What side effects are associated with this type of intervention?

Common treatments for Parkinson's Disease include levodopa, dopamine agonists, and cholinesterase inhibitors. Levodopa can cause nausea, somnolence, dizziness, headache, confusion, hallucinations, delusions, agitation, psychosis, and orthostatic hypotension. Dopamine agonists may lead to similar side effects and also compulsive behaviors. Cholinesterase inhibitors, used for cognitive impairment in PD, can worsen tremor and cause nausea. Terazosin, a selective post-synaptic a1-adrenergic blocker, is being studied for its long-term effects on motor and non-motor symptoms in PD, but specific side effects in this context are not detailed.

What prior FDA approvals exist?

The FDA has approved several drugs for the treatment of Parkinson's Disease, focusing on different mechanisms to manage symptoms. These include VMAT2 inhibitors like tetrabenazine and deutetrabenazine, which are used for chorea associated with Huntington's Disease but have implications for movement disorders in PD. Dopamine agonists and MAO B inhibitors are commonly used to enhance dopaminergic activity. Amantadine is another option, particularly useful for managing tremor. While terazosin, a selective post-synaptic a1-adrenergic blocker, is being studied for its long-term effects on PD, similar alpha-adrenergic receptor blockers like prazosin have been used to manage related symptoms such as sleep disturbances in PTSD, indicating a potential therapeutic overlap.

What other types of research exist?

Promising novel alternatives to Terazosin for Parkinson's Disease patients include new quinazoline derivatives and pyridopyrimidine compounds, which have shown higher potency and efficacy in preclinical studies.

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Alpha-1 Adrenergic Blocker

Terazosin Therapy for Parkinson's Disease

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

The most common treatments for Parkinson's Disease (PD) work by addressing the dopamine deficiency characteristic of the condition. Levodopa, often combined with carbidopa, is converted to dopamine in the brain, directly replenishing dopamine levels. Dopamine agonists, such as pramipexole and ropinirole, mimic dopamine by stimulating dopamine receptors. MAO-B inhibitors, like selegiline and rasagiline, prevent the breakdown of dopamine, thereby increasing its availability. Anticholinergics, such as trihexyphenidyl, help reduce tremors by blocking acetylcholine. Terazosin, a selective post-synaptic a1-adrenergic blocker, is being studied for its potential neuroprotective effects, which may offer additional benefits beyond symptom management. Understanding these mechanisms allows for more personalized and effective treatment strategies for PD patients.

Phase 2

Recruiting

Led By Michele Tagliati, MD, FAAN

Research Sponsored by Cedars-Sinai Medical Center

Eligibility Criteria Checklist

Specific guidelines that determine who can or cannot participate in a clinical trial

Must have

Capacity to give informed consent

Be older than 18 years old

Must not have

Contraindications to the use of terazosin

For female participant, pregnancy, or plans for child-bearing during study period

Timeline

Screening 3 weeks

Treatment Varies

Follow Up 3 years

Awards & highlights

No Placebo-Only Group

Summary

This trial is testing terazosin, a medication that helps relax muscles and improve blood flow, on people with early signs of Parkinson's disease risks. The goal is to see if it can slow down or prevent the progression of the disease. Terazosin and similar drugs were recently found to enhance energy production and reduce Parkinson's disease progression in animal studies and human data.

Who is the study for?

This trial is for people who were part of a previous Parkinson's study, can consent, and don't have conditions like secondary Parkinsonism, dementia, severe depression, recent heart issues or certain other health problems. It's not for those with low blood pressure, untreated sleep apnea, heart failure or kidney issues.

What is being tested?

The study tests the long-term effects of Terazosin on people at risk for pre-motor Parkinson's disease. Researchers will look at brain imaging changes and compare them to motor and non-motor symptoms as well as cardiac function over time.

What are the potential side effects?

