IOTHALAMATE SODIUM - Generic Drug Details

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

Iothalamate sodium is the generic ingredient in four branded drugs marketed by Mallinckrodt and Isotex, and is included in four NDAs. Additional information is available in the individual branded drug profile pages.

Summary for IOTHALAMATE SODIUM

US Patents:	0
Tradenames:	4
Applicants:	2
NDAs:	4
Raw Ingredient (Bulk) Api Vendors:	19
Clinical Trials:	6
DailyMed Link:	IOTHALAMATE SODIUM at DailyMed

Recent Clinical Trials for IOTHALAMATE SODIUM

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

Sponsor	Phase
Mayo Clinic	Phase 2
National Heart, Lung, and Blood Institute (NHLBI)	Phase 1
Mayo Clinic	Phase 1

See all IOTHALAMATE SODIUM clinical trials

US Patents and Regulatory Information for IOTHALAMATE SODIUM

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Mallinckrodt	CONRAY 325	iothalamate sodium	INJECTABLE;INJECTION	017685-001	Approved Prior to Jan 1, 1982		DISCN	No	No
Isotex	GLOFIL-125	iothalamate sodium i-125	INJECTABLE;INJECTION	017279-001	Approved Prior to Jan 1, 1982		RX	No	No
Mallinckrodt	CONRAY 400	iothalamate sodium	INJECTABLE;INJECTION	014295-001	Approved Prior to Jan 1, 1982		DISCN	No	No
Mallinckrodt	ANGIO-CONRAY	iothalamate sodium	INJECTABLE;INJECTION	013319-001	Approved Prior to Jan 1, 1982		DISCN	No	No

Iothalamate Sodium Market Dynamics, Patent Status, Competition, and Financial Trajectory

Last updated: September 5, 2026

Iothalamate sodium is an older, high-osmolar iodinated contrast agent used in radiographic procedures. Its commercial market has contracted as hospitals and imaging centers shifted toward nonionic, low-osmolar agents such as iohexol, iopamidol, ioversol, and iodixanol. The product remains relevant in selected diagnostic applications, but its financial profile is a mature, low-growth generic market rather than an innovation-driven pharmaceutical franchise.

Product-level revenue for iothalamate sodium is not publicly reported. Commercial exposure is generally embedded in broader radiology-contrast portfolios, primarily through Conray products and institutional purchasing contracts. The main value drivers are supply continuity, manufacturing cost, regulatory maintenance, and hospital formulary status.

What is iothalamate sodium used for?

Iothalamate sodium is an iodinated radiopaque contrast medium. It increases X-ray attenuation and is administered for selected angiographic, urographic, and computed tomography procedures.

Its principal commercial characteristics are:

Attribute	Iothalamate sodium
Therapeutic category	Diagnostic radiopharmaceutical and X-ray contrast agent
Chemical class	Ionic, high-osmolar iodinated contrast medium
Primary use	X-ray, angiography, urography, and selected CT procedures
Delivery	Injectable solution
Typical commercial association	Conray product family
Regulatory pathway	Legacy FDA-approved drug product
Patent position	Mature, effectively off-patent
Biosimilar exposure	None
Main competitive threat	Nonionic low-osmolar contrast media

Iothalamate sodium is distinct from iothalamate meglumine, although both salts have been used in related contrast products. Product selection depends on iodine concentration, route of administration, procedure type, institutional protocol, and physician preference.

What products contain iothalamate sodium?

The main commercial association is the Conray franchise, historically developed and marketed through the Liebel-Flarsheim radiology business and later associated with Guerbet. Conray products include different iothalamate formulations and iodine concentrations, so the presence of iothalamate sodium must be determined from the specific product label rather than the brand name alone.

What is the FDA regulatory status of iothalamate sodium?

The FDA has approved iothalamate-based injectable contrast products for diagnostic imaging indications. FDA labeling identifies the approved routes, concentrations, contraindications, warnings, and adverse reactions for each product. Products may be marketed under legacy new drug applications, supplemental approvals, or successor commercial arrangements. [1]

Regulatory risk is concentrated in manufacturing and quality compliance rather than clinical development. Key requirements include:

• Sterility assurance for injectable products.
• Control of iodine concentration and solution composition.
• Stability through the labeled shelf life.
• Container-closure integrity.
• Control of particulate matter and pyrogens.
• Compliance with current good manufacturing practice requirements.
• Ongoing adverse-event reporting and label maintenance.

