Dopamine D3 Receptor Occupancy in Bipolar Depression

Dopamine D3 Receptor Occupancy in Bipolar Depression by Cariprazine (Vraylar): Evaluating Its Antidepressant Benefit

Bipolar disorder is a common condition that can cause significant disability and risk for suicide. Second generation antipsychotic medications can be used to treat depression in bipolar disorder, yet we do not know how they work. Here, we will use a recently approved medication, cariprazine (Vraylar), to treat participants with bipolar depression. They will have brain imaging with PET scans before and during treatment to understand how the medication may be working. Particularly, we will look at the role of the D3 dopamine receptor.

Study Overview

• Status: Withdrawn
• Conditions: Bipolar Depression
• Intervention / Treatment: Drug: Cariprazine

Detailed Description

Bipolar disorder is a common and disabling condition with a high rate of suicide. The depressed phase of the disorder accounts for most of the morbidity and mortality. Only four medications are FDA approved to treat bipolar depression. They all include a second generation antipsychotic (SGA), yet the antidepressant mechanism of SGA's is unknown. Not all bipolar patients respond to these treatments, and they can have problematic side effects. There is therefore a great need to understand these medications' antidepressant mechanism of action in order to design more effective treatment options.

This will be an exploratory occupancy study with cariprazine (Vraylar) in unmedicated participants with bipolar depression (n=8). Participants will have [11C]-(+)-PHNO scans before treatment starts, after three weeks of cariprazine, and after six weeks. Participants will be randomized to two dose groups, 1.5 mg daily (n=4) and 3 mg daily (n=4). These are typical doses of the medication for bipolar depression. Serum levels of cariprazine will be measured at each PET scan.

• Study Type: Interventional
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • New York
    • New York, New York, United States, 10032
      • Columbia University Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Capacity to provide consent, and informed consent provided
2. Diagnosis of bipolar I disorder and currently meet criteria for DSM5 major depressive episode
3. Depression at enrollment of sufficient severity to score at least 16 on the first 17 items of the Hamilton Depression Rating Scale when including the atypical depression items addendum
4. Age 18-60 years old
5. Patients who are on antidepressant (SSRI, SNRI or bupropion) or antipsychotic medications at presentation will be included if they have failed that regimen, as defined as not achieving at least partial remission after an adequate dose of medications for at least four weeks. Fluoxetine will not be allowed due to its long half-life. Patients will be able to continue to take other mood stabilizer medications (lamotrigine, lithium, valproate, carbamazepine or oxcarbazepine) if they had not made changes to the dose of those medications within eight weeks of signing consent. Benzodiazepines and hypnotics are allowed throughout the study. If taking stimulant medications, they must be willing not to take these during the study.
6. Females of child-bearing potential must be willing to use an acceptable method of birth control throughout the study; abstinence if it does not require changes to usual behavior, birth control pill, male condom, IUD, dep- provera, norplant, male sterilization or female sterilization are acceptable.
7. Participant is likely to tolerate medication washout if indicated

Exclusion Criteria:

1. Diagnosis of any other major psychiatric disorders such as schizoaffective disorder, current psychotic depression. Any recent drug or alcohol use disorder; within 3 months before the study unless mild. Participant meets DSM5 criteria for manic episode at the time of screening, or has YMRS > 12.
2. Previous failed trial of cariprazine, defined by at least six weeks of treatment at the dose of 1.5 mg per day or more. Experienced intolerable side effects of cariprazine in the past. Taking any medications that are either contraindicated or that have clinically significant drug-drug interactions (such as strong CYP3A4 inducers) with cariprazine, unless there is a plan to stop these as part of the washout.
3. History of clinical deterioration when any of the medications that the participant is taking at presentation have been discontinued in the past if they will be discontinued as part of the washout.
4. First-degree family history of schizophrenia if the participant is less than 33 years old.
5. Significant active physical illness, including blood dyscrasias, lymphomas, hypersplenism, endocrinopathies, renal failure, chronic obstructive lung disease, autonomic neuropathies, peripheral vascular disease, neuromuscular disorder or tardive dyskinesia. Any medical diagnoses that would be a contraindication to cariprazine treatment, including any movement disorders. Any history of a seizure disorder.
6. Actively suicidal, as defined by expressive ideation with a plan and intent for suicide, or developing suicidal ideation that requires immediate medical or treatment intervention.
7. Active lactation
8. Electroconvulsive therapy within the past 6 months
9. Participants who endorse a history of prior head trauma and score 1.5 standard deviations below the mean of Trailmaking A & B test
10. Metal implants, cardiac pacemaker, metal prostheses, metal orthodontic appliances or shrapnel in the body unless there is confirmation that the substance is MRI compatible

11. Current, past or anticipated exposure to radiation, including:

    A. Having been badged for radiation exposure in the workplace B. Participation in nuclear medicine protocols in the past year. However, participants will be eligible if the injected dose and dosimetry of the radiotracer used are known and the cumulative annual exposure of the previous study and this study is lower than the annual limit for research participants defined by FDA (21 CFR 361.1)

12. History of claustrophobia that would prevent participation in imaging scans.
13. Inadequate understanding of English
14. Weight >350 lbs or inability to fit into the MRI scanner

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cariprazine 1.5 mg; Participants will receive 1.5 mg daily of cariprazine (Vraylar) for six weeks	Drug: Cariprazine; Participants will receive 6 weeks of cariprazine treatment; Other Names: Vraylar
Experimental: Cariprazine 3 mg; Participants will receive 3 mg daily of cariprazine (Vraylar) for six weeks	Drug: Cariprazine; Participants will receive 6 weeks of cariprazine treatment; Other Names: Vraylar

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
MADRS	Montgomery Asberg Depression Rating Scale; Minimum value 0, Maximum 60; higher values indicate greater depression severity	6 weeks

Collaborators and Investigators

• Sponsor: New York State Psychiatric Institute
• Investigators: Principal Investigator: Martin Lan, MD, Columbia University

Study record dates

Study Major Dates

• Study Start (Estimated): January 6, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): May 1, 2027

Study Registration Dates

• First Submitted: September 22, 2021
• First Submitted That Met QC Criteria: September 22, 2021
• First Posted (Actual): September 29, 2021

Study Record Updates

• Last Update Posted (Actual): April 14, 2026
• Last Update Submitted That Met QC Criteria: April 9, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Bipolar and Related Disorders; Mental Disorders; Mood Disorders; Bipolar Disorder; Physiological Effects of Drugs; Central Nervous System Depressants; Tranquilizing Agents; Psychotropic Drugs; Antipsychotic Agents; cariprazine
• Other Study ID Numbers: 8079

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No