Dopamine D2/D3 receptor binding in treatment-resistant, non-resistant depression, and healthy adults
Characterizing Dopamine D2 and D3 Receptor Binding in Treatment Resistant Depression
This project will use PET scans to see if dopamine D2/D3 receptor binding differs between adults with treatment-resistant depression, non-resistant major depression, and healthy volunteers.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 45 (estimated) |
| Ages | 25 Years to 55 Years |
| Sex | All |
| Sponsor | Unity Health Toronto Academic / other |
| Locations | 1 site (Toronto, Ontario) |
| Trial ID | NCT03537794 on ClinicalTrials.gov |
What this trial studies
This observational imaging project compares striatal and extrastriatal dopamine D2 and D3 receptor binding potential using PET in adults aged 25–55. Participants include medication-free patients with a current DSM-5 major depressive episode (HRSD-17 > 14) classified as treatment-resistant or non-resistant, plus healthy controls, with MRI used for anatomical reference. Non-resistant patients must have a prior history of response to antidepressant treatment to increase contrast with resistant cases. The goal is to define dopaminergic differences across groups to inform clinical characterization and future treatment development for treatment-resistant depression.
Who should consider this trial
Good fit: Adults aged 25–55 with a current DSM-5 major depressive episode confirmed by MINI and HRSD-17 >14 who are free of psychotropic medications for at least five half-lives and meet criteria for either treatment-resistant or non-resistant MDD, as well as healthy adults 25–55 able to undergo MRI, are ideal candidates.
Not a fit: People outside the 25–55 age range, those who cannot undergo MRI, who are pregnant or breastfeeding, who have medical conditions requiring immediate treatment, or who are currently taking psychotropic medications may not benefit or may be ineligible.
Why it matters
Potential benefit: If successful, the results could point to dopamine-based treatment targets and help tailor therapies for people with treatment-resistant depression.
How similar studies have performed: Prior PET and clinical research has implicated dopamine system abnormalities in depression, but comprehensive whole-brain D2/D3 PET characterization specifically targeting treatment-resistant depression is limited, making this approach relatively novel.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Key inclusion criteria for the MDD patients: * DSM-5 criteria for a Major Depressive Episode (MDE) within a MDD, confirmed through MINI diagnosis (Sheehan et al, 2015) * Age between 25 and 55 years * Hamilton Depression Rating Scale - 17 item (HRSD-17; Hamilton, 1960) \> 14 (moderate to severe symptoms) * Free of psychotropic medications for at least 5 half-lives before PET scanning * Ability to undergo MRI scanning (absence of metal, pacemakers, etc.) * For non-resistant patients: Previous history of response to an antidepressant, in order to increase signal to noise between resistant and non-resistant patients Key inclusion criteria for the Healthy Controls: * Ages between 25 and 55 years * Ability to undergo MRI scanning (absence of metal, pacemakers, etc.) Exclusion Criteria: Key exclusion criteria for the MDD patients: * Pregnancy/lactation * Medical condition requiring immediate investigation or treatment * Recent (\< 6 months)/current history of drug abuse/dependence * Lifetime history of psychosis, other Axis I comorbidities are allowable * Use of any psychotropic use within 5 half-lives before the PET scanning * For non-resistant patients: Failure of \> 2 antidepressant treatments of adequate dose and duration for current MDE. Key exclusion criteria for the Healthy Controls: * Pregnancy/lactation * Medical condition requiring immediate investigation or treatment * Lifetime history of any psychiatric disorder * Lifetime history of receiving an antidepressant
Where this trial is running
Toronto, Ontario
- Unity Health Toronto — Toronto, Ontario, Canada (Recruiting)
Study contacts
- Principal investigator: Sakina J Rizvi, PhD — Unity Health Toronto
- Study coordinator: Sakina J Rizvi, PhD
- Email: rizvis@smh.ca
- Phone: 416-864-6060
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.