Because iothalamate sodium is an established contrast agent, a new entrant would generally face a lower clinical-development burden than a novel diagnostic drug. The commercial challenge is reliable production at competitive cost.

What is the Orange Book status of iothalamate sodium?

Iothalamate sodium has the profile of a legacy, off-patent drug rather than a product protected by active composition-of-matter exclusivity. No commercially meaningful exclusivity period is expected to remain for the underlying active ingredient.

The FDA Orange Book is relevant for determining:

• Whether a specific reference-listed drug remains active.
• Whether an NDA is listed as discontinued or withdrawn.
• Whether patents or regulatory exclusivities are associated with a product.
• Whether an abbreviated new drug application may reference an approved product.

For legacy iothalamate products, the commercial barrier is generally not patent enforcement. It is the ability to obtain or maintain approval, qualify a manufacturing site, meet injectable-drug quality requirements, and secure hospital contracts. [2]

When does iothalamate sodium lose exclusivity?

The active ingredient lost meaningful exclusivity decades ago. Iothalamate is an older contrast agent introduced before the modern patent and regulatory environment that applies to new molecular entities. Any remaining commercial rights are more likely to involve:

• Product-specific formulation know-how.
• Manufacturing processes.
• Packaging and presentation.
• Trademarks such as Conray.
• Distribution agreements.
• Customer contracts.
• Site-specific regulatory approvals.

These rights do not create the same barrier as a valid composition patent or market exclusivity period.

How many patents cover iothalamate sodium?

No active composition-of-matter patent is expected to protect iothalamate sodium as a commercial product. Any historical patents covering the molecule, synthesis, formulation, or use would generally have expired.

The relevant distinction is between patent protection and operational protection:

Protection type	Current commercial relevance
Active-ingredient patent	Low or none
Composition-of-matter patent	Expired
Method-of-use patent	Limited for established diagnostic indications
Formulation patent	Possible historically, but unlikely to block ordinary generic entry
Manufacturing process patent	Potentially relevant if narrow and unexpired
Trademark protection	Relevant to branding, not market exclusivity
Regulatory approval	Required for lawful commercialization
Supply-chain qualification	Important practical barrier

What formulations are protected by iothalamate sodium patents?

The commercially relevant product is an injectable aqueous contrast solution containing an iothalamate salt at a specified iodine concentration. Historical formulation claims may have addressed concentration, salt selection, excipients, pH, stability, packaging, or sterilization.

Those formulation concepts are unlikely to create a material current barrier unless a specific unexpired patent covers a narrowly defined commercial formulation. In practice, a competing manufacturer could avoid a legacy formulation claim by using a different concentration, excipient profile, container system, or manufacturing process while preserving the same diagnostic function.

Are there Paragraph IV challenges for iothalamate sodium?

Paragraph IV litigation is not expected to be a major current issue for iothalamate sodium. Paragraph IV certifications apply when an ANDA applicant challenges a listed patent for a reference product. Because iothalamate sodium is a mature contrast agent with no apparent commercially important patent estate, the principal entry path is more likely to involve ordinary abbreviated approval or a product-specific regulatory strategy rather than high-value patent litigation.

Potential litigation would be more likely to concern:

• The scope of an Orange Book-listed patent, if one exists for a particular product.
• FDA approval status of a reference product.
• Manufacturing or quality defects.
• Distribution rights.
• Trademark or unfair-competition claims.
• Product-liability disputes.

No major, current Paragraph IV campaign is associated with iothalamate sodium in the public commercial profile of the product.

What patent litigation affects iothalamate sodium?

Iothalamate sodium does not have the litigation profile of branded oncology, immunology, or cardiometabolic drugs. There is no recognized current patent dispute that materially determines market access for the active ingredient.

The absence of high-value patent litigation shifts competitive analysis toward operational factors:

1. Whether the manufacturer has an approved injectable facility.
2. Whether the product can be supplied consistently.
3. Whether the manufacturer can meet hospital tender pricing.
4. Whether the formulation is compatible with existing imaging protocols.
5. Whether the product has a reliable shortage-management record.

