CLINICAL TRIALS PROFILE FOR INSPRA

All Clinical Trials for Inspra

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00108251 ↗	Aldosterone Antagonism in Diastolic Heart Failure	Completed	US Department of Veterans Affairs	Phase 4	2004-08-01	The primary purpose of this study is to determine whether eplerenone has a beneficial effect on improving exercise ability in patients with diastolic heart failure.
NCT00108251 ↗	Aldosterone Antagonism in Diastolic Heart Failure	Completed	VA Office of Research and Development	Phase 4	2004-08-01	The primary purpose of this study is to determine whether eplerenone has a beneficial effect on improving exercise ability in patients with diastolic heart failure.
NCT00223717 ↗	Treatment of Supine Hypertension in Autonomic Failure	Completed	Vanderbilt University	Phase 1	2001-01-01	Supine hypertension is a common problem that affects at least 50% of patients with primary autonomic failure. Supine hypertension can be severe, and complicates the treatment of orthostatic hypotension. Drugs used for the treatment of orthostatic hypotension (eg, fludrocortisone and pressor agents), worsen supine hypertension. High blood pressure may also cause target organ damage in this group of patients. The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure have not been defined. In a study, we, the investigators at Vanderbilt University, examined 64 patients with AF, 29 with pure autonomic failure (PAF) and 35 with multiple system atrophy (MSA). 66% of patients had supine systolic (systolic blood pressure [SBP] > 150 mmHg) or diastolic (diastolic blood pressure [DBP] > 90 mmHg) hypertension (average blood pressure [BP]: 179 ± 5/89 ± 3 mmHg in 21 PAF and 175 ± 5/92 ± 3 mmHg in 21 MSA patients). Plasma norepinephrine (92 ± 15 pg/mL) and plasma renin activity (0.3 ± 0.05 ng/mL per hour) were very low in a subset of patients with AF and supine hypertension. (Shannon et al., 1997). Our group has showed that a residual sympathetic function contributes to supine hypertension in patients with severe autonomic failure and that this effect is more prominent in patients with MSA than in those with PAF (Shannon et al., 2000). MSA patients had a marked depressor response to low infusion rates of trimethaphan, a ganglionic blocker; the response in PAF patients was more variable. At 1 mg/min, trimethaphan decreased supine SBP by 67 +/- 8 and 12 +/- 6 mmHg in MSA and PAF patients, respectively (P < 0.0001). MSA patients with supine hypertension also had greater SBP response to oral yohimbine, a central alpha2 receptor blocker, than PAF patients. Plasma norepinephrine decreased in both groups, but heart rate did not change in either group. This result suggests that residual sympathetic activity drives supine hypertension in MSA; in contrast, supine hypertension in PAF. It is hoped that from this study will emerge a complete picture of the supine hypertension of autonomic failure. Understanding the mechanism of this paradoxical hypertension in the setting of profound loss of sympathetic function will improve our approach to the treatment of hypertension in autonomic failure, and it could also contribute to our understanding of hypertension in general.
NCT00223717 ↗	Treatment of Supine Hypertension in Autonomic Failure	Completed	Vanderbilt University Medical Center	Phase 1	2001-01-01	Supine hypertension is a common problem that affects at least 50% of patients with primary autonomic failure. Supine hypertension can be severe, and complicates the treatment of orthostatic hypotension. Drugs used for the treatment of orthostatic hypotension (eg, fludrocortisone and pressor agents), worsen supine hypertension. High blood pressure may also cause target organ damage in this group of patients. The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure have not been defined. In a study, we, the investigators at Vanderbilt University, examined 64 patients with AF, 29 with pure autonomic failure (PAF) and 35 with multiple system atrophy (MSA). 66% of patients had supine systolic (systolic blood pressure [SBP] > 150 mmHg) or diastolic (diastolic blood pressure [DBP] > 90 mmHg) hypertension (average blood pressure [BP]: 179 ± 5/89 ± 3 mmHg in 21 PAF and 175 ± 5/92 ± 3 mmHg in 21 MSA patients). Plasma norepinephrine (92 ± 15 pg/mL) and plasma renin activity (0.3 ± 0.05 ng/mL per hour) were very low in a subset of patients with AF and supine hypertension. (Shannon et al., 1997). Our group has showed that a residual sympathetic function contributes to supine hypertension in patients with severe autonomic failure and that this effect is more prominent in patients with MSA than in those with PAF (Shannon et al., 2000). MSA patients had a marked depressor response to low infusion rates of trimethaphan, a ganglionic blocker; the response in PAF patients was more variable. At 1 mg/min, trimethaphan decreased supine SBP by 67 +/- 8 and 12 +/- 6 mmHg in MSA and PAF patients, respectively (P < 0.0001). MSA patients with supine hypertension also had greater SBP response to oral yohimbine, a central alpha2 receptor blocker, than PAF patients. Plasma norepinephrine decreased in both groups, but heart rate did not change in either group. This result suggests that residual sympathetic activity drives supine hypertension in MSA; in contrast, supine hypertension in PAF. It is hoped that from this study will emerge a complete picture of the supine hypertension of autonomic failure. Understanding the mechanism of this paradoxical hypertension in the setting of profound loss of sympathetic function will improve our approach to the treatment of hypertension in autonomic failure, and it could also contribute to our understanding of hypertension in general.
NCT00293150 ↗	Reversing Endothelial and Diastolic Dysfunction and Improving Collagen Turnover in Diastolic Heart Failure	Terminated	The Cleveland Clinic	Phase 4	2003-09-01	The principle aim is to determine the efficacy of eplerenone in patients with diastolic heart failure to reverse cardiac remodeling and to improve diastolic function.
NCT00505336 ↗	The Effect of Eplerenone and Atorvastatin on Markers of Collagen Turnover in Diastolic Heart Failure	Completed	St Vincent's University Hospital, Ireland	N/A	2006-04-01	To investigate whether the medicines eplerenone or atorvastatin have a favourable effect on diastolic heart failure. Eplerenone is a drug that has been shown to be beneficial in Chronic Heart Failure due to pump failure. It can increase life expectancy and improve symptoms in these patients. It is not known whether or not eplerenone might be beneficial in heart failure with normal pump function (diastolic heart failure). Atorvastatin is one of a group of cholesterol lowering medicines called statins, which have been shown to reduce cardiovascular disease in patients irrespective of whether cholesterol levels are high or normal. It is not known whether atorvastatin also reduces fibrosis of the heart which is one of the causes of diastolic heart failure. Study hypothesis 1. To investigate the impact of aldosterone antagonism or statin therapy on markers of collagen turnover in patients with diastolic heart failure. 2. To assess the impact of aldosterone antagonism or statin therapy on markers of diastolic dysfunction and indices of clinical well being in patients with diastolic heart failure.

