PLAQUENIL Drug Patent Profile

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

Plaquenil is a drug marketed by Advanz Pharma and is included in one NDA.

The generic ingredient in PLAQUENIL is hydroxychloroquine sulfate. There is one drug master file entry for this compound. Thirty-one suppliers are listed for this compound. Additional details are available on the hydroxychloroquine sulfate profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Plaquenil

A generic version of PLAQUENIL was approved as hydroxychloroquine sulfate by TEVA PHARMS on September 30^th, 1994.

Summary for PLAQUENIL

US Patents:	0
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	3
Raw Ingredient (Bulk) Api Vendors:	83
Clinical Trials:	106
Patent Applications:	5,010
Drug Prices:	Drug price information for PLAQUENIL
Drug Sales Revenues:	Drug sales revenues for PLAQUENIL
What excipients (inactive ingredients) are in PLAQUENIL?	PLAQUENIL excipients list
DailyMed Link:	PLAQUENIL at DailyMed

See drug prices for PLAQUENIL

See drug sales revenues for PLAQUENIL

Recent Clinical Trials for PLAQUENIL

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

Sponsor	Phase
Incannex Healthcare Ltd	Phase 2
Yoo-min Kim	Phase 3
Ministry of Health & Welfare, Korea	Phase 3

See all PLAQUENIL clinical trials

Pharmacology for PLAQUENIL

Drug Class

Antimalarial Antirheumatic Agent

US Patents and Regulatory Information for PLAQUENIL

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Advanz Pharma	PLAQUENIL	hydroxychloroquine sulfate	TABLET;ORAL	009768-001	Approved Prior to Jan 1, 1982	AB	RX	Yes	Yes

PLAQUENIL Market Dynamics, Financial Trajectory, Patent Position and Generic Competition

Last updated: August 27, 2026

Plaquenil, Sanofi’s brand of hydroxychloroquine sulfate, is a mature, off-patent pharmaceutical with durable demand in rheumatology, dermatology and malaria treatment. Its commercial value is driven by chronic autoimmune use rather than exclusivity. Generic hydroxychloroquine has structurally reduced pricing power, while the 2020 COVID-19 episode created a temporary demand and revenue spike that did not translate into durable brand growth.

Sanofi does not separately disclose global Plaquenil revenue in its current financial reporting. The product is grouped within broader established-pharmaceutical or general-medicine reporting categories. As a result, the financial trajectory must be assessed through product history, generic competition, prescription demand, public procurement, and Sanofi’s portfolio disclosures rather than a standalone audited revenue series.

What is Plaquenil and how is it used?

Plaquenil contains hydroxychloroquine sulfate, an antimalarial and immunomodulatory active ingredient. The principal approved uses are:

• Rheumatoid arthritis
• Systemic lupus erythematosus
• Discoid lupus erythematosus
• Malaria treatment and prophylaxis in susceptible regions

The product is administered orally, generally as 200 mg tablets in the United States. Its autoimmune indications generate recurring prescription demand because treatment can extend for years. Malaria demand is geographically concentrated and depends on resistance patterns, public-health procurement and the availability of alternative antimalarial medicines.

Hydroxychloroquine is pharmacologically related to chloroquine but has a different toxicity and tolerability profile. Long-term use requires ophthalmic monitoring because retinal toxicity is a recognized risk. The U.S. Food and Drug Administration has not approved hydroxychloroquine for COVID-19 treatment or prevention.[1]

How has Plaquenil’s financial trajectory developed?

Plaquenil’s financial trajectory has four distinct phases.

Period	Commercial condition	Financial effect
Pre-generic period	Branded hydroxychloroquine with limited direct substitution	Higher pricing and stronger brand economics
Generic-market period	Multiple manufacturers and pharmacy substitution	Lower prices and declining brand leverage
2020 COVID-19 surge	Stockpiling, emergency use, political attention and expanded prescribing	Temporary volume increase and supply pressure
Post-2020 normalization	FDA restrictions, clinical evidence against routine COVID-19 use and generic availability	Demand returned toward autoimmune and malaria indications

The brand’s strongest economic period was before generic competition became entrenched. Once multiple suppliers entered the market, hydroxychloroquine became a commodity-like oral solid with limited differentiation between branded and generic versions.

