PEDIAZOLE Drug Patent Profile

When do Pediazole patents expire, and when can generic versions of Pediazole launch?

Pediazole is a drug marketed by Ross Labs and is included in one NDA.

The generic ingredient in PEDIAZOLE is erythromycin ethylsuccinate; sulfisoxazole acetyl. There is one drug master file entry for this compound. Additional details are available on the erythromycin ethylsuccinate; sulfisoxazole acetyl profile page.

Summary for PEDIAZOLE

US Patents:	0
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	3
Patent Applications:	19
DailyMed Link:	PEDIAZOLE at DailyMed

US Patents and Regulatory Information for PEDIAZOLE

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Ross Labs	PEDIAZOLE	erythromycin ethylsuccinate; sulfisoxazole acetyl	GRANULE;ORAL	050529-001	Approved Prior to Jan 1, 1982		DISCN	No	No

Pediazole Market Dynamics, FDA Status, Patent Position, and Financial Trajectory

Last updated: September 5, 2026

Pediazole is the former brand name for an oral pediatric antibiotic combining erythromycin ethylsuccinate and sulfisoxazole acetyl. Its commercial value has declined sharply as acute otitis media treatment shifted toward amoxicillin and amoxicillin-clavulanate, while combination antibiotic use and sulfonamide exposure became less attractive. Pediazole has no meaningful current patent-based pricing power, no biosimilar exposure, and no identifiable standalone revenue stream in public company filings.

What is Pediazole and what was it used for?

Pediazole contained two antibacterial ingredients:

Attribute	Pediazole profile
Active ingredients	Erythromycin ethylsuccinate and sulfisoxazole acetyl
Dosage form	Oral suspension after reconstitution
Therapeutic area	Pediatric bacterial infections, especially otitis media
Drug class	Macrolide plus sulfonamide combination
Regulatory pathway	Historical FDA prescription drug approval
Current commercial status	Limited or discontinued market availability
Biosimilar relevance	None
Primary competitive alternatives	Amoxicillin, amoxicillin-clavulanate, cefdinir, azithromycin

The product was designed to provide coverage against common pediatric pathogens when clinicians wanted a macrolide-sulfonamide combination. Its clinical position weakened as treatment guidelines favored narrower, better-established therapies. The American Academy of Pediatrics recommends high-dose amoxicillin as first-line treatment for most children with acute otitis media, with amoxicillin-clavulanate used in selected circumstances.[1]

What is the FDA regulatory status of Pediazole?

Pediazole is a historical FDA-approved product rather than a growth-stage pharmaceutical asset. Public FDA labeling and drug databases identify the product as an erythromycin ethylsuccinate and sulfisoxazole acetyl oral suspension.[2]

The FDA’s discontinued-drug framework distinguishes commercial discontinuation from withdrawal for safety or efficacy reasons. A product can disappear from the market because of manufacturing, commercial, supply-chain, or demand conditions without the FDA determining that it was unsafe or ineffective.[3]

The practical regulatory assessment is:

Regulatory issue	Assessment
Current branded commercial opportunity	Minimal
FDA pediatric demand	Reduced by treatment substitution
FDA exclusivity	Expired or no longer commercially material
Current shortage relevance	No major current market role identified
Withdrawal-for-safety conclusion	Cannot be inferred merely from discontinuation
Regulatory re-entry barrier	Manufacturing validation, quality compliance, and commercial scale

The label’s historical indications do not create a durable market advantage. Pediatric antibiotic prescribing has moved toward guideline-supported monotherapies, limiting the commercial relevance of the older combination.

When did Pediazole lose market exclusivity?

Pediazole’s original regulatory and patent exclusivity periods are long expired. The product dates from an earlier generation of antibiotic products, and any ordinary small-molecule patent protection would have ended decades ago.

No commercially meaningful patent exclusivity appears to protect the historical Pediazole product today. A current Orange Book review is the controlling source for listed patents and regulatory exclusivity.[4] The product’s age and generic composition indicate that market access is constrained by economics and manufacturing capability, not by an active composition-of-matter patent.

Pediazole patent position

Patent category	Current commercial significance
Composition-of-matter patent	Expired
Formulation patent	No known active protection with meaningful market effect
Method-of-use patent	No known active protection controlling pediatric antibiotic use
Pediatric exclusivity	Expired
Orphan exclusivity	Not applicable
Regulatory exclusivity	Expired
Orange Book litigation exposure	No material current exposure identified

The absence of active exclusivity means a qualified manufacturer could theoretically commercialize an equivalent product through the applicable abbreviated or supplemental FDA pathway, subject to product-specific regulatory requirements. That opportunity is limited by low demand and the availability of cheaper substitutes.

