Magic Mushroom Treatment for Depression One Step Closer After Psilocybin Passes Safety Test

Scientists hope the active ingredient in magic mushrooms is a step closer to being used as a treatment for depression, after it passed a clinical safety trial.

In what was the largest controlled study of psilocybin, researchers at King's College London in the U.K. tested the drug on 89 volunteers aged around 35. They found psilocybin caused no serious problems, including to participants' cognition and emotional functions.

The team at the Institute of Psychiatry, Psychology and Neuroscience gave the participants either 10 or 25mg of psilocybin, or a placebo drug to the control group. The drugs were randomly assigned, and the subjects didn't know which they would receive. The subjects were healthy, and didn't have any past history of mental illness, including major depression, schizophrenia, psychosis or bipolar disorder, according to the researchers.

The participants received one-to-one support and supervision during the sessions, which lasted around six hours. They were allowed to go home once the "acute" effects of the drugs had worn off according to the researchers. After taking the psychedelic substance, the volunteers were encouraged to relax and engage in introspection.

As the experiment unfolded, the investigators made notes of the participants' vital signs, and checked whether they appeared to have an increased risk of suicide.

The volunteers were assessed before and after taking psilocybin, and visited a therapist to discuss their experiences.

Researchers documented 511 of what are known as adverse events, including hallucinations, changes to mood, feelings of euphoria, tiredness and shifts in how they perceived time. The vast majority of these happened on the day the volunteers took the hallucinogenic drug.

Tracy Cheung, chief communications officer of mental health care company Compass Pathways, which provided a synthetic psilocybin formulation for the study, told Newsweek the experiences "were of an expected psychedelic nature, with expected changes in perception and mood being the most frequently reported."

The team concluded psilocybin was "well-tolerated," led to no serious adverse events and caused no withdrawal symptoms in the participants.

The results were presented at the annual meeting of the American College of Neuropsychopharmacology (ACNP).

The synthetic psilocybin used in the study was provided by mental health care company Compass Pathways, which calls its formulation COMP360. The firm is currently also running a phase two randomized control trials of psilocybin for treatment-resistant depression, taking place across Europe and North America, according to its website.

Lead investigator of the safety trial Dr. James Rucker, consultant psychiatrist and senior clinical lecturer in psychopharmacology at King's College London's Institute of Psychiatry, Psychology and Neuroscience, said in a statement: "This is the largest controlled study of psilocybin to date. The results of the study are clinically reassuring and support further development of psilocybin as a treatment for patients with mental health problems that haven't improved with conventional therapy, such as treatment-resistant depression."

Dr. Ekaterina Malievskaia, co-founder of Compass Pathways, said in a statement: "This study is part of our overall clinical development program in treatment-resistant depression; we wanted to look at the safety and tolerability profile of our psilocybin, and to look at the feasibility of a model where up to six one to one sessions are held at the same time.

"We are focused on getting psilocybin therapy safely to as many patients who would benefit from it as possible," she said. "We are grateful to the many pioneering research institutions whose work over the years has helped to demonstrate the potential of psilocybin in medicine."

The research comes amid what is known as the psychedelic renaissance, as researchers around the world investigate the potential benefits of using psychedelic drugs in controlled medical settings to treat mental disorders like depression, anxiety and PTSD. The drugs under the spotlight include LSD and magic mushrooms, as well as MDMA, ayahuasca and peyote ibogaine. Scientists are also investigating the use of ketamine, which is an anesthetic rather than a hallucinogenic. Experts stress the drugs should not be used outside of clinical settings, without the supervision of a medical professional.

This article has been updated with comment from Tracy Cheung.