Scientists have been analyzing for years, and more and more seriously, the therapeutic effect of the psychedelic substancesillegal in the United States. An estimated 100 million people worldwide suffer from treatment-resistant depression. Some experts see psychedelic substances as a possible way to help them.
The New England Journal of Medicine on Wednesday published the largest clinical trial ever conducted to evaluate the effect of psilocybina psychoactive substance found naturally in hallucinogenic mushrooms.
A single 25-milligram dose reduced symptoms of depression in people in whom several conventional treatments had failed, the new study revealed.
The researchers tested a synthetic version of psilocybin developed by British start-up Compass Pathway, which also funded the trials, which have involved 233 people from 10 countries, who discontinued ongoing treatment but received psychological support.
Participants were divided into three groups, randomly receiving 1 milligram, 10 milligrams or 25 milligrams of the treatment and were never alone in the sessions, which lasted between six and eight hours in a special room.
Some described being immersed in “a dreamlike state” that could be recalled, said James Rucker, co-author of the study, at a press conference. One participant required a sedative during the session due to anxiety. But the side effects observed (headaches, nausea, anxiety) were generally mild and disappeared quickly.
Three weeks later, those receiving 25 mg showed significant improvement compared with those receiving lower doses on a baseline measure for depression. Slightly less than 30% were in remission.
“This is the strongest evidence so far and suggests that further, larger and longer randomized trials of psychedelics are warranted,” said Andrew McIntosh, a professor of psychiatry at the University of Edinburgh, who was not involved in the study
Another expert was more cautious. “We still don’t know enough about potential side effects, particularly whether some people may experience a worsening of some symptoms,” said Anthony Cleare, professor of psychopharmacology in London, who was not involved in the study.
Phase 3 trials, involving more participants, are scheduled to begin this year and end in 2025.