for cabazitaxel and four for mitoxantrone. The most frequent clinically significant grade 3/4 adverse events were neutropenia (cabazitaxel (82%) vs. mitoxantrone (58%)). The marginal efficacy of cabazitaxel vs. mitoxantrone is 2.4 months for OS and 1.4 months for PFS. Considering OS as efficacy parameter, the incremental costefficacy ratio (ICER) calculated for the two treatments is €147.389. When PFS is considered, the ICER calculated is €248.871. Conclusions Based on this analysis, the ICERs calculated for cabazitaxel are too high for it to be considered a cost-effective option in the treatment of mHRPC, when compared with mitoxantrone, in patients previously treated with a docetaxel-containing regimen. No conflict of interest.