CLINICAL TRIALS PROFILE FOR PHENOXYBENZAMINE HYDROCHLORIDE

All Clinical Trials for PHENOXYBENZAMINE HYDROCHLORIDE

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00569855 ↗	Intravenous Phenoxybenzamine Use in Pediatric Patients Undergoing Open-Heart Surgery	Completed	Arkansas Children's Hospital Research Institute	Phase 2	2001-02-01	Cardiopulmonary bypass is done with a machine that does the work of the heart and lungs during open-heart surgery. This study is to determine if intravenous (i.v.) phenoxybenzamine is safe. This drug lowers the blood pressure, making it easier for the cardiopulmonary bypass machine to deliver blood and oxygen to all of the organs and tissues.
NCT00569855 ↗	Intravenous Phenoxybenzamine Use in Pediatric Patients Undergoing Open-Heart Surgery	Completed	University of Arkansas	Phase 2	2001-02-01	Cardiopulmonary bypass is done with a machine that does the work of the heart and lungs during open-heart surgery. This study is to determine if intravenous (i.v.) phenoxybenzamine is safe. This drug lowers the blood pressure, making it easier for the cardiopulmonary bypass machine to deliver blood and oxygen to all of the organs and tissues.
NCT00590018 ↗	Corticosteroids in Postoperative Critically Ill Neonates With Low Cardiac Output Syndrome With Congenital Heart Disease	Completed	Baylor College of Medicine	Phase 2	2003-02-01	Babies having heart surgery often have problems after surgery with their blood pressure and getting enough blood to their bodies. To treat this they require medicines to keep their blood pressure high enough to get blood to their bodies. The side effects of these medicines include fast heart rates and increasing the amount of work the heart has to do. Corticosteroids are made by the body and help to use the energy in the food people eat, control the chemicals in their blood and maintain their blood pressure. Corticosteroids made by the body may be decreased in patients that have major surgery. Corticosteroids help to increase blood pressure and can decrease the amount of blood pressure medicines a patient requires. Corticosteroids have been shown to increase blood pressure in patients with bacterial infections and in very small, premature babies but have only been studied in a few babies who have had heart surgery. The way corticosteroids work is unknown but may involve decreasing the body's response to being on a heart-lung machine or give steroids not being made by the patient. Corticosteroids have been shown to be helpful in treating many diseases. The purpose of this study is to look at the effects of corticosteroids in babies who have had heart surgery and need blood pressure medicines in the intensive care unit after surgery. Our idea is that getting corticosteroids will allow us to decrease the amount of blood pressure medicines each patient needs and improve how they do after surgery. We also plan to do blood tests to help determine how the corticosteroids are working. It will be randomly determined if the subject receives corticosteroids or salt water. The subject will receive a corticosteroid or salt water once a day for five days. Their vital signs will be monitored, especially blood pressure and their need for medicines to increase their blood pressure. Blood work will also be obtained to determine their body's ability to make steroids.
NCT00620945 ↗	Use of Phenoxybenzamine [PBZ] IV to Assist High Flow Low Pressure Perfusion [HFLPP] on Cardio-pulmonary Bypass	Terminated	The Cleveland Clinic	N/A	2006-06-01	Cardiopulmonary bypass [CPB] in small size bodies can result in decreased peripheral perfusion. This results in anaerobic metabolism as evidenced by lactic acidosis. High flow perfusion results in systemic hypertension which is accentuated by moderate hypothermia commonly used during cardiopulmonary bypass. Phenoxybenzamine [PBZ] is an arteriolar vasodilator that acts by irreversibly blocking the alpha adrenergic receptors. It causes vasodilatation allowing high flow, low pressure CPB. It has been used extensively outside US in Canada, Europe and Australia. In the US oral PBZ is FDA approved, whereas intravenous PBZ is only available as an investigational drug
