ETHACRYNIC ACID Drug Patent Profile

Which patents cover Ethacrynic Acid, and when can generic versions of Ethacrynic Acid launch?

Ethacrynic Acid is a drug marketed by Adaptis, Agnitio, Alvogen, Amneal Pharms Co, Chartwell Rx, Hikma, Lupin Ltd, Ph Health, Sciegen Pharms, and Upsher Smith Labs. and is included in ten NDAs.

The generic ingredient in ETHACRYNIC ACID is ethacrynic acid. There are thirteen drug master file entries for this compound. Ten suppliers are listed for this compound. Additional details are available on the ethacrynic acid profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Ethacrynic Acid

A generic version of ETHACRYNIC ACID was approved as ethacrynic acid by ADAPTIS on June 30^th, 2016.

Summary for ETHACRYNIC ACID

US Patents:	0
Applicants:	10
NDAs:	10

US Patents and Regulatory Information for ETHACRYNIC ACID

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Adaptis	ETHACRYNIC ACID	ethacrynic acid	TABLET;ORAL	205609-001	Jun 30, 2016	AB	RX	No	No
Lupin Ltd	ETHACRYNIC ACID	ethacrynic acid	TABLET;ORAL	211719-001	Sep 6, 2019	AB	RX	No	No
Amneal Pharms Co	ETHACRYNIC ACID	ethacrynic acid	TABLET;ORAL	208805-001	May 8, 2018	AB	RX	No	No
Ph Health	ETHACRYNIC ACID	ethacrynic acid	TABLET;ORAL	208501-001	Jul 21, 2017		DISCN	No	No
Agnitio	ETHACRYNIC ACID	ethacrynic acid	TABLET;ORAL	211809-001	Jul 12, 2019	AB	RX	No	No
Alvogen	ETHACRYNIC ACID	ethacrynic acid	TABLET;ORAL	205709-001	Jul 24, 2018		DISCN	No	No

Ethacrynic Acid: Investment Fundamentals and Market Outlook

Last updated: February 19, 2026

Ethacrynic acid, a loop diuretic, presents a mature therapeutic with established efficacy but faces limited growth prospects due to generic competition and a narrow therapeutic window. Its primary utility remains in specific inpatient settings for edema management, particularly in patients unresponsive to thiazide diuretics. Patent expirations have rendered the active pharmaceutical ingredient (API) widely available and commoditized, impacting pricing power for manufacturers.

What is the Current Market Landscape for Ethacrynic Acid?

The global market for ethacrynic acid is characterized by its stability rather than rapid expansion. Demand is primarily driven by the ongoing need for effective treatments for fluid overload associated with conditions like congestive heart failure, cirrhosis, and renal disease. However, the market size is constrained by the drug's historical development timeline and the subsequent emergence of more modern diuretics with potentially improved safety profiles and administration routes.

According to market research reports, the ethacrynic acid market is estimated to be in the low hundreds of millions of dollars globally. This figure reflects the consistent, albeit slow, demand rather than a growth trajectory. For example, a 2023 report indicated a compound annual growth rate (CAGR) of less than 1% for the ethacrynic acid market over the next five years [1]. This low growth is a direct consequence of several factors:

• Generic Dominance: Ethacrynic acid has been off-patent for decades. This has led to a highly competitive generic market where price is the primary differentiator. Multiple manufacturers produce and distribute generic ethacrynic acid, driving down profit margins for individual companies.
• Therapeutic Alternatives: While ethacrynic acid remains a potent diuretic, newer drugs such as furosemide and torsemide offer comparable efficacy with different pharmacokinetic profiles and, in some cases, perceived advantages in tolerability. The availability of these alternatives limits the expansion of ethacrynic acid's patient base.
• Specific Indications: Its use is largely confined to acute, inpatient settings where rapid diuresis is critical and other agents have failed. This limits its prescription frequency and accessibility in outpatient settings.
• Adverse Event Profile: Ethacrynic acid has a known risk of ototoxicity, particularly at higher doses or with rapid intravenous administration [2]. This safety concern can deter its use in patients with pre-existing auditory issues or in long-term management strategies.

The primary manufacturers in the ethacrynic acid market are typically generic pharmaceutical companies specializing in producing APIs and finished dosage forms. These companies often operate on high-volume, low-margin models. Key players in the broader diuretic market, which would include ethacrynic acid suppliers, include Teva Pharmaceutical Industries, Mylan (now Viatris), and Apotex. However, for ethacrynic acid specifically, the market is fragmented among numerous regional and international generic manufacturers.

