) in France and 18.3 (IQR: 9.6-30.2) in the Netherlands. Median (months) AA treatment duration, median OS and median time to PSA progression in France was 11.3 (95% confidence interval [95%CI]: 8.3-13.7), 21.6 (95%CI: 14.5-.) and 13.8 (95%CI: 11.0-14.7), respectively. In the Netherlands, it was 4.9 (95%CI: 3.4-6.4), 11.0 (95%CI: 7.3-13.0) and 4.9 (95%CI: 3.0-7.3), respectively. CONCLUSIONS: Here we describe the real-world treatment of mCRPC patients receiving AA in the post-chemotherapy setting in two EU countries. This study suggests that initiating AA earlier in the post chemotherapy mCRPC setting may result in better health outcomes.