UREA, C-14 - Generic Drug Details

What are the generic sources for urea, c-14 and what is the scope of freedom to operate?

Urea, c-14 is the generic ingredient in two branded drugs marketed by Avent and is included in one NDA. Additional information is available in the individual branded drug profile pages.

Summary for UREA, C-14

US Patents:	0
Tradenames:	2
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	11
What excipients (inactive ingredients) are in UREA, C-14?	UREA, C-14 excipients list
DailyMed Link:	UREA, C-14 at DailyMed

US Patents and Regulatory Information for UREA, C-14

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Avent	PYTEST KIT	urea, c-14	CAPSULE;ORAL	020617-002	May 9, 1997		DISCN	Yes	No
Avent	PYTEST	urea, c-14	CAPSULE;ORAL	020617-001	May 9, 1997		DISCN	Yes	No

Expired US Patents for UREA, C-14

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Avent	PYTEST	urea, c-14	CAPSULE;ORAL	020617-001	May 9, 1997	4,830,010
Avent	PYTEST KIT	urea, c-14	CAPSULE;ORAL	020617-002	May 9, 1997	4,830,010

Urea C-14 Market Dynamics, Patent Position, FDA Status, and Financial Trajectory

Last updated: September 9, 2026

Urea C-14 is a diagnostic radiopharmaceutical used in carbon-14 urea breath tests for detecting active Helicobacter pylori infection. It is not a conventional therapeutic drug and has limited standalone financial disclosure. Its commercial value comes from recurring diagnostic testing, not from a large branded-drug revenue model. The market faces structural pressure from nonradioactive carbon-13 urea breath tests, stool-antigen testing, molecular assays, and endoscopic diagnostics.

What is Urea C-14 used for?

Urea C-14 is an orally administered, radiolabeled form of urea. During a breath test, H. pylori urease breaks down the compound and generates labeled carbon dioxide. The patient’s breath is then analyzed for the isotope.

The product is used for:

• Initial detection of active H. pylori infection
• Confirmation that eradication therapy succeeded
• Assessment of recurrent infection
• Noninvasive testing when endoscopy is not indicated

The test detects active infection, unlike serology, which can remain positive after eradication. The American College of Gastroenterology recommends test-of-cure testing after treatment, generally with a urea breath test or stool-antigen test, after the appropriate medication washout period (Chey et al., 2024).

Urea C-14 products are diagnostic agents. Their market is therefore governed by laboratory utilization, physician testing patterns, payer coverage, radiation-handling requirements, and the prevalence of H. pylori, rather than by treatment duration or chronic prescription volume.

What is the FDA regulatory status of Urea C-14?

Urea C-14 breath-test products have been regulated in the United States as prescription diagnostic products. Product-specific regulatory status depends on the manufacturer, formulation, and marketing authorization.

The principal U.S. product historically associated with carbon-14 urea breath testing is PYtest, a radiolabeled urea diagnostic capsule. The product is used with a breath-collection and analysis procedure rather than as an independent therapeutic agent.

Key regulatory characteristics include:

Regulatory issue	Urea C-14 position
Product category	Diagnostic radiopharmaceutical
Clinical purpose	Detection of active H. pylori infection
Administration	Oral capsule or dose followed by breath collection
Prescription status	Prescription diagnostic use
FDA pathway	Drug approval for radiolabeled urea diagnostic use, with product-specific labeling
Safety oversight	FDA drug regulation plus radiation-safety controls
Therapeutic indication	None
Primary alternatives	Carbon-13 urea breath tests, stool-antigen tests, endoscopy, molecular assays

Radiation exposure from a C-14 urea breath test is low, but it creates handling and patient-selection considerations that do not apply to carbon-13 testing. Pregnancy and pediatric use require particular attention to product labeling and clinical judgment.

The FDA Orange Book should be reviewed by product name and NDA to confirm current marketing status, approved labeling, patent listings, and any listed exclusivity. A general ingredient search for “urea C-14” may not capture all relevant product records because regulatory entries can be organized around a proprietary product name or sponsor-held NDA (U.S. Food and Drug Administration, n.d.-a).

What patents protect Urea C-14 products?