While specific side effects are not listed here, Terazosin may cause dizziness due to its blood pressure-lowering effect. Other common side effects could include weakness or nasal congestion.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below

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I understand the details of the clinical trial and can consent to participate.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:

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I have no health issues that prevent me from taking terazosin.

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I am not pregnant and do not plan to become pregnant during the study.

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I have diabetes.

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I have had a severe heart condition causing very low blood pressure.

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I have Parkinson's disease symptoms not caused by primary Parkinson's.

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My heart's pumping ability is reduced (LVEF <45%).

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I have chronic atrial fibrillation.

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I experience significant drops in blood pressure with little change in heart rate when standing.

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I am currently taking beta-blocker medication.

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My kidney function is severely reduced.

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I have severe sleep apnea that hasn't been treated.

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I am currently taking medication like Viagra, Cialis, or Levitra.

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I am allergic to iodine or the medication used in this study.

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I have health issues related to an overactive nervous system.

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I have been diagnosed with COPD.

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I have not had a heart attack in the last 48 hours.

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I experience ongoing chest pain.

Timeline

Screening ~ 3 weeks3 visits

Treatment ~ Varies

Follow Up ~ every year for three years

Screening ~ 3 weeks

Treatment ~ Varies

Follow Up ~every year for three years

This trial's timeline: 3 weeks for screening, Varies for treatment, and every year for three years for reporting.

Treatment Details

Study Objectives

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

Primary study objectives

Changes in 123I-MIBG - Washout ratio (WR)

Changes in 123I-MIBG reuptake - early Heart to Mediastinal ratio (H/M)

Changes in 123I-MIBG reuptake - late Heart to Mediastinal ratio (H/M)

Secondary study objectives

Changes in 123I-Ioflupane uptake

Diagnosis of PD or other synucleinopathies by the end of 3 years in the study population

Heart Rate Variability Analysis (HRV) compared to MIBG results in predicting RBD conversion to PD/other synucleinopathies

+1 more

Other study objectives

Central insulin resistance changes between baseline and every 6 months for three years

Color vision changes, as assessed using Hardy, Rand and Rittler (HRR) pseudoisochromatic Plates, between baseline and every 6 months for three years

Correlation between changes in integrity of pigmented neurons of substantia nigra as measured by neuromelanin-sensitive magnetic resonance imaging (MRI) and 123I-Ioflupane uptake as measured by Dopamine Transporter Imaging (DAT scan)

+9 more

Awards & Highlights

No Placebo-Only Group

All patients enrolled in this study will receive some form of active treatment.

Trial Design

1Treatment groups

Experimental Treatment

Group I: terazosin therapy extensionExperimental Treatment1 Intervention

Primary procedures in this study are MIBG scan, DAT scan, NM-MRI, and terazosin medication. Subjects will return for research visits and imaging every six months for three years. The investigators hypothesize that the rate of decline in DAT scan123I-Ioflupane uptake will be slower in subjects who have received the alpha1- adrenergic receptor antagonist terazosin, resulting in a decreased clinical conversion rate to parkinsonism.

0 / 18Eligibility criteria met

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

The most common treatments for Parkinson's Disease (PD) work by addressing the dopamine deficiency characteristic of the condition. Levodopa, often combined with carbidopa, is converted to dopamine in the brain, directly replenishing dopamine levels. Dopamine agonists, such as pramipexole and ropinirole, mimic dopamine by stimulating dopamine receptors. MAO-B inhibitors, like selegiline and rasagiline, prevent the breakdown of dopamine, thereby increasing its availability. Anticholinergics, such as trihexyphenidyl, help reduce tremors by blocking acetylcholine. Terazosin, a selective post-synaptic a1-adrenergic blocker, is being studied for its potential neuroprotective effects, which may offer additional benefits beyond symptom management. Understanding these mechanisms allows for more personalized and effective treatment strategies for PD patients.

Pharmacologic approaches to the treatment of Huntington's disease.Noradrenergic drugs for levodopa-induced dyskinesia.