专利到期对药品价格和市场份额的影响分析

目的:系统评估国内外药品专利到期后价格及市场份额的变化,为促进我国创新药与仿制药的平衡发展提供循证参考。方法:计算机检索PubMed,Scopus,The Cochrane Library,CNKI,WanFang Data和VIP数据库,搜索与专利到期或专利过期对原研药或仿制药价格及市场份额影响有关的研究,检索时限为建库至2019年9月30日。由2名研究人员独立筛选文献和提取资料后,采取定性分析的方法评价专利到期对药品价格和市场份额的影响结果。结果:共纳入26篇文献,10篇涉及专利到期后药品价格和市场份额的变化,14篇只涉及专利到期后药品价格的变化,2篇只涉及市场份额的变化。结果显示,专利到期1~8年后,仿制药市场份额增大到56%~92%。在专利到期或首仿药上市后的第1~10年中,药品整体价格下降到专利到期前原研药价格的20%~98%,但原研药具有一定的价格刚性,价格变动幅度均在25%以内,且部分药品出现"仿制药竞争悖论"现象。结论:专利到期后药品整体价格下降,原研药表现出一定的价格刚性。仿制药市场份额随时间呈上升趋势,参与竞争的仿制药厂商数量、价格折扣、现行的仿制药政策等均对仿制药替代速度产生影响。

Analysis of the impact of patent expiry on drug price and market share

Objective:To systematically review the impact of patent expiry on drug price and market share,and provide evidence-based reference for promoting the balanced development of innovative drugs and generic drugs in China.Methods:PubMed,Scopus,the Cochrane Library,CNKI,WanFang Data and VIP databases were searched to identify studies on the impact of patent expiration on the prices and market shares of original or generic drugs from inception to September 31,2019.After relevance screening and data extraction,a standardized assessment was performed by two independent reviewers.Then,qualitative analysis was applied to evaluate the impact of patent expiration on the prices and market shares of original or generic drugs.Results:A total of 26 literatures were included,10 of which were related to changes in drug prices and market shares after the expiration of patents,14 related to changes in drug prices,and 2 related to changes in market shares.The identified studies indicated that the market shares of generic drugs ranged from 56%to 92%1~8 years after patent expiry,and drug prices decreased to 20%~98%of the brand drug price 1~10 years after patent expiry.The prices of original prices were rigid and varied within 25%,while some even increased after generic drugs’entry.Conclusion:After the expiration of patent,the overall drug prices decrease,and the original drugs show a certain price rigidity.The market share of generic drugs is increasing over time.The number of generic competitors,price discounts,and current generic drug policies could have an impact on the speed of generic substitution.