The core chemistry of carbon-14-labeled urea is old and is unlikely to support a meaningful current composition-of-matter patent position. Any remaining protection is more likely to relate to:

• Capsule or dosage-form design
• Breath-collection systems
• Analyzer technology
• Test timing and sample-processing methods
• Kit architecture
• Packaging and radioactive-material handling
• Specific diagnostic workflows
• Combination use with eradication-treatment monitoring

For a mature diagnostic such as Urea C-14, patent value generally shifts from the labeled molecule to the complete testing system. A patent covering a specific breath analyzer or assay workflow may protect a commercial platform even when the active diagnostic compound is no longer patent-protected.

No reliable current patent-expiration date can be assigned to “Urea C-14” as a generic ingredient without identifying the relevant product, sponsor, jurisdiction, and patent family. The active patent estate, if any, must be assessed at the product and assignee level through FDA Orange Book records, USPTO Patent Center, WIPO PATENTSCOPE, and national patent registers.

Are there formulation patents for Urea C-14?

Potential formulation protection is more commercially relevant than molecule-level protection. A formulation patent could cover:

• A stable C-14 urea capsule
• A defined radioactive dose
• Excipient selection
• Capsule dissolution or release characteristics
• Packaging that limits contamination or handling risk
• A kit containing the capsule, breath bags, and testing materials

Such claims are difficult to enforce broadly if competing suppliers use materially different packaging, dose presentation, or test workflows. The commercial barrier may therefore be regulatory validation and distribution capability rather than patent exclusion.

Are there method-of-use patents for carbon-14 urea breath testing?

Method-of-use patents may cover specific diagnostic protocols, including sample timing, pretest preparation, analysis thresholds, or use in a defined patient population. Their value is constrained by the need to avoid blocking established medical practice and by the availability of alternative test methods.

A method patent may have limited market impact if physicians can use carbon-13 breath testing, stool antigen, or endoscopy without practicing the claimed method.

When does Urea C-14 lose exclusivity?

Urea C-14 does not have a single universal exclusivity-loss date. Exclusivity depends on the specific marketed product and jurisdiction.

For a U.S. product, relevant dates may include:

Exclusivity category	Commercial significance
New chemical entity exclusivity	Unlikely to be relevant to a mature radiolabeled diagnostic
Three-year clinical-investigation exclusivity	Could apply to certain approved changes, if granted
Orphan exclusivity	Generally not expected for broad H. pylori diagnosis
Patent exclusivity	Depends on active listed patents
Regulatory exclusivity	May attach to a specific approval or supplement
Trade-secret protection	May cover manufacturing, calibration, or operating procedures

Even after patent expiration, a new competitor may need product-specific regulatory approval, manufacturing controls, radioactive-material licenses, validated analytical equipment, and an established distribution channel.

This distinction matters. Patent expiry can remove legal exclusivity without creating immediate generic competition. In low-volume diagnostic markets, the cost of regulatory maintenance and specialized distribution can discourage entry.

How strong is the patent estate for Urea C-14?

The patent estate appears structurally weaker than the estates surrounding innovative therapeutics or proprietary biologics.

Strengths

• Potential protection around integrated testing systems
• Specialized manufacturing and radiochemical controls
• Regulatory familiarity with established products
• Distribution relationships with gastroenterology practices and laboratories
• Switching costs where laboratories already own compatible analyzers

Weaknesses

• Old and readily understood active ingredient
• Multiple noninfringing diagnostic alternatives
• Limited ability to claim broad diagnostic concepts
• Low technical complexity in the underlying urease reaction
• Potential substitution by carbon-13 products
• Declining importance of molecule-level patent rights

The strongest commercial moat is likely operational rather than patent-based. It consists of manufacturing reliability, radioactive-material compliance, analyzer compatibility, reimbursement access, and physician familiarity.

Which companies compete with Urea C-14?

Competition is divided into direct and indirect segments.

Direct carbon-14 competitors

Direct competitors include suppliers of carbon-14 urea capsules, breath-test kits, and associated analyzers. The market is fragmented by geography, with product availability depending on national regulatory approvals and local radiation controls.

Carbon-13 urea breath tests

Carbon-13 is the principal technological substitute. It is nonradioactive and can be used in broader patient populations, including settings where radiation exposure is undesirable. Carbon-13 testing generally requires isotope-ratio or infrared analysis equipment, creating equipment and laboratory costs but avoiding radioactive-material controls.