For contrast media, a manufacturing interruption can have greater short-term commercial impact than a patent dispute. Hospitals may retain incumbent suppliers because switching contrast agents can affect procurement, protocols, inventory, and staff familiarity.

How does iothalamate sodium compare with newer contrast agents?

Iothalamate sodium competes mainly on price and availability. Nonionic low-osmolar agents compete on tolerability, clinical familiarity, protocol integration, and institutional standardization.

Factor	Iothalamate sodium	Iohexol, iopamidol, ioversol, and iodixanol
Ionicity	Ionic	Primarily nonionic
Osmolality	High relative to modern low-osmolar products	Low or iso-osmolar
Historical role	Established contrast agent	Current mainstream hospital products
Cost position	Potentially favorable	Higher in some purchasing settings
Clinical preference	More limited	Broad institutional adoption
Patent status	Mature and off-patent	Some products also mature; selected formulation and use rights may vary
Market growth	Flat to declining	More resilient due to current protocol use
Differentiation	Price and supply	Tolerability, workflow, concentration, and contracts

The move from ionic high-osmolar agents to nonionic low-osmolar media was driven by concerns about adverse reactions and tolerability. This structural shift limits the ability of iothalamate sodium to regain broad market share without a major price advantage or supply disruption affecting competing products.

What is the financial trajectory for iothalamate sodium?

The financial trajectory is best characterized as mature, declining, and low visibility at the individual-product level.

Revenue exposure

Manufacturers generally report sales by business segment, geography, or contrast-media portfolio. They do not typically disclose revenue, gross margin, or unit volume for iothalamate sodium separately. Guerbet, for example, reports broader pharmaceutical imaging and contrast-media activities rather than a standalone iothalamate sodium revenue line. [3]

The product’s revenue profile likely has four features:

• Low unit-price growth.
• Declining or stable procedure share.
• Limited promotional spending.
• Margin dependence on manufacturing efficiency and procurement contracts.

Market dynamics

Demand is supported by the installed base of imaging procedures and the continued need for iodinated contrast. Demand is constrained by substitution toward low-osmolar nonionic agents, hospital protocol changes, and product rationalization.

The addressable market is therefore maintenance-driven. Volume can remain stable in specific geographies or institutions, but long-term growth is unlikely without a supply shortage among competing agents or a sharp price advantage.

Margin outlook

Margins depend on:

• Active pharmaceutical ingredient and iodine-related input costs.
• Sterile manufacturing utilization.
• Batch size and production scale.
• Packaging costs.
• Freight and temperature-control requirements.
• Hospital tender discounts.
• Product recalls or manufacturing remediation.
• Regulatory costs for legacy facilities.

A legacy injectable may have attractive gross margins when produced at scale, but low volumes can raise unit costs and make continued commercialization uneconomic. This creates a risk of market withdrawal even when clinical demand remains.

Which companies are challenging iothalamate sodium?

Competition is less concentrated around direct iothalamate sodium substitutes than around the broader iodinated contrast market.

Relevant competitive groups include:

• Guerbet and its contrast-media portfolio.
• GE HealthCare, particularly through iohexol and related imaging agents.
• Bracco, including iopamidol-based products.
• Bayer, including iodixanol-related contrast products in relevant markets.
• Generic or regional manufacturers of injectable iodinated contrast media.
• Contract manufacturers and specialty pharmaceutical suppliers.

The principal challenge is therapeutic substitution, not direct branded competition. Hospitals can replace iothalamate sodium with another iodinated contrast agent when clinical protocols, procurement rules, and product availability permit.

What generic entry risks exist for iothalamate sodium?

Generic entry risk is already largely realized because the active ingredient is mature and patent barriers are limited. The remaining risk to an incumbent is not a single patent cliff. It is incremental share loss from:

• Lower-priced injectable competitors.
• Hospital group purchasing organization tenders.
• Private-label or regional supply.
• Product discontinuation by incumbent suppliers.
• Contract rebidding.
• Substitution by nonionic contrast media.
• Regulatory approval of alternative concentrations or presentations.

