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教育文化学部 地域文化学科 地域社会・心理実践講座 |
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Essays on competition in the pharmaceutical industry
Jiangyun Wan
2015年05月
単著
Abstract
Chapter 1: Patents and Entry Competition in the Pharmaceutical Industry: The Role of Marketing Exclusivity
Effective patent length for innovation drugs is severely curtailed because of extensive efficacy and safety tests required for FDA approval, raising concern over adequacy of incentives for new drug development. The Hatch-Waxman Act extends patent length for new drugs by five years, but also promotes generic entry by simplifying approval procedures and granting 180-day marketing exclusivity to a first generic entrant before the patent expires. In this paper we present a dynamic model to examine the effect of marketing exclusivity. We find that marketing exclusivity may be redundant and its removal may increase generic firms' profits and social welfare.
Chapter 2: Why Authorized Generics?: Theoretical and Empirical Investigations
Facing generic competition, the brand-name companies some-times launch generic versions themselves called authorized generics. This practice is puzzling. If it is cannibalization, it cannot be profitable. If it is divisionalization, it should be practiced always instead of sometimes. I explain this phenomenon in terms of switching costs in a model in which the incumbent first develops a customer base to ready itself against generic competition later. I show that only sufficiently low switching costs or large market size justifies launch of AGs. I then use prescription drug data to test those results and find support.
Chapter 3: The Merger Paradox and R&D
Oligopoly theory says that merger is unprofitable, unless a majority of firms in industry merge. Here, we introduce R&D opportunities to resolve this so-called merger paradox. We have three results. First, when there is one R&D firm, that firm can profitably merge with any number of non-R&D firms. Second, with multiple R&D firms and multiple non-R&D firms, all R&D firms can profitably merge. Third, with two R&D firms and two non-R&D firms, each R&D firms prefer to merge with a non-R&D firm. With three or more than non-R&D firms, however, the R&D firms prefer to merge with each other.
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Kaz Miyagiwa, Yunyun Wan
Japan and the World Economy ( Elsevier ) 78 2026年06月 [査読有り]
研究論文（学術雑誌） 国際共著
This paper develops a continuous-time model of a regional economy with an undocumented immigrant population, where unemployment stems from search frictions and criminal activity arises from random opportunities encountered by the unemployed. Featuring a dual wage-setting mechanism – mandated minimum wages for natives and negotiated wages for immigrants – the model shows that increasing the deportation of illegal immigrants with criminal records consistently reduces regional unemployment. However, the impact on crime is conditional: deportation reduces criminal activity if employing native labor is more profitable than employing immigrants. Similarly, while raising the minimum wage does not affect unemployment, it serves to reduce crime under the same profitability condition. Conversely, if employing immigrants is more profitable for firms, these policies may backfire, potentially leading to an increase in immigrant-driven crime.