What is the Patent Status and Intellectual Property Protection for Ethacrynic Acid?

Ethacrynic acid was first patented in the early 1960s. The original patents have long since expired, meaning the compound itself is in the public domain. This lack of patent protection is a fundamental characteristic of its current market position.

• Original Patents: The foundational patents for ethacrynic acid, such as those held by Merck & Co. when it was initially developed, expired decades ago, likely in the 1980s or 1990s, aligning with typical patent lifespans of that era.
• No New Compound Patents: There are no active patents covering the ethacrynic acid molecule itself. This prevents any single company from holding exclusive rights to manufacture or sell the drug based on its chemical structure.
• Potential for Formulation Patents: While the API is generic, there could theoretically be opportunities for new intellectual property protection through novel drug delivery systems or formulations. For instance, a sustained-release formulation or a unique combination therapy incorporating ethacrynic acid could be patentable. However, no significant recent patent filings or approvals in this area have altered the market dynamics for the standard ethacrynic acid product.
• Abbreviated New Drug Applications (ANDAs): The pathway for generic entry in the United States is through ANDAs filed with the Food and Drug Administration (FDA). Companies seeking to market a generic version of ethacrynic acid submit these applications, demonstrating bioequivalence to the reference listed drug. Numerous ANDAs have been approved over the years, solidifying the generic nature of the market [3].

The absence of patent exclusivity means that any company can produce and sell ethacrynic acid provided they meet regulatory manufacturing standards and obtain necessary approvals. This has created a highly competitive environment where innovation is centered on cost-effective manufacturing and distribution rather than novel drug discovery or development related to the molecule itself.

What are the Manufacturing and Supply Chain Considerations for Ethacrynic Acid?

The manufacturing of ethacrynic acid API is a well-established chemical synthesis process. Given its long history, the synthesis routes are mature and have been optimized for cost and efficiency by numerous manufacturers globally.

• API Production: The primary manufacturers of ethacrynic acid API are often located in countries with strong chemical manufacturing bases, such as China and India. These facilities benefit from economies of scale and lower labor costs, allowing them to supply the API at competitive prices to formulators worldwide.
• Finished Dosage Forms: Formulation of ethacrynic acid into tablets and injectable solutions is undertaken by generic pharmaceutical companies. These companies source the API from API manufacturers and then produce the final drug products that are distributed to pharmacies and hospitals.
• Supply Chain Complexity: The supply chain for generic drugs like ethacrynic acid is global and can be subject to disruptions. Factors such as geopolitical events, raw material availability, shipping logistics, and regulatory changes in manufacturing countries can impact supply. However, due to the mature nature of the drug and the presence of multiple suppliers, significant long-term shortages are uncommon, though temporary localized issues can arise.
• Quality Control: Regulatory bodies such as the FDA and the European Medicines Agency (EMA) impose strict quality control measures on both API manufacturers and finished dosage form producers. Adherence to Good Manufacturing Practices (GMP) is mandatory. Companies must demonstrate consistency in purity, potency, and stability of their products.
• Regulatory Approvals: Manufacturers must obtain marketing authorization in each target country. This typically involves submitting dossiers detailing the manufacturing process, quality control data, and bioequivalence studies for generic products.

The established nature of ethacrynic acid manufacturing means that production capacity is generally sufficient to meet existing demand. The primary challenge for manufacturers is maintaining profitability in a price-sensitive market. Efficiency in synthesis, sourcing of raw materials, and streamlined distribution channels are critical for success.

What are the Clinical Applications and Therapeutic Value of Ethacrynic Acid?

Ethacrynic acid is a potent diuretic that acts on the thick ascending limb of the loop of Henle in the kidneys. It inhibits the sodium-potassium-chloride cotransporter (NKCC2), leading to increased excretion of sodium, chloride, potassium, and water.

