CLINICAL TRIALS PROFILE FOR AMILORIDE HYDROCHLORIDE

505(b)(2) Clinical Trials for amiloride hydrochloride

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
New Combination	NCT00590538 ↗	Phenylbutyrate/Genistein Duotherapy in Delta F508-Heterozygotes (for Cystic Fibrosis)	Terminated	Cystic Fibrosis Foundation	Phase 1/Phase 2	2003-02-01	The purpose of this research study is to test a new combination of medicines, Phenylbutyrate and Genistein, to determine if they could be used to treat cystic fibrosis (CF). The most common genetic mutation found in patients with CF is called Delta F508. Due to this mutation, there is a lack of salt (chloride) movement in your nose, sinuses, lungs, intestines, pancreas and sweat glands. This lack of movement causes the clinical manifestations of the disease. Although Phenylbutyrate has been extensively used to treat patients with rare metabolic diseases, Phenylbutyrate is an investigational drug for the purpose of this study. Genistein is a naturally occurring substance that is found in food products such as soy and tofu, but is also an investigational drug for this study. When used together, both drugs may be able to restore normal chloride and salt (water) movements in body organs and glands in people with CF. We will be studying salt and water movement in the nose by a technique called nasal transepithelial potential difference (NPD).
New Combination	NCT00590538 ↗	Phenylbutyrate/Genistein Duotherapy in Delta F508-Heterozygotes (for Cystic Fibrosis)	Terminated	Cystic Fibrosis Foundation Therapeutics	Phase 1/Phase 2	2003-02-01	The purpose of this research study is to test a new combination of medicines, Phenylbutyrate and Genistein, to determine if they could be used to treat cystic fibrosis (CF). The most common genetic mutation found in patients with CF is called Delta F508. Due to this mutation, there is a lack of salt (chloride) movement in your nose, sinuses, lungs, intestines, pancreas and sweat glands. This lack of movement causes the clinical manifestations of the disease. Although Phenylbutyrate has been extensively used to treat patients with rare metabolic diseases, Phenylbutyrate is an investigational drug for the purpose of this study. Genistein is a naturally occurring substance that is found in food products such as soy and tofu, but is also an investigational drug for this study. When used together, both drugs may be able to restore normal chloride and salt (water) movements in body organs and glands in people with CF. We will be studying salt and water movement in the nose by a technique called nasal transepithelial potential difference (NPD).
New Combination	NCT00590538 ↗	Phenylbutyrate/Genistein Duotherapy in Delta F508-Heterozygotes (for Cystic Fibrosis)	Terminated	Children's Hospital of Philadelphia	Phase 1/Phase 2	2003-02-01	The purpose of this research study is to test a new combination of medicines, Phenylbutyrate and Genistein, to determine if they could be used to treat cystic fibrosis (CF). The most common genetic mutation found in patients with CF is called Delta F508. Due to this mutation, there is a lack of salt (chloride) movement in your nose, sinuses, lungs, intestines, pancreas and sweat glands. This lack of movement causes the clinical manifestations of the disease. Although Phenylbutyrate has been extensively used to treat patients with rare metabolic diseases, Phenylbutyrate is an investigational drug for the purpose of this study. Genistein is a naturally occurring substance that is found in food products such as soy and tofu, but is also an investigational drug for this study. When used together, both drugs may be able to restore normal chloride and salt (water) movements in body organs and glands in people with CF. We will be studying salt and water movement in the nose by a technique called nasal transepithelial potential difference (NPD).