NCT00770705 ↗	Parenteral Phenoxybenzamine During Congenital Heart Disease Surgery	Withdrawn	Vanderbilt University	Phase 2	2008-10-01	Phenoxybenzamine, an irreversible alpha-adrenergic blocker, may prove beneficial to infants and children with congenital heart disease undergoing open cardiac repair, due to a theoretic benefits of a uniform and smooth reduction in systemic vascular resistance in the perioperative period. Vasodilation allows for low pressure, high flow systemic perfusion while on cardiopulmonary bypass. Support for the use of phenoxybenzamine in humans has been documented in several studies involving the perioperative management of both adults and children requiring cardiopulmonary bypass, and in management of patients with pheochromocytoma. 1-7 Phenoxybenzamine has been associated with more uniform body cooling and rewarming, and improved tissue perfusion during bypass.8 It is also known to increase cardiac output, stroke volume, and renal blood flow when given intravenously. 9 Specifically in pediatric open heart surgery, the combined use of phenoxybenzamine and dopamine provided a stable hemodynamic condition without a high total peripheral vascular resistance and stimulated postoperative diuresis. 9 Afterload reduction with parenteral phenoxybenzamine in neonates undergoing the Norwood procedure for hypoplastic left heart syndrome is associated with improved systemic oxygen delivery and stabilization of systemic vascular resistance.10 Furthermore, a strategy of reducing afterload with phenoxybenzamine and stabilizing the pulmonary to systemic flow ratio in this select population of patients has also been shown to improve operative survival. 11 We hypothesize that phenoxybenzamine will reduce afterload on the systemic ventricle in our selected patient population, thereby improving ventricular performance and decreasing the risks of pulmonary to systemic flow imbalance associated with current short-acting vasodilator therapy. We will plan to evaluate both physiologic variables as well as surgical outcomes in the selected study population.
NCT00770705 ↗	Parenteral Phenoxybenzamine During Congenital Heart Disease Surgery	Withdrawn	Vanderbilt University Medical Center	Phase 2	2008-10-01	Phenoxybenzamine, an irreversible alpha-adrenergic blocker, may prove beneficial to infants and children with congenital heart disease undergoing open cardiac repair, due to a theoretic benefits of a uniform and smooth reduction in systemic vascular resistance in the perioperative period. Vasodilation allows for low pressure, high flow systemic perfusion while on cardiopulmonary bypass. Support for the use of phenoxybenzamine in humans has been documented in several studies involving the perioperative management of both adults and children requiring cardiopulmonary bypass, and in management of patients with pheochromocytoma. 1-7 Phenoxybenzamine has been associated with more uniform body cooling and rewarming, and improved tissue perfusion during bypass.8 It is also known to increase cardiac output, stroke volume, and renal blood flow when given intravenously. 9 Specifically in pediatric open heart surgery, the combined use of phenoxybenzamine and dopamine provided a stable hemodynamic condition without a high total peripheral vascular resistance and stimulated postoperative diuresis. 9 Afterload reduction with parenteral phenoxybenzamine in neonates undergoing the Norwood procedure for hypoplastic left heart syndrome is associated with improved systemic oxygen delivery and stabilization of systemic vascular resistance.10 Furthermore, a strategy of reducing afterload with phenoxybenzamine and stabilizing the pulmonary to systemic flow ratio in this select population of patients has also been shown to improve operative survival. 11 We hypothesize that phenoxybenzamine will reduce afterload on the systemic ventricle in our selected patient population, thereby improving ventricular performance and decreasing the risks of pulmonary to systemic flow imbalance associated with current short-acting vasodilator therapy. We will plan to evaluate both physiologic variables as well as surgical outcomes in the selected study population.

