A study to investigate the effects of repeated low doses of psilocybin and ketamine on cognitive and emotional dysfunctions in Parkinson’s disease and to understand its mechanism of action

This therapeutic exploratory trial (n=34) aimed to investigate the effects of repeated small doses of psilocybin and ketamine on cognitive and emotional dysfunctions in Parkinson’s disease and to understand its mechanism of action.

Conducted by Maastricht University in the Netherlands, the trial assessed the impact of these substances on various parameters such as affect, well-being, attention, neuroplasticity, cognitive performance, emotion regulation, Parkinson’s disease symptoms, and immune markers.

Participants, aged 18 and above, diagnosed with Parkinson’s disease, were required to be free from conventional Parkinson medication. The trial employed a controlled design, including a placebo, and involved a crossover methodology. Key exclusion criteria included previous experience of serious side effects to psychedelic drugs, use of conventional Parkinson’s disease medication, and history of drug addiction, among others.

The primary endpoint focused on the change in negative and positive affect scores at the end of treatment compared to baseline. Secondary endpoints included changes in quality of life, emotional attention, cognitive performance, and Parkinson’s disease symptom severity. The trial, authorised by the Competent Authority and with a favourable Ethics Committee opinion, was completed after its initial estimate of three years.

Topic Neurocognitive Disorders
Compound Placebo Psilocybin Ketamine
Country Netherlands
Visit trial
Status Completed
Results Published No
Start date 10 November 2021
End date 30 December 2024
Phase Phase II
Design Blinded
Type Interventional
Generation First
Participants 34
Sex All
Age 18- 99
Therapy No

Trial Details

This trial investigated the effects of low doses of psilocybin and ketamine on cognitive and emotional functions in Parkinson's disease. It involved 34 participants, explored various outcomes including affect, well-being, and cognitive performance, and was conducted by Maastricht University in the Netherlands. The trial was authorised by the Competent Authority and had a favourable Ethics Committee opinion, completing within its estimated three-year duration.

Trial Number 2021-000041-40

Sponsors & Collaborators

Maastricht University
Maastricht University is host to the psychopharmacology department (Psychopharmacology in Maastricht) where various researchers are investigating the effects of psychedelics.

Data attribution

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