All Clinical Trials for amiloride hydrochloride

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00004705 ↗	Study of Uridine Triphosphate (UTP) as an Aerosol Spray for Cystic Fibrosis	Completed	University of North Carolina	N/A	1996-09-01	OBJECTIVES: I. Determine the stability of uridine triphosphate (UTP) and examine the metabolism of exogenous nucleotides on airway epithelial surfaces in patients with cystic fibrosis. II. Determine the acute safety and efficacy of aerosolized UTP in children with cystic fibrosis.
NCT00004705 ↗	Study of Uridine Triphosphate (UTP) as an Aerosol Spray for Cystic Fibrosis	Completed	FDA Office of Orphan Products Development	N/A	1996-09-01	OBJECTIVES: I. Determine the stability of uridine triphosphate (UTP) and examine the metabolism of exogenous nucleotides on airway epithelial surfaces in patients with cystic fibrosis. II. Determine the acute safety and efficacy of aerosolized UTP in children with cystic fibrosis.
NCT00007592 ↗	Hypertension Screening and Treatment Program	Completed	US Department of Veterans Affairs		1989-06-01	Hypertension is one of the most common medical problems in the United States and in the VA health care system. It has been well-documented that hypertension can be effectively treated. However, there remain important unresolved clinical questions in the area of antihypertensive treatment. For example, how much is mortality affected by visit compliance, blood pressure control and type of antihypertensive agent? Or, are some regimens associated with more morbidity than others? Or, are there inexpensive regimens that are as effective as more expensive regimens? The amount of data that is available from this demonstration project (currently 6,100 patients) will help address these questions. The answers to these questions should result in better care for veterans with hypertension.
NCT00007592 ↗	Hypertension Screening and Treatment Program	Completed	VA Office of Research and Development		1989-06-01	Hypertension is one of the most common medical problems in the United States and in the VA health care system. It has been well-documented that hypertension can be effectively treated. However, there remain important unresolved clinical questions in the area of antihypertensive treatment. For example, how much is mortality affected by visit compliance, blood pressure control and type of antihypertensive agent? Or, are some regimens associated with more morbidity than others? Or, are there inexpensive regimens that are as effective as more expensive regimens? The amount of data that is available from this demonstration project (currently 6,100 patients) will help address these questions. The answers to these questions should result in better care for veterans with hypertension.
NCT00141596 ↗	Extracellular Fluid in Resistant Hypertension	Terminated	St George's, University of London	N/A	2003-07-01	The optimal treatment of drug resistant (defined as BP> 140/85 despite three anti-hypertensive drugs including a diuretic) is not well defined. This study aims to test the hypothesis that resistant hypertension is caused by excessive expansion of extracellular fluid volume. A secondary objective is to study which of three different antihypertensive drugs would be most useful in drug resistant hypertension.

Clinical Trial Conditions for amiloride hydrochloride

Condition Name

Condition Name for amiloride hydrochloride
Intervention	Trials
Hypertension	18
Cystic Fibrosis	7
Proteinuria	3
Bipolar Disorder	2

Condition MeSH

Condition MeSH for amiloride hydrochloride
Intervention	Trials
Hypertension	24
Fibrosis	7
Cystic Fibrosis	7
Kidney Diseases	4

Clinical Trial Locations for amiloride hydrochloride

Trials by Country

Trials by Country for amiloride hydrochloride
Location	Trials
United States	32
Brazil	14
India	8
France	8
Denmark	7

Trials by US State

Trials by US State for amiloride hydrochloride
Location	Trials
North Carolina	3
Pennsylvania	3
Alabama	2
Maryland	2
Utah	2

Clinical Trial Progress for amiloride hydrochloride

Clinical Trial Phase

Clinical Trial Phase for amiloride hydrochloride
Clinical Trial Phase	Trials
PHASE3	1
PHASE2	2
Phase 4	17

Clinical Trial Status

Clinical Trial Status for amiloride hydrochloride
Clinical Trial Phase	Trials
Completed	35
Recruiting	10
Unknown status	8

Clinical Trial Sponsors for amiloride hydrochloride

Sponsor Name

Sponsor Name for amiloride hydrochloride
Sponsor	Trials
Assistance Publique - Hôpitaux de Paris	6
Hospital de Clinicas de Porto Alegre	6
Cystic Fibrosis Foundation	3

Sponsor Type

Sponsor Type for amiloride hydrochloride
Sponsor	Trials
Other	129
Industry	8
U.S. Fed	4

Last updated: May 24, 2026

ILORIDE HYDROCHLORIDE clinical trials update, market analysis and projection

What is amiloride hydrochloride used for and what clinical programs are active?

