The writer is the director of mental health at the Wellcome Trust

Psychiatric medication is controversial. While most recognise that mental health problems are caused by a tangle of psychological, social and biological factors, debates about solutions are polarised between those advocating for addressing environmental factors and those more interested in medication.

This point of contention is part of the reason that, for too many years, progress in psychiatric pharmaceutical development has been at a near standstill. Drugs work by acting on a “target” — often a protein or a receptor — to produce a therapeutic effect. Innovation in drug development is usually driven by the discovery of new targets. However, the vast majority of mental health medicines prescribed today have the same targets as their pre-1960 prototypes. Most of them were discovered by serendipity; we know surprisingly little about their underlying mechanisms.