A PET/MRI Study of Cobenfy on Dopamine Transmission in Schizophrenia (NCT07423546) | Clinical Trial Compass
Not Yet RecruitingPhase 1/2
A PET/MRI Study of Cobenfy on Dopamine Transmission in Schizophrenia
United States12 participantsStarted 2026-07-01
Plain-language summary
This is a single site clinical trial in which 12 participants with schizophrenia will be randomized to one of three doses of treatment with Cobenfy for 5 weeks. \[18F\]DOPA PET scans will be obtained before and after treatment to examine the effects of Cobenfy on dopamine transmission.
The overall objective of the current study is to measure Cobenfy's ability to engage its putative target (DA transmission/synthesis capacity in the striatum and midbrain as measured by \[18F\]DOPA Kicer (\[18F\]DOPA relative uptake rate)).
Who can participate
Age range
18 Years – 50 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Individuals aged 18 to 50, inclusive at screen
. Capable of understanding the study procedures and able to provide informed consent
. Diagnosed with schizophrenia, schizoaffective, or schizophreniform disorder
. Antipsychotic free at Visit 1 (by choice and for reasons unrelated to the study), and for at least 3 weeks (4 for aripiprazole, Cobenfy or LAIs) at the time of the baseline PET scan, inclusive of any antipsychotic-free time prior to consent
. PANSS total score \> 80 and \< 120
. Willing to use qualified methods of contraception (listed in section 5.3) for the study duration (for women of childbearing potential only)
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Cobenfy works differently from most antipsychotics — it targets muscarinic receptors rather than dopamine receptors directly — so what does this PET/MRI study's goal of measuring how Cobenfy affects dopamine transmission in my brain actually mean for understanding whether it might help my specific symptoms?
2Since this is a Phase 1/2 study and it's not yet recruiting, there's still limited safety and effectiveness data — given where I am in my treatment right now, would it make more sense to try an established medication first before considering a trial like this?
3This trial uses [18F]DOPA PET/MRI scans to measure brain activity, which involves a radioactive tracer and a lengthy imaging session — can you walk me through what that process would actually involve for me and whether there are any risks I should know about?
4Because the trial covers both schizophrenia and schizoaffective disorder, would my specific diagnosis affect how the researchers or my care team interpret the results, and does that matter for how useful the findings might be to my own treatment?
5The trial isn't recruiting yet, so if I'm interested, how long might the wait be before I could even be considered, and what should I be doing in the meantime to manage my condition while keeping this option open?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
[18F]DOPA Kicer ([18F]DOPA relative uptake rate)
Timeframe: Pre/post 5 weeks of Xanomeline and trospium chloride (KarXT)
. Stable dosing of herbal/dietary supplements for at least 6 weeks at the time of the first dose of Cobenfy and willingness to avoid products with known hepatotoxic ingredients (e.g., green tea extract, kratom, ashwagandha).
Exclusion criteria
. Diagnosis of moderate or severe substance use disorder within the previous month (from first PET scan)
. A history of poor or inadequate response to Cobenfy for any reason, hypersensitivity to Cobenfy or trospium or no justifiable reason to expect improvement on Cobenfy, or treatment with Cobenfy within 4 weeks of the first PET Scan
. EKG abnormality that is clinically significant including a QT interval \> 450 msec for men and \> 470 msec for women, as corrected by the Fridericia formula (QTcF)
. Pregnant or breast-feeding women. Women of child-bearing potential must have a negative serum β-hCG pregnancy test at Visit 1, must have been using an acceptable method of contraception (section 5.3) for 30 days before the study, and must agree to do so for the whole study and 30 days after (unless post-menopausal or surgically sterile)
. Any clinically significant or unstable medical illness, condition, or disorder that is anticipated to potentially compromise participant safety on study medication, including (but not necessarily limited to) the following: urinary retention, moderate or severe hepatic impairment, gastric retention, untreated narrow-angle glaucoma, hypernasality, resting heart rate \>100 bpm or systolic Blood Pressure \>150 mmHg, a history of orthostatic hypotension or abnormal orthostatic blood pressure (change in mean arterial pressure \[1/3 systolic + 2/3 diastolic\] of \> 20% between supine and standing blood pressures), known human immunodeficiency virus (i.e., by history), cirrhosis, biliary duct abnormalities, hepatobiliary carcinoma, symptomatic gallstone disease, active hepatic infections, history of bladder stones, recurrent urinary tract infections, or International Prostate Symptom Score \> 7 or any one item \> 2 (not including the nocturia item).
. Any material in the body that is a contraindication for MRI procedures or participated in prior nuclear medicine procedures in the past year that exceed FDA-defined limits when combined with radiation dosimetry from PET scanning in this protocol to avoid exceeding annual dosimetry limits (metal screener repeated before MRI scan during visit 2)
. Participants with suicidal ideation with intent or plan (indicated by affirmative answers to items 4 or 5 of the Suicidal Ideation section of the baseline C-SSRS) in the past 1 month or suicidal behavior in the past 3 months
. Laboratory abnormality that would compromise the well-being of the participant, including Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) value \> 2 times the upper limit of the laboratory normal reference range, elevated bilirubin (i.e., \>2 x upper limit of normal (ULN)), or serum prostate specific antigen (PSA) \>10 ng/ml (for men only).