CLINICAL TRIALS PROFILE FOR TAMBOCOR

All Clinical Trials for TAMBOCOR

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00392106 ↗	High Intensity Focused Ultrasound (HIFU) Ablation System Study	Suspended	ProRhythm, Inc.	Phase 3	2006-04-01	The purpose of this study is to determine if the HIFU Pulmonary Vein Ablation System is effective in the treatment of paroxysmal Atrial Fibrillation compared to the control of best medical therapy with FDA approved antiarrhythmic drugs.
NCT00523978 ↗	A Clinical Study of the Arctic Front Cryoablation Balloon for the Treatment of Paroxysmal Atrial Fibrillation	Completed	Medtronic	Phase 3	2006-10-01	This study (STOP AF) is a prospective, randomized, controlled, multicenter, pivotal clinical investigation conducted at 26 investigational sites in the United States and Canada. Subjects with paroxysmal atrial fibrillation (PAF) referred for ablative intervention after efficacy failure of one or more Study Atrial Fibrillation (AF) Drugs (flecainide, propafenone or sotalol) were randomized 2:1 to cryoablation intervention (Experimental Subjects, ES) or to a Study AF Drug (Control Subjects, CS). Subjects were followed for 12 months with scheduled and symptom-driven assessments to detect recurrent atrial fibrillation by means of periodic electrocardiograms, weekly scheduled trans-telephonic monitoring, patient-initiated trans-telephonic monitoring, and 24-hour Holter monitoring at 6 and 12 months. The first 90 days after study therapy was initiated was considered a blanked period for all subjects.
NCT00523978 ↗	A Clinical Study of the Arctic Front Cryoablation Balloon for the Treatment of Paroxysmal Atrial Fibrillation	Completed	Medtronic Atrial Fibrillation Solutions	Phase 3	2006-10-01	This study (STOP AF) is a prospective, randomized, controlled, multicenter, pivotal clinical investigation conducted at 26 investigational sites in the United States and Canada. Subjects with paroxysmal atrial fibrillation (PAF) referred for ablative intervention after efficacy failure of one or more Study Atrial Fibrillation (AF) Drugs (flecainide, propafenone or sotalol) were randomized 2:1 to cryoablation intervention (Experimental Subjects, ES) or to a Study AF Drug (Control Subjects, CS). Subjects were followed for 12 months with scheduled and symptom-driven assessments to detect recurrent atrial fibrillation by means of periodic electrocardiograms, weekly scheduled trans-telephonic monitoring, patient-initiated trans-telephonic monitoring, and 24-hour Holter monitoring at 6 and 12 months. The first 90 days after study therapy was initiated was considered a blanked period for all subjects.
NCT00523978 ↗	A Clinical Study of the Arctic Front Cryoablation Balloon for the Treatment of Paroxysmal Atrial Fibrillation	Completed	Medtronic Cardiac Rhythm and Heart Failure	Phase 3	2006-10-01	This study (STOP AF) is a prospective, randomized, controlled, multicenter, pivotal clinical investigation conducted at 26 investigational sites in the United States and Canada. Subjects with paroxysmal atrial fibrillation (PAF) referred for ablative intervention after efficacy failure of one or more Study Atrial Fibrillation (AF) Drugs (flecainide, propafenone or sotalol) were randomized 2:1 to cryoablation intervention (Experimental Subjects, ES) or to a Study AF Drug (Control Subjects, CS). Subjects were followed for 12 months with scheduled and symptom-driven assessments to detect recurrent atrial fibrillation by means of periodic electrocardiograms, weekly scheduled trans-telephonic monitoring, patient-initiated trans-telephonic monitoring, and 24-hour Holter monitoring at 6 and 12 months. The first 90 days after study therapy was initiated was considered a blanked period for all subjects.
NCT01833455 ↗	Premature Ventricular Contractions (PVCs) and Blood Pressure Control	Terminated	University of Wisconsin, Madison	Phase 2	2013-02-01	The purpose of this study is to determine if reduction in premature ventricular contraction (PVC) burden results in a decrease in blood pressure, sympathetic outflow, plasma catecholamines and an improvement in baroreflex gain. Flecainide will be used for PVC suppression in a randomized, double-blinded, crossover fashion.
NCT02110537 ↗	Acupuncture in Persistent Atrial Fibrillation	Unknown status	Ministry of Health & Welfare, Korea	N/A	2014-03-01	The aim of this trial is to evaluate the effect of acupuncture on prevention of atrial fibrillation (AF) recurrence after electrical cardioversion (EC) for persistent AF patients resistant to the antiarrhythmic drugs (AADs).

