Parallel imports, innovations, and generics: Competition in the German market for oral anti-diabetics

在过去几十年里，德国和其他经合组织国家的药品费用增长速度远远超过通货膨胀。因此，监管机构和决策者面临的主要挑战之一是确保向老龄化人口提供创新但负担得起的药品。对于糖尿病、癫痫或阿尔茨海默病等慢性病，在西方社会越来越多地被诊断出来，分析不断变化的市场动态，充分了解现有的监管干预措施，并最终制定适当的新政策工具尤为重要。专利在医药市场中发挥着特殊的作用，因为它们赋予公司临时垄断权，激励在风险特别高的研发环境中进行投资。因此，专利市场的特点是低竞争，高价格成本利润率，这反过来又意味着增加国家卫生系统的支出。在德国，专利市场上的竞争是通过在同一治疗市场上以类似活性成分为基础的新产品（即所谓的非专利药）的进入和从其他欧洲国家平行进口原产品而引起的。政策制定者和经济学家对后一种政策的有效性进行了颇有争议的讨论，因为平行进口并没有提高该行业的生产率，而只是允许贸易商利用各国之间的价格差异，产生套利收益，这可能会降低生产商投资研发的积极性。因此，这种政策的最终福利后果尚不清楚。我们的研究建议的主要重点是在专利药品市场的平行进口的竞争影响的实证评估。该研究是基于估计的结构计量经济学模型的医药竞争和反事实模拟的替代政策方案。为此，我们使用了2000年至2010年期间上述三个治疗市场的德国和丹麦月度价格和销售额的独特数据集。我们的方法使我们能够调查具体的监管干预措施的影响-特别是平行进口的影响-以及其他相关问题，如（i）引入创新产品的影响;和（ii）非专利产品进入市场的影响。

Pharmaceutical expenses have grown at a pace well exceeding inflation in Germany as well as other OECD countries over the last few decades. Thus, one of the major challenges for regulators and policymakers is to ensure the provision of innovative, yet affordable, pharmaceutical products to an ageing population. In the case of chronic diseases such as diabetes, epilepsy or Alzheimer`s disease, which are becoming increasingly diagnosed in western societies, it is especially important to analyze the continuously changing market dynamics, well understand the existing regulatory interventions and, ultimately, develop appropriate new policy instruments. Patents play a peculiar role in pharmaceutical markets since they grant firms temporary monopolies that incentivize investments in a particularly risky research & development (R&D) environment. Hence, on-patent markets are characterized by low competition with high price-cost margins that, in turn, imply increasing expenditures for the Statutory Health System. In Germany, competition in on-patent markets is introduced through the entry of new products based on similar active ingredients in the same therapeutic market (i.e. the so called generics) and the parallel imports of the original products from other European countries. The effectiveness of this latter policy is quite controversially discussed among policymakers and economists since parallel imports do not increase the industry`s productivity but simply allow traders to exploit price differentials across countries and generate arbitrage gains that might reduce producers' incentives to invest in R&D. Therefore, the ultimate welfare consequences of such a policy are not clear.The primary focus of our research proposal is the empirical evaluation of the competitive impact of parallel imports in on-patent drug markets. The study is based on the estimation of structural econometric models of pharmaceutical competition and the counterfactual simulation of alternative policy scenarios. To this end, we utilize a unique dataset of German and Danish monthly prices and sales in the three therapeutic markets mentioned above for the 2000 to 2010 period. Our approach allows us to investigate the impact of specific regulatory interventions -especially the effect of parallel imports- as well as other related issues such as (i) the effect of the introduction of innovative products; and (ii) the impact of market entry of generic products.