Analyzing the generic penetration trend in the Japanese dispensing market by therapeutic category

Abstract

Japanese government has started to implement several actions to promote the use of generics; however, the generic penetration rate in value advanced rather slowly from 15.4% in March 2006 to 18.7% in December 2009. Japanese pharmaceutical market has at least two unique facts which differentiate from other markets: timing of generics launch and pricing. These unique features may require a new entrant to consider the different marketing strategy. In this article, we observed that the penetration rate varies among therapeutic categories and the penetration curve for vasodilators, miscellaneous antineoplastics, and synthetic antibacterials is similar. Particularly, these categories had a launch of major original drugs within the examined period and the logistic regression for each category indicated that the reflection point of the curve was 21, 33, and 39 days after the generics launch, accordingly. As previous research suggests that the estimated sales revenue of the original drug is considered as a key determinant for generic drug penetration even in Japan. Japanese generics market will likely grow with a support of government generic promotion policy and the upcoming patent expiry of blockbusters. It is important to consider the entry strategy by therapeutic category and plan the early market penetration strategy.