REM Sleep Behavior DisorderPhase 2NCT04386317
Terazosin Effect on Cardiac Changes in Early Parkinson's Disease
A Phase 2 study testing Terazosin in people with REM Sleep Behavior Disorder and Pre-motor Parkinson's Disease, run by Cedars-Sinai Medical Center at 1 site in United States.
Trial summary
Parkinson's disease (PD) is characterized by many non-motor symptoms that occur several years before the diagnosis, in particular idiopathic REM behavior disorder (iRBD), which is associated with autonomic impairment. Read more about this study
- Who is it for?
- Ages 50 to 85 years
- Conditions the study is for
- REM Sleep Behavior Disorder, Pre-motor Parkinson's Disease, Symptomatic Parkinson Disease
- What is being tested?
- Terazosin
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 15 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Nov 2020to 10 Mar 2026
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 to 85 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Male or female of age between 50 and 85 years at time of enrollment.
- Diagnosis of idiopathic REM sleep behavior disorder (iRBD), established either as 'definite RBD' according to the criteria proposed by the International Classification of Sleep Disorders (ICSD)-2 [AASM, 2005] or 'probable RBD' following a score of 6 or higher in the RBD questionnaire (RBDSQ) [Nomura et al, 2011], with a score of at least 1 in subitems 6.1 to 6.4 of question 6 [Halsband et al, 2018].
- At least one of the following:
- Diagnosis of hyposmia, established as a University of Pennsylvania Smell Identification Test (UPSIT) score < 20th percentile for the individual's age group and sex.
- Functional constipation assessed by a scores > 4 on a questionnaire based on modified ROME IV diagnostic criteria.
- Color vision abnormality, as assessed using HRR Pseudoisochromatic Plates, in the absence of congenital dyschromatopsia
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- Symptoms of depression, as assessed by a Beck Depression Inventory (BDI) fast screen score >3 or concurrent use of antidepressant medications.
- Abnormal 123I-MIBG myocardial scintigraphy, as defined by a Late H/M ratio < 2.2 and/or a WR >20%, with normal cardiac ejection fraction (LVEF >55%).
- Capacity to give informed consent
Who cannot join
- Secondary Parkinsonism, including tardive
- Concurrent dementia defined by a score lower than 22 on the MOCA
- Concurrent severe depression defined by a BDI fast screen score greater than 13
- Comorbidites related to SNS hyperactivity
- Heart failure (LVEF< 45%)
- Recent myocardial revascularization (< 12 weeks)
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- Hypertension (SBP >150 mmHg or DBP> 100mmHg)
- Chronic Atrial fibrillation
- Concurrent use of Alpha- adrenergic antagonist
- Diabetes mellitus
- COPD
- Untreated Severe Sleep Apnea; Apnea-Hypopnea Index (AHI) > 30/h.
- Contraindication to the use of Terazosin
- Recent myocardial infarction (< 48 h)
- Ongoing angina pectoris
- Cardiogenic shock or prolonged
- Breast feeding
- Current use of Phosphodiesterase type 5 inhibitors: sildenafil (Viagra TM), tadalafil (Cialis TM), or vardenafil (Levitra TM)
- History of Priapism
- Neurogenic orthostatic hypotensiondefiened as symptomatic decrease in BP> 20 mmHg systolic or > 10mmHg diastolic and HR increase < 20bpm on supine to sitting or standing
- Blood pressure less than 110 mmHG systolic at screening or baseline visit
- Use of investigational drugs whitin 30 days before screening
- For female participant, Pregnacy, or plans for child-bearing during study period
- Allergy/hypersenstivity to iodine or study medication
Trial locations and contacts
1 site in 1 country.
United States1 site
Michele L Lima Gregorio
Los Angeles, California, 90046
About this study
Official title: The Effect of a1- Adrenergic Receptor Antagonist Therapy on Cardiac and Striatal Transporter Uptake in Pre-Motor and Symptomatic Parkinson's Disease
Parkinson's disease (PD) is characterized by many non-motor symptoms that occur several years before the diagnosis, in particular idiopathic REM behavior disorder (iRBD), which is associated with autonomic impairment. The purpose of this study is to investigate the effect of treatment with the selective post-synaptic a1-adrenergic blocker terazosin on 123I-MIBG myocardial uptake in a population of subjects with defined pre-motor PD risks (i.e. hyposmia and RBD) and abnormal baseline 123I-MIBG uptake, with or without 123I-Ioflupane uptake abnormality or PD motor symptoms. Scintigraphic changes will be correlated to motor and non-motor severity of PD, measured by validated clinical scales and cardiac autonomic function tests.
Read the detailed description
Based on the increased risk to develop PD, individuals with iRBD are currently considered ideal candidates for therapies that can possibly protects brain cells, due to the critical window of opportunity to intervene early before brain cell loss progresses significantly.
Early changes of PD are associated with a number of symptoms including loss of smell, constipation, anxiety and depression. In addition, early heart and brain abnormalities can be visualized using specialized imaging techniques called 123I-MIBG myocardial scintigraphy (MIBG) and dopamine transporter (DAT) single photon emission computerized tomography (SPECT) respectively. The combined presence of certain symptoms and the use of these imaging techniques are considered early markers of PD in individuals with iRBD.
