近年, 日本では新薬開発の減少・開発期間の長期化・開発の海外シフトなど, 新薬の研究開発の「空洞化」が指摘されている。新規化合物質の合成から市場での供給に至るまでの新薬の研究開発のプロセスには, 薬事法に基づく法規制や健康保険法に基づく薬価基準が大きな影響を有する。新規化合物の発明段階に対して法や制度が影響を与えることは少ないが, 薬事法の規制が関わる治験・承認審査や健康保険制度下での薬価決定が新薬の発明に与える影響は小さくない。この論文では, 日本の法制度が新薬の研究開発にどのような影響を与えているかを国際比較し, 経済学の立場から検証する。分析の結果は, 治験・承認審査のためのインフラストラクチャーの整備, 治験の効率性の向上とインセンティブ付与に加え, ジェネリック医薬品に対する新薬の適切な相対価格が日本での新薬の研究開発を促す上での必要条件であることを示す。
Lately, it has been noted that the R&D of new drugs in Japan is "hollowing out" as the development of new drugs has decreased, development periods have increased, and development has shifted overseas, and so on. 
The process of R&D of new drugs, from the synthesis of new compounds to the final supply in the market, is immensely affected by laws and regulations based on the Pharmaceutical Affairs Law and the drug price standards based on the Pharmaceutical and Health Insurance Law. 
Although it is common for laws and institutions to affect new compounds at the invention phase, the effect of trials and approval inspections related to the regulations in the Pharmaceutical Affairs Law and drug price decisions under the health insurance system on the invention of new drugs is significant. 
This essay reviews the impact of the Japanese legal system on R&D of new drug, through an international comparison from an economic perspective. 
The results of the analysis indicate that the maintenance of an infrastructure for trials and approval inspections, thereby enhancing clinical trial efficiency and incentive granting and appropriate relative prices for generic pharmaceutical drugs are all necessary conditions for promoting R&D of new drugs in Japan.

論説