For the first time ever, researchers are studying the home use of non-hallucinogenic/micro-dose levels of psilocybin — the active compound found in psychedelic mushrooms — to treat Generalized Anxiety Disorder (GAD).

The study, led by researchers at the Kingston Health Sciences Centre Research Institute (KHSC-RI), is the first-ever Health Canada approved Phase 2a clinical trial examining the effects of daily, at-home use of micro-dose psilocybin. The goal is to test if it can safely and effectively reduce symptoms of anxiety, without triggering the psychedelic effects typically associated with psilocybin.

“There are significant unmet needs among people living with Generalized Anxiety Disorder, and they are seeking effective, well-tolerated treatments,” says Dr. Claudio Soares, the study’s principal investigator at KHSC-RI, attending physician in KHSC’s Mental Health and Addiction program.

The trial will enroll up to 60 participants and involves a four-week treatment period followed by either an extension of the treatment (for another four-weeks) or a placebo (depending on random assignment). Participants will take the medication at home and are not aware of which group they were assigned.

“This study represents a major shift — a new way of targeting anxiety by engaging the brain in novel ways, but without the sedation or emotional numbing caused by many of the current medications used to treat anxiety,” says Dr. Soares, who is also a professor of Psychiatry at Queen’s University, and director of the Centre for Psychedelic Health and Research at Providence Care.

GAD affects roughly five per cent of Canadian adults — over 1.6 million people — and disproportionately impacts women. Despite its prevalence, current treatment options can be slow to work and come with side effects that make long-term use difficult to tolerate for some individuals.

Researchers are currently seeking adults living with GAD to join the study. To learn more or inquire about participation, contact the research team by email.

"Promising new therapies such as this need to be evaluated in trusted institutions that place patient safety, rigorous science, and ethical oversight at the centre of everything we do,” says Dr. David Pichora, President and CEO of KHSC. “By leading this study, KHSC and the KHSC-RI are ensuring that the search for innovative treatments happens in a safe, transparent, and responsible way."

The study is supported by grant from the Southeastern Ontario Academic Medical Organization (SEAMO) and funding from Diamond Therapeutics.

“Generalized Anxiety Disorder is one of the most common and disabling mental health conditions,” says Dr. Michael McDonnell, Chief Medical Officer at Diamond Therapeutics. “If successful, this trial could open the door to new, more accessible treatment options for people who urgently need them.”

Early research has shown that very low doses of psilocybin may improve motivation and attention without triggering a psychedelic response — suggesting that hallucinogenic effects may not be necessary to achieve mental health benefits from psilocybin for patients with GAD.

As one of the largest mental health research trials currently underway at KHSC, the study represents an important step in advancing evidence-based innovation in psychiatric care and speaks to the role KHSC-RI plays in driving mental health research in Canada.