RYTHMOL Drug Patent Profile

Which patents cover Rythmol, and what generic alternatives are available?

Rythmol is a drug marketed by Glaxosmithkline Llc and is included in two NDAs.

The generic ingredient in RYTHMOL 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

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

Summary for RYTHMOL

US Patents:	0
Applicants:	1
NDAs:	2
Raw Ingredient (Bulk) Api Vendors:	181
Clinical Trials:	2
Drug Prices:	Drug price information for RYTHMOL
What excipients (inactive ingredients) are in RYTHMOL?	RYTHMOL excipients list
DailyMed Link:	RYTHMOL at DailyMed

See drug prices for RYTHMOL

Recent Clinical Trials for RYTHMOL

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

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

See all RYTHMOL clinical trials

US Patents and Regulatory Information for RYTHMOL

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	propafenone hydrochloride	TABLET;ORAL	019151-001	Nov 27, 1989		DISCN	Yes	No
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-001	Sep 4, 2003		DISCN	Yes	No
Glaxosmithkline Llc	RYTHMOL	propafenone hydrochloride	TABLET;ORAL	019151-003	Nov 20, 1992		DISCN	Yes	No
Glaxosmithkline Llc	RYTHMOL	propafenone hydrochloride	TABLET;ORAL	019151-002	Nov 27, 1989		DISCN	Yes	No
Glaxosmithkline Llc	RYTHMOL SR	propafenone hydrochloride	CAPSULE, EXTENDED RELEASE;ORAL	021416-003	Sep 4, 2003		DISCN	Yes	No

Market Dynamics and Financial Trajectory for RYTHMOL

Last updated: April 10, 2026

What is RYTHMOL and its Approval Status?

RYTHMOL (mexiletine hydrochloride) is an antiarrhythmic agent used primarily to treat ventricular arrhythmias. It was developed by Boehringer Ingelheim and approved by the U.S. Food and Drug Administration (FDA) in 1980. Its primary indication covers the suppression of premature ventricular contractions in certain cardiac conditions.

Market Size and Key Drivers

The global antiarrhythmic drug market valued approximately $2.5 billion in 2022, projected to grow at a compound annual growth rate (CAGR) of 4.2% through 2030 [1]. RYTHMOL's market share is constrained by competition from newer agents: amiodarone, sotalol, and catheter ablation approaches.

• Market Penetration: RYTHMOL's sales peaked in the mid-1990s but declined due to safety concerns and preference shifts.
• Market Drivers:
  • Increased prevalence of arrhythmias, partly driven by aging populations.
  • Rising awareness and diagnosis of ventricular arrhythmias.
  • Continued use in specific, refractory cases where newer agents are contraindicated.

Patent and Regulatory Landscape

RYTHMOL's patent expired in the late 1990s. No recent patent protections hinder generic manufacturing, leading to widespread availability and price erosion. Regulatory agencies have not issued new indications or significant label expansions since initial approval.

• Off-Label Use: Some clinicians prescribe RYTHMOL for neurological conditions like neuromas, but these are not officially approved uses.
• Regulatory Hurdles: Limited, as RYTHMOL is off-patent; however, concerns over cardiovascular safety profiles limit further development.

Competitive Landscape

Key competitors include:

Drug	Class	Market Position	Side Effect Profile
Amiodarone	Class III antiarrhythmic	Dominates in ventricular arrhythmia	Long-term toxicity concerns, drug interactions
Sotalol	Beta-blocker with class III activity	Widely used, lower cost	Torsades de pointes risk
Lidocaine	Na+ channel blocker, IV use	Emergency settings	Limited to acute care

RYTHMOL's niche use persists for patients intolerant to other treatments. Its low cost provides a competitive advantage in resource-limited settings.

Financial Trajectory and Outlook

Historical sales data indicate a decline:

• Peak Revenue (1990s): >$50 million/year (U.S. and Europe)
• Current Revenue (2022): Under $10 million/year, primarily from legacy prescriptions [2]
• Future Outlook: Minimal growth prospects absent new formulations, indication expansions, or technological advances.

Market analysts project continued decline, with potential for niche repositioning or combination therapy development, contingent on safety improvements.

Patent and Business Strategies

Given the patent expiry:

• Generic manufacturers dominate the supply chain.
• No major pharmaceutical company is actively investing in RYTHMOL reformulation, citing market saturation and safety concerns.
• Small biotechs have not pursued development due to limited profit potential and regulatory hurdles.

Summary of Financial Trends

Year	Estimated Revenue	Notes
2018	~$8 million	Steady decline since 2010
2020	~$7 million	No new indications, reduced market share
2022	<$10 million	Market stabilized domestically but shrinking globally

Key Challenges and Opportunities

• Challenges:

  • Outdated safety profile complicates regulatory approval for new uses.
  • Competition from newer drugs with improved safety.
  • Limited interest for R&D investment in an off-patent drug.

• Opportunities:

  • Niche use in refractory arrhythmias.
  • Potential label expansion with safety profile improvements.
  • Development of combination therapies.

Key Takeaways

• RYTHMOL faces a contracting market due to safety concerns, competition, and patent expiration.
• Its sales persist primarily through legacy prescribing, with ongoing decline.
• No active development pipeline exists; future financial gains are limited.
• The drug's position will remain niche unless safety or formulation innovations occur.

FAQs

1. Is RYTHMOL still approved for use in any indication?
Yes, it retains approval for the suppression of ventricular arrhythmias, but off-label prescribing exists.

2. Are there any ongoing clinical trials for RYTHMOL?
No significant trials have been registered recently; interest in RYTHMOL has waned.

3. How does RYTHMOL compare economically to alternatives?
It is generally less expensive than agents like amiodarone but has safety limitations that affect prescribing.

4. Can RYTHMOL be repositioned for new indications?
Potentially, but safety concerns and lack of incentives limit development efforts.

5. What is the outlook for generics of RYTHMOL?
Market saturation and declining sales diminish the commercial viability for new generic manufacturers.

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References

[1] Markets and Markets. (2023). Antiarrhythmic Drugs Market. Retrieved from https://www.marketsandmarkets.com

[2] Company financial disclosures and industry reports (2022–2023).