Auranofin - Generic Drug Details

What are the generic drug sources for auranofin and what is the scope of freedom to operate?

Auranofin is the generic ingredient in one branded drug marketed by Legacy and is included in one NDA. Additional information is available in the individual branded drug profile pages.

Two suppliers are listed for this compound.

Summary for auranofin

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	2
Raw Ingredient (Bulk) Api Vendors:	34
Clinical Trials:	14
What excipients (inactive ingredients) are in auranofin?	auranofin excipients list
DailyMed Link:	auranofin at DailyMed

Recent Clinical Trials for auranofin

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

Sponsor	Phase
Federal University of So Paulo	PHASE2
Conselho Nacional de Desenvolvimento Cientfico e Tecnolgico	PHASE2
University of Ulm	Phase 1/Phase 2

See all auranofin clinical trials

Medical Subject Heading (MeSH) Categories for auranofin

Antirheumatic Agents

Anatomical Therapeutic Chemical (ATC) Classes for auranofin

M01CB	Gold preparations
M01C	SPECIFIC ANTIRHEUMATIC AGENTS
M01	ANTIINFLAMMATORY AND ANTIRHEUMATIC PRODUCTS
M	Musculo-skeletal system

US Patents and Regulatory Information for auranofin

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Legacy	RIDAURA	auranofin	CAPSULE;ORAL	018689-001	May 24, 1985		RX	Yes	Yes

Expired US Patents for auranofin

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Legacy	RIDAURA	auranofin	CAPSULE;ORAL	018689-001	May 24, 1985
Legacy	RIDAURA	auranofin	CAPSULE;ORAL	018689-001	May 24, 1985
Legacy	RIDAURA	auranofin	CAPSULE;ORAL	018689-001	May 24, 1985
Legacy	RIDAURA	auranofin	CAPSULE;ORAL	018689-001	May 24, 1985
Legacy	RIDAURA	auranofin	CAPSULE;ORAL	018689-001	May 24, 1985

Auranofin Market Dynamics and Financial Trajectory

Last updated: September 4, 2026

Auranofin is a mature oral gold compound with FDA approval for rheumatoid arthritis under the brand name Ridaura. Its original commercial opportunity has largely expired: composition-of-matter and early-use patent protection ended decades ago, no active U.S. Orange Book patent estate is central to the product, and the drug has limited current commercial visibility. Its financial value now depends on niche supply, specialty pricing, repurposing research, and manufacturing access rather than conventional branded exclusivity.

What is auranofin and what is its FDA status?

Auranofin is an orally administered gold-containing disease-modifying antirheumatic drug. Ridaura contains 3 mg auranofin per capsule and received U.S. FDA approval in 1985 for treatment of adults with rheumatoid arthritis who had an inadequate response to, or could not tolerate, nonsteroidal anti-inflammatory drugs.[1]

Attribute	Auranofin
Active ingredient	Auranofin
Brand	Ridaura
Dosage form	3 mg oral capsule
Original indication	Rheumatoid arthritis
U.S. approval	1985
FDA pathway	Original NDA
Drug class	Gold-containing DMARD
Current commercial position	Mature, niche, limited visibility
Biosimilar relevance	None
Generic pathway	Abbreviated New Drug Application, subject to FDA requirements

Auranofin is pharmacologically distinct from injectable gold salts because it is administered orally. Its use declined as methotrexate, biologic DMARDs, and targeted synthetic DMARDs became standard rheumatoid arthritis therapies. Current American College of Rheumatology treatment guidelines prioritize conventional synthetic DMARDs such as methotrexate and newer biologic or targeted agents over oral gold therapy.[2]

The FDA approval remains important because it provides a regulatory foundation for the rheumatoid arthritis indication. Approval does not establish current availability, commercial success, or an active period of market exclusivity.

When did auranofin lose exclusivity?

Auranofin lost meaningful branded exclusivity many years ago. The product is a small-molecule drug approved in 1985, so any ordinary U.S. patent protection associated with its original development would have expired no later than the late 2000s, assuming standard 20-year patent terms and any available patent-term adjustment or extension.

The practical exclusivity timeline is as follows:

Period	Commercial event
Before 1985	Development of oral gold therapy and preapproval clinical testing
1985	FDA approval of Ridaura
Late 1980s to 1990s	Branded rheumatoid arthritis commercialization
1990s to 2000s	Declining clinical use as methotrexate and biologic therapies gained adoption
By the late 2000s	Original patent-based exclusivity would generally have expired
2010s onward	Niche, supply-constrained, generic or legacy-brand market
Current period	Value driven by availability, pricing, and repurposing interest

What patents protect auranofin?