• Primary Indication: Edema associated with congestive heart failure, hepatic cirrhosis, and renal disease, including the nephrotic syndrome [4]. It is particularly useful in patients who are refractory to other diuretics, such as thiazides.
• Mechanism of Action: It blocks the reabsorption of electrolytes in the kidney tubules, forcing the body to excrete more salt and water. This reduces fluid volume and blood pressure.
• Dosage and Administration: Ethacrynic acid is available in oral (tablets) and intravenous (for injection) formulations. Oral doses typically range from 50 mg to 200 mg per day, while intravenous doses are usually 0.5 mg to 1 mg/kg of body weight. Dosage is adjusted based on patient response and renal function.
• Efficacy: It is considered one of the most potent diuretics available. Its rapid onset of action, especially when administered intravenously, makes it valuable in acute situations requiring significant fluid removal.
• Adverse Effects: The most significant concern is ototoxicity, which can manifest as tinnitus (ringing in the ears) or hearing loss. This risk is dose-dependent and can be irreversible [2]. Other side effects include electrolyte imbalances (hyponatremia, hypokalemia, hypomagnesemia), hypotension, gastrointestinal upset, and hyperuricemia.
• Therapeutic Positioning: Ethacrynic acid is generally reserved for cases where other diuretics have proven insufficient or are contraindicated. Its use is often limited to short-term management or in specific inpatient scenarios due to its potent nature and potential for adverse events. It is not typically a first-line agent for chronic outpatient management of edema.

The therapeutic value of ethacrynic acid lies in its potent diuretic effect, offering a critical treatment option for patients with severe fluid overload who do not respond to less potent agents. However, its utility is tempered by its side effect profile, particularly the risk of ototoxicity, which necessitates careful patient selection and monitoring.

What are the Regulatory and Safety Considerations for Ethacrynic Acid?

Regulatory oversight for ethacrynic acid is primarily handled by national health authorities like the FDA in the United States and the EMA in Europe. These bodies regulate its manufacturing, marketing, and post-market surveillance.

• FDA Approval: Ethacrynic acid is approved by the FDA for its indicated uses. Generic versions must demonstrate bioequivalence to the innovator product, Edecrin (Merck), which was first approved in 1967 [3].
• Pharmacovigilance: Post-market surveillance continuously monitors the safety of approved drugs. The FDA collects adverse event reports through its MedWatch program. For ethacrynic acid, the most frequently reported serious adverse event is ototoxicity [2, 5].
• Labeling Requirements: Product labeling must include comprehensive information on indications, contraindications, warnings, precautions, adverse reactions, and drug interactions. Warnings regarding the potential for hearing impairment are prominently featured.
• Manufacturing Standards: As mentioned, all manufacturers must adhere to current Good Manufacturing Practices (cGMP) to ensure product quality, safety, and efficacy. Regular inspections of manufacturing facilities are conducted by regulatory agencies.
• Orphan Drug Status: Ethacrynic acid does not currently hold orphan drug designation for any indication, meaning it is not eligible for the incentives associated with rare disease treatments.
• REMS Programs: The FDA may require Risk Evaluation and Mitigation Strategies (REMS) for drugs with significant safety concerns. While ethacrynic acid has a known risk profile, a specific REMS program is not currently mandated for the drug as a whole, though individual prescribing guidelines often emphasize careful patient selection and monitoring.

The regulatory landscape for ethacrynic acid is mature and well-defined. The focus of regulatory action and attention remains on ensuring manufacturing quality and monitoring for its known adverse event profile, particularly ototoxicity.

What are the Investment Opportunities and Risks Associated with Ethacrynic Acid?

Investing in ethacrynic acid at this stage of its lifecycle presents a unique set of opportunities and risks, primarily centered on the generic pharmaceutical manufacturing sector.

Investment Opportunities

• Stable, Non-Discretionary Demand: Edema management remains a critical healthcare need. Ethacrynic acid, despite its limitations, continues to be a necessary treatment for a subset of patients, ensuring a baseline level of demand.
• Low R&D Burden: For generic manufacturers, the R&D investment is minimal, primarily focused on process optimization and ensuring regulatory compliance, not novel drug discovery. This lowers the barrier to entry and reduces the risk of clinical trial failures.
• Cost-Effective Manufacturing: Companies with highly efficient API synthesis and formulation capabilities can achieve competitive cost structures, allowing for profitability even in a low-margin environment.
• Global Market Access: With long-expired patents, ethacrynic acid can be manufactured and sold in virtually any market where generic drugs are permitted, offering broad geographic reach.
• Potential for Supply Chain Optimization: Investors can identify companies that have optimized their supply chains for cost and reliability, ensuring consistent product availability which is crucial in the generic market.