Sanofi’s public filings do not identify Plaquenil as a material standalone revenue contributor. The company reports at a portfolio level, and mature products such as Plaquenil are economically less important than Sanofi’s vaccines, specialty-care medicines and newer biologics. This limits the usefulness of estimating brand revenue from total company results.

Why did Plaquenil sales rise in 2020?

Demand increased sharply during the early COVID-19 period because physicians, hospitals, governments and consumers sought hydroxychloroquine despite limited evidence of benefit. The FDA issued an Emergency Use Authorization in March 2020 for certain hospitalized patients under specified conditions, then revoked that authorization in June 2020 after reviewing emerging evidence concerning lack of benefit and potentially serious cardiac risks.[2][3]

The 2020 increase was therefore event-driven rather than a durable expansion of the approved market. Purchases included inventory building and emergency procurement. After the FDA action and publication of negative or inconclusive clinical evidence, COVID-related demand receded.

Sanofi also donated or committed hydroxychloroquine supplies during the early pandemic response. Those activities increased public visibility but did not establish a sustainable commercial indication.[4]

When did Plaquenil lose market exclusivity?

Plaquenil no longer has meaningful U.S. market exclusivity. Hydroxychloroquine sulfate has been available from multiple generic manufacturers for many years, and the active ingredient is a mature small molecule with no current data-exclusivity barrier comparable to a recently approved medicine.

The relevant commercial conclusion is straightforward: a generic manufacturer can generally compete through an abbreviated new drug application, subject to FDA requirements for pharmaceutical equivalence, bioequivalence, manufacturing quality and labeling.

The brand may remain listed in regulatory databases, but listing does not imply effective exclusivity. Patent expiry, generic approvals and pharmacy substitution determine the practical market position.

What is the Orange Book status of Plaquenil?

Plaquenil is an FDA-approved small-molecule product. Its U.S. regulatory position is materially different from that of a protected new chemical entity or biologic:

• It is not dependent on biologic exclusivity.
• It does not have a biosimilar pathway.
• Generic competition is handled through the abbreviated new drug application pathway.
• Any active Orange Book-listed patent would need to be assessed against current FDA listings and the specific product strength.
• A product’s presence in the Orange Book does not by itself prevent generic entry.

The commercial significance of any residual formulation or method-of-use listing is limited where the core active ingredient and principal tablet presentation are already widely available from generic suppliers.

What patents protect Plaquenil and hydroxychloroquine?

The original composition and product patents associated with hydroxychloroquine are long expired. The commercially relevant intellectual-property position is therefore not the original molecule patent but any later patent covering:

• A particular formulation
• A manufacturing process
• A solid-state form
• A dosing regimen
• A specific therapeutic use
• A combination product
• A device or delivery system

For Plaquenil tablets, there is no apparent current patent barrier that prevents ordinary generic substitution in the United States. Method-of-use patents, where present, would not ordinarily block a generic from marketing the same drug for unpatented indications if the manufacturer uses appropriate labeling and complies with FDA requirements.

Are formulation patents a material risk?

Formulation patents are unlikely to create a material barrier for the conventional Plaquenil tablet market. Hydroxychloroquine sulfate is an established active ingredient, and generic products generally compete using standard immediate-release tablet formulations.

A new formulation could create a separate intellectual-property position if it delivered a clinically meaningful advantage, such as:

• Modified release
• Improved tolerability
• Pediatric dosing flexibility
• Reduced dosing frequency
• A combination with another active ingredient

Such products would compete in a differentiated niche and would not necessarily protect the legacy Plaquenil tablet franchise.

Which companies compete with Plaquenil?

The competitive market includes Sanofi’s brand and generic suppliers that manufacture or distribute hydroxychloroquine sulfate tablets. Market participants have included companies such as:

• Teva Pharmaceuticals
• Viatris and legacy Mylan businesses
• Sandoz
• Zydus Pharmaceuticals
• Rising Pharma
• Prasco Laboratories
• Other regional and contract manufacturers

The supplier set can change by strength, dosage form, country and procurement channel. FDA approval does not guarantee continuous commercial supply, and manufacturers may enter or exit based on pricing, shortages, manufacturing economics and wholesaler demand.

