PCN85 - Cost Effectiveness of Abiraterone Acetate Plus Prednisone in the Pre-Chemotherapy Setting Followed by Enzalutamide in the Post-Chemotherapy Setting Versus the Opposite Treatment Sequence in Metastatic Castration-Resistant Prostate Cancer Patients Under the Brazilian Private Health Care System Perspective

Abstract

ABIRATERONE ACETATE PLUS PREDNISO(LO)NE (AA+P) AND ENZALUTAMIDE (ENZ) ARE NOVEL THERAPIES targeting the androgen axis FOR THE TREATMENT OF METASTATIC CASTRATION RESISTANT PROSTATE CANCER (MCRPC)THIS STUDY MODELs THE COST-EFFECTIVENESS WITH TWO TREATMENT SEQUENCES: AA+P FOLLOWED BY DOCETAXEL (DOC) CHEMOTHERAPY AND THEN ENZ (‘AA+P-DOC-ENZ SEQUENCE’) VERSUS ENZ FOLLOWED BY DOC CHEMOTHERAPY AND THEN AA+P (‘ENZ-DOC-AA+P SEQUENCE’) IN MCRPC PATIENTS. A health economic model has been developed to estimate and compare cost consequences of these two treatment sequences in Brazil. Seven health states were considered in the model: prechemotherapy (AA+P or ENZ), active monitoring (before and after chemotherapy separately), DOC chemotherapy, post-chemotherapy (AA+P or ENZ), best supportive care, and death. Clinical data (duration of treatment, time to chemotherapy) for the model were derived from published pivotal trial results. Cost parameters were derived from available literature and cmed’s official price list. For each treatment sequence, the model estimated total costs and total costs per health state. matching adjustment of full trial population was done. discount rate considered 5%. Total costs were estimated to be R$ 262,801 for ‘AA+P-DOC-ENZ sequence’ and R$ 274,165 for ‘ENZ-DOC-AA+P sequence’ resulting in total difference of R$ 11,364. Prechemotherapy costs of AA+P and ENZ treatment were estimated to be R$ 125,560 and R$ 136,086, respectively (difference R$ 10,526). Similar costs were estimated for the two sequences, e.g., post-chemotherapy costs of AA+P and ENZ treatment were predicted to be R$ 26,309 and R$ 24,778, respectively. total life years gained for ‘AA+P-DOC-ENZ sequence’ were 3,37 against 3,28 in ‘ENZ-DOC-AA+P sequence’. total cost / life-year gained was R$ 78.058 for ‘AA+P-DOC-ENZ sequence’ and R$ 83.548 for ‘ENZ-DOC-AA+P sequence’, resulting in cost difference R$ 5.490. ‘AA+P-DOC-ENZ sequence’ was cost-saving from a Brazilian payer perspective compared with ‘ENZ – DOC-AA+ P sequence’. therefore starting treatment with AA+P may result in savings.