A note on disease burden and pharmaceutical R&D

We examine the relationship between research and development (R&D) expenditures and the expected impact of diseases in a simple theoretical framework that allows for intellectual property rights (IPR) protection to be strong or weak. In our theoretical model, an agent forms an expectation of the impact of a disease using a publicly available statistic on the (population level) disease burden, such as disability-adjusted life year. We show that a profit-maximising firm will exert relatively more R&D effort on diseases with intermediate expected impacts. We also discuss how a weak IPR regime alters the pattern of R&D investment.