Clinical Trial Conditions for Inspra

Condition Name

Condition Name for Inspra
Intervention	Trials
Hypertension	9
Metabolic Syndrome	3
Diastolic Heart Failure	2
Metabolic Syndrome X	2

Condition MeSH

Condition MeSH for Inspra
Intervention	Trials
Hypertension	7
Metabolic Syndrome	5
Heart Failure	4
Metabolic Syndrome X	3

Clinical Trial Locations for Inspra

Trials by Country

Trials by Country for Inspra
Location	Trials
United States	24
Canada	7
Netherlands	6
United Kingdom	4
France	4

Trials by US State

Trials by US State for Inspra
Location	Trials
Tennessee	5
Ohio	3
Massachusetts	2
Pennsylvania	2
Missouri	2

Clinical Trial Progress for Inspra

Clinical Trial Phase

Clinical Trial Phase for Inspra
Clinical Trial Phase	Trials
Phase 4	13
Phase 3	5
Phase 2/Phase 3	1

Clinical Trial Status

Clinical Trial Status for Inspra
Clinical Trial Phase	Trials
Completed	19
Terminated	6
Unknown status	3

Clinical Trial Sponsors for Inspra

Sponsor Name

Sponsor Name for Inspra
Sponsor	Trials
Vanderbilt University Medical Center	5
Pfizer	4
Vanderbilt University	3

Sponsor Type

Sponsor Type for Inspra
Sponsor	Trials
Other	48
Industry	10
U.S. Fed	3

Last updated: May 2, 2026

INSPRA (eplerenone) Clinical Trials Update, Market Analysis, and Projection

What is INSPRA and where does it sit in the portfolio?

INSPRA is eplerenone, an oral, selective mineralocorticoid receptor antagonist (MRA). The core marketed indications remain centered on:

• Heart failure (post–myocardial infarction with left ventricular dysfunction): reduces risk of mortality and morbidity in eligible patients (label-based positioning).
• Heart failure (NYHA class II with reduced ejection fraction): risk reduction in chronic heart failure populations (label-based positioning).

Eplerenone competes in chronic heart failure and post-MI cardioprotection against other MRAs, most notably spironolactone and newer MRAs in the wider cardiovascular pipeline landscape.

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What does the clinical trials landscape for eplerenone look like right now?

A “clinical trials update” for INSPRA is constrained by the fact that eplerenone is an older, established product and many studies are label expansions, investigator-initiated trials, or post-approval comparisons rather than broad new pivotal programs. Within that reality, the most decision-relevant signals are:

1. Ongoing interventional trials (if any) are typically incremental and often tied to subgroup outcomes

• Common motifs: comparative efficacy/tolerability versus other MRAs, biomarker-driven or genotype-influenced response assessments, and renal safety or electrolyte monitoring strategies in real-world or enriched populations.

2. Regulatory activity tends to cluster around safety updates and label refinements rather than major new indications

• For established MRAs, the high-probability path is safety labeling, renal monitoring language, and integration into guideline-aligned treatment algorithms.

3. Trial activity is often eclipsed by newer guideline-preferred agents

• In heart failure, the market impact comes from therapeutic class switching (SGLT2 inhibitors, ARNI, beta-blocker intensity, etc.). For MRAs, eplerenone remains relevant, but the incremental adoption depends on tolerability and guideline positioning relative to competing MRAs.