Stool-antigen testing

Stool-antigen assays are widely used for both initial diagnosis and test-of-cure. They can be less expensive and easier to deploy outside specialized testing centers. Their performance depends on assay quality, medication washout, specimen handling, and laboratory practice.

Endoscopic and molecular testing

Endoscopic biopsy-based testing remains relevant when patients require upper gastrointestinal evaluation for other clinical reasons. Molecular assays can provide resistance information, particularly clarithromycin-resistance data, which is increasingly important as treatment selection becomes more complex.

Diagnostic approach	Main advantage	Main commercial pressure on Urea C-14
C-14 urea breath test	Established active-infection test	Radiation and specialized handling
C-13 urea breath test	Nonradioactive and broadly acceptable	Equipment cost and isotope supply
Stool antigen	Lower infrastructure requirement	Specimen logistics and medication interference
Endoscopic biopsy	Allows structural evaluation and testing	Invasive and higher procedure cost
Molecular assay	Can identify resistance markers	Higher assay complexity and cost

What market dynamics affect Urea C-14 demand?

Demand is driven by the number of patients tested for H. pylori, the proportion receiving test-of-cure testing, and the availability of local testing infrastructure.

Demand supports

• High global prevalence of H. pylori
• Greater adherence to post-treatment confirmation
• Rising concern about antibiotic resistance
• Clinical preference for tests that measure active infection
• Expansion of outpatient gastroenterology testing
• Continued use in markets with established C-14 infrastructure

Demand constraints

• Replacement by carbon-13 testing
• Use of stool-antigen assays
• Concerns about radiation exposure
• Restrictions affecting children and pregnant patients
• Limited availability of breath analyzers
• Low testing reimbursement in some markets
• Product supply interruptions caused by radiopharmaceutical logistics

The market is also sensitive to treatment guidelines. More frequent test-of-cure recommendations can increase test volumes, but clinicians may choose stool antigen or carbon-13 rather than C-14.

What is the financial trajectory for Urea C-14?

Urea C-14 has the financial profile of a mature, specialized diagnostic rather than a growth pharmaceutical.

Public companies generally do not report revenue for C-14 urea as a separate line item. Revenue is typically combined with broader diagnostic, radiopharmaceutical, gastrointestinal testing, or laboratory-product categories. As a result, product-level sales, gross margin, and operating-profit data are not consistently available in public filings.

The likely financial trajectory is:

1. Stable or modestly declining unit demand in developed markets where carbon-13 and stool-antigen testing are established.
2. Selective growth in regions expanding H. pylori diagnosis and treatment monitoring.
3. Margin pressure from low-cost diagnostic alternatives.
4. Continued value from installed equipment and recurring consumable use.
5. Potential supply-driven price increases in markets with few approved suppliers.
6. Limited upside from molecule innovation because the underlying chemistry is mature.

The product can remain profitable if manufacturing costs are low, regulatory overhead is controlled, and the supplier has recurring access to gastroenterology practices, hospitals, and diagnostic laboratories. The addressable market is unlikely to support the revenue scale or pricing power associated with branded therapeutics.

Revenue exposure by business model

Business model	Revenue outlook
Capsule-only supplier	Vulnerable to price competition and substitution
Integrated kit supplier	More defensible through workflow convenience
Analyzer plus consumables	Recurring revenue and higher switching costs
Hospital-based radiopharmacy	Dependent on local testing volume
Global diagnostic platform	Can offset C-14 decline with carbon-13 or molecular products

What generic launch risks exist for Urea C-14?

Generic entry risk is moderate at the molecule level but lower at the complete-system level.

A competitor could potentially reproduce the labeled urea product after relevant patent and regulatory barriers expire. Entry would still require:

• Reliable carbon-14 radiochemistry
• GMP manufacturing
• Dose and stability validation
• Radioactive-material licensing
• Approved labeling
• Breath-analysis compatibility
• Distribution and waste-handling procedures
• Commercial reimbursement support

The most credible competitive threat is not necessarily a generic C-14 capsule. It is substitution by a nonradioactive or non-breath-based test. This makes market-share erosion more important than classic generic price erosion.

What patent litigation and settlement agreements affect Urea C-14?

There is no broadly recognized, high-value patent litigation trend comparable to litigation involving blockbuster small molecules, biologics, or major drug-delivery platforms. The absence of major public litigation is consistent with a mature diagnostic market in which the core compound has limited exclusivity value.

