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
Paraganglioma	2
Cardiopulmonary Bypass	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
Korea, Republic of	1
Netherlands	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
Withdrawn	1

Clinical Trial Sponsors for PHENOXYBENZAMINE HYDROCHLORIDE

Sponsor Name

Sponsor Name for PHENOXYBENZAMINE HYDROCHLORIDE
Sponsor	Trials
Maxima Medical Center	1
The Cleveland Clinic	1
Medisch Spectrum Twente	1

Sponsor Type

Sponsor Type for PHENOXYBENZAMINE HYDROCHLORIDE
Sponsor	Trials
Other	23

Last updated: May 6, 2026

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

Phenoxybenzamine hydrochloride is an oral nonselective alpha-adrenergic blocker used off-label and under limited indications in practice for conditions such as pheochromocytoma or paraganglioma (preoperative control) and severe hypertension due to catecholamine excess. The available public clinical-trial footprint for phenoxybenzamine is sparse and not current enough to support a modern, drug-development calendar update at product level. The commercial market is therefore best modeled as a niche, mostly supply-driven generics and legacy-brand lifecycle, with demand tied to surgical oncology/endocrinology workflows and intermittent guideline use rather than a sustained, large late-stage pipeline.

What does the current clinical-trial landscape look like?

Publicly searchable clinical-trial records for phenoxybenzamine hydrochloride show limited contemporary activity. The drug is historically used, so the observable trial record tends to include older studies, small cohorts, and trials that are not focused on phenoxybenzamine as a modern development candidate (for example, studies that evaluate alpha blockade strategies broadly or compare perioperative hemodynamic regimens).

Because phenoxybenzamine is an established therapy, the more decision-relevant “update” is regulatory-and-evidence status: whether new efficacy or safety evidence is being actively generated, and whether dosing formulations or route changes are under study. In the public record, that activity is limited.

Clinical-trial activity signals (public registries):

• No clear pattern of late-stage (Phase 3) modernization studies for phenoxybenzamine hydrochloride as a dedicated development program.
• Low visibility of active recruiting or recently completed trials specifically naming phenoxybenzamine hydrochloride as the investigational medicinal product in a contemporary development context.
• Trial reports, where they exist, skew toward perioperative hemodynamic control or historical alpha-blockade practice rather than new label expansion.

Where evidence is anchored

• Clinical use and perioperative alpha blockade protocols for pheochromocytoma/paraganglioma still depend heavily on established practice and older evidence rather than continuous large-scale trial generation. Reference text and guidance commonly emphasize alpha blockade with phenoxybenzamine (or alternative agents such as doxazosin) as part of preoperative management workflows (evidence bases vary by jurisdiction and year). Phenoxybenzamine remains present as a named option in many clinical algorithms rather than a pipeline candidate.

Primary take: For near-term R&D or commercialization planning, phenoxybenzamine should be treated as a legacy molecule with clinical demand tied to routine perioperative practice, not as a product where incremental trials are likely to unlock broad new market segments.

Evidence sources used for clinical positioning

• Clinical practice around pheochromocytoma/paraganglioma management relies on alpha blockade; modern reviews and guidelines continue to reference phenoxybenzamine as a classic option for preoperative control and hemodynamic stabilization. (See citations [1], [2].)
• Registry-level visibility for phenoxybenzamine-specific trials is low compared with drugs that have active Phase 2/3 programs.

What is the market basis for demand and who buys?

The phenoxybenzamine market is driven by a mix of:

1. Surgical oncology/endocrinology demand (patients with pheochromocytoma/paraganglioma undergoing planned resection)
2. Emergency and perioperative stabilization workflows when catecholamine excess syndromes require preoperative or bridging alpha blockade
3. Legacy generics supply with pricing and availability shaping usable inventory

Customer segments

• Tertiary centers performing endocrine tumor surgery (high surgical volume and perioperative ICU involvement).
• Hospitals and networks with endocrine tumor boards and standardized preoperative protocols.
• Compounding and pharmacy systems where shortages or formulation availability can shift procurement decisions.

Formulation and route

• Phenoxybenzamine hydrochloride is supplied primarily as an oral medication. Demand depends on local generic availability and adherence to established dosing titration protocols used in preoperative management.

How large is the market and what drives growth vs. decline?

A quantified global market size cannot be derived solely from open public sources in a way that would meet a business-grade standard for projection. The drug is niche and the commercial data is fragmented across generics and private procurement, which makes robust market-size extraction unreliable without paid datasets.

A more decision-relevant approach is to model market direction using structural drivers:

Demand drivers

• Incidence of pheochromocytoma/paraganglioma and referral patterns: demand is linked to surgical detection and referral volume.
• Protocol persistence: many institutions still keep phenoxybenzamine in their preoperative options, even as doxazosin has gained favor in some guidelines.
• Perioperative hemodynamic needs: alpha blockade remains standard; where phenoxybenzamine has historical institutional preference, usage persists.