In this study the investigators want to learn about the effect of treatment with the adrenergic blocker terazosin on MIBG abnormalities in iRBD patients at risk to develop PD. The investigators believe that reversing the MIBG abnormality might prelude to a slowing of the neurodegenerative process. This drug is approved by the U.S. Food and Drug Administration (FDA) for Benign Prostatic Hyperplasia (BPH) and Hypertension. However, terazosin is not approved by the FDA in patients with iRBD at risk for PD. The available doses for this drug oral formulations are 1mg, 2 mg, 5mg and 10 mg.
Changes visualized with the MIBG imaging technique will be correlated to the presence and severity of neurological (i.e. tremors, stiffness, slow movements, walking difficulties) and other symptoms associated with PD (i.e. abnormal smell, constipation, depression, color vision abnormalities), as measured by specific clinical scales and exams.
- Being tested
- Terazosin
- Medical subject headings
- REM Sleep Behavior Disorder, Parkinson Disease, Secondary
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
TerazosinDrug
Fifteen patients with defined pre-motor PD risk and abnormal baseline 123I-MIBG uptake, with or without 123I-Ioflupane uptake abnormality or PD motor symptoms, will be recruited to receive daily oral doses of terazosin 5 mg or 10 mg. The dosage of terazosin will be gradually increased from the initial recommended starting dose of 1 mg daily at bedtime and titrated stepwise to 2mg, 5mg or 10 mg weekly, according to patient tolerability, as measured by subjective complaints, arterial blood pressure and heart rate. The target dose will be 5 mg or 10 mg daily based on subject's tolerability. Development of incompatibility will be addressed by individually adjusting the dose of terazosin.
| Study group | Role | What they receive |
|---|---|---|
| terazosin therapy | Experimental | Daily oral doses of adrenergic blocker 5 mg or 10 mg. The dosage will be gradually increased from the initial recommended starting dose of 1 mg daily at bedtime and titrated stepwise to 2mg, 5mg or 10 mg weekly, according to patient tolerability, as measured by subjective complaints, arterial blood pressure and heart rate. The target dose will be 5 mg or 10 mg daily based on subject's tolerability. Receives: Drug: Terazosin |
What is being measured
The primary outcome is the main question the study is designed to answer.
Differences in 123I-MIBG reuptake, as measured by early and late Heart to mediastinum (H/M) ratio, and Washout Ration (WR), at 26 weeks of treatment with the adrenergic blocker terazosin
- Differences in 123I-MIBG reuptake, as measured by early and late H/M ratio, and WR, at 26 weeks of treatment with the adrenergic blocker Terazosin.
Measured: At baseline and at 26 weeks after medication titration
Secondary outcomes (3)
Incidence of adverse events
Safety will be monitored collecting the type and frequency of adverse events, including clinical symptoms
Measured: At baseline and at 26 weeks after medication titration
Heart Rate variability changes from baseline at 26 weeks after study medication titration
Beat-to-beat intervals will be registered to assess sympatho-vagal balance.
Measured: At baseline and at 26 weeks after medication titration
Incidence of abnormal vital signs
Changes in vital signs (Blood pressure and Heart rate)
Measured: At baseline and at 26 weeks after medication titration
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 May 2020
- Study start1 Nov 2020
- Primary completion10 Dec 2025
- Study completion10 Mar 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for REM Sleep Behavior DisorderStudies of the same condition, open and under way.
- More trials run by Cedars-Sinai Medical CenterThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 15 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Cedars-Sinai Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Michele Tagliati, MD, Cedars-Sinai Medical Center
- Investigators
- Michele L Tagliati, MD, Principal investigator, Cedars-Sinai Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04386317
- Sponsor's protocol ID
- Study#000540
- Status last verified
- Feb 2026
- First submitted
- 24 Apr 2020
- Last updated
- 2 Mar 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 2 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of a1- Adrenergic Receptor Antagonist Therapy on Cardiac and Striatal Transporter Uptake in Pre-Motor and Symptomatic Parkinson's Disease
- ClinicalTrials.gov ID
- NCT04386317
- Acronym / sponsor ID
- Study#000540
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 15 participants (estimated)
- Lead sponsor
- Cedars-Sinai Medical CenterUniversity, hospital or other
- Study start
- 1 Nov 2020 (actual)
- Primary completion
- 10 Dec 2025 (actual)
- Study completion
- 10 Mar 2026 (estimated)
- First posted
- 13 May 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Parkinson's disease (PD) is characterized by many non-motor symptoms that occur several years before the diagnosis, in particular idiopathic REM behavior disorder (iRBD), which is associated with autonomic impairment. The purpose of this study is to investigate the effect of treatment with the selective post-synaptic a1-adrenergic blocker terazosin on 123I-MIBG myocardial uptake in a population of subjects with defined pre-motor PD risks (i.e. hyposmia and RBD) and abnormal baseline 123I-MIBG uptake, with or without 123I-Ioflupane uptake abnormality or PD motor symptoms. Scintigraphic changes will be correlated to motor and non-motor severity of PD, measured by validated clinical scales and cardiac autonomic function tests.
