OBJECTIVES: To compare the costs related to post-androgen deprivation (post-ADT) therapy with abiraterone acetate plus prednisone followed by post-chemotherapy enzalutamide (AA+P—Chemo—ENZ) versus the opposite treatment sequence (ENZ—Chemo—AA+P) for metastatic castration-resistant prostate cancer (mCRPC) patients with non-visceral metastases in the private health system in Peru.

METHODS: A health-state transition cost-consequence model was estimated to assess two treatment sequences: AA+P—Chemo—ENZ versus ENZ—Chemo—AA+P. Patients enter the model to receive AA+P or ENZ as post-ADT treatment. Those who discontinue treatment enter the active monitoring phase until they initiate docetaxel chemotherapy. Patients receiving chemotherapy can discontinue treatment and progress through active monitoring, post-chemotherapy ENZ or AA+P treatment, and palliative care states. Patients can transition to death from all states. The proportion of patients occupying a particular health state is assessed every month. Twenty years of time horizon was used to capture the whole life expectancy of patients. Direct costs and life-years were discounted at 5%. The payer’s perspective was used.

RESULTS: The total life time costs of the sequence AA+P—Chemo—ENZ (USD$120,687) was less costly than sequence ENZ—Chemo—AA+P (USD$131,875). It implies that USD$11,188 could be saved per patient treated (Exchange rate USD$1 = PEN$3.38). Most costs were generated during the post-ADT state (AA+P: USD$65,538; 54% of total life time costs, ENZ: USD$79,293; 60%). Costs during docetaxel chemotherapy were USD$9,508 (8%) for initial treatment AA+P and USD$10,103 (8%) for ENZ. Post-chemotherapy costs were USD$14,792 (20%) for initial treatment AA+P and USD$12,753 (10%) for ENZ.

CONCLUSIONS: The cost comparison of treatment sequences suggests that starting treatment with AA+P might result in lower total life time costs than starting treatment with ENZ, which might also yield to substantial savings per patient treated.