Estimating the Impact of Accelerated Generic Entry on Consumer Welfare and Innovation in the Pharmaceutical Industry

战后时代的医药创新为人类福利带来了巨大的收益。为了继续取得这些进展，世界各地的公共政策制定者必须在药物获取这两个相互竞争的目标和进行新药知识产权保护所产生的研发（R&amp；D）的充分激励之间取得适当的政策平衡。在美国，这种平衡主要是由哈奇-韦克斯曼法案（Hatch-Waxman Act, 1984）设定的。然而，近年来，法院裁决、随后的立法和监管变化导致了仿制药进入市场的急剧加速，减少了原品牌药发明者获得的利润。由于缺乏跨越大量药品市场的高质量数据和合理的时间间隔，过去量化这种仿制药爆炸所产生的消费者利益的努力受到阻碍，而现代离散选择模型的需求可以估计。从20世纪90年代末到21世纪初，从产品层面获取美国药品销售数据，使该项目能够量化专利保护药品的仿制药挑战激增对特定药品市场中药品购买者（短期）消费者福利的影响。初步结果表明，收益相当大，消费者的福利收益很容易超过生产者的损失。进一步的研究将对这些收益提供更精确的估计。虽然经济学家、政策制定者和公众都清楚降低药品价格的潜在好处，但同样清楚的是，从理论上讲，加速仿制药进入市场可能会抑制进行某些药物研发的动机。该项目调动的数据资源可以确认这种跨药物市场和时间的关系的存在和强度的量化。初步结果表明，总体药物开发并没有下降，但药物创新的性质和方向已经发生了重大变化，以应对日益激烈的仿制药竞争，这可能对未来药品消费者的福祉产生重大影响。该项目将提供对这些影响的更精确的测量，可能显示在产品领域，随着特定药物类别内的仿制药竞争加剧，研究工作被转移到何处。更广泛的影响：美国最近的政策变化加速了仿制药的进入，更大的仿制药竞争有助于降低美国的药品价格。本研究项目将量化仿制药竞争加剧所带来的消费者收益，同时也将衡量仿制药竞争加剧对药物开发规模、方向和性质的影响程度。由于美国制药市场已经并将继续在全球行业利润中发挥不成比例的重要作用，因此美国的政策尤其重要的是，一方面要在获得药物和另一方面为药物创新提供足够的激励之间取得适当的平衡。该项目的研究结果将为寻求最佳平衡的政策制定者提供重要指导。

Pharmaceutical innovation in the postwar era has produced enormous gains in human welfare. To continue these advances it is essential that public policymakers around the world strike the right policy balance between the competing goals of drug access and sufficient incentives to conduct research and development (R&D) created by intellectual property protection for new drugs. In the U.S., this balance is set primarily by the Hatch-Waxman Act (1984). In recent years, however, court rulings, subsequent legislation, and regulatory changes have led to a sharp acceleration in the entry of generic drugs, reducing the profits earned by the inventors of the original branded drugs. Past efforts to quantify the consumer benefits generated by this generics explosion have been hampered by the lack of high-quality data spanning a large number of pharmaceutical product markets and a reasonable interval of time over which modern discrete choice models of demand could be estimated. Access to the universe of U.S. drug sales data at the product level from the late 1990s through the late 2000s allows this project to quantify the impact of a surge in generic challenges to patent-protected pharmaceutical products on the (short-run) consumer welfare of drug purchasers in select pharmaceutical markets. Preliminary results suggest the gains are quite large with consumer welfare gains easily outweighing producer losses. Further research will provide more precise estimates of these gains.While the potential benefits of lower drug prices are clear to economists, policymakers, and the public, it is equally clear that the acceleration of generic entry could, in theory, have a depressing effect on the incentives to conduct some kinds of pharmaceutical R&D. The data resources mobilized by this project allow for the confirmation of the existence and quantification of the strength of this relationship across drug markets and time. Preliminary results suggest that overall drug development has not declined, but that the nature and direction of pharmaceutical innovation has shifted significantly in response to rising generic competition, with potentially significant consequences for the well-being of future drug consumers. This project will provide more precise measures of these effects, potentially showing where, in the product space, research effort gets diverted as generic competition within a particular drug category rises. Broader Impacts: Recent policy changes in the U.S. have accelerated generic entry, and greater generic competition has helped lower drug prices in the U.S. This research project will quantity the consumer gains generated by rising generic competition, but also measure the extent to which the rise in generic competition has influenced the scale, direction, and nature of pharmaceutical drug development. Because the U.S. pharmaceutical market has and will continue to play a disproportionately important role in global industry profits, it is especially important that U.S. policy strike the right balance between access to drugs on the one hand and sufficient incentives for drug innovation on the other. The results of this project will be an important guide to policymakers seeking the optimal balance.