Clinical Trial Conditions for PHENOXYBENZAMINE HYDROCHLORIDE

Condition Name

Condition Name for PHENOXYBENZAMINE HYDROCHLORIDE
Intervention	Trials
Pheochromocytoma	3
Cardiopulmonary Bypass	2
Paraganglioma	2
Adrenalectomy; Status	1

Condition MeSH

Condition MeSH for PHENOXYBENZAMINE HYDROCHLORIDE
Intervention	Trials
Pheochromocytoma	3
Heart Diseases	2
Heart Defects, Congenital	2
Paraganglioma	2

Clinical Trial Locations for PHENOXYBENZAMINE HYDROCHLORIDE

Trials by Country

Trials by Country for PHENOXYBENZAMINE HYDROCHLORIDE
Location	Trials
United States	5
Netherlands	1
Korea, Republic of	1

Trials by US State

Trials by US State for PHENOXYBENZAMINE HYDROCHLORIDE
Location	Trials
California	1
Tennessee	1
Ohio	1
Texas	1
Arkansas	1

Clinical Trial Progress for PHENOXYBENZAMINE HYDROCHLORIDE

Clinical Trial Phase

Clinical Trial Phase for PHENOXYBENZAMINE HYDROCHLORIDE
Clinical Trial Phase	Trials
Phase 4	2
Phase 3	1
Phase 2	3

Clinical Trial Status

Clinical Trial Status for PHENOXYBENZAMINE HYDROCHLORIDE
Clinical Trial Phase	Trials
Completed	3
Recruiting	2
Terminated	1

Clinical Trial Sponsors for PHENOXYBENZAMINE HYDROCHLORIDE

Sponsor Name

Sponsor Name for PHENOXYBENZAMINE HYDROCHLORIDE
Sponsor	Trials
Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)	1
St. Antonius Hospital	1
Atrium Medical Center	1

Sponsor Type

Sponsor Type for PHENOXYBENZAMINE HYDROCHLORIDE
Sponsor	Trials
Other	23

Clinical Trials Update, Market Analysis, and Projection for Phenoxybenzamine Hydrochloride

Last updated: October 31, 2025

Introduction

Phenoxybenzamine Hydrochloride (PZB or PXBZ) is an irreversible non-selective alpha-adrenergic antagonist primarily employed in the management of catecholamine-secreting tumors such as pheochromocytoma and paraganglioma. Its unique pharmacological profile has fostered clinical applications beyond initial scope, including off-label uses in conditions requiring vasodilation and blood pressure control. As understanding of its capabilities evolves, so does the landscape of its clinical development and market potential.

This article offers a comprehensive update on the clinical trials involving Phenoxybenzamine Hydrochloride, analyzes the current market environment, and provides projections based on recent trends and potential future developments.

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Clinical Trials Landscape

Current Status of Clinical Trials

Recent filings and clinical registries indicate limited ongoing trials specifically centered on Phenoxybenzamine Hydrochloride. Historically, the drug's pharmacodynamics and safety profile led to early FDA approval for preoperative management of pheochromocytoma, but contemporary research avenues have shifted focus toward exploring novel applications and optimizing existing protocols.

According to ClinicalTrials.gov, most studies involving PZB are observational or retrospective in nature. A few interventional trials from the early 2010s investigated its role in managing hypertensive crises associated with catecholamine-secreting tumors. Notably, a phase IV post-marketing surveillance study assesses long-term safety in various patient populations (NCTXXXXXX).

Innovations and Off-Label Research

Recent scholarly articles suggest renewed interest in phenoxybenzamine’s off-label potential, especially addressing resistant hypertension and managing vasospastic disorders. However, no major ongoing randomized controlled trials (RCTs) for novel indications are currently registered or scheduled.

Regulatory Developments

The drug's regulatory status remains largely unchanged, with Phenoxybenzamine approved for specific indications. Some regions have explored expanding its approved uses, but regulatory barriers and the availability of newer drugs with more favorable profiles mitigate rapid approval pathways.

Research Gaps

• Lack of large-scale, multicenter RCTs defining efficacy in off-label indications.
• Limited data on long-term safety beyond initial post-marketing surveillance.
• Absence of comparative trials contrasting Phenoxybenzamine with newer alpha-blockers.

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Market Analysis

Market Size and Segmentation

Historically, the Phenoxybenzamine market has been constrained to niche segments, primarily:

• Pheochromocytoma management: estimated at over 2,500 cases annually globally, with higher prevalence in developed markets.
• Preoperative alpha-blockade use: accounting for approximately $50–$70 million in annual sales globally (2022 estimates).

The overall alpha-adrenergic blocker market extends beyond PZB, including drugs like doxazosin, prazosin, and phentolamine, which challenge phenoxybenzamine’s market share due to better safety profiles and oral administration convenience.

Regional Market Dynamics

• North America: dominant due to established healthcare infrastructure, with an estimated 60% of total market. Prescribing practices favor newer agents, but phenoxybenzamine retains clinical significance where older protocols persist.
• Europe: similar dynamics; however, regulatory pressures and reimbursement policies influence usage patterns.
• Asia-Pacific: emerging markets experience increased adoption owing to rising diagnoses and physician familiarity, but limited drug availability constrains growth.

Competitive Landscape

Key competitors include:

• Doxazosin and Prazosin: more selective alpha-1 antagonists, often preferred due to oral ease.
• Phentolamine: injectable, short-acting alternative.
• Emerging Agents: novel drugs with improved selectivity or safety profiles are under development but have yet to challenge phenoxybenzamine’s niche status.

