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Recruiting Phase 2 NCT04186286

NCT04186286 Crossover Study of Propranolol vs Ivabradine in POTS

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Clinical Trial Summary
NCT ID NCT04186286
Status Recruiting
Phase Phase 2
Sponsor University of Calgary
Condition Postural Tachycardia Syndrome
Study Type INTERVENTIONAL
Enrollment 20 participants
Start Date 2021-02-01
Primary Completion 2025-12-31

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age 60 Years
Study Type INTERVENTIONAL
Interventions
Ivabradine 4-week coursePropranolol 4-week coursePlacebo 4-week course

Eligibility Fast-Check

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What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

In Phase 2, researchers evaluate early signs of effectiveness. You may be randomized to receive the active treatment or a comparator. Monitoring continues closely.

This trial targets 20 participants in total. It began in 2021-02-01 with a primary completion date of 2025-12-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

1.0 BACKGROUND Postural tachycardia syndrome (POTS) is a disorder of chronic orthostatic intolerance characterized by symptoms of palpitations, lightheadedness, chest discomfort, shortness of breath, blurred vision, and mental clouding. These symptoms occur during standing and are associated with a marked increase in heart rate (HR) in the absence of hypotension, which typically resolve when sitting or lying down. Most importantly, POTS is associated with a very poor quality of life and significant functional disability. POTS patients commonly experience mental clouding ("brain fog") even while lying down or seated, which poses significant limitations to daily activities . Unfortunately, there is a relative paucity in the literature assessing therapies for POTS patients. Given that excessive tachycardia on standing is a fundamental component of this syndrome, a handful of studies have evaluated medications that reduce HR. Ivabradine is newer drug that is a selective If channel blocker that reduces HR without affecting other cardiovascular functions. 2.0 RATIONALE / STUDY PURPOSE The investigators propose to compare the efficacy of propranolol and ivabradine on HR response to standing, and symptom burden in patients with POTS. 3.0 Study Design This will be a single-center double-blind placebo-controlled randomized crossover trial conducted in patients with POTS to compare effects of (1) oral ivabradine 5 mg bid plus placebo BID (to fill out a QID schedule); (2) oral propranolol 10 mg qid; and (3) oral placebo qid in POTS patients. After a baseline screening assessment following a washout period of 7 days, participants will be randomized to start with a 4-week course of either ivabradine, propranolol or placebo. The other two treatments will be given in separate 4-week courses with a 7-day washout period between phases, with each participant acting as his or her own control. At the end of each 4-week phase, participants will complete the symptom-rating and HRQOL questionnaires, and also undergo tilt table testing to assess the change in HR at 10 min with head up tilt. Participants will undergo POTS testing at baseline and at the end of each 4-week treatment course. This will involve a total of 4 separate study visits.

Eligibility Criteria

Inclusion Criteria: * Diagnosis of Postural Tachycardia Syndrome * Age between 18-60 years * Men and women are eligible * Able and willing to provide informed consent Exclusion Criteria: * Seated resting heart rate \< 70 bpm in the absence of rate-lowering medications * Supine blood pressure \< 90/60 mmHg * Overt cause for postural tachycardia, i.e., acute dehydration, prolonged bed rest * Presence of underlying structural heart disease including: * Valvular disease (i.e. moderate or greater valvular stenosis or regurgitation) * History of heart failure * Greater than mild left ventricular systolic impairment * Hypertrophic cardiomyopathy * Known coronary artery disease or prior myocardial infarction * History of tachyarrhythmias including: * Supraventricular tachycardia, atrial tachycardia, atrial fibrillation / flutter * Ventricular tachyarrhythmias * Pre-existing long QT interval (e.g. known congenital long QT syndrome, or QT interval \>500 ms) * History of sick sinus syndrome or high degree AV block * Presence of a pacemaker, implantable cardioverter defibrillator or cardiac resynchronization therapy device * Diabetes mellitus or history of hypoglycemic episodes * History of bronchospasm or uncontrolled asthma * Pregnant (by history or serum test) or breast-feeding * Inability to safely withdraw from existing beta-blockers or ivabradine prior to the study day * Concomitant use of class I and III antiarrhythmic agents, or non-dihydropyridine calcium channel blockers * Concomitant use of strong cytochrome P450 3A4 (CYP 3A4) inhibitors * Severe hepatic impairment * Any contraindication to propranolol or ivabradine not specifically listed above as per the product monographs. * Unable to give informed consent

Contact & Investigator

Central Contact

Satish Raj, MD

✉ autonomic.research@ucalgary.ca

📞 403-210-6152

Principal Investigator

Satish R Raj, MD

PRINCIPAL INVESTIGATOR

University of Calgary

Frequently Asked Questions

Who can join the NCT04186286 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, up to 60 Years, studying Postural Tachycardia Syndrome. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT04186286 trial and what does that mean for participants?

Phase 2 trials evaluate whether the treatment shows signs of effectiveness while continuing to monitor safety. More participants are enrolled than in Phase 1 to help refine the treatment protocol.

Is NCT04186286 currently recruiting?

Yes, NCT04186286 is actively recruiting participants. Contact the research team at autonomic.research@ucalgary.ca for enrollment information.

Where is the NCT04186286 trial being conducted?

This trial is being conducted at Calgary, Canada.

Who is sponsoring the NCT04186286 clinical trial?

NCT04186286 is sponsored by University of Calgary. The principal investigator is Satish R Raj, MD at University of Calgary. The trial plans to enroll 20 participants.

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