What side effects are associated with this type of intervention?

Common treatments that modulate dopamine levels, such as levodopa, dopamine agonists, and MAO B inhibitors, can have several side effects. Levodopa may cause nausea, orthostatic hypotension, confusion, and hallucinations. Dopamine agonists can lead to side effects like nausea, dizziness, somnolence, and impulse control disorders. MAO B inhibitors are generally well-tolerated but can cause mild side effects such as headache, insomnia, and gastrointestinal discomfort. These side effects are important considerations when using dopaminergic therapies to influence cognitive mechanisms in social decision-making.

What prior FDA approvals exist?

Several FDA-approved drugs modulate dopamine levels and are used in treatments for cognitive and social decision-making mechanisms. Levodopa, often combined with carbidopa, is a primary treatment for Parkinson's disease, enhancing dopamine levels to improve motor and cognitive functions. Dopamine agonists like pramipexole and ropinirole are also approved for Parkinson's disease, mimicking dopamine's effects in the brain. Additionally, solriamfetol, a selective dopamine and norepinephrine reuptake inhibitor, is approved for treating sleepiness in narcolepsy, indirectly influencing cognitive functions. These drugs highlight the therapeutic potential of dopamine modulation in various neurological and cognitive disorders.

What other types of research exist?

Promising novel alternatives to dopamine modulators for patients in 2024 include: 1) Safinamide, which has shown efficacy as an add-on therapy to levodopa in managing motor fluctuations in Parkinson's disease. 2) Opicapone, a COMT inhibitor that helps extend the effect of levodopa. 3) Transdermal rotigotine, which provides continuous dopaminergic stimulation. 4) Deep brain stimulation (DBS), which has been effective in improving motor function and sleep quality in Parkinson's disease. These alternatives offer various mechanisms to manage symptoms and improve quality of life for patients.

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Catechol-O-Methyltransferase (COMT) Inhibitor

Tolcapone for Decision Making

Q: What is the mechanism of action of this treatment?

Common treatments for modulating dopamine levels include levodopa, dopamine agonists, and MAO-B inhibitors. Levodopa is converted to dopamine in the brain, directly increasing dopamine levels and improving motor function in Parkinson's disease. Dopamine agonists mimic dopamine by stimulating dopamine receptors, which can help manage symptoms in both Parkinson's disease and ADHD. MAO-B inhibitors prevent the breakdown of dopamine, thereby increasing its availability. These treatments are crucial as they help manage symptoms related to dopamine deficiency, such as motor dysfunction in Parkinson's disease and attention deficits in ADHD, ultimately improving patients' quality of life and cognitive function.

Phase < 1

Waitlist Available

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

Summary

This trial uses a drug called tolcapone and a special brain scan to study people with social issues related to mental illness. The drug affects a brain chemical called dopamine, which is important for social interactions. The brain scan helps researchers see how the drug changes dopamine levels. Tolcapone has been previously studied for its effects on time perception and dopamine regulation.

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.

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.

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 weeks3 visits

Treatment ~ Varies

Follow Up ~ up to 4 weeks

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

Study objectives can provide a clearer picture of what you can expect from a treatment.

Primary study objectives

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

Psychiatric Hospitalization

Hypertension

Loss of libido

Appetite increase

Concentration impaired

Memory impaired

Rash

Restlessness

Amenorrhea

Cellulitis

Appetite decrease

Hot flashes

Apathy

Akathisia

Dizziness upon standing

Anorgasmia

Drug-related hospitalization

Drug abuse

Blurred vision

Drooling

Sleep disturbed

Medical Hospitalization

Fatigue

Hiccup

Hit by a motorcycle

Hurt when riding a bike

Mental activity decreased

Muscle twitch

Sleeplessness

Pneumonia

Nightmares

Teeth grating

Incarceration

Sensory hallucinations

100%

80%

60%

40%

20%

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

2019

Completed Phase 3

~90

Do I qualify?Apply below to find out

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.

Mechanism Of Action

Side Effect Profile

Prior Approvals

Other Research

Common treatments for modulating dopamine levels include levodopa, dopamine agonists, and MAO-B inhibitors. Levodopa is converted to dopamine in the brain, directly increasing dopamine levels and improving motor function in Parkinson's disease. Dopamine agonists mimic dopamine by stimulating dopamine receptors, which can help manage symptoms in both Parkinson's disease and ADHD. MAO-B inhibitors prevent the breakdown of dopamine, thereby increasing its availability. These treatments are crucial as they help manage symptoms related to dopamine deficiency, such as motor dysfunction in Parkinson's disease and attention deficits in ADHD, ultimately improving patients' quality of life and cognitive function.

Bromocriptine versus levodopa in early Parkinson's disease.