The original auranofin patent estate is no longer a meaningful barrier to U.S. generic entry. Any historic composition, synthesis, formulation, or rheumatoid arthritis use patents would have expired long before the current period.

No active, commercially important Orange Book patent estate is generally associated with Ridaura today. The relevant protection profile is therefore different from products with listed patents covering formulations, delivery devices, crystal forms, or dosing regimens.

Potential later patents could still cover:

• New indications, such as oncology or infectious disease uses.
• Specific dosing schedules.
• Combination regimens.
• Novel formulations or delivery systems.
• Manufacturing processes.
• Biomarker-defined patient populations.

These patents would not recreate broad exclusivity for auranofin itself. They could support narrower method-of-use or formulation businesses if the claims are valid, enforceable, and commercially relevant.

What is the Orange Book status of auranofin?

Auranofin has no known current Orange Book listing that creates a significant barrier to an ANDA applicant. The relevant FDA record is the original NDA and its labeling history, rather than an active patent dispute involving listed patents.

The commercial implications are direct:

1. A generic applicant would not normally face a substantial patent-delay risk from a Paragraph IV challenge.
2. A Paragraph IV certification would have limited strategic value if no relevant listed patent remains.
3. FDA approval would still require pharmaceutical equivalence, bioequivalence, chemistry, manufacturing and controls documentation, and adequate product quality.
4. Market entry could remain difficult even without patent barriers because the market is small and product supply may be unreliable.

Patent expiration and market entry are separate questions. Auranofin illustrates a mature drug where regulatory and manufacturing economics are more important than patent enforcement.

How many patents cover auranofin?

The number of historic patents related to auranofin cannot be equated with the number of active commercial barriers. The original compound and use rights are old, and the current value of those patents is effectively exhausted in the United States.

A current diligence review should distinguish among:

Patent category	Present commercial significance
Original compound patents	Expired
Original rheumatoid arthritis use patents	Expired
Historic synthesis patents	Generally expired
Later repurposing patents	Potentially relevant only to narrow indications
Formulation patents	Relevant only if an enforceable, marketed formulation exists
Manufacturing know-how	May remain commercially important even without patent protection
Trade secrets	Could affect cost, quality, and supply continuity

For auranofin, manufacturing know-how may create a stronger practical barrier than patent rights. Gold-containing chemistry requires controlled raw materials, validated impurity profiles, and consistent capsule production. A small market may not justify investment by multiple manufacturers.

What is the market size and competitive landscape for auranofin?

Auranofin operates in a narrow legacy market rather than a growth pharmaceutical category. Its rheumatoid arthritis competitors include:

• Methotrexate, the dominant conventional synthetic DMARD.
• Hydroxychloroquine and sulfasalazine.
• Leflunomide.
• Tumor necrosis factor inhibitors.
• Interleukin-6 inhibitors.
• T-cell costimulation modulators.
• Janus kinase inhibitors.

Auranofin is disadvantaged by its safety and monitoring profile. Reported adverse effects include diarrhea, skin reactions, stomatitis, proteinuria, cytopenias, and other manifestations of gold toxicity. The product label requires monitoring for hematologic, renal, and other adverse effects.[1]

Competitive factor	Auranofin position
Oral administration	Positive
Clinical familiarity	Historical but declining
First-line guideline position	Weak
Cost of active ingredient	Potentially manageable
Manufacturing complexity	Moderate to high relative to market size
Monitoring burden	Material
Generic competition	Legally feasible
Demand growth	Low
Repurposing interest	Higher than rheumatoid arthritis demand, but unproven commercially

The product’s market is likely concentrated in patients who cannot use standard therapies, physicians with familiarity with older DMARDs, and jurisdictions or institutions where treatment options differ from U.S. practice.

Public sources do not provide a reliable, standalone current revenue series for auranofin. The product is not reported as a major revenue line by a diversified pharmaceutical company, and available prescription or pricing databases may not capture private-label, specialty-distribution, or intermittent supply activity consistently.

What is auranofin’s financial trajectory?

Auranofin’s financial trajectory has four distinct phases.

1. Branded growth after FDA approval

The initial revenue opportunity came from differentiated oral gold therapy for rheumatoid arthritis. Auranofin offered an alternative to injectable gold products and other older DMARDs. Commercial value was linked to the size of the rheumatoid arthritis population and the limited treatment options available in the 1980s.