Supply and pricing constraints

• Generic lifecycle dynamics: market value is often constrained by generic competition rather than by brand premium.
• Manufacturing continuity: small-molecule generics can face intermittent supply constraints, which can temporarily lift pricing and increase purchasing friction.

Competitive substitution

• Doxazosin and other alpha-1 selective blockers have taken share in some settings, supported by some guideline positions and clinical practice trends favoring alternatives due to tolerability considerations. Phenoxybenzamine still maintains use where institutional protocols prefer it or where prior experience exists. (See [1], [2].)

What is the most defensible market projection?

Given the lack of an active modern clinical pipeline and the drug’s legacy status, the market projection should focus on utilization trend and supply-price behavior, not label-expansion-driven growth.

Base-case projection framework (directional, not speculative):

• Near-term (1-3 years): stable to slightly downward utilization share as alternative alpha blockers remain preferred in some protocols; total category volumes track surgical detection and referral patterns.
• Mid-term (3-7 years): gradual stabilization if phenoxybenzamine remains an institutional option, with pricing variability reflecting generic supply continuity.
• Long-term (7-10 years): modest contraction risk remains due to:
  • continued preference shifts to alternatives
  • generics substitution dynamics
  • reduced emphasis on older nonselective alpha blockade in new protocols, depending on national guideline uptake.

Investment/R&D implication

• For investors, the most material upside is not new evidence-driven expansion. It is commercial execution and supply stability (contracting, formulary position, inventory planning).
• For R&D, value creation would likely require a formulation or access strategy rather than expecting a label expansion supported by large new trials, given low contemporary clinical-trial visibility.

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Competitive and Evidence Context

How does phenoxybenzamine fit against alternative alpha blockers?

Many current management pathways for pheochromocytoma/paraganglioma still describe alpha blockade as required preoperatively. They often include phenoxybenzamine as an option, while alternative agents like doxazosin can be used depending on local practice, adverse-effect profile, and hemodynamic targets. (See [1], [2].)

Business impact of substitution

• If a hospital protocol updates to prefer a different agent, phenoxybenzamine demand can drop quickly even when the overall alpha-blockade requirement remains unchanged.
• Conversely, where protocols are conservative or where phenoxybenzamine is entrenched, demand remains “sticky” even as broader practice shifts elsewhere.

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Supply Chain and Product Strategy Considerations

What matters for commercial outcomes in a niche legacy drug?

In small-niche generics, operational reliability often dominates brand-level marketing.

Key levers:

• Availability and fill-rate: shortage events cause stockouts and protocol reversion to alternatives.
• Pricing strategy: procurement tends to be driven by formulary approvals and contract pricing.
• Distribution depth: tertiary centers and large hospital networks may require consistent stocking to keep phenoxybenzamine as an active option.

Because clinical-trial momentum is limited, these levers represent the primary determinant of near-term revenue performance.

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Key Takeaways

1. Clinical-trial modernization for phenoxybenzamine hydrochloride is limited; the drug’s public development activity is sparse, so the evidence base relies on established, older clinical practice rather than active Phase 2/3 expansion.
2. Market demand is driven by surgical workflows for pheochromocytoma/paraganglioma and institutional preoperative protocols, not by new label-changing trials.
3. Growth is constrained by substitution toward other alpha blockers in some protocols, while revenue is stabilized by continued niche usage and generic supply behavior.
4. Best projection strategy treats phenoxybenzamine as a legacy, supply- and formulary-position-driven asset with stable to modest decline risk rather than a pipeline-led growth story.

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FAQs

1) Is phenoxybenzamine hydrochloride currently supported by active Phase 3 trials?

Public clinical-trial visibility is low and does not show a clear, contemporary Phase 3 development program specifically for phenoxybenzamine hydrochloride.

2) What clinical use most strongly supports ongoing demand?

Preoperative alpha blockade in patients with pheochromocytoma/paraganglioma undergoing surgical resection remains the dominant demand anchor in practice. [1], [2]

3) What drives substitution away from phenoxybenzamine?

Protocol preference shifts to alternative alpha blockers (commonly doxazosin) can reduce phenoxybenzamine utilization share even while the overall need for alpha blockade persists. [1], [2]

4) How should market projection be modeled for a legacy generic?

Model utilization trends tied to endocrine tumor surgery volumes and institutional protocol persistence, then overlay supply and generic pricing behavior.

5) Where can value be created commercially if clinical trials are limited?

Value creation is most likely through supply continuity, contracting and formulary positioning at tertiary centers, and maintaining inventory to prevent protocol drift during shortages.

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References

[1] Ilias, I., et al. (2016). Pheochromocytoma and paraganglioma: An update on the diagnosis and management. Endocrine Reviews, 37(2), 146-192.
[2] Pacak, K., et al. (2013). Pheochromocytoma and paraganglioma: A modern approach. Endocrine-Related Cancer, 20(3), R357-R372.