Answer: Amiloride hydrochloride is an oral potassium-sparing diuretic used for hypertension and edema, and for mitigation of thiazide- or loop-related hypokalemia. The drug is also used off-label in selected electrolyte disorders. As of the current public clinical-trial landscape, activity is mostly in legacy indications, formulation changes, or pharmacokinetic studies rather than large Phase 3 registrational programs.

Primary marketed indications and typical positioning

• Hypertension (adjunct/combination use): Commonly paired with thiazide diuretics to reduce potassium loss.
• Edema: Used as part of diuretic regimens depending on underlying etiology.
• Hypokalemia risk reduction: Potassium-sparing effect is the main clinical rationale in combination therapy.

How to read “clinical trials update” for an older small molecule

For older generics, trial updates usually fall into:

• Bioequivalence (BE) / pharmacokinetic (PK) comparisons for generic entries and new product formats.
• Formulation optimization (e.g., IR vs modified-release designs).
• Safety and tolerability studies in specific populations.

Which clinical trials of amiloride hydrochloride are ongoing, recruiting, or recently completed?

Answer: No current, drug-wide, Phase 3 registrational program for amiloride hydrochloride is apparent in standard public registries; observed activity is limited to BE/PK or small, non-registrational studies.

Trial activity categories seen for older diuretics

• BE/PK comparisons for tablets and combination products.
• Studies evaluating food effects, dissolution, or steady-state electrolyte handling.
• Small investigator-led studies related to electrolyte physiology.

What is the global market for potassium-sparing diuretics and where does amiloride hydrochloride fit?

Answer: Amiloride hydrochloride sits in the smaller segment of potassium-sparing diuretics, alongside triamterene and related agents. The practical market demand is driven by:

• Use in fixed-dose combinations (especially with thiazides).
• Persistent clinician preference for potassium-sparing strategies in diuretic regimens.
• Generic competition and low unit value products.

Market dynamics shaping pricing

• Generics dominate: competitive tendering and pharmacy substitution reduce pricing power.
• Combination pull: demand is more stable when the molecule is embedded in combination products.
• Electrolyte monitoring: prescribing is influenced by safety profiles and guideline adherence rather than brand-specific differentiators.

Competitive landscape

• Direct pharmacologic class substitutes: triamterene (another potassium-sparing diuretic), spironolactone, and eplerenone depending on patient population and indication.
• Clinical practice substitutability: amiloride tends to be chosen when a potassium-sparing diuretic is specifically preferred or when combination regimens are used.

How does amiloride hydrochloride compare with triamterene and other potassium-sparing diuretics?

Answer: Amiloride and triamterene are both potassium-sparing diuretics but are commonly viewed as interchangeable class options in certain diuretic strategies. Spironolactone and eplerenone are often favored when aldosterone pathway modulation is clinically central, while amiloride is used more as a potassium-sparing adjunct.

Where substitution risk is highest

• Combination prescribing: When clinicians switch to a different fixed-dose diuretic combination, amiloride demand tracks accordingly.
• Electrolyte management: In hypokalemia prevention contexts, any potassium-sparing approach can substitute depending on tolerability and co-morbidities.

When does amiloride hydrochloride lose exclusivity, and what patent risk matters for new entrants?

Answer: For amiloride hydrochloride itself, exclusivity is not a major commercial gating factor because it is long marketed and widely generic. The main barriers for entrants are typically:

• Product-level IP (formulation, process, specific combination trademarks or fixed-dose approvals),
• Regulatory / manufacturing compliance, and
• Procedural timing for ANDA filings where relevant.

What patents protect amiloride hydrochloride and its formulations?

Answer: Protection for legacy small molecules is usually concentrated in:

• Formulation and manufacturing process patents tied to specific product lines,
• Combination-product patents (if any active),
• Use-related claims (method-of-use), which are less common for older, widely adopted indications unless newly asserted.

Practical implications for investors and litigators

• A new entrant facing an older molecule rarely confronts a broad “drug substance” wall.
• Patent attention should focus on Orange Book-listed product patents tied to specific NDA/ANDA reference products and the exact dosage form and strength.

What is the Orange Book status of amiloride hydrochloride products?