2. Structural decline after therapeutic substitution

Revenue declined as methotrexate became the anchor conventional DMARD and biologic therapies expanded. Auranofin’s slower onset, safety monitoring, and toxicity profile reduced physician demand.

3. Post-exclusivity erosion

Once patent and regulatory exclusivity ended, the product became vulnerable to generic or low-cost competition. However, the market did not develop into a high-volume generic category. The limited patient population and declining use reduced the incentive for multiple manufacturers to compete.

4. Niche pricing and repurposing optionality

Later commercial value has depended on scarcity, supply continuity, and potential new indications. Research has examined auranofin in oncology, parasitic disease, viral disease, and other conditions. These programs may support new patents or licensing opportunities, but clinical research interest has not translated into a broadly validated commercial franchise.

The financial profile is therefore asymmetric:

Value driver	Assessment
Legacy rheumatoid arthritis revenue	Low and declining
Current branded premium	Limited
Generic volume opportunity	Small
Scarcity pricing potential	Possible but unstable
Repurposing upside	Scientifically plausible, commercially unproven
Licensing value	Primarily dependent on clinical validation
Manufacturing value	Potentially significant in a constrained market
Litigation value	Low absent an active patent estate

Which companies are challenging auranofin exclusivity?

There is no prominent current Paragraph IV campaign comparable to challenges involving high-revenue branded drugs. Auranofin’s historic exclusivity has already expired, and the commercial opportunity is too limited to support a major public patent contest.

Generic competition is more likely to arise through:

• A conventional ANDA relying on reference-product data.
• A limited-distribution generic.
• A regional manufacturer.
• A repurposing company seeking a new indication rather than a rheumatoid arthritis market.
• A compounding or specialty supply arrangement, subject to applicable law.

The principal entry risk is not a patent injunction. It is whether a manufacturer can achieve acceptable economics, obtain reliable gold-containing API, meet quality requirements, and sell enough product to recover development and compliance costs.

What formulation and manufacturing patents could protect auranofin?

Auranofin’s most relevant future IP opportunities would involve improvements rather than the original active ingredient.

Formulation patents

Potential claims could cover:

• Improved capsule stability.
• Protection from moisture or oxidation.
• Reduced gastrointestinal toxicity.
• Modified-release delivery.
• Alternative oral dosage forms.
• Combination products with other DMARDs.
• Improved bioavailability or reduced variability.

A formulation patent would need to provide a clinically meaningful advantage. A minor excipient change would have limited commercial value unless it produced a measurable stability, safety, or pharmacokinetic benefit.

Method-of-use patents

New indications could support method-of-use claims if clinical data demonstrate efficacy. Repurposing research has investigated auranofin’s effects on thiol-dependent enzymes, redox pathways, inflammatory mechanisms, and certain pathogens.[3][4]

Method-of-use claims can provide commercial protection even when the molecule is generic. Their strength depends on:

• The specificity of the patient population.
• The required dose and treatment duration.
• Clinical support.
• Physician adoption.
• Whether the patented indication can be carved out of a generic label.
• The ability to detect and enforce infringement.

Manufacturing and process protection

Process patents and trade secrets may reduce production costs or improve purity. They are less likely to block all generic entry than a composition patent, but they can affect supply reliability and gross margin.

Does auranofin have biosimilar risk?

Auranofin has no biosimilar risk because it is a chemically synthesized small molecule, not a biologic. The relevant competitive pathway is generic substitution, not biosimilar interchangeability.

The distinction matters commercially:

Issue	Auranofin
Regulatory competition	ANDA generics
Biosimilar pathway	Not applicable
Interchangeability designation	Not applicable
Reference product	Ridaura or applicable FDA reference listing
Primary barrier	Product quality, supply, and economics

What licensing deals affect auranofin?

No major current licensing transaction is publicly established as a principal driver of auranofin’s value. The most plausible licensing model is a repurposing deal in which a research company licenses a new indication, formulation, or combination therapy.

Potential deal structures would include:

• Option agreements tied to proof-of-concept data.
• Regional rights for a new indication.
• Milestone payments after clinical or regulatory events.
• Royalty arrangements on a formulation or method-of-use product.
• Supply agreements linked to a qualified API source.

A license covering only the old rheumatoid arthritis indication would have limited economic value. A deal would require differentiated clinical data, enforceable claims, or a supply advantage.

What generic launch scenarios exist for auranofin?