Bottom line: without a specific trial registry snapshot in the prompt, a complete, up-to-date “trial-by-trial” update cannot be produced accurately.

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Where does INSPRA generate revenue and how does the competitive set shape demand?

Core demand drivers

• Guideline adherence for post-MI left ventricular dysfunction and chronic heart failure where MRAs remain a recommended class.
• Switching behavior within the MRA segment based on tolerability, endocrine side effects, and prescriber preference.
• Kidney function and potassium monitoring protocols that influence persistence and adherence.

Competitive set

• Spironolactone (generic and long-standing) is the main competitive head-to-head in MRAs. Price and formulary access often favor generic spironolactone unless prescriber preference and tolerability tilt toward eplerenone.
• Newer cardiovascular agents influence the share of regimen intensity. Even when MRAs remain recommended, overall regimen changes can slow incremental growth for any single class member.

Market access reality

• Eplerenone faces ongoing pressure from:
  • Formulary tiering and generic spillover from spironolactone.
  • Prior authorization in some systems that require documentation of intolerance or endocrine side-effect risk.
  • Real-world kidney monitoring burden, which can reduce utilization in settings with limited lab access.

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How is eplerenone positioned versus spironolactone and what does that imply for adoption?

Relative attributes that influence switching inside MRAs

• Eplerenone is generally chosen when clinicians want to minimize sex-hormone-related adverse effects associated with spironolactone.
• Both drugs share the risk of hyperkalemia and require careful renal and potassium monitoring.

Adoption implications

• Adoption trends for eplerenone are typically strongest where:
  • Endocrine side effects from spironolactone are a known barrier.
  • Health systems implement close lab monitoring and have established MRA protocols.
  • Prescribers prefer eplerenone for long-term tolerability.

Competitive implication: unless there is a meaningful differentiator through trial-confirmed superiority in a specific subgroup or new guideline inclusion that favors eplerenone over alternatives, the market typically grows slowly and remains sensitive to generic pricing in the broader MRA class.

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What are the market projections for INSPRA through the next 5 years?

A credible projection requires baseline revenue, regional penetration, payer behavior, and a validated forecasting model tied to actual utilization and pricing. The prompt does not provide the underlying sales base, geography, or forecast methodology inputs, so a complete and accurate numeric projection cannot be constructed.

Non-numeric, decision-relevant directional view (qualitative):

• Expect mature-market dynamics: modest growth or flat-to-slight decline depending on generic mix shifts and formulary changes.
• Upside scenarios require evidence that either:
  • Guideline updates increase MRA use intensity in populations where eplerenone is preferred.
  • Safety/tolerability data supports switching at scale from spironolactone.
• Downside scenarios follow:
  • Tighter payer controls, greater spironolactone substitution, or reduced MRA persistence due to monitoring burdens.

Bottom line: market projection in numeric terms cannot be produced accurately from the information available in the prompt.

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Clinical and regulatory outlook: what matters for INSPRA’s next phase?

Will INSPRA likely face generic erosion or brand pressure?

Eplerenone’s brand economics are governed by generic availability, which tends to suppress branded premium pricing. Any brand-relevant outlook depends on:

• Differential formulary placement between brand and generic products.
• Competition that increases substitution rates.
• Stability of MRA guideline inclusion and dosing persistence.

What would change the uptake curve in practice?

Uptake accelerators that are typically required for an established drug include:

• A clear subgroup advantage that changes prescribing behavior.
• A new label that expands eligible patient populations.
• Strong safety evidence that reduces the monitoring burden or improves persistence.

Without those programmatic changes, mature-market behavior dominates.

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Key Takeaways

• INSPRA (eplerenone) remains an established MRA anchored in guideline-aligned cardiovascular indications.
• Competitive pressure is structurally high from spironolactone (generic pricing) and from broader heart failure regimen shifts that reduce incremental share for any one drug.
• A complete, up-to-date clinical trials update and a numeric 5-year market projection cannot be produced accurately from the prompt because no registries, sales baselines, geography, or forecasting inputs are provided.
• The practical driver of future performance is whether eplerenone maintains or expands its share inside MRAs through formulary access and tolerability-based switching.

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FAQs

1) Is INSPRA still actively used in heart failure?

Yes. Eplerenone remains used where MRAs are indicated, particularly in patients where prescribers prefer eplerenone’s tolerability profile versus spironolactone and where monitoring protocols support safe use.

2) What is INSPRA’s main competitive threat?

Spironolactone within the MRA class, mainly via formulary substitution and generic pricing dynamics.

3) What is the key clinical risk for eplerenone?

Hyperkalemia and the need for renal and potassium monitoring to maintain safety.

4) What would most likely expand INSPRA demand?

A new or expanded label that increases eligible patient populations, or robust subgroup evidence that changes prescribing patterns toward eplerenone at scale.

5) Can we forecast INSPRA’s revenue without baseline sales and geography?

No. Numeric projections require baseline revenue, regional mix, pricing assumptions, and market access and uptake parameters.

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References

[1] U.S. Food and Drug Administration. INSPRA (eplerenone) Prescribing Information. FDA access.