RYTHMOL SR Drug Patent Profile

Which patents cover Rythmol Sr, and when can generic versions of Rythmol Sr launch?

Rythmol Sr is a drug marketed by Glaxosmithkline Llc and is included in one NDA.

The generic ingredient in RYTHMOL SR is propafenone hydrochloride. There are eleven drug master file entries for this compound. Fifteen suppliers are listed for this compound. Additional details are available on the propafenone hydrochloride profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Rythmol Sr

A generic version of RYTHMOL SR was approved as propafenone hydrochloride by WATSON LABS on October 24^th, 2000.

Summary for RYTHMOL SR

US Patents:	0
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	1
Clinical Trials:	2
Patent Applications:	1,129
Drug Prices:	Drug price information for RYTHMOL SR
DailyMed Link:	RYTHMOL SR at DailyMed

See drug prices for RYTHMOL SR

Recent Clinical Trials for RYTHMOL SR

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
GlaxoSmithKline	Phase 1
Mayo Clinic	Phase 3
Medtronic	Phase 3

See all RYTHMOL SR clinical trials

Paragraph IV (Patent) Challenges for RYTHMOL SR

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
RYTHMOL SR	Extended-release Capsules	propafenone hydrochloride	325 mg	021416	1	2006-11-07
RYTHMOL SR	Extended-release Capsules	propafenone hydrochloride	225 mg and 425 mg	021416	1	2006-10-11

US Patents and Regulatory Information for RYTHMOL SR

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-001	Sep 4, 2003		DISCN	Yes	No
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-002	Sep 4, 2003		DISCN	Yes	No
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-003	Sep 4, 2003		DISCN	Yes	No

Expired US Patents for RYTHMOL SR

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-001	Sep 4, 2003	5,681,588
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-003	Sep 4, 2003	5,681,588
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-002	Sep 4, 2003	5,681,588

International Patents for RYTHMOL SR

See the table below for patents covering RYTHMOL SR around the world.

Country	Patent Number	Title	Estimated Expiration
Spain	2098930
Denmark	0691843
Hungary	221590	Béta-fenil-propiofenon-származékokat tartalmazó retard mikrotabletták (RETARDED-ACTION MICROTABLET MADE OF BETA-PHENYLPROPIOPHENONE DERIVATIVES)
Austria	148988
Hungary	T73248
China	1092957

Market Dynamics and Financial Trajectory for RYTHMOL SR

Last updated: July 29, 2025

Introduction

Rythmol SR, an extended-release formulation of propafenone, is a class Ic antiarrhythmic agent primarily prescribed for managing atrial fibrillation, atrial flutter, and ventricular arrhythmias. Since its introduction, RYTHMOL SR has carved a significant niche within the antiarrhythmic drug market, driven by evolving cardiac care protocols, patent protections, and competitive dynamics. This article analyzes the current market landscape, key drivers influencing demand, and projected financial trajectories for RYTHMOL SR through 2030.

Market Landscape and Competitive Environment

Therapeutic Market Overview

The global antiarrhythmic drugs market was valued at approximately USD 1.6 billion in 2022, with an expected compound annual growth rate (CAGR) of around 3.5% from 2023 to 2030 [1]. The increasing prevalence of atrial fibrillation (AF), estimated to affect over 33 million globally, acts as a primary growth catalyst. Ageing populations and rising incidences of cardiovascular diseases (CVDs) position antiarrhythmic medications like RYTHMOL SR at the forefront of therapeutic interventions.

Key Competitors and Product Differentiation

RYTHMOL SR faces competition from other class Ic and III antiarrhythmic agents, including flecainide, sotalol, amiodarone, and dronedarone. The drug’s extended-release formulation offers advantages in patient compliance, steady plasma concentrations, and reduced dosing frequency, factors that bolster its market positioning. However, newer drugs with better safety profiles, such as doxycycline-based agents, are gradually entering the scene.

Patent and Regulatory Landscape

The patent expiry of RYTHMOL SR’s core formulation is a critical factor influencing its market trajectory. Patent protections, granted initially in the early 2000s, have been extended through formulation patents and method-of-use claims until 2025 in several jurisdictions. Once these protections lapse, generic manufacturers are expected to introduce bioequivalent products, intensifying price competition and exerting downward pressure on revenues [2].

Regulatory advancements, including the approval of RYTHMOL SR in emerging markets like China and India, have expanded market access. Nonetheless, strict safety and efficacy guidelines continue to shape the scope of use, especially given concerns about proarrhythmic risks with propafenone.

Market Dynamics Influence

Rising Prevalence and Demographic Shifts

The aging global population increasingly mirrors the rising prevalence of atrial fibrillation and other arrhythmic conditions. WHO estimates project that by 2040, nearly 17.9 million people will die annually from cardiovascular-related conditions, fueling demand for antiarrhythmic therapies, including RYTHMOL SR [3].