Three launch scenarios are commercially credible.

Low-volume generic entry

A manufacturer launches a standard 3 mg capsule with limited inventory. This scenario creates price competition but may not materially expand the market.

Specialty-supply model

A single supplier maintains the product for hospitals, rheumatologists, or specialty pharmacies. Pricing may remain elevated because the supplier supports a small, compliance-heavy market.

Repurposed-product launch

A sponsor develops auranofin for a new disease and relies on method-of-use, formulation, orphan-drug, or other regulatory incentives. This scenario has the greatest upside but also the highest clinical and regulatory risk.

What geographic markets matter for auranofin?

The United States remains relevant because of the historical FDA approval and established reference-product record. Europe, Canada, Australia, and other markets may have separate marketing authorizations, reimbursement rules, and availability patterns.

Geographic value is constrained by:

• National withdrawal or discontinuation decisions.
• Different generic approval standards.
• Local gold-compound prescribing patterns.
• Reimbursement limits.
• API import and quality requirements.
• Pharmacovigilance obligations.

A product may be legally approved in a jurisdiction but commercially unavailable because the manufacturer no longer supplies it.

How strong is the auranofin patent estate?

Auranofin has a weak legacy patent estate and limited current exclusivity strength.

Criterion	Assessment
Composition-of-matter protection	Expired
Active Orange Book protection	Not a material barrier
Formulation protection	Limited or not commercially central
Method-of-use protection	Possible only for later indications
Manufacturing protection	Potentially relevant, but narrow
Generic litigation exposure	Low
Repurposing IP potential	Moderate, dependent on clinical data
Overall patent strength	Weak for legacy use; potentially stronger for validated new uses

Key Takeaways

• Auranofin was FDA-approved as Ridaura in 1985 for rheumatoid arthritis.
• Its original patent-based exclusivity ended decades ago.
• No major active Orange Book patent barrier is central to the current U.S. market.
• Auranofin has no biosimilar risk; competition would proceed through generic pathways.
• Rheumatoid arthritis demand declined because methotrexate, biologics, and targeted therapies displaced oral gold treatment.
• Current revenue is niche and is not transparently reported as a standalone public financial line.
• Manufacturing economics, API access, and supply continuity may matter more than patents.
• The principal upside is repurposing for new indications, formulations, or combinations.
• A new method-of-use or formulation patent could protect a commercial program, but it would not restore broad molecule-level exclusivity.
• Generic entry risk is legally high and financially moderate because the market is small.

FAQs About Auranofin Market Value and Exclusivity

Is auranofin still sold in the United States?

Auranofin has an FDA-approved product history, but commercial availability has been limited and may vary by supplier and period. Approval status should be distinguished from active, continuous market supply.

What is the current price of Ridaura?

There is no single stable market price. Pricing can vary substantially based on supplier, pharmacy channel, insurance coverage, inventory, and whether the product is branded, generic, or obtained through a specialty supply arrangement.

Can a generic manufacturer launch auranofin without patent litigation?

Potentially. The absence of a meaningful active Orange Book patent barrier reduces litigation risk, but an ANDA applicant would still need to satisfy FDA requirements for pharmaceutical equivalence, bioequivalence, manufacturing quality, and labeling.

Could auranofin become valuable through cancer repurposing?

Yes, but only if clinical studies establish a commercially meaningful benefit and the sponsor secures enforceable indication, formulation, or combination claims. Preclinical activity alone does not support a reliable revenue forecast.

Is auranofin an orphan drug?

Auranofin’s original rheumatoid arthritis approval was not based on orphan-drug exclusivity. A future sponsor could seek orphan designation for a qualifying rare disease, but designation and approval would require meeting FDA statutory and clinical criteria.

References

1. U.S. Food and Drug Administration. (1985). Ridaura (auranofin) capsules prescribing information. FDA.

2. Fraenkel, L., Bathon, J. M., England, B. R., St. Clair, E. W., Arayssi, T., Carandang, K., et al. (2021). 2021 American College of Rheumatology guideline for the treatment of rheumatoid arthritis. Arthritis Care & Research, 73(7), 924-939.

3. Roder, C., & Thomson, M. J. (2015). Auranofin: Repurposing an old drug for a golden new age. Drugs in R&D, 15(1), 13-20.

4. U.S. National Library of Medicine. (n.d.). Auranofin. PubChem Compound Summary. National Center for Biotechnology Information.

5. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. FDA, Center for Drug Evaluation and Research.