Abstract
INTRODUCTION: Drug expenditure has increased over the past years in the USA and Europe, mainly driven by originator drugs. Generic drugs have a substantial cost-saving potential. We analysed the number of generic competitors entering the market over time, distribution of market share between originator drugs and their generic competitors and association between the number of generic competitors and price changes of originator and generic drugs in the USA, Germany and Switzerland. METHODS: In this longitudinal observational study, we included all originator drugs and their corresponding generic competitors with market entry between 2007 and 2023 in the USA, Germany and Switzerland from the IQVIA database. We extracted quarterly price and sales volume data for the same study period from the IQVIA database. Descriptive statistics and regression analyses were conducted to answer the research questions. RESULTS: 530 active substances in the USA, 406 in Germany and 108 in Switzerland were included. 3 years after competition start, an average of four generic competitors entered the market in the USA, 7.6 in Germany and 3.3 in Switzerland. An increase in the number of generic competitors was associated with an increase in average generic market share. On average, the generic market share reached 90% after the entry of five generic drugs in the USA and nine in Germany, and was not reached in Switzerland. An association between the number of competitors and relative price decrease of generic drugs was observed in all three countries. This association was also observed for originator drugs in Switzerland and Germany, but not in the USA. CONCLUSIONS: The findings indicate that policies targeting market entry and prices of generic drugs would be helpful in all three countries. More research is needed to assess the impact of previous and future policies.