Abstract Using a panel dataset of 82 drugs that lost exclusivity between 2009 and 2018, we examine three key variables: the number of generic entrants, the generic-to-brand price ratio, and generic share. We also undertake a comparative analysis of these variables using an earlier dataset of 40 drugs that lost exclusivity in 1992–1998. Our principal findings are: a marked decrease in the number of generic manufacturers per drug, higher generic concentration, and higher generic-to-brand price ratios in the more recent years. Despite higher generic-to-brand price ratios, however, the generics have garnered higher market share, reflecting their rising market power and the ongoing major structural changes in the pharmaceutical industry.

中文翻译：

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制药行业不断变化的市场动态

摘要我们使用由82种在2009年至2018年之间失去专有权的药物组成的面板数据集，研究了三个关键变量：仿制药进入者数量，仿制药与品牌价格比和仿制药份额。我们还使用1992年至1998年失去专有权的40种药物的较早数据集对这些变量进行了比较分析。我们的主要发现是：近年来，每种药物的仿制药生产商数量显着减少，更高的仿制药集中度，以及更高的仿制药与品牌价格比。尽管仿制药与品牌的价格比更高，但仿制药仍获得了更高的市场份额，这反映了它们的市场力量不断增强以及制药行业正在进行的重大结构变化。