Study Finds Synthetic Psilocybin Did Not Adversely Affect Cognitive Function

Compass Pathways’ proprietary synthetic psilocybin formulation COMP360 did not have detrimental effects on cognitive function, according to a phase-1 clinical trial presented at the American Society of Clinical Psychopharmacology annual meeting. 

“Psilocybin’s effects on cognitive function have not been widely or systematically studied,” James Rucker, MD, PhD, consultant psychiatrist and senior clinical lecturer in psychopharmacology at King’s College London’s Institute of Psychiatry, Psychology, and Neuroscience, told Healio Psychiatry. “Here, we report the short- and long-term effects of COMP360 psilocybin on tasks of cognitive function from the largest randomized controlled trial of psilocybin to date.”

Study participants were assigned to one of three groups—one in which participants received 10 milligrams of COMP360, another in which they received a 25mg dose, and a third in which participants received a placebo. All participants had a preparatory group session before dosing. Up to six participants received the medication simultaneously as well as one-on-one psychological support. 

At four separate times during the study period—during screening, at baseline, at week one, and four weeks after dosing—participants completed several validated cognitive measures from the Cambridge Neuropsychological Test Automated Battery. 

Overall, researchers found that study participants in the 10mg and 25mg COMP360 groups demonstrated better performance, on average, by day 29 compared to their baseline scores. They also found no difference among the two COMP360 groups when compared with the placebo group, by day 29. 

“Findings suggest that COMP360 psilocybin has no clinically relevant detrimental effects on cognitive functioning in health volunteers,” Rucker said. ““The results show some trends of positive effects, but these were minor and call for further exploration in clinical populations.”

COMP360 is being developed as a therapy for treatment-resistant depression based on previous studies of psilocybin in depressed patients.