Real-world evidence: A retrospective-cohort study of castration-resistant advanced prostate cancer (CRAPC) patients treated with abiraterone 1000 mg or 250 mg.

Abstract

e19315 Background: The efficacy of Abiraterone 250 mg with food was established ten years ago (Ryan JCO 2010). Recent publications (Szmulewitz JCO 2018) have concluded that 1000 mg on an empty stomach or 250 mg with food have similar results. This paper focuses on our experience with patients treated with either scheme at Instituto Oncológico Henry Moore (IOHM). Methods: Between July 2013 and December 2019, CRAPC patients were treated with Abiraterone 1000 mg on an empty stomach (Group A) or 250 mg with breakfast (Group B), according to the decision of the attending physician. Both groups received 5 mg of Prednisone twice a day. All cases from Group B were included and they were matched in a 1:2 ratio with Group A by two criteria: age at diagnosis and interval between diagnosis and Abiraterone. We studied: A) response rate of PSA at 12 weeks, B) time to progression, C) post-Abiraterone survival and D) overall survival. Results: We included 99 patients in the study: 66 in Group A and 33 in Group B. The table below shows population characteristics and results. Conclusions: 1) Abiraterone 1000 mg on an empty stomach or 250 mg with food both have similar outcomes. 2) In Argentina, the monthly cost of Abiraterone 1000 mg per patient is equivalent to USD 5,300. This cost can be reduced by 75% with Abiraterone 250 mg with food without losing efficacy. [Table: see text]