Detailed description
Based on the increased risk to develop PD, individuals with iRBD are currently considered ideal candidates for therapies that can possibly protects brain cells, due to the critical window of opportunity to intervene early before brain cell loss progresses significantly.
Early changes of PD are associated with a number of symptoms including loss of smell, constipation, anxiety and depression. In addition, early heart and brain abnormalities can be visualized using specialized imaging techniques called 123I-MIBG myocardial scintigraphy (MIBG) and dopamine transporter (DAT) single photon emission computerized tomography (SPECT) respectively. The combined presence of certain symptoms and the use of these imaging techniques are considered early markers of PD in individuals with iRBD.
In this study the investigators want to learn about the effect of treatment with the adrenergic blocker terazosin on MIBG abnormalities in iRBD patients at risk to develop PD. The investigators believe that reversing the MIBG abnormality might prelude to a slowing of the neurodegenerative process. This drug is approved by the U.S. Food and Drug Administration (FDA) for Benign Prostatic Hyperplasia (BPH) and Hypertension. However, terazosin is not approved by the FDA in patients with iRBD at risk for PD. The available doses for this drug oral formulations are 1mg, 2 mg, 5mg and 10 mg.
Changes visualized with the MIBG imaging technique will be correlated to the presence and severity of neurological (i.e. tremors, stiffness, slow movements, walking difficulties) and other symptoms associated with PD (i.e. abnormal smell, constipation, depression, color vision abnormalities), as measured by specific clinical scales and exams.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| terazosin therapy | Experimental | Drug: TerazosinDaily oral doses of adrenergic blocker 5 mg or 10 mg. The dosage will be gradually increased from the initial recommended starting dose of 1 mg daily at bedtime and titrated stepwise to 2mg, 5mg or 10 mg weekly, according to patient tolerability, as measured by subjective complaints, arterial blood pressure and heart rate. The target dose will be 5 mg or 10 mg daily based on subject's tolerability. |
Who may qualify
- Ages
- 50 to 85 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- Male or female of age between 50 and 85 years at time of enrollment.
- Diagnosis of idiopathic REM sleep behavior disorder (iRBD), established either as 'definite RBD' according to the criteria proposed by the International Classification of Sleep Disorders (ICSD)-2 [AASM, 2005] or 'probable RBD' following a score of 6 or higher in the RBD questionnaire (RBDSQ) [Nomura et al, 2011], with a score of at least 1 in subitems 6.1 to 6.4 of question 6 [Halsband et al, 2018].
- At least one of the following:
- Abnormal 123I-MIBG myocardial scintigraphy, as defined by a Late H/M ratio < 2.2 and/or a WR >20%, with normal cardiac ejection fraction (LVEF >55%).
- Capacity to give informed consent
Key exclusion criteria (24 listed)
- Secondary Parkinsonism, including tardive
- Concurrent dementia defined by a score lower than 22 on the MOCA
- Concurrent severe depression defined by a BDI fast screen score greater than 13
- Comorbidites related to SNS hyperactivity
- Contraindication to the use of Terazosin
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| TerazosinFifteen patients with defined pre-motor PD risk and abnormal baseline 123I-MIBG uptake, with or without 123I-Ioflupane uptake abnormality or PD motor symptoms, will be recruited to receive daily oral doses of terazosin 5 mg or 10 mg. The dosage of terazosin will be gradually increased from the initial recommended starting dose of 1 mg daily at bedtime and titrated stepwise to 2mg, 5mg or 10 mg weekly, according to patient tolerability, as measured by subjective complaints, arterial blood pressure and heart rate. The target dose will be 5 mg or 10 mg daily based on subject's tolerability. Development of incompatibility will be addressed by individually adjusting the dose of terazosin. | Drug | terazosin therapy |
Primary outcome
Differences in 123I-MIBG reuptake, as measured by early and late Heart to mediastinum (H/M) ratio, and Washout Ration (WR), at 26 weeks of treatment with the adrenergic blocker terazosin
Time frame: At baseline and at 26 weeks after medication titration
1) Differences in 123I-MIBG reuptake, as measured by early and late H/M ratio, and WR, at 26 weeks of treatment with the adrenergic blocker Terazosin.
3 secondary outcomes
Incidence of adverse events
Time frame: At baseline and at 26 weeks after medication titration
Heart Rate variability changes from baseline at 26 weeks after study medication titration
Time frame: At baseline and at 26 weeks after medication titration
Incidence of abnormal vital signs
Time frame: At baseline and at 26 weeks after medication titration
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Mar 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Michele L Tagliati, MD principal investigator
Cedars-Sinai Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Terazosin in people with REM Sleep Behavior Disorder and Pre-motor Parkinson's Disease, run by Cedars-Sinai Medical Center at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 24 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 2 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Differences in 123I-MIBG reuptake, as measured by early and late Heart to mediastinum (H/M) ratio, and Washout Ration (WR), at 26 weeks of treatment with the adrenergic blocker terazosin (time frame: At baseline and at 26 weeks after medication titration). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Mar 2026.