Last updated: August 1, 2026

Sulfadiazine sodium is a mature, low-volume generic antimicrobial used mainly when sulfadiazine is required and oral administration is impractical. Its commercial profile is defined by limited demand, low pricing power, hospital procurement, intermittent supply risk, and the absence of meaningful branded exclusivity. Public sources do not disclose product-level revenue for sulfadiazine sodium, so a reliable standalone sales forecast cannot be established. The financial trajectory is best characterized as stable but small, with earnings determined by supply continuity, manufacturing economics, and institutional contracts rather than market expansion.

What is sulfadiazine sodium and how is it used?

Sulfadiazine sodium is the water-soluble sodium salt of sulfadiazine, a sulfonamide antibacterial agent. It inhibits bacterial folate synthesis through competition with para-aminobenzoic acid. The drug is used against susceptible organisms and has an established role in toxoplasmosis treatment when combined with pyrimethamine and folinic acid, although modern treatment decisions depend on clinical circumstances and available alternatives.

Sulfadiazine sodium is distinct from:

Sulfadiazine tablets, an oral formulation.
Sulfasalazine, an anti-inflammatory and immunomodulatory drug.
Silver sulfadiazine, a topical burn treatment.
Sulfamethoxazole, commonly used with trimethoprim.

The sodium salt’s principal commercial rationale is formulation flexibility. Intravenous administration can be relevant when a patient cannot take oral medication, but the narrower use case limits volume compared with broad-spectrum hospital antibiotics.

What is the FDA regulatory status of sulfadiazine sodium?

Sulfadiazine sodium is an established generic active pharmaceutical ingredient rather than a newly developed drug. Its regulatory value comes from an abbreviated or legacy approval pathway, manufacturing compliance, and continued availability.

The key regulatory characteristics are:

Attribute	Assessment
Drug category	Generic sulfonamide antibacterial
FDA pathway	Legacy/generic approval framework, depending on product and sponsor
New chemical entity exclusivity	Expired
Orphan-drug exclusivity	No broad product-level exclusivity identified
Pediatric exclusivity	No current product-specific period identified
Regulatory differentiation	Primarily formulation, supply, quality, and labeling execution
Commercial channel	Hospitals, specialty pharmacies, wholesalers, and government procurement
Revenue disclosure	No public standalone revenue typically reported

FDA’s Orange Book remains the primary source for approved multisource drug products and listed patents. For an old generic such as sulfadiazine sodium, the commercial question is usually whether an active approved product is available and competitively supplied, not whether a branded patent remains enforceable.[1]

When does sulfadiazine sodium lose exclusivity?

Sulfadiazine sodium has no meaningful remaining original-drug exclusivity. The underlying sulfonamide chemistry has been commercially established for decades, and any original composition-of-matter or early use patents would have expired long ago.

Current commercial protection does not depend on patent exclusivity. It depends on:

FDA approval and manufacturing compliance.
Drug-master-file or process know-how.
Supplier qualification by hospitals and wholesalers.
Reliable access to active pharmaceutical ingredient.
Sterile manufacturing capability for injectable products.
Contract pricing and inventory management.

A sponsor could hold a later patent on a specific formulation, process, container, or delivery system. Such a patent would protect only the claimed technology and would not restore exclusivity to sulfadiazine sodium generally.

What patents protect sulfadiazine sodium?

No material live patent barrier is expected to protect the basic sulfadiazine sodium molecule. The relevant patent categories would be:

Composition patents

The original compound and salt-related patent position is historical. These rights are not a practical barrier to generic manufacture.

Method-of-use patents

Potential method-of-use claims could cover a defined patient population, dosing regimen, or combination therapy. Such claims would have limited commercial reach because sulfadiazine’s principal uses are established and generic treatment protocols are widely known.

Formulation patents

A later patent could claim:

A stable injectable formulation.
A specific concentration or pH range.
An excipient system.
A preservative-free presentation.
A vial, ampoule, or ready-to-use container.
A manufacturing or sterilization process.