Investment Risks

• Price Erosion and Margin Compression: Intense competition among generic manufacturers leads to significant price pressure. Profit margins are thin and can be further eroded by larger players or new entrants.
• Limited Growth Potential: The market for ethacrynic acid is mature and is not expected to grow significantly. Any investment must be predicated on market share gains or operational efficiency, not market expansion.
• Regulatory Scrutiny and Compliance Costs: While R&D is low, maintaining compliance with cGMP and evolving regulatory requirements can be costly and complex. Any regulatory misstep can lead to product recalls or manufacturing shutdowns.
• Therapeutic Obsolescence: While unlikely to disappear entirely due to its potency, newer diuretics or alternative treatments for edema could slowly diminish its market share over the very long term.
• Supply Chain Vulnerabilities: Reliance on specific regions for API production or potential disruptions in global logistics can impact availability and profitability.
• Ototoxicity Concerns: While not a direct investment risk for established generics, any heightened regulatory scrutiny or reclassification due to ototoxicity could indirectly impact demand or manufacturing requirements.

For an investment thesis, the focus would be on companies with strong operational efficiencies, established global distribution networks, robust quality control systems, and a competitive cost of goods sold. The investment would be in the manufacturing and supply of a commoditized, essential medicine rather than in the prospect of novel therapeutic advancement.

Key Takeaways

Ethacrynic acid is a mature, potent loop diuretic with stable but low-growth market demand. Its therapeutic value is established for specific edema management scenarios, particularly in inpatient settings or when other diuretics fail. The absence of patent protection has resulted in a highly competitive generic market characterized by price sensitivity and thin profit margins. Key manufacturing and supply chain considerations revolve around cost-effective API production, global distribution, and strict adherence to cGMP standards. Regulatory oversight focuses on manufacturing quality and pharmacovigilance of its known side effect profile, notably ototoxicity. Investment opportunities lie in the stable demand for essential medicine and the potential for operational efficiencies in generic manufacturing, while risks are primarily associated with intense price competition, limited growth, and regulatory compliance.

Frequently Asked Questions

1. Is there any ongoing research into new therapeutic uses for ethacrynic acid? While ethacrynic acid's primary use as a diuretic is well-established, there has been limited recent research exploring novel applications. Some academic studies have investigated its potential in other areas, such as its effects on certain cellular processes, but these have not translated into significant clinical development or new therapeutic indications. The focus remains on its established role in managing edema.

2. What are the primary drivers of demand for ethacrynic acid in current healthcare systems? The primary drivers of demand are the persistent prevalence of conditions causing fluid overload, such as congestive heart failure, cirrhosis of the liver, and renal disease. Ethacrynic acid is particularly sought after when patients are resistant to or intolerant of other diuretic classes, making it a critical option for a specific, albeit limited, patient population.

3. How does the manufacturing cost of ethacrynic acid compare to newer diuretics? Due to its long history and established synthesis routes, the manufacturing cost of ethacrynic acid API is generally lower than that of newer, more complex diuretic molecules. This cost advantage is a significant factor in its continued availability as an affordable generic option.

4. What is the typical patient profile for whom ethacrynic acid is prescribed? Ethacrynic acid is typically prescribed for adult patients experiencing significant edema that has not responded to less potent diuretics like thiazides. It is often used in hospital settings for acute management of fluid overload. Patients with severe renal impairment may also benefit from its potent action. However, due to the risk of ototoxicity, it is generally avoided in patients with hearing impairment or those requiring long-term, daily diuretic therapy without strict medical supervision.

5. Beyond ototoxicity, what other significant safety concerns are associated with ethacrynic acid? Beyond ototoxicity, significant safety concerns include electrolyte imbalances such as hypokalemia (low potassium), hyponatremia (low sodium), and hypomagnesemia (low magnesium), which can lead to arrhythmias and other complications. Hypotension (low blood pressure) is also a risk, particularly with intravenous administration. Gastrointestinal disturbances like nausea and diarrhea are common.

Cited Sources

1. Grand View Research. (2023). Diuretics Market Size, Share & Trends Analysis Report By Drug Class (Loop Diuretics, Thiazides, Potassium-Sparing, Others), By Indication (Hypertension, Edema, Others), By Region, And Segment Forecasts, 2024 - 2030.
2. Brieger, W. J., & Miller, P. L. (1985). Ototoxicity of ethacrynic acid. Archives of Otolaryngology–Head & Neck Surgery, 111(4), 273-274.
3. U.S. Food & Drug Administration. (n.d.). Drugs@FDA. Retrieved from https://www.accessdata.fda.gov/scripts/cder/daf/
4. U.S. National Library of Medicine. (n.d.). Ethacrynic Acid. Retrieved from https://medlineplus.gov/druginfo/meds/a682030.html
5. Cuppoletti, J., & Slizeski, M. J. (2006). Ototoxicity of loop diuretics. The American Journal of the Medical Sciences, 331(4), 210-216.