OBJECTIVES:

Enzalutamide and abiraterone acetate plus prednisone (hereafter referred to as abiraterone) are approved for the treatment of metastatic castration-resistant prostate cancer (mCRPC) in Russia, both for chemotherapy-naïve and post-chemotherapy patients. Currently, abiraterone is included in the Vital and Essential Drug List (VEDL) in Russia, while enzalutamide is not. This pharmacoeconomic evaluation compared enzalutamide and abiraterone used prior to chemotherapy in patients with mCRPC from the Russian healthcare system perspective.

METHODS:

Based on PREVAIL (enzalutamide), COU-AA-302 (abiraterone), TAX327 (docetaxel) and TROPIC (cabazitaxel) data, we proposed an mCRPC Markov chain stochastic process model and calculated medical costs (medications, adverse events treatments, treatments of bone metastases, pre-medications, pain relief and oncologist visits) associated with two options considered as best practise by Russian experts: consecutive use of enzalutamide or abiraterone, followed by docetaxel and then cabazitaxel after progression on docetaxel. We used the 8-year time horizon because >97% of patients in the model die by the end of this period. Budget impact, cost-effectiveness and cost-utility analyses were conducted for enzalutamide and abiraterone. Each of them was compared with consecutive use of docetaxel and cabazitaxel without the preceding therapy with any of the studied drugs.

RESULTS:

Enzalutamide was found to be a cost-saving option compared to abiraterone. Monthly medication costs for enzalutamide were $3760 per patient, 11.7% less than for abiraterone. The 8-year discounted total medical costs for enzalutamide and abiraterone were $114,307 and $121,272 per patient, respectively, indicating that the 8-year health budget could be cut by $696,500 per 100 mCRPC patients through treatment with enzalutamide. Enzalutamide was also found to be cost-effective compared to abiraterone when both were compared against chemotherapy alone.

CONCLUSIONS:

Enzalutamide is a cost-saving and cost-effective option compared to abiraterone and should be recommended for inclusion into the VEDL in Russia.