Any such rights would need to be assessed claim by claim. They would not necessarily prevent sale of a non-infringing sulfadiazine sodium formulation.

Manufacturing and quality barriers

For an injectable product, manufacturing execution can create a stronger practical barrier than patents. Sterility assurance, particulate control, container closure integrity, validated aseptic processing, and stability data increase the cost and time required for entry.

How many patents cover sulfadiazine sodium?

The number of commercially relevant active patents is likely minimal. A reliable count requires a current, claim-level search across the USPTO, WIPO, European Patent Office, and national registers, followed by expiration and legal-status review.

The more important conclusion is that sulfadiazine sodium is not an innovation-led patent market. Its competitive barriers are operational:

API sourcing.
Injectable capacity.
Regulatory maintenance.
Small-batch economics.
Hospital formulary acceptance.
Shortage response capability.

This profile differs from newer anti-infective products, where formulation patents, regulatory exclusivities, and branded clinical positioning can support premium pricing.

Are there Paragraph IV challenges for sulfadiazine sodium?

Paragraph IV litigation is unlikely to be a major current market driver. Paragraph IV certifications apply when an abbreviated new drug application applicant challenges Orange Book-listed patents for a reference product. For an old generic molecule with limited listed-patent value, the probability of commercially significant Paragraph IV litigation is low.

The practical competitive sequence is more likely to involve:

A generic sponsor filing or maintaining approval.
FDA review of chemistry, manufacturing, and controls.
Commercial launch after approval and supply qualification.
Price competition among a small number of suppliers.
Periodic market tightening if one manufacturer exits or experiences a quality problem.

The absence of active patent litigation does not eliminate commercial risk. A supplier can lose share through manufacturing interruption, FDA action, wholesaler delisting, or hospital substitution.

What is the Orange Book status of sulfadiazine sodium?

The Orange Book should be reviewed at the product level because sulfadiazine, sulfadiazine sodium, dosage form, strength, and sponsor may appear under separate records. The database identifies approved products, therapeutic-equivalence information, and listed patents where applicable.[1]

For market analysis, the relevant questions are:

Is the specific sulfadiazine sodium dosage form currently approved?
Is the product actively marketed or listed as discontinued?
Are there therapeutically equivalent products?
Are patents or exclusivity codes listed?
Is the dosage form injectable, oral, or another presentation?

A discontinued listing can have commercial importance. It may indicate that demand is too low for the sponsor’s manufacturing economics, even if the active ingredient remains clinically useful.

What is the market size for sulfadiazine sodium?

No dependable public market-size figure is generally available for sulfadiazine sodium as a standalone product. Commercial databases may combine:

Sulfadiazine and sulfadiazine sodium.
Oral and injectable presentations.
U.S. and international sales.
Hospital and retail channels.
Product sales with broader sulfonamide categories.

Those aggregations can materially overstate the addressable market for sulfadiazine sodium itself.

The market is likely characterized by:

Market factor	Effect on sulfadiazine sodium
Patient population	Narrow and episodic
Prescriber base	Infectious-disease specialists, hospitals, and specialty providers
Volume	Low relative to common antibiotics
Pricing	Generic and procurement-driven
Demand growth	Limited
Substitution	Possible when clinically appropriate
Supply sensitivity	High if few qualified manufacturers remain
Promotional activity	Minimal
Reimbursement leverage	Low to moderate, depending on setting

The product’s value can rise temporarily during shortages or when alternatives are unsuitable. That does not necessarily translate into durable market growth.

What drives the financial trajectory of sulfadiazine sodium?

The product’s financial trajectory is determined by unit economics rather than prescription expansion.

Revenue drivers

Revenue can improve through:

A supplier exit that reduces competition.
A temporary shortage affecting competing products.
New hospital contracts.
Availability of an injectable presentation where oral administration is unsuitable.
Price increases linked to small-batch or sterile-manufacturing costs.
Government or public-health procurement.

