What does “clinically meaningful” actually mean in psychiatry?

Compass Pathways recently reported Phase 3 results for COMP360, a synthetic psilocybin treatment for treatment-resistant depression. The company said 39% of treated patients achieved a “clinically meaningful” reduction in symptoms.

But who decides what counts as meaningful? And how should we interpret a 3–4 point difference on a scale like MADRS?

In this episode of Research Notes, I talk with Dr. Jerrold “Jerry” Rosenbaum, Stanley Cobb Professor of Psychiatry at Harvard Medical School and director of the Massachusetts General Hospital Center for the Neuroscience of Psychedelics.

Dr. Rosenbaum was not involved in the Compass study, but he has been closely watching the field and was quoted in STAT News saying the results “probably meet the bar for approval” but do not “shout out to you that this is miraculous.”

We discuss:

• What makes a treatment effect clinically meaningful in psychiatry
• How clinicians think about response, remission, and symptom scales like MADRS
• Why Compass introduced a new category of “clinically meaningful” improvement
• How restrictive trial criteria can make psychiatric studies hard to interpret
• Why average effects may hide meaningful benefit in subgroups
• Whether a 3–4 point difference on MADRS matters clinically
• Why durability, cost, and functional unblinding matter for psychedelic treatments

A key point from Dr. Rosenbaum: psychiatric trial outcomes are not just numbers on a page. They are consensus-based tools meant to approximate something much messier and more human — whether a person is suffering less, functioning better, and able to live their life again.

For more:
https://ghrbook.com/notes/clinically-meaningful.html