Answer: Orange Book status is product-specific. For amiloride hydrochloride, available listings typically reflect established, long-expired active ingredients with remaining product-level patents only where new formulations or combination products were approved more recently.

Why status must be checked at product level

Different reference products (NDA/ANDA bridges, combination SKUs, strengths) can have different:

• listed patents,
• expiration dates,
• pediatric exclusivity or regulatory exclusivities attached to specific approvals.

What generic entry risks exist for amiloride hydrochloride?

Answer: Generic entry risk is usually low for the active ingredient, but not zero for specific products. The main risks are:

• Product-level patent listings that can trigger Paragraph IV litigation for specific ANDA candidates.
• Citizen petitions or labeling disputes in rare cases for older products.
• Market share capture barriers caused by payer contracting, wholesaler preference, and inventory position.

Litigation as a gating factor

For older drugs, litigation tends to be episodic and tied to particular product patents rather than new “drug substance” claims.

What are the FDA regulatory pathways and what does that mean for amiloride hydrochloride market timing?

Answer: Market supply is primarily governed by ANDA economics and BE requirements. New entrants do not need full clinical efficacy packages if they pursue AB-rated generics through the ANDA pathway.

Regulatory levers that affect commercial ramp

• ANDA approval timelines and BE failures.
• Post-approval manufacturing scale-up and stability.
• Labeling and interchangeability decisions (state pharmacy formularies and pharmacy benefit manager protocols).

Market analysis: how much revenue is at stake and what could growth look like?

Answer: Because amiloride hydrochloride is a legacy, widely generic medication, growth is typically modest and tracks:

• Patient volume and prescribing stability for diuretic regimens,
• Combination product mix,
• Pricing pressure and volume shifts among generics.

Projection framework used for legacy diuretics

A workable projection for amiloride hydrochloride-based revenue typically uses:

• Unit demand: prescriptions and combination mix.
• Net price: payer dynamics and generic competition.
• Share movement: BE-driven generic entrants gain volume until contracted brands stabilize.

Likely trajectory

• Near term: stable volume, continued pricing compression.
• Medium term: growth mostly from population-level demand and combination mix, offset by substitution to other potassium-sparing or aldosterone antagonist options depending on clinical practice.

How many competitors are active and what is the competitive intensity?

Answer: Competitive intensity is high at the generic level. Most market access is won through:

• availability,
• price-to-formulary alignment,
• effective distribution,
• and BE performance for tablets and combination products.

What can change competitive intensity

• New formulation or combination approvals.
• Generic shortages (manufacturing or raw material issues).
• Periodic label or supply disruptions that briefly move market share.

Manufacturing and IP barriers: what could delay supply or increase cost?

Answer: Barriers tend to be operational rather than IP:

• Establishing validated manufacturing for solid oral dosage forms,
• Maintaining dissolution and stability specs,
• Preventing electrolyte-monitoring-related safety labeling issues and quality events.

Where process patents matter most

Process and formulation patents, when they exist for specific reference products, can block entry for those SKUs until expiration or settlement. For the active ingredient broadly, this is less common.

Key takeaways

• Amiloride hydrochloride is an older, widely generic potassium-sparing diuretic where major commercial gating factors are usually product-level rather than active-ingredient IP.
• Public clinical activity is generally limited to BE/PK or formulation work rather than new Phase 3 registrational programs.
• Market outlook is shaped by generics competition, combination prescribing mix, and ongoing pricing pressure, implying modest growth and stable-to-declining net price dynamics.

FAQs

1. Are there any new Phase 3 trials for amiloride hydrochloride?
2. Which fixed-dose combinations commonly include amiloride hydrochloride?
3. What are the main safety monitoring endpoints for amiloride in clinical use?
4. Can a new generic amiloride hydrochloride ANDA be blocked by product patents?
5. How does amiloride compare with spironolactone for potassium management in heart failure?

References

1. U.S. Food and Drug Administration. Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations.
2. ClinicalTrials.gov. Search results for “amiloride hydrochloride.”
3. FDA. Guidance for Industry: Bioequivalence Studies for Endpoint and Class of Drug Products.