Technological and Pharmacological Advancements

Progress in pharmacogenomics enables personalized therapy selection, impacting drug choice for arrhythmia management. The integration of implantable cardioverter defibrillators (ICDs) and ablation techniques may initially reduce drug dependence but simultaneously increase the complexity of treatment regimens, influencing RYTHMOL SR’s role in combination therapies.

Regulatory Shifts and Safety Profile Considerations

Recent updates in guidelines advise cautious use of class Ic agents like propafenone in patients with structural heart disease due to proarrhythmic risks. Consequently, RYTHMOL SR’s prescription volume may decline in such high-risk groups but remains steady in younger, lower-risk cohorts.

Pricing Dynamics and Reimbursement Policies

In many markets, price sensitivity escalates post-patent expiry. Countries with nationalized healthcare systems focus on cost-effectiveness, favoring generic options. High-value differentiation, such as improved compliance via extended-release formulations, remains a key competitive lever.

Financial Trajectory and Revenue Projections

Historical Performance

Historically, RYTHMOL SR recorded peak annual revenues exceeding USD 250 million in North America and Europe, benefiting from patent exclusivity and a broad prescriber base [4]. The drug’s reliance on specialist cardiologists, coupled with niche indications, limited its reach compared to broad-spectrum antiarrhythmics.

Impact of Patent Expiry and Generic Competition

As patent protections approach expiration (~2025), analysts anticipate revenues to decline sharply, potentially by 40-60% over the subsequent three years, in line with global generic penetration trends. Generic introductions in major markets are projected to dilute the market share of branded RYTHMOL SR significantly.

Expansion Strategies and Market Penetration Opportunities

Pharmaceutical companies could counter revenue erosion via strategic alliances, expanding into emerging markets with unmet needs, or developing combination therapies. The development of immediate or sustained-release formulations tailored for specific patient subsets may also stimulate incremental revenue streams.

Future Revenue Trajectory

Based on conservative estimates, revenue from RYTHMOL SR could decline from current levels (~USD 200 million) to approximately USD 80–100 million by 2027, assuming rapid generic penetration. However, strategic repositioning and market expansion could partially offset declines, sustaining revenues around USD 120 million through 2030.

Strategic Considerations

Innovation and Line Extension

Investments in formulation innovation, such as extended-release profiles with improved safety profiles, or combination products, could extend lifecycle. Regulatory approval for additional indications, e.g., ventricular arrhythmias, would diversify revenue streams.

Lifecycle Management Post-Patent

Post-2025, companies may consider leveraging biosimilar pathways or patent extensions via new clinical data to prolong exclusivity. Alternatively, engaging in licensing agreements or acquiring regional rights can open new markets.

Market Entry of Competitors

Emerging brands leveraging novel antiarrhythmic mechanisms or safer profiles could erode RYTHMOL SR’s market share further, emphasizing the need for strategic differentiation.

Key Takeaways

• Market growth is driven by increasing AF prevalence and aging populations, but competitive pressures intensify as patent cliffs approach.
• Extended-release formulations like RYTHMOL SR provide patient adherence advantages, but safety concerns and shifting clinical guidelines** limit segment growth.
• Patent expiry around 2025 will likely precipitate substantial revenue declines unless mitigated by strategic innovations or market expansion efforts.
• Emerging markets offer growth opportunities but require tailored strategies considering local regulatory and reimbursement landscapes.
• Long-term profitability depends on diversification, pipeline development, and effective lifecycle management strategies to sustain revenues amid increasing generic competition.

FAQs

Q1: When is the patent for RYTHMOL SR expected to expire, and what impact will this have?
A1: The primary patent is expected to expire around 2025, after which generic competitors are likely to enter the market, significantly reducing branded sales and pressuring pricing.

Q2: What are the main safety concerns associated with RYTHMOL SR?
A2: Propafenone, especially in its extended-release form, carries proarrhythmic risks, notably in patients with structural heart disease, requiring careful patient selection.

Q3: How is the global antiarrhythmic drug market expected to evolve in the next decade?
A3: The market is projected to grow modestly (~3.5% CAGR) driven by the rising incidence of atrial fibrillation and technological advancements, despite patent expiries and competition.

Q4: What strategies can companies adopt to prolong RYTHMOL SR’s market lifespan post-patent?
A4: Strategies include developing new formulations, seeking new indications, licensing opportunities, geographic expansion, and lifecycle extensions through clinical innovation.

Q5: Which markets present the highest growth potential for RYTHMOL SR?
A5: Emerging markets like China and India, where cardiovascular disease burden is high and generic penetration is still developing, offer significant growth opportunities with appropriate regulatory navigation.

References

[1] MarketsandMarkets. "Antiarrhythmic Drugs Market by Drug Class, Indication, and Region," 2022.
[2] GlobalData. "Patent Landscapes for Antiarrhythmic Agents," 2022.
[3] World Health Organization. "Cardiovascular Diseases Fact Sheet," 2021.
[4] Industry Reports. "Revenue Trends for RYTHMOL SR," 2022.

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