Eroom's Law

Eroom's law is the observation that drug discovery is becoming slower and more expensive over time, despite improvements in technology (such as high throughput screening, biotechnology, combinatorial chemistry, and computational drug design), a trend first observed in the 1980s. The cost of developing a new drug roughly doubles every nine years. In order to highlight the contrast with the exponential advancements of other forms of technology (such as transistors) over time, the law was deliberately spelled as Moore's law spelled backwards.

The law is attributed to four main causes.

While some suspect a lack of "low hanging fruit" as a significant contribution to Eroom's law, this may be less important than the four main causes, as there are still many decades worth of new potential drug targets relative to the number of targets which already have been exploited, even if the industry exploits 4-5 new targets per year. There is also space to explore selectively non-selective drugs (or "dirty drugs") that interact with several molecular targets, and which may be particularly effective as central nervous system (CNS) therapeutics, even though few of them have been introduced in the last few decades.

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