How many patents cover Pediazole?

Pediazole has no commercially relevant active patent estate based on its historical product profile and age. The relevant intellectual-property barriers are operational rather than legal.

Potential barriers include:

• Recreating the original suspension chemistry.
• Demonstrating stability throughout the labeled shelf life.
• Controlling taste, sedimentation, and redispersibility.
• Validating microbial limits for a pediatric liquid product.
• Establishing current manufacturing and packaging controls.
• Maintaining supply of both active ingredients.
• Supporting pediatric labeling and post-market compliance.

A manufacturer would not need to overcome an active branded patent moat comparable to those surrounding newer antibiotics or specialty drugs. The challenge would be whether the expected volume justifies development, validation, registration, and ongoing pharmacovigilance costs.

What formulations are protected by Pediazole patents?

The historical Pediazole formulation was an oral suspension containing erythromycin ethylsuccinate and sulfisoxazole acetyl. Any formulation-specific protection associated with the original product is expired or commercially irrelevant.

The technical value of the formulation was not a durable patent barrier. It was the ability to produce a palatable and stable pediatric liquid containing two chemically distinct antibiotics. That formulation may still create development complexity, but complexity alone does not provide exclusivity.

A modern entrant would likely evaluate:

1. Powder-for-reconstitution manufacturing.
2. Flavoring and taste-masking systems.
3. Particle-size distribution.
4. Suspension uniformity.
5. Reconstitution instructions and dosing accuracy.
6. Stability after reconstitution.
7. Container-closure compatibility.

These attributes can affect product quality and patient acceptance, but they would not normally prevent a competent generic manufacturer from developing an equivalent product.

What drove the decline in Pediazole demand?

Pediazole’s decline reflects therapeutic substitution, antibiotic stewardship, and unfavorable product economics.

Shift to amoxicillin-based treatment

Amoxicillin became the principal first-line treatment for uncomplicated acute otitis media. It is inexpensive, widely available, familiar to pediatric clinicians, and easier to manufacture as a single-agent suspension.

Amoxicillin-clavulanate captures patients requiring broader beta-lactamase coverage. Oral cephalosporins and azithromycin provide alternatives for selected patients with penicillin allergy.

Combination-product disadvantage

Pediazole combines two antibiotics where many clinical situations can be treated with one. Combination products can carry higher manufacturing complexity, more adverse-effect concerns, and less favorable stewardship profiles.

Sulfonamide-related constraints

Sulfisoxazole is an older sulfonamide. Sulfonamide hypersensitivity, tolerability issues, and the availability of alternative antibiotics reduce its attractiveness for routine pediatric prescribing.

Generic substitution

Even if Pediazole were commercially available, it would compete with low-cost generic therapies. A branded relaunch would face weak pricing power unless it offered a meaningful supply, palatability, or clinical advantage.

What is the financial trajectory for Pediazole?

Pediazole does not appear to have a separately reported public revenue stream. Its financial trajectory is therefore best assessed through market status rather than reported sales.

Period	Financial trajectory	Principal driver
Original commercial period	Positive but mature branded-product revenue	Pediatric antibiotic demand
Generic substitution period	Declining revenue and price compression	Loss of exclusivity
Later commercial period	Low-volume or discontinued status	Therapeutic substitution
Current outlook	No identifiable standalone branded growth	Amoxicillin-led standard of care

Public pharmaceutical companies generally do not disclose revenue for an old product such as Pediazole separately. Any historical sales estimates would require proprietary prescription or channel data from sources such as IQVIA or Symphony Health. Public filings are therefore insufficient to produce a defensible product-level revenue series.

The current financial conclusion is clear: Pediazole has little or no visible standalone revenue contribution, limited pricing power, and no credible basis for a material growth forecast.

Which companies are competing with Pediazole?

Pediazole does not compete primarily against another branded combination product. Its effective competitors are generic and guideline-preferred antibiotics.

Competitor	Competitive position
Generic amoxicillin	Principal first-line substitute for acute otitis media
Generic amoxicillin-clavulanate	Broader-coverage substitute
Cefdinir and other oral cephalosporins	Alternative for selected penicillin-allergic patients
Azithromycin	Alternative macrolide, although resistance limits use
Generic erythromycin products	Partial ingredient-level substitute
Other pediatric suspensions	Compete on palatability, availability, and price

Manufacturers active in these generic categories have greater commercial relevance than the original Pediazole sponsor. Competition is based on contract manufacturing, wholesaler availability, pharmacy inventory, and reimbursement rather than patent differentiation.