Revenue constraints

Revenue is limited by:

Narrow clinical demand.
Old generic pricing.
Clinical substitution.
Limited promotional differentiation.
Low treatment volume.
Inventory carrying costs.
Regulatory obligations that are large relative to sales.

Margin profile

Gross margin can be volatile. A small increase in sterile manufacturing cost, API cost, testing expense, or batch failure risk can materially reduce profitability. A supplier with an existing aseptic facility may achieve better economics than a new entrant because fixed manufacturing costs are already absorbed across a larger portfolio.

A low-volume injectable generic can remain commercially available even when annual revenue is modest if it supports a broader hospital portfolio or meets a strategic supply requirement. A standalone manufacturer may instead discontinue it if contribution margins fall below internal thresholds.

Which companies are challenging sulfadiazine sodium?

The competitive field is likely composed of generic and specialty pharmaceutical suppliers rather than branded innovators. Public company filings generally do not identify sulfadiazine sodium as a separate revenue line. Competitor analysis therefore requires product-level review of FDA approvals, National Drug Code records, wholesaler availability, tender data, and current label status.

The most relevant competitors may not sell an identical product. They can include:

Other sulfadiazine formulations.
Alternative sulfonamides.
Combination regimens for toxoplasmosis.
Hospital-compounded preparations.
Therapeutically suitable substitute antibiotics.

A supplier with a technically equivalent product can still have limited commercial access if it lacks hospital contracting, distribution coverage, or validated sterile capacity.

What licensing deals affect sulfadiazine sodium?

No major, publicly disclosed licensing transaction is generally associated with sulfadiazine sodium as a standalone commercial asset. That is consistent with its mature generic status.

Potential transaction structures would be commercial rather than innovation-led:

Contract manufacturing.
API supply agreements.
Authorized-generic distribution.
Regional marketing rights.
Hospital-tender partnerships.
Product acquisition from a discontinued-product portfolio.

The financial value of such a transaction would depend on approved manufacturing capacity, historical shortage performance, customer contracts, and regulatory status. It would not normally be based on patent duration or projected blockbuster growth.

What patent litigation and settlements affect sulfadiazine sodium?

No major active patent litigation or settlement-driven generic-entry event is expected to define the sulfadiazine sodium market. The product is outside the typical profile of high-value pharmaceutical litigation involving a branded reference product, multiple formulation patents, and a delayed generic launch.

Litigation risk is more likely to arise from:

Product-liability claims.
Manufacturing defects.
Sterility failures.
Regulatory enforcement.
Contract disputes.
Trademark or labeling issues.

These risks can affect a supplier’s financial results more directly than patent disputes.

What generic launch scenarios exist for sulfadiazine sodium?

Base case: stable niche supply

One or more suppliers maintain approval and supply. Prices remain generic, demand stays limited, and revenue changes little except for procurement cycles.

Shortage-driven upside

A competitor exits or experiences a manufacturing interruption. Remaining suppliers increase volume or pricing, producing temporary revenue and margin expansion.

Supply erosion

The remaining supplier faces API, quality, or sterile-capacity constraints. Hospitals move to alternatives, reducing demand even if the product remains clinically relevant.

New entrant scenario

A new supplier enters after identifying an unmet hospital need. The entrant must overcome low demand, validation costs, FDA compliance requirements, and incumbent contracting relationships. Entry is more likely after a shortage than during a stable, low-price market.

How does sulfadiazine sodium compare with silver sulfadiazine?

Attribute	Sulfadiazine sodium	Silver sulfadiazine
Primary use	Systemic antibacterial use and selected combination regimens	Topical burn and wound treatment
Administration	Oral or injectable, depending on product	Topical cream or related topical presentation
Market demand	Narrow systemic use	Broader institutional and outpatient topical use
Commercial scale	Small niche generic	Larger and more diversified topical market
Patent importance	Limited for the old molecule	Formulation and topical-product competition may matter more
Substitution	Clinical alternatives may exist	Alternative wound-care products and topical antimicrobials
Supply risk	High if injectable supply is concentrated	Usually more diversified by dosage form

Confusing the two products can lead to materially incorrect estimates of market size, revenue, and competitive intensity.

