NCT06455293 · Joshua Woolley, MD, PhD
Psilocybin Therapy for Depression in Parkinson's Disease
(PDP2)
What this study is about
The purpose of this study is to understand whether people with Parkinson's Disease and depression have improvement in their symptoms after psilocybin therapy.
View original scientific description
The purpose of this study is to understand whether people with Parkinson's Disease and depression have improvement in their symptoms after psilocybin therapy.
Interventions
DRUG
Psilocybin
Single dose of psilocybin ranging from low ("microdose") to high delivered orally in two separate drug administration sessions with psychological support and monitoring.
DRUG
Pimavanserin
Participants will receive either pimavanserin or placebo during their drug administration sessions.
Primary outcome measures
Evaluate the efficacy of psilocybin for improving depression in people living with Parkinson's disease
Time frame: Baseline to 30 days after first drug dose
Changes in depression as measured by the MADRS
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Age 40 to 80
- Comfortable speaking and writing in English
- Have neurologist-diagnosed idiopathic Parkinson's disease (PD), Hoehn and Yahr stages 1 to 3 during an "on" phase (time when medication/DBS for parkinsonian motor feature, including bradykinesia and rigidity is in effect)
- Currently experiencing depressive symptoms
- Able to attend all in-person visits at UCSF as well as virtual visits
- Have a primary care provider, neurologist, or psychiatrist who is actively managing or coordinating
Exclusion criteria
- Psychotic symptoms involving loss of insight
- Significant cognitive impairment
- Regular use of medications that may have problematic interactions with psilocybin
- A health condition that makes this study unsafe or unfeasible, determined by study physicians
Where
- San Francisco, California
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 2, 2026 · Source of record for eligibility and locations