A comparative study of the diffusion of antihypertensive and antidepressant medications in Germany in Japan

Abstract

This thesis analyzes and compares the diffusion of antihypertensive and antidepressant medications in Germany and Japan during the time period of 1992 and 2003. The antihypertensive medications are classified as new, middle and old generations and the antidepressants are classified as new and old generations in this study. The demographic, economic, price, promotional, regulatory, and cultural factors that contributed to the sales level, number of compounds available in the market, and launch time of these medications are also examined using quantitative and qualitative methods at therapeutic class, generation, as well as product levels. The qualitative analysis includes discussions on the general health care systems, health care polices, and country-specific hypertension- and depression-related cultural backgrounds. Econometric tools (descriptive statistics and linear regression models) are used as means of quantitative analysis. The diffusion of different generations of medications is examined. The degree of the use of branded vs. generic medications are also compared. Finally, Chow-tests are conducted for cross-country and cross- therapeutic-class comparisons. This study finds that there are significant branded-v-generic, cross-generation, cross- class, cross-country differences in the diffusion of the selected therapeutic classes in the two countries. The factors examined contributed to the diffusion to various extents. Among which, the cultural factor played an important role in the adoption and sales of new medications of both therapeutic classes in both countries, especially the antidepressants in Japan. The promotional factors appear not to be very significant in the sales volumes, partially due to the regulatory settings of the two national-based health care systems.