A new entrant still faces meaningful technical barriers. Sterile injectable manufacturing is more difficult than ordinary solid-dose generic production, and contrast agents require reliable control of iodine concentration, osmolality, sterility, impurities, and packaging.

What licensing deals affect iothalamate sodium?

No major recent licensing transaction is known to have created a new exclusivity position for iothalamate sodium. The commercial history has been shaped more by portfolio ownership, product-line transfers, manufacturing arrangements, and distribution relationships than by novel drug licensing.

Any licensing value is likely to involve:

• Regional commercialization rights.
• Manufacturing and supply agreements.
• Portfolio acquisitions.
• Distribution rights for radiology products.
• Transfer of regulatory approvals.

These arrangements can preserve market access but do not materially extend exclusivity for the active ingredient.

What is the generic launch scenario for iothalamate sodium?

A generic launch would likely be commercially viable only under specific conditions:

Launch factor	Assessment
Patent barrier	Low
Clinical-development burden	Low relative to new drugs
Sterile manufacturing burden	High
Hospital switching barrier	Moderate
Price competition	High
Revenue ceiling	Limited
Supply-contract importance	High
Long-term growth	Low

A successful entrant would need an approved facility, dependable supply, competitive pricing, and access to hospital procurement channels. The product could generate recurring revenue in a niche market, but it is unlikely to support a large standalone franchise.

What geographic markets matter for iothalamate sodium?

The commercial outlook differs by geography. North American markets place greater emphasis on nonionic low-osmolar contrast media, formulary standardization, and group purchasing. Emerging markets may retain greater use of older ionic agents where acquisition cost is a stronger purchasing factor.

Geographic performance depends on:

• Local regulatory approval.
• Reimbursement and tender structures.
• Availability of competing contrast media.
• Hospital purchasing policies.
• Import and export controls.
• Local sterile manufacturing capacity.
• Clinical preference and national imaging guidelines.

The same product may remain commercially sustainable in a price-sensitive market while declining in higher-income markets with stronger adoption of low-osmolar agents.

Key Takeaways

• Iothalamate sodium is a mature ionic, high-osmolar iodinated contrast agent.
• The active ingredient is effectively off-patent, with no meaningful composition-of-matter exclusivity expected.
• Orange Book and Paragraph IV issues are secondary to manufacturing, regulatory, and procurement factors.
• Product-level revenue is not publicly disclosed; sales are embedded in broader contrast-media portfolios.
• Market share is pressured by iohexol, iopamidol, ioversol, iodixanol, and other nonionic low-osmolar agents.
• Financial performance is likely flat to declining, with profitability driven by manufacturing scale and hospital contracts.
• Generic entry is technically feasible but constrained by sterile injectable production and limited market size.
• No biosimilar risk applies because iothalamate sodium is a small-molecule diagnostic agent.
• The strongest commercial risks are substitution, price compression, supply interruption, and product discontinuation.

FAQs About Iothalamate Sodium

Is iothalamate sodium still commercially available?

Iothalamate-based contrast products remain associated with legacy radiology portfolios, but availability depends on the specific product, market, manufacturer, and current regulatory status.

Is iothalamate sodium a high-osmolar contrast agent?

Yes. Iothalamate sodium belongs to the older ionic, high-osmolar class of iodinated contrast media.

Does iothalamate sodium have biosimilar competition?

No. Biosimilar rules apply to biologic products. Iothalamate sodium is a small-molecule drug and is subject to generic-drug principles.

What is the main substitute for iothalamate sodium?

The main substitutes are nonionic low-osmolar iodinated contrast agents, including iohexol, iopamidol, ioversol, and iodixanol.

Can a manufacturer still obtain FDA approval for a generic iothalamate sodium product?

A manufacturer could pursue an abbreviated or other applicable FDA approval pathway, but commercial success would depend on sterile manufacturing capability, product equivalence, regulatory compliance, pricing, and hospital procurement access.

References

1. U.S. Food and Drug Administration. (n.d.). Iothalamate meglumine and iothalamate sodium injection prescribing information. FDA.

2. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations. FDA.

3. Guerbet. (2024). Universal registration document and annual financial report. Guerbet.