DOI: 10.5061/dryad.q573n5tnf
title: A pilot study on the drug price revision strategy in Japan: A comparison among fiscal years 2018, 2020, and 2022

description: Objective: Japan has resumed its health technology assessment to decide
 how to reduce high-cost drug prices. While drug price rules in Japan are
 comprehensive, they do not necessarily capture differences in product
 characteristics. This study examined the drug price revision strategy in
 Japan using migraine treatment with triptans as an example. Cost data from
 fiscal years (FY) 2018, 2020, and 2022 were utilized. Methods: A
 cost-utility analysis was conducted from the perspective of healthcare
 payers, focusing on Japanese patients aged over 18 years experiencing
 migraines. The study employed a base-case model with probabilities derived
 from a network meta-analysis. Direct costs included medical and drug
 costs. Effectiveness was assessed using the European Quality of Life
 five-dimensions—3-level questionnaire. Deterministic and probabilistic
 sensitivity analyses were conducted to examine the level of uncertainty.
 Results: In FY2018, sumatriptan and eletriptan were cost-effective;
 however, the other triptans were dominated by sumatriptan. In FY2020,
 sumatriptan and eletriptan were cost-effective, and rizatriptan was
 extended-dominated; nevertheless, the other triptans were dominated by
 sumatriptan. In FY2022, naratriptan and eletriptan were cost-effective;
 however, the other triptans were dominated by naratriptan. The hierarchy
 of triptan strategies varied in each fiscal year. Conclusions: This study
 provides valuable insights into the drug price revision strategy in Japan.
 The variations could be problematic because in Japan, formulary management
 of triptans, for example, those for migraine, may face revaluation every
 other year. Discussions regarding this issue will be further explored in
 the future.
description: # A pilot study on the drug price revision strategy in Japan: A comparison
 among fiscal years 2018, 2020, and 2022 --- ### Author(s) Naoto Nakagawa,
 Phar.D., Ph.D. School of Pharmaceutical Sciences, Ohu University,
 Koriyama, Fukushima, Japan 31-1 Misumido, Tomita-machi, Koriyama,
 Fukushima 963-8611, Japan Email:
 [n-nakagawa@pha.ohu-u.ac.jp](mailto:n-nakagawa@pha.ohu-u.ac.jp) Mizuha
 Konno, BS, RPh School of Pharmaceutical Sciences, Ohu University,
 Koriyama, Fukushima, Japan 31-1 Misumido, Tomita-machi, Koriyama,
 Fukushima 963-8611, Japan Email: [715036@ohu-u.jp](mailto:715036@ohu-u.jp)
 Masami Kashiwabara, B.S., R. Ph, QOL pharmacy Email:
 [m-kashiwabara@qol-net.co.jp](mailto:m-kashiwabara@qol-net.co.jp) Shinya
 Shimoji, PhD Shimoji Neurology Clinic Email:
 [shimojishinya@icloud.com](mailto:shimojishinya@icloud.com) Jun Mochimaru,
 BS, RPh QOL pharmacy Email:
 [j-mochimaru@qol-net.co.jp](mailto:j-mochimaru@qol-net.co.jp) Tadao Inoue,
 Ph.D. Yamagata University Faculty of Medicine Email:
 [tadaino7151@gmail.com](mailto:tadaino7151@gmail.com) Leanne Lai, Ph.D.
 College of Pharmacy, Kaohsiung Medical University, Kaohsiung City, Taiwan
 Email: [LL33317@gmail.com](mailto:LL33317@gmail.com) ### **File list**
 Input data for FY2018 Input data for FY2020 Input data for FY2022 Input
 data for probabilistic sensitivity analysis for FY2018 Input data for
 probabilistic sensitivity analysis for FY2020 Input data for probabilistic
 sensitivity analysis for FY2022 ### **File descriptions** #### Details
 for: Input data for FY2018 The file is a table to analyze for input with
 TreeAge Pro.\ Format(s): .csv Dimensions: 24 rows x 5 columns Variables: *
 Name: c_XXX means cost variables (unit is 'yen'), p_XXX means
 probability variables, and u_XXX means utility variables (unit is
 'QALY'). * Description: definition of each variable. * Root
 Definition: individual variables for a base-case scenario. * Low and High
 columns: the low and the high numbers for one-way sensitivity analysis.
 #### Details for: Input data for FY2020 The file is a table to analyze for
 input with TreeAge Pro. Format(s): .csv Dimensions: 24 rows x 5 columns
 Variables: * Name: c_XXX means cost variables (unit is 'yen'),
 p_XXX means probability variables, and u_XXX means utility variables (unit
 is 'QALY'). * Description: definition of each variable. * Root
 Definition: individual variables for a base-case scenario. * Low and High
 columns: the low and the high numbers for one-way sensitivity analysis.
 #### Details for: Input data for FY2022 The file is a table to analyze for
 input with TreeAge Pro. Format(s): .csv Dimensions: 24 rows x 5 columns
 Variables: * Name: c_XXX means cost variables (unit is 'yen'),
 p_XXX means probability variables, and u_XXX means utility variables (unit
 is 'QALY'). * Description: definition of each variable. * Root
 Definition: individual variables for a base-case scenario. * Low and High
 columns: the low and the high numbers for one-way sensitivity analysis.
 #### Details for: Input data for probabilistic sensitivity analysis for
 FY2018 This file is a table to analyze to input for probabilistic
 sensitivity analysis with TreeAge Pro. Format(s): .csv Dimensions: 19 rows
 x 4 columns Variables: * Type_Distribution: data distribution. Beta shows
 that a value is from 0 to 1. * Name: d_XXX means distribution variables. *
 Param 1: alpha for beta distribution parameter * Param 2: beta for beta
 distribution parameter #### Details for: Input data for probabilistic
 sensitivity analysis for FY2020 This file is a table to analyze to input
 for probabilistic sensitivity analysis with TreeAge Pro. Format(s): .csv
 Dimensions: 19 rows x 4 columns Variables: * Type_Distribution: data
 distribution. Beta shows that a value is from 0 to 1. * Name: d_XXX means
 distribution variables. * Param 1: alpha for beta distribution parameter *
 Param 2: beta for beta distribution parameter #### Details for: Input data
 for probabilistic sensitivity analysis for FY2022 This file is a table to
 analyze to input for probabilistic sensitivity analysis with TreeAge Pro.
 Format(s): .csv Dimensions: 19 rows x 4 columns Variables: *
 Type_Distribution: data distribution. Beta shows that a value is from 0 to
 1. * Name: d_XXX means distribution variables. * Param 1: alpha for beta
 distribution parameter * Param 2: beta for beta distribution parameter ###
 Version changes August 2024: The author descriptions in the database were
 added because the author descriptions in the database and README files
 have been unified.  Feb 2024: These files have been updated because our
 previous CEA manuscript had not been accepted yet. Therefore, we have
 reanalysed in terms of different viewpoints.