Any relevant dispute would more likely involve:

• Analyzer compatibility
• Diagnostic threshold methodology
• Kit architecture
• Manufacturing processes
• Trade secrets
• Regulatory approval rights
• Distribution or licensing arrangements

Publicly documented licensing and settlement economics for Urea C-14 are limited. Product-level licensing arrangements may be embedded in private manufacturing, distribution, or technology-transfer contracts rather than reported separately.

How does Urea C-14 compare with carbon-13 urea testing?

Factor	Urea C-14	Urea C-13
Radiation	Uses radioactive isotope	Nonradioactive
Patient restrictions	Greater concern in pregnancy and some pediatric settings	Broader clinical acceptability
Infrastructure	Radioactive handling and specialized testing	Isotope-ratio or infrared analyzer
Market position	Mature and established in selected markets	Stronger long-term substitution profile
Patent value	Mostly system and workflow claims	Similar system-level protection
Financial outlook	Stable to declining in developed markets	Better growth potential
Main barrier	Radiation compliance	Analyzer and isotope cost

What geographic markets have the strongest opportunity?

C-14 urea breath testing is most defensible where:

• Carbon-13 analyzers are not widely installed
• Stool-antigen testing has limited uptake
• Local clinicians prefer breath testing
• Radiopharmaceutical distribution is reliable
• H. pylori prevalence is high
• Reimbursement supports noninvasive testing

The United States and Western Europe have stronger substitution pressure from carbon-13, stool antigen, and molecular methods. Emerging markets may offer volume growth, but pricing, regulatory registration, supply-chain reliability, and reimbursement can limit profitability.

Key Takeaways

• Urea C-14 is a diagnostic radiopharmaceutical, not a therapeutic drug.
• Its primary use is noninvasive detection and confirmation of active H. pylori infection.
• The core labeled molecule has limited current patent value.
• Any meaningful patent protection is more likely to cover formulations, kits, analyzers, or diagnostic workflows.
• No single expiration date applies to Urea C-14 across products or jurisdictions.
• Carbon-13 urea testing is the principal technological substitute.
• Stool-antigen testing creates additional price and volume pressure.
• Product-level revenue is generally not disclosed separately by public companies.
• The financial profile is mature, specialized, and likely stable to declining in developed markets.
• Manufacturing, regulatory compliance, distribution, and installed testing infrastructure are more important barriers than composition-of-matter patents.
• The principal launch risk is diagnostic substitution rather than a conventional generic-price collapse.

FAQs

Is Urea C-14 a radioactive drug?

Yes. Urea C-14 contains carbon-14 and is used as a radioactive diagnostic agent in a breath test for H. pylori. It is not used to treat the infection.

Is Urea C-14 still commercially relevant?

Yes, but its relevance is concentrated in markets and laboratories that already support carbon-14 breath testing. Carbon-13 testing and stool-antigen assays limit long-term growth.

Can a generic company manufacture Urea C-14?

Potentially, but entry requires more than reproducing the labeled compound. Regulatory approval, radioactive-material controls, GMP production, assay validation, and distribution capability are necessary.

Does Urea C-14 have Orange Book patents?

Any Orange Book listing must be confirmed against the specific branded product and NDA. The generic ingredient name alone is not sufficient to establish current patent listings or expiration dates.

What is the largest commercial risk for Urea C-14?

The largest risk is substitution by carbon-13 urea breath tests and stool-antigen assays, not necessarily direct infringement litigation or generic competition.

References

American College of Gastroenterology. (2024). ACG clinical guideline: Treatment of Helicobacter pylori infection. The American Journal of Gastroenterology.

U.S. Food and Drug Administration. (n.d.-a). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.accessdata.fda.gov/scripts/cder/ob/

U.S. Food and Drug Administration. (n.d.-b). Drugs@FDA: FDA-approved drugs. https://www.accessdata.fda.gov/scripts/cder/daf/

U.S. Food and Drug Administration. (n.d.-c). Labeling and regulatory information for radiopharmaceuticals. https://www.fda.gov/drugs

World Health Organization. (2023). WHO updates list of drug-resistant bacteria most threatening to human health. https://www.who.int/news/item/17-05-2024-who-updates-list-of-drug-resistant-bacteria-most-threatening-to-human-health