Psilocybin study focuses on patients with metastatic cancer

A clinical trial will explore whether psychedelic-assisted group psychotherapy can reduce the anxiety of the sobering diagnosis.

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Recruitment has begun for a small study of whether psilocybin, in the setting of group psychotherapy, can reduce anxiety related to a diagnosis of metastatic cancer. 

Psilocybin is the psychedelic compound found in some species of mushrooms. In November 2019, the U.S. Food and Drug Administration classified its assistive role in psychotherapy as a "breakthrough therapy" for depression.

“Studies have explored psilocybin’s value among people with cancer, but in a format of two therapists to one patient. Other researchers have seen impressive benefits of psilocybin in reducing anxiety and depression in a group setting.  I am asking the question of whether we could have a similar benefit for people with cancer in a group,” said Dr. Anthony Back, a UW Medicine oncologist and palliative-care specialist.

He will lead the study, which will include a maximum of 56 people and be based solely at the University of Washington School of Medicine. He expects to announce findings in about two years.

“This study is a safety and efficacy test of different group sizes with a four-person facilitation team,” Back said. “The first group will be five participants and four facilitators. If there are no adverse events, we’ll gradually increase the group to eight participants. We can change group size based on adverse events that might emerge.”

All participants will experience multiple group-therapy sessions. The first two and last two sessions will take place via online conferencing. For the third session, participants will be at a rustic site in western Washington for a three-day retreat, during which they each will receive a single capsule of psilocybin during a group session expected to last six to seven hours, Back said. No participant will receive a placebo.

Back treats patients who are facing cancer and dealing with the threat of disease progression and death.

“There are many, many people who are worried about having a difficult death, about leaving people they love, about being unable to do things that give their life meaning. And how you cope with all those worries is a huge quality-of-life issue.

“The idea of this (psilocybin) treatment is to allow people to experience a new perspective on what they're dealing with. It is the hope that we can help people come to terms so they can find a way to live in the moment, without having to pretend they aren’t ill or tell people that they're just fine when they're not, or pretend that it's not sad when it can be sad.”

Trial-based adverse events could encompass “really intense emotional moments during the psilocybin journey,” Back said. He added that experienced therapists will be ready to help participants talk through their emotions.

The Steven & Alexandra Cohen Foundation is funding the study. Filament Health is providing the botanical psilocybin drug candidate PEX010, a mushroom extract, for the trial.


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