This study aims to understand the brain changes linked to depression in people with Parkinson's disease (PD). Researchers will use a special imaging substance called 11C-UCB-J (a radiotracer for imaging) to compare brain activity in four groups: people with PD and depression, people with PD without depression, people with depression but no PD, and healthy individuals. The study is looking for participants aged 40-80. A small group of participants can also choose to receive a single dose of ketamine hydrochloride (a drug) to see if it affects these brain mechanisms and helps with depression. The main goal is to see if the Montgomery-Åsberg Depression Rating Scale (MADRS) scores improve, which would indicate a positive antidepressant response.

Study design

This is an interventional study comparing four groups of participants, with a planned enrollment of 120 people. There is also an optional subset of participants who will receive ketamine.

What's involved

You would have one screening visit and one additional visit for PET and MRI scans, totaling about 7 hours. If you opt into the ketamine arm, you would have one additional visit for a single dose of ketamine and another set of PET and MRI scans.

Compensation

Not stated in the trial record.

Follow-up

The primary endpoint, the Montgomery-Åsberg Depression Rating Scale (MADRS), is measured at one day.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.