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Catechol-O-Methyltransferase (COMT) Inhibitor

Tolcapone for Decision Making

Phase < 1
Recruiting
Led By Ming Hsu, PhD
Research Sponsored by University of California, Berkeley
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Be between 18 and 65 years old
Timeline
Screening 3 weeks
Treatment Varies
Follow Up up to 4 weeks
Awards & highlights

Study Summary

This trial is investigating the relationship between social decision-making and dopamine levels in the brain, in order to better understand how this affects healthy and patient populations.

Who is the study for?
This trial is for right-handed individuals aged 18-40 with good general health and normal vision, who can consent to the study. It's not open to those on psychoactive meds, with a history of brain injury or psychiatric disorders, severe blood pressure issues, low IQ (<70), recent substance abuse (except nicotine), or major neurological conditions.Check my eligibility
What is being tested?
The study tests how dopamine affects social decision-making using Tolcapone (a medication) and fMRI scans. Participants will take Tolcapone and undergo brain imaging while performing tasks that measure their social decisions.See study design
What are the potential side effects?
Tolcapone may cause side effects like liver problems, muscle stiffness, confusion, fever; however specific side effects related to this trial are not listed but would be monitored by the research team.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~up to 4 weeks
This trial's timeline: 3 weeks for screening, Varies for treatment, and up to 4 weeks for reporting.

Treatment Details

Study Objectives

Outcome measures can provide a clearer picture of what you can expect from a treatment.
Primary outcome measures
Behavioral responses in neuroeconomic tasks
Blood oxygen level dependent (BOLD) activity

Side effects data

From 2018 Phase 4 trial • 95 Patients • NCT01041274
18%
Weight increase
10%
Tachycardia
6%
Psychiatric Hospitalization
6%
Hypertension
6%
Loss of libido
4%
Concentration impaired
4%
Appetite increase
4%
Memory impaired
4%
Rash
4%
Restlessness
4%
Amenorrhea
2%
Drooling
2%
Dizziness upon standing
2%
Apathy
2%
Sleep disturbed
2%
Anorgasmia
2%
Blurred vision
2%
Drug abuse
2%
Akathisia
2%
Appetite decrease
2%
Drug-related hospitalization
2%
Cellulitis
2%
Hot flashes
2%
Medical Hospitalization
2%
Fatigue
2%
Hiccup
2%
Hit by a motorcycle
2%
Hurt when riding a bike
2%
Mental activity decreased
2%
Muscle twitch
2%
Sleeplessness
2%
Pneumonia
2%
Nightmares
2%
Teeth grating
2%
Incarceration
2%
Sensory hallucinations
100%
80%
60%
40%
20%
0%
Study treatment Arm
Placebo
Citalopram

Trial Design

2Treatment groups
Experimental Treatment
Placebo Group
Group I: TolcaponeExperimental Treatment2 Interventions
Tolcapone is a brain penetrant catechol-O-methyltransferase (COMT) inhibitor. It will be administered in a single 200mg dosage once in randomized, double-blind, counterbalanced fashion with a placebo.
Group II: PlaceboPlacebo Group1 Intervention
Placebo will be administered in a single pill once in randomized, double-blind, counterbalanced fashion with a placebo.
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
Tolcapone 200 MG
2018
Completed Phase 3
~20

Find a Location

Who is running the clinical trial?

Lawrence Berkeley National LaboratoryUNKNOWN
1 Previous Clinical Trials
3,179 Total Patients Enrolled
University of California, BerkeleyLead Sponsor
181 Previous Clinical Trials
721,086 Total Patients Enrolled
University of California, San FranciscoOTHER
2,510 Previous Clinical Trials
15,243,637 Total Patients Enrolled

Media Library

Tolcapone (Catechol-O-Methyltransferase (COMT) Inhibitor) Clinical Trial Eligibility Overview. Trial Name: NCT04205994 — Phase < 1
Dopamine Research Study Groups: Tolcapone, Placebo
Dopamine Clinical Trial 2023: Tolcapone Highlights & Side Effects. Trial Name: NCT04205994 — Phase < 1
Tolcapone (Catechol-O-Methyltransferase (COMT) Inhibitor) 2023 Treatment Timeline for Medical Study. Trial Name: NCT04205994 — Phase < 1

Frequently Asked Questions

These questions and answers are submitted by anonymous patients, and have not been verified by our internal team.

Is it feasible for me to join this research endeavor?

"This clinical trial requires the enrollment of 70 people aged 18 to 40 who are right-handed, possess normal or corrected vision, and be in a general state of health. A written informed consent form is also mandatory for participation as determined by screening professionals such as Dr. Kayser or Dr. Jagust (or another approved medical professional)."

Answered by AI

Are there any vacancies left for potential participants of this clinical trial?

"According to information on the clinicaltrials.gov website, this trial is still in its recruitment phase which kicked off on December 1st 2019 and was most recently updated September 1st 2022."

Answered by AI

Are there any documented studies using Functional Magnetic Resonance Imaging (fMRI)?

"Currently, there are 4 active clinical trials making use of Functional Magnetic Resonance Imaging (fMRI) technology. Unfortunately, none have yet reached Phase 3 status. Berkeley is the primary location for these studies but they are also being conducted in other parts of America too."

Answered by AI

Is this experimental protocol accepting participants of advanced age?

"To be eligible for this medical trial, the potential participant's age must fall between 18 and 40 years old. Additionally, there are 6 studies catered to those younger than 18 while another 18 trials exist dedicated to elderly persons aged 65 or above."

Answered by AI

How many participants is this research project accepting in total?

"Affirmative. According to the details on clinicaltrials.gov, this research is actively recruiting patients; it was published on December 1st 2019 and last updated in September 1st 2022. The experiment requires 70 participants from a single medical centre."

Answered by AI

Who else is applying?

What state do they live in?
California
How old are they?
18 - 65
65+
What site did they apply to?
University of California, Berkeley
What portion of applicants met pre-screening criteria?
Met criteria

How responsive is this trial?

Typically responds via
Email
Recent research and studies
clinicaltrials.govStudy
Dopaminergic Mechanisms Underlying Human Social Behavior
2019. "Dopaminergic Mechanisms Underlying Human Social Behavior". ClinicalTrials.gov. https://clinicaltrials.gov/ct2/show/NCT04205994.
~13 spots leftby May 2025
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