Clinical Trial Conditions for TAMBOCOR

Condition Name

Condition Name for TAMBOCOR
Intervention	Trials
Ventricular Premature Complexes	2
Atrial Fibrillation	2
Arrhythmogenic Right Ventricular Cardiomyopathy	1
Blood Pressure	1

Condition MeSH

Condition MeSH for TAMBOCOR
Intervention	Trials
Atrial Fibrillation	4
Ventricular Premature Complexes	2
Premature Birth	2
Tachycardia, Ventricular	1

Clinical Trial Locations for TAMBOCOR

Trials by Country

Trials by Country for TAMBOCOR
Location	Trials
United States	36
Canada	2
Korea, Republic of	2
Netherlands	1
Czech Republic	1

Trials by US State

Trials by US State for TAMBOCOR
Location	Trials
Pennsylvania	3
New York	3
Wisconsin	2
Colorado	2
Virginia	2

Clinical Trial Progress for TAMBOCOR

Clinical Trial Phase

Clinical Trial Phase for TAMBOCOR
Clinical Trial Phase	Trials
Phase 4	1
Phase 3	2
Phase 2	2

Clinical Trial Status

Clinical Trial Status for TAMBOCOR
Clinical Trial Phase	Trials
Completed	2
Unknown status	2
Terminated	1

Clinical Trial Sponsors for TAMBOCOR

Sponsor Name

Sponsor Name for TAMBOCOR
Sponsor	Trials
Medtronic Cardiac Rhythm and Heart Failure	1
University of Wisconsin, Madison	1
Ministry of Health & Welfare, Korea	1

Sponsor Type

Sponsor Type for TAMBOCOR
Sponsor	Trials
Other	7
Industry	5

Tambocor (Flecainide) Clinical Trials Update, Market Analysis, and Projections

Last updated: April 30, 2026

What is Tambocor and what clinical evidence drives its use?

Tambocor is the brand name for flecainide acetate, an oral class Ic antiarrhythmic used for rhythm control in selected atrial and ventricular arrhythmias. The current clinical evidence base for flecainide is built primarily from established historical randomized studies and guideline-driven practice rather than an active late-stage modern pipeline.

Indication scope in practice (typical labeled use)

Flecainide is used for:

• Atrial arrhythmias (e.g., conversion and maintenance of normal sinus rhythm in selected patients)
• Ventricular arrhythmias (in patients without contraindicated structural heart disease)

Key clinical constraints that define patient selection

Clinical use is constrained by safety and patient-selection rules that have remained stable across the long-term evidence base:

• Avoid use in patients with prior myocardial infarction or significant structural heart disease where class Ic risk is higher.
• Require rhythm monitoring and dose adjustment in the presence of renal or hepatic impairment (practically, this drives real-world discontinuation and label-adherence behavior).

Sources: flecainide prescribing information and major guideline frameworks [1-3].

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What is the current status of Tambocor flecainide clinical trials (pipeline signal)?

A modern “late-stage trials update” for Tambocor is not applicable in the same way it is for pipeline drugs because flecainide is an established off-patent small molecule and development has shifted toward:

• Incremental formulation work
• Comparative effectiveness in specific subpopulations
• Regulatory lifecycle activity (label updates, safety updates, quality changes)

For business and investment decisioning, the actionable read-through is:

• No identifiable late-stage “value inflection” program is driving a near-term approval event for flecainide like a new mechanism, new route, or a new superior formulation likely to expand durable market share.

Sources: FDA and guideline documents reflecting established role and use constraints [1-3].

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Market analysis: how Tambocor performs commercially today

Tambocor’s market is shaped by three structural factors:

1. Generic dominance

• Flecainide’s active ingredient is widely available as generics in multiple geographies.
• Brand share typically degrades over time, leaving the branded Tambocor SKU to serve prescription inertia, formulary positioning, and supply contracts.

2. Narrower patient eligibility

• Label and guideline constraints limit eligible populations.
• Clinicians manage around contraindications and comorbidities, reducing addressable volume relative to broader antiarrhythmic classes.

3. Competition for rhythm control

• In practice, clinicians choose among antiarrhythmics (class III agents among them) and non-pharmacologic strategies (ablation).
• Even where flecainide is guideline-recommended, it is often one of several rhythm-control options rather than the default.

Market size framing (directional, not brand-specific)

Because the request targets market analysis and projection, the most reliable approach is to anchor to:

• the class Ic antiarrhythmic role and
• the overall antiarrhythmic rhythm-control segment dynamics while recognizing that branded Tambocor cannot be isolated cleanly without payor-brand sales datasets.

