Do newer drugs treat fewer diseases, controlling for time since launch? Evidence from France and the U.S.

Background: More recently approved drugs have significantly fewer indications than drugs approved many years ago. One possible reason for this may be that, controlling for the number of years since approval or launch, more recently approved drugs have fewer indications (e.g. at the time of launch). The role of precision and personalised medicine has increased, and the goal of precision medicine is to provide a more precise approach for the prevention, diagnosis and treatment of disease. Drugs that have fewer indications may be 'more precise' than drugs that have many indications.

Methods: We use different kinds of data from two countries - France and the U.S. - to analyze the relationship across many drugs between the number of indications of a drug, the drug's vintage - i.e. the year in which the drug was first marketed or approved - and its age - the number of years it has been marketed.

Results: All the evidence from both countries indicates that, controlling for drug age, more recently approved drugs tend to have fewer indications than drugs approved many years ago. In the U.S., a 10-year increase in vintage is associated with a 10.7% decline in the effective number of indications of all drugs, and a 19.4% decline in the effective number of indications of drugs approved after 1989. In France, the positive effect on the number of indications of the increase in drug age was more than offset by the negative effect of the increase in drug vintage.

Conclusions: More recently approved drugs are less likely to be 'general-purpose technologies' (or even multi-purpose technologies) than older drugs. The relative importance of 'precision medicine' has increased in recent decades. Drugs that have fewer indications may be 'more precise' than drugs that have many indications.