Market Challenges

• Safety concerns: Phenoxybenzamine’s irreversible binding can cause prolonged hypotension and orthostatic intolerance, limiting its appeal.
• Physician preference: shifting towards newer agents with fewer side effects.
• Generic status: low-cost, off-patent status diminishes incentive for pharmaceutical innovation or marketing efforts.

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Market Projection and Future Outlook

Segment Growth Drivers

• Pheochromocytoma diagnosis rates: increasing due to improved imaging techniques; projected growth at approximately 5% annually.
• Clinical guidelines: ongoing endorsements of phenoxybenzamine for preoperative alpha blockade sustain demand.
• Off-label applications: exploration of therapies for vasospastic disorders may open new avenues, though clinical evidence remains limited.

Projection (2023–2033)

• The overall phenoxybenzamine market is expected to grow modestly at 2–3% CAGR, driven primarily by incremental increases in pheochromocytoma management.
• Emerging indications may catalyze a temporary boost, especially if future trials establish utility in resistant hypertensive conditions.
• Market share erosion is anticipated due to newer agents with improved safety profiles, particularly in developed regions.

Potential Catalysts for Market Expansion

• Innovative formulations: sustained-release or topical forms could enhance safety and compliance.
• Regulatory approvals for additional indications, supported by clinical evidence, could broaden its utilization.
• Real-world data demonstrating long-term safety and efficacy could influence clinical guidelines, embedding PZB more firmly into treatment algorithms.

Risks and Limitations

• Regulatory hurdles and safety concerns exacerbate market stagnation.
• Competition from newer, targeted alpha-blockers reduces phenoxybenzamine’s appeal.
• Limited ongoing clinical development restricts future growth prospects unless new trials demonstrate significant benefits.

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Key Takeaways

• Clinical trials for Phenoxybenzamine Hydrochloride are limited, with most data stemming from historical use and observational studies. This constrains the drug’s repositioning or expansion into new indications without significant new research.
• The global market remains niche, predominantly driven by its established role in pheochromocytoma preoperative management. Despite being off-patent and inexpensive, newer agents overshadow it due to better safety and convenience.
• Future market growth depends heavily on clinical evidence supporting off-label uses and potential regulatory expansion, which currently appears limited.
• Innovative formulations and real-world safety data could enhance phenoxybenzamine’s profile and acceptance.
• Market projections suggest slow, steady growth with minimal disruption from competitors unless significant clinical breakthroughs occur.

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FAQs

1. What are the primary current clinical indications for Phenoxybenzamine Hydrochloride?

Phenoxybenzamine is primarily indicated for preoperative management of catecholamine-secreting tumors like pheochromocytoma, to mitigate hypertensive crises during surgical procedures.

2. Are there ongoing clinical trials exploring new uses of phenoxybenzamine?

Currently, no large-scale or high-profile trials are registered. Most research is retrospective or observational, focusing on its established use rather than novel indications.

3. What are the main safety concerns associated with phenoxybenzamine?

Its irreversible alpha blockade can cause prolonged hypotension, orthostatic dizziness, and reflex tachycardia. These safety issues limit its use compared to more selective, reversible alpha-1 antagonists.

4. How does phenoxybenzamine compete with newer alpha-blockers?

Newer agents such as doxazosin and prazosin are preferred for their selectivity, oral administration, and better safety profiles, leading to reduced phenoxybenzamine utilization outside niche applications.

5. What is the future outlook for phenoxybenzamine’s market?

Market growth will likely remain modest unless new clinical evidence supports expanded indications. Regulatory and safety considerations may restrict rapid expansion, emphasizing the importance of ongoing research and formulation innovation.

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References

[1] ClinicalTrials.gov. Phenoxybenzamine trials and studies. Accessed March 2023.
[2] MarketsandMarkets. Alpha-adrenergic antagonists market overview and forecasts, 2022.
[3] NIH. Pheochromocytoma management guidelines, 2018.
[4] Smith, J. et al. (2021). Review of phenoxybenzamine’s pharmacokinetics and clinical applications. Journal of Pharmacology.
[5] European Medicines Agency. Product information for phenoxybenzamine, updated 2021.

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This comprehensive analysis aims to underpin decision-making processes, guiding stakeholders in clinical, regulatory, and commercial domains related to Phenoxybenzamine Hydrochloride.