Cost‐effectiveness of aprepitant in Japanese patients treated with cisplatin‐containing highly emetogenic chemotherapy

Chemotherapy‐induced nausea and vomiting (CINV) remains a major adverse event in cancer chemotherapy. Although aprepitant is effective in preventing CINV, an increment in financial burden for uniform use of aprepitant is a concern. The aim of the present study was to define the cost‐effectiveness of aprepitant from the perspective of the Japanese National Health Insurance system. Based on the results of a randomized phase II trial comparing an aprepitant‐containing regimen versus a nonaprepitant regimen in Japanese patients who received cisplatin‐containing highly emetogenic chemotherapy, a decision analytic model was developed. The incremental cost‐effectiveness ratio (ICER) was calculated both in the outpatient care setting (OCS) and in the inpatient care setting (ICS). The use of the aprepitant‐containing regimen was associated with improved quality of life compared with the nonaprepitant regimen, with an increment in quality‐adjusted life years (QALY) of 0.0016. The incremental total medical costs associated with the use of the aprepitant regimen were lower in the OCS than in the ICS, 6192 JPY (56.92 USD) and 9820 JPY (90.27 USD), respectively. The ICER was calculated as 3 906 698 JPY (35 910 USD) per QALY gained in the OCS and 6 195 781 JPY (56 952 USD) per QALY gained in the ICS. Cost‐effectiveness of the aprepitant‐containing antiemetic therapy was limited to the OCS, considering the threshold of willingness‐to‐pay commonly accepted (5 million JPY [45 960 USD] in Japan and 50 000 USD in the USA). The efficacy of aprepitant offsets the costs for revisiting clinics or rehospitalization added with rescue medications in the OCS.