What generic entry risks exist for Pediazole?

Generic entry risk is theoretically high because active exclusivity appears absent. In practice, the risk is muted because the market itself is small and clinically outdated.

A new entrant would face four commercial problems:

• Low prescription demand.
• Strong substitution by amoxicillin.
• Minimal ability to charge a premium.
• Manufacturing complexity disproportionate to expected volume.

The most plausible generic-launch scenario would be a shortage-driven or niche supply opportunity, not a major branded launch. A manufacturer might enter if hospitals, pediatric networks, or government buyers created reliable demand. Without contracted volume, the product is unlikely to support attractive returns.

Does Pediazole have biosimilar risk?

No. Biosimilars apply to biological products, while Pediazole is a conventional small-molecule antibiotic combination. The relevant competitive risks are generic substitution, therapeutic substitution, and product discontinuation.

What patent litigation or Paragraph IV challenges affect Pediazole?

No material current Paragraph IV litigation or patent litigation affecting Pediazole is identified. That outcome is consistent with the product’s age, expired exclusivity, and limited commercial value.

A future abbreviated new drug application could theoretically raise patent-certification issues if an applicant cited a still-listed patent. The commercial significance would remain limited unless the FDA listed an active patent or exclusivity period for the specific reference product. No such active protection is apparent from the historical product profile and available FDA reference sources.[4]

How strong is the Pediazole patent estate?

The Pediazole patent estate is commercially weak.

Strength factor	Assessment
Remaining patent life	None of material value
Formulation differentiation	Low
Regulatory exclusivity	None of current significance
Clinical differentiation	Low
Manufacturing complexity	Moderate
Pricing power	Very low
Litigation leverage	Minimal
Relaunch attractiveness	Low without contracted demand

The product may retain technical know-how value in suspension manufacture, but know-how is not equivalent to enforceable exclusivity. The absence of a patent moat makes Pediazole vulnerable to substitution from both direct generic equivalents and unrelated antibiotics.

What is the commercial outlook for Pediazole?

The outlook is flat to declining from an already limited base. Pediazole is unlikely to regain meaningful market share unless a supply disruption affects preferred pediatric antibiotics or a manufacturer identifies a specialized institutional market.

The product’s strongest potential use case would be as a niche alternative where clinicians specifically want the historical combination and a reliable supplier is available. That market would be small and price-sensitive.

Key Takeaways

• Pediazole is an older erythromycin ethylsuccinate and sulfisoxazole acetyl suspension.
• Its original patent and regulatory exclusivity are expired.
• No material active patent estate or current Paragraph IV litigation is identified.
• Amoxicillin and amoxicillin-clavulanate displaced Pediazole in routine pediatric treatment.
• Pediazole has no biosimilar risk because it is a small-molecule drug.
• Public companies do not report a reliable standalone Pediazole revenue stream.
• The commercial opportunity is limited by low demand, generic pricing, and formulation complexity.
• Any future relaunch would be a niche or supply-driven opportunity rather than a major branded growth product.

FAQs

Is Pediazole still available in the United States?

Pediazole has limited or discontinued commercial availability in the United States. Its historical FDA labeling remains useful for identifying the formulation and indications, but labeling does not establish current pharmacy availability.

Is Pediazole the same as erythromycin?

No. Pediazole contains erythromycin ethylsuccinate plus sulfisoxazole acetyl. Erythromycin products contain a macrolide antibiotic without the sulfisoxazole component.

Why was Pediazole discontinued?

The commercial decline is consistent with loss of exclusivity, low demand, manufacturing economics, and replacement by preferred pediatric antibiotics. Discontinuation alone does not establish an FDA safety withdrawal.

Can a generic manufacturer relaunch Pediazole?

A qualified manufacturer could assess an FDA pathway for an equivalent product, but the commercial case is weak. The major barriers are low demand, product-development cost, and competition from inexpensive first-line antibiotics.

Did Pediazole generate significant pharmaceutical revenue?

Pediazole may have generated revenue during its original commercial period, but no current public source provides a reliable standalone revenue series. Its present financial contribution appears immaterial.

References

1. American Academy of Pediatrics. (2013). The diagnosis and management of acute otitis media. Pediatrics, 131(3), e964-e999.
2. U.S. National Library of Medicine. (n.d.). Pediazole: Erythromycin ethylsuccinate and sulfisoxazole acetyl oral suspension. DailyMed.
3. U.S. Food and Drug Administration. (n.d.). Discontinued drug product list.
4. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, commonly known as the Orange Book.