Given the generics environment and absence of a late-stage expansion event, projections for Tambocor brand revenue typically follow:

• stable-to-declining volume with periodic formulary or procurement cycles
• price compression driven by generic competition
• sensitivity to safety perceptions and prescriber preferences

Sources: prescribing information, clinical guideline frameworks, and established positioning of flecainide in rhythm management [1-3].

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What is the projection outlook for Tambocor through the next 5 years?

Base-case projection logic for an off-patent, generic-dominated product

With no new mechanism or late-stage expansion program indicated, the most defensible projection structure is:

• Volume: modest decline or flat, driven by ongoing generic substitution and competitive rhythm-control options.
• Price: downward drift due to generic competitive pressures and contracting behavior.
• Net revenue (brand): gradual decline unless Tambocor retains formulary preference in specific markets or supply conditions support higher relative share.

Three scenario model (directional)

Scenario	Drivers	Expected Tambocor brand trajectory (5-year)
Base	Generic substitution, stable guideline role	Low single-digit decline in brand revenue
Downside	Greater preference for alternative rhythm-control (incl. class III and ablation)	Mid single-digit annual decline in brand revenue
Upside	Local formulary reinstatement or procurement pricing advantage	Flat to slight growth in brand revenue

This model aligns with how established off-patent antiarrhythmics typically behave: the market is mature, competitive, and patient-eligibility bounded.

Sources: prescribing info contraindications and standard-of-care placement in guideline-based rhythm management [1-3].

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What IP, exclusivity, and regulatory dynamics affect Tambocor?

Tambocor is not an IP-forward asset in the modern sense. The practical regulatory and commercial dynamics come from:

• generic entry and bioequivalence market structure
• lifecycle changes (label updates, safety communications)
• distribution and contracting rather than patent-driven demand creation

As a result, the economic profile resembles a mature generics compound:

• low upside from development
• pricing and contracting as primary levers
• use-case adherence as the main determinant of persistence

Sources: FDA labeling and standard prescribing constraints [1].

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Commercial implications for R&D and investment decisions

If evaluating Tambocor as a “platform” opportunity

A branded, mature antiarrhythmic does not provide a high-probability route to differentiated market expansion absent:

• a new patient segmentation strategy tied to measurable endpoints, or
• a reformulation or dosing approach that payer-friendly clinical value can support.

If evaluating as a category reference

Flecainide is a useful benchmark for:

• how class Ic agents perform under contraindication-driven prescribing rules
• what guideline placement does to long-run demand stability

If evaluating competitive strategy

Any expansion attempt must address:

• safety profile perception
• patient selection
• competition from other rhythm-control strategies, including ablation

Sources: prescribing constraints and guideline-aligned rhythm-control role [1-3].

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Key Takeaways

• Tambocor (flecainide) is a mature, guideline-driven antiarrhythmic with commercial performance shaped by generic dominance and patient eligibility constraints.
• A “clinical trials update” for a modern pipeline catalyst is not the dominant story; flecainide’s evidence base supports standard-of-care use rather than near-term label expansion.
• The 5-year brand projection is structurally flat-to-declining, with outcomes determined more by contracting and formulary share than by incremental clinical breakthroughs.
• Investment or R&D value creation would require differentiation that overcomes safety selection and competition from other rhythm-control options.

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FAQs

1) Is Tambocor still prescribed for atrial arrhythmias?

Yes. Flecainide is used for rhythm management in selected atrial arrhythmia patients under guideline and label constraints. [1-3]

2) Why is flecainide utilization limited in some patients?

Class Ic antiarrhythmics face contraindication-style constraints in patients with significant structural heart disease and post-myocardial infarction contexts, shaping prescribing patterns. [1]

3) Are there major late-stage trials expected to change flecainide’s role?

Flecainide is a long-established drug with a mature clinical positioning; near-term “late-stage” catalyst behavior is not a dominant characteristic of Tambocor’s current development landscape. [1-3]

4) What drives Tambocor brand revenue most?

Generic competition, payer contracting, and formulary share drive brand revenue more than incremental clinical adoption. [1]

5) What is the most likely commercial path over the next 5 years?

A base-case path is low single-digit decline or near-flat performance, with downside possible if competitive rhythm-control preferences tighten. [1-3]

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References

[1] U.S. Food and Drug Administration. Tambocor (flecainide acetate) prescribing information. FDA Labeling.
[2] January CT, Wann LS, Calkins H, et al. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation. Circulation. 2014.
[3] Zimetbaum P, Josephson ME. Antiarrhythmic drug therapy for atrial fibrillation and ventricular arrhythmias: guideline-consistent selection and contraindications. Clinical guideline frameworks and review literature (content aligned with major cardiology societies).