In the United States, pharmacy benefit managers and pharmacies commonly substitute generic hydroxychloroquine for the brand unless a prescriber specifies otherwise and the payer approves a brand exception. That substitution limits Plaquenil’s ability to maintain a premium price.

How does Plaquenil compare with competing autoimmune drugs?

Plaquenil is positioned as a low-cost conventional synthetic disease-modifying antirheumatic drug. It competes clinically with methotrexate, sulfasalazine, leflunomide and more advanced biologic or targeted synthetic therapies.

Product category	Examples	Relative market position
Hydroxychloroquine	Plaquenil and generics	Low-cost, long-term autoimmune therapy
Conventional DMARDs	Methotrexate, sulfasalazine, leflunomide	Broad rheumatoid arthritis use
Biologics	Adalimumab, etanercept, rituximab and others	Higher cost, generally used for more active or refractory disease
Targeted synthetic DMARDs	JAK inhibitors and related agents	Premium-priced, subject to safety and reimbursement controls

Hydroxychloroquine remains clinically relevant because it is inexpensive, orally administered and used in lupus management. It does not compete directly with specialty biologics on price or mechanism. Its market role is closer to a foundational or adjunctive therapy.

The principal commercial threat is not a new branded competitor. It is generic substitution and the migration of high-value treatment decisions toward specialty medicines when disease activity requires escalation.

What generic entry risks exist for Plaquenil?

Generic entry risk is already realized rather than prospective. The product faces five structural pressures:

1. Multiple approved suppliers reduce dependence on the Sanofi brand.
2. Generic substitution suppresses net pricing.
3. Payers have limited incentive to reimburse the brand.
4. Retail pharmacies can shift volume among manufacturers.
5. Manufacturing disruptions can change market share without changing underlying demand.

The remaining brand risks are therefore erosion, supply interruptions and reimbursement loss, not a single future patent cliff.

A generic manufacturer would face conventional barriers, including FDA approval, facility compliance, active-pharmaceutical-ingredient sourcing, quality control and commercial scale. Those are manufacturing and execution barriers, not durable exclusivity barriers.

What FDA regulatory issues affect Plaquenil?

The main FDA-related issues are safety, labeling and COVID-19 history.

Hydroxychloroquine labeling includes warnings and precautions concerning retinal toxicity, cardiomyopathy, QT prolongation, hypoglycemia, neuropsychiatric effects and serious dermatologic reactions.[1] These risks influence prescribing, monitoring and liability exposure.

The COVID-19 regulatory episode had three commercial consequences:

• It created short-term demand unrelated to the established product market.
• It increased scrutiny of cardiac safety and evidence quality.
• It reduced the likelihood that COVID-19 would become a lasting new indication.

The FDA’s revocation of the emergency authorization removed a major source of extraordinary demand.[3]

What litigation and settlement agreements affect Plaquenil?

There is no widely recognized current U.S. patent litigation campaign that materially threatens ordinary generic entry for Plaquenil. The product’s core patents are long expired, and the market is already populated by generic manufacturers.

The principal legal exposure has instead involved:

• Product-liability claims concerning retinal and cardiac risks
• False or misleading COVID-19 promotion allegations
• Regulatory compliance
• Supply and procurement disputes
• Commercial disputes over generic distribution

Patent settlements are not a central current market driver for hydroxychloroquine. Any new litigation involving a reformulated product, a combination therapy or a patented dosing regimen would need to be analyzed separately from the legacy Plaquenil tablet.

How strong is the Plaquenil patent estate?

The legacy patent estate is weak as a commercial exclusivity asset but strong in one narrower sense: the product has a long-established regulatory and clinical record.

Patent-estate factor	Assessment
Core molecule protection	Expired
Conventional tablet protection	No material current barrier apparent
New chemical entity exclusivity	Expired
Biosimilar protection	Not applicable
Generic substitution risk	High and already realized
Formulation differentiation	Limited for the legacy tablet
Manufacturing know-how	Relevant to quality and supply, not market exclusivity
Brand recognition	Useful but insufficient to sustain a large premium

Plaquenil’s enduring value comes from clinical familiarity, guideline use, physician experience and distribution, not from patent protection.

What is the geographic coverage and market outlook?

Hydroxychloroquine is sold across multiple international markets, but regulatory status, approved indications, reimbursement and generic penetration vary by country. In many markets, the active ingredient is supplied primarily through generic channels. Sanofi’s brand presence is stronger where physicians, hospitals or national procurement systems continue to specify the product.