What is the commercial outlook for sulfadiazine sodium?

The outlook is defensive rather than growth-oriented. The product can retain strategic value because a small clinical market may still require dependable access, particularly for specialized infectious-disease treatment. Its revenue base is unlikely to expand materially without a shortage, a new approved presentation, or a procurement-driven change.

For investors, licensors, and generic manufacturers, the key diligence variables are:

Current FDA marketing status.
Number of active suppliers.
Injectable versus oral presentation.
Recent shortage history.
API source concentration.
Hospital contract renewal rates.
Product-level price and volume trends.
Manufacturing inspection history.
Discontinuation risk.
Availability of clinically acceptable substitutes.

A forecast based on broad sulfonamide market data would not be reliable for sulfadiazine sodium. Product-level sales data and current supplier records are required for a defensible valuation.

Key Takeaways

Sulfadiazine sodium is a mature, low-volume generic antimicrobial with limited growth potential.
Original molecular exclusivity is expired; current commercial protection comes from regulatory compliance, manufacturing capability, and supply reliability.
No major Paragraph IV or patent-litigation event is expected to drive the market.
Injectable manufacturing and sterile quality controls can create stronger practical barriers than patents.
Public sources do not provide a dependable standalone revenue figure.
Financial performance is most sensitive to supplier exits, shortages, hospital contracts, API costs, and manufacturing continuity.
Sulfadiazine sodium should not be analyzed using market data for silver sulfadiazine or broader sulfonamide categories.
The base case is stable niche demand, with temporary upside during supply disruption and downside risk from discontinuation or substitution.

FAQs

Is sulfadiazine sodium still commercially available?

Availability depends on the specific dosage form, sponsor, and jurisdiction. FDA approval, active-marketing status, wholesaler inventory, and shortage records should be reviewed separately.

Is sulfadiazine sodium a branded drug or a generic drug?

It is commercially treated as an established generic drug. Its value does not depend on new-drug exclusivity or a premium branded franchise.

Does sulfadiazine sodium have biosimilar competition?

No. Biosimilar regulation applies to biological products. Sulfadiazine sodium is a chemically synthesized small-molecule drug and faces generic, not biosimilar, competition.

Can sulfadiazine sodium prices increase despite being generic?

Yes. Low-volume sterile products can experience price increases when manufacturing costs rise, a supplier exits, or a shortage reduces competition. Such increases may be temporary.

Is sulfadiazine sodium attractive for pharmaceutical licensing?

It is more suitable for contract manufacturing, regional distribution, or hospital-supply transactions than for a patent-led licensing deal. Commercial value depends on approved capacity, supply reliability, and customer access.

References

U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: The Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/approved-drug-products-therapeutic-equivalence-evaluations-orange-book
U.S. Food and Drug Administration. (2024). Drug shortages. https://www.fda.gov/drugs/drug-safety-and-availability/drug-shortages
U.S. National Library of Medicine. (2024). DailyMed: Current drug labeling. https://dailymed.nlm.nih.gov/dailymed/
U.S. Food and Drug Administration. (2024). Abbreviated new drug application approvals. https://www.fda.gov/drugs/abbreviated-new-drug-application-anda
World Health Organization. (2023). WHO model list of essential medicines, 23rd list. https://www.who.int/publications/i/item/WHO-MHP-HPS-EML-2023.02

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	1
Drug Master File Entries:	2
Raw Ingredient (Bulk) Api Vendors:	58
Patent Applications:	346
DailyMed Link:	SULFADIAZINE SODIUM at DailyMed

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Lederle	SULFADIAZINE SODIUM	sulfadiazine sodium	INJECTABLE;INJECTION	004054-002	Approved Prior to Jan 1, 1982		DISCN	No	No	⤷ Start Trial	⤷ Start Trial				⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Exclusivity Expiration

Summary for SULFADIAZINE SODIUM

Anatomical Therapeutic Chemical (ATC) Classes for SULFADIAZINE SODIUM