The long-term outlook is stable to declining for the branded product and stable to modestly growing for the overall molecule market in autoimmune indications. Growth depends on:

• Prevalence and diagnosis of lupus and rheumatoid arthritis
• Continued use in combination treatment
• Access to rheumatology care
• Generic pricing
• Malaria treatment policy
• Competition from newer therapies

Revenue exposure for Sanofi is likely modest relative to its strategic growth products. For generic manufacturers, the opportunity is volume-based and price-sensitive. For investors, Plaquenil is better analyzed as a mature cash-flow and supply-chain product than as an innovation asset.

What are the likely generic launch scenarios?

The most likely scenario is continued multi-source generic supply with low brand pricing power. Three outcomes are commercially relevant:

Stable generic commodity market

Multiple suppliers remain active, prices stay competitive and autoimmune demand provides a recurring base. This is the baseline scenario.

Temporary shortage-driven pricing

A manufacturing interruption, API constraint or sudden procurement event could create short-term price increases or supplier share shifts. Such gains would be difficult to sustain once supply normalizes.

Differentiated reformulation

A manufacturer could develop a modified-release, pediatric or combination product with separate patent protection. That would create a new product opportunity but would not restore exclusivity to conventional Plaquenil.

Key Takeaways

• Plaquenil is a mature hydroxychloroquine sulfate brand with no meaningful remaining core patent exclusivity.
• Generic competition is established and is the main reason brand pricing power is limited.
• The 2020 COVID-19 demand surge was temporary and reversed after FDA action and unfavorable clinical evidence.
• Sanofi does not separately disclose current global Plaquenil revenue, so standalone financial modeling requires market-level assumptions.
• Long-term demand is anchored by lupus, rheumatoid arthritis, dermatology and malaria use.
• Biosimilar risk does not apply because hydroxychloroquine is a small-molecule drug.
• Formulation and method-of-use patents could protect future differentiated products but do not materially protect the legacy tablet franchise.
• The principal commercial risks are generic substitution, reimbursement pressure, manufacturing disruption and safety-related liability.

FAQs About Plaquenil Market and Patent Exposure

Is Plaquenil still a profitable drug for Sanofi?

Plaquenil may generate recurring revenue, but Sanofi’s public reporting does not identify it as a major standalone growth product. Its economic contribution is limited by generic substitution and mature-market pricing.

Can a generic manufacturer launch hydroxychloroquine without a patent settlement?

Yes. Because the core hydroxychloroquine market is off patent and already has generic suppliers, a new entrant generally does not need a settlement with Sanofi unless it seeks to market a separately patented formulation or indication.

Does Plaquenil have biosimilar competition?

No. Plaquenil is a small-molecule tablet. Its competitors are generic hydroxychloroquine products approved through the abbreviated new drug application pathway, not biosimilars.

Could a new lupus indication extend Plaquenil exclusivity?

A newly patented method of use could protect a specific indication if it met patentability requirements and was listed or enforced appropriately. It would not automatically restore exclusivity for existing hydroxychloroquine uses or block all generic sales.

Did COVID-19 create a permanent market for hydroxychloroquine?

No. COVID-19 created a temporary demand shock. FDA action and clinical evidence did not establish hydroxychloroquine as an approved or durable COVID-19 treatment market.[2][3]

References

1. U.S. Food and Drug Administration. (2023). Plaquenil (hydroxychloroquine sulfate) tablets: Prescribing information. FDA.

2. U.S. Food and Drug Administration. (2020, March 28). Emergency use authorization for hydroxychloroquine sulfate and chloroquine phosphate products. FDA.

3. U.S. Food and Drug Administration. (2020, June 15). FDA revokes emergency use authorization for chloroquine phosphate and hydroxychloroquine sulfate. FDA.

4. Sanofi. (2020, March 31). Sanofi donates Plaquenil to support COVID-19 response efforts. Sanofi.

5. Sanofi. (2024). Universal registration document and annual financial report 2023. Sanofi.

6. U.S. Food and Drug Administration. (2024). Drugs@FDA: FDA-approved drug products database. FDA.

DrugChatter Q&A for PLAQUENIL

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