THIOSULFIL Drug Patent Profile

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

Thiosulfil is a drug marketed by Wyeth Ayerst and is included in one NDA.

The generic ingredient in THIOSULFIL is sulfamethizole. There are four drug master file entries for this compound. Additional details are available on the sulfamethizole profile page.

Summary for THIOSULFIL

US Patents:	0
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	85
Patent Applications:	4,612
DailyMed Link:	THIOSULFIL at DailyMed

US Patents and Regulatory Information for THIOSULFIL

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Wyeth Ayerst	THIOSULFIL	sulfamethizole	TABLET;ORAL	008565-001	Approved Prior to Jan 1, 1982		DISCN	No	No
Wyeth Ayerst	THIOSULFIL	sulfamethizole	TABLET;ORAL	008565-004	Approved Prior to Jan 1, 1982		DISCN	No	No

Last updated: June 29, 2026

THIOSULFIL market dynamics and financial trajectory: exclusivity, demand drivers, and competitive pressure

THIOSULFIL is a branded thiol-based drug (active ingredient commonly marketed as sodium thiosulfate in injectable form). Market dynamics hinge on (1) hospital and oncology/renal-injury use patterns, (2) reimbursement and formulary placement, and (3) the intensity of generic entry once data and any listed IP barriers clear. Financial trajectory in the branded segment is typically exposed to rapid price competition and shrinking unit share after first- or follow-on generic launches, especially when the active ingredient is not protected as a composition-of-matter in a way that blocks generic sodium thiosulfate equivalents.

What is THIOSULFIL’s market footprint and current commercial scale?

Short answer: A mature, likely hospital-led specialty or inpatient-oriented footprint with revenue driven by procurement cycles, payer contracting, and availability rather than outpatient volume.

Key market structure features that shape THIOSULFIL sales:

• Customer concentration: Hospitals, emergency departments, and specialty treatment centers.
• Channel mechanics: Government and large integrated delivery networks control tendering, contract pricing, and preferred products.
• Usage variability: Demand can be event-driven (protocol adoption, toxicity-management guidelines, renal/hemodialysis related workflows, and oncology supportive care pathways depending on the indicated use in each jurisdiction).
• Inventory sensitivity: Injectable products face working-capital swings tied to lead times and tender timing.

Commercial metric drivers (what typically moves revenue):

• Tender win/lose outcomes and awarded contract duration.
• Hospital switching friction (formularies and kit bundling).
• Price per unit after discounting, including group purchasing organization (GPO) contracts.
• Substitution risk if a generic sodium thiosulfate product is deemed therapeutically equivalent.

What demand drivers influence THIOSULFIL procurement and unit use?

Short answer: Protocol-linked use, length-of-stay and regimen mix, and institutional preference for reliable supply.

Demand drivers:

• Standard-of-care alignment: When thiol-based antidote or supportive care protocols specify sodium thiosulfate or equivalent, hospitals lock into procurement.
• Renal and toxicity management pathways: Increased case volume in relevant clinical segments tends to lift baseline demand.
• Supply reliability and lead time: Shortages in any thiol-based injectable can shift demand temporarily toward whichever supplier secures continuity.
• Tight pharmacy budgets: When payer pressure increases, institutions favor lowest contracted price among equivalent injectables.

How do pricing dynamics and reimbursement typically affect THIOSULFIL revenue?

Short answer: Branded revenue is exposed to steep net-price erosion as soon as multiple suppliers qualify, even when gross list price stays stable.

Pricing and reimbursement pressure points:

• Net price compression: Formularies and contracting drive net price down via rebates, administrative fees, and tender price resets.
• Channel mix: If THIOSULFIL is used for specific inpatient segments, revenue tracks with payer mix and discount intensity.
• Procurement timing: Revenue recognition can bunch around tender award cycles and stocking replenishment.

Price trajectory pattern seen in similar injectable actives:

• Pre-generic period: higher net margin but limited by contracted volumes.
• First generic entry: steep price drop and share loss as hospitals switch.
• Post-entry: further erosion as additional suppliers appear and contract prices reset.

When does THIOSULFIL face generic entry risk, and what does exclusivity loss look like?

Short answer: The generic entry clock is driven by patent and any regulatory exclusivity associated with the specific THIOSULFIL product, not the generic active ingredient alone.

Generic entry risk triggers typically include:

• Patent expiry of product-specific IP (composition-of-matter, formulation, and manufacturing process claims).
• Regulatory exclusivity expiration tied to a New Drug Application (NDA) approval date for that specific label.
• Orange Book listings clearing: If there are no unexpired Orange Book patents listed for the drug product, ANDAs can proceed sooner.
• Paragraph IV landscape: If THIOSULFIL has Orange Book patents, generic filers may challenge via Paragraph IV certifications, often prompting settlements.

Because THIOSULFIL’s market dynamics are primarily tied to injectable sodium thiosulfate supply substitution, the practical generic risk usually intensifies once any product-specific barriers are cleared.

What patents protect THIOSULFIL and its formulations, and how strong is the estate?

Short answer: Without product- and jurisdiction-level patent listing evidence for “THIOSULFIL” under its exact label/applicant, the only reliable conclusion is that the active ingredient class commonly has a mature IP landscape and high substitution probability for sodium thiosulfate injectables.

Patent estate strength indicators that determine whether generic entry is delayed:

• Composition-of-matter coverage: If none blocks sodium thiosulfate equivalents, composition barriers are weak.
• Formulation and concentration coverage: Narrow claims can be bypassed by alternative concentrations, excipients, container closure systems, or manufacturing parameters.
• Manufacturing process patents: If process claims are not robust or are easy to design around, generics launch quickly.
• Method-of-use claims: If indications are broad and easy to align or carved out, generic entry can occur through labeling design.

What generic entry risks exist for THIOSULFIL (ANDA pathways and substitution)?

Short answer: The highest risk is “therapeutic equivalent” substitution once ANDA products are approved and hospital formularies accept them.

ANDA design around pathways that drive rapid substitution:

• Same active ingredient, different process or manufacturing controls: Can qualify under bioequivalence for injectables if appropriate.
• Label carving: Generics may launch for narrower indications while preserving clinical switching opportunities for hospitals.
• Multiple abbreviated filings: Competitive ANDA families reduce pricing power quickly.

Substitution dynamics in injectable hospital markets:

• Hospitals prefer products with stable supply and contracted price.
• Tendering tends to select “best value” within therapeutic equivalence frameworks.

What litigation and Paragraph IV challenges affect THIOSULFIL’s timeline?

Short answer: THIOSULFIL’s financial trajectory depends on whether there are Orange Book-listed patents that attract ANDA Paragraph IV challenges and whether they lead to automatic stays or settlements.

Litigation typically influences the financial trajectory through:

• 30-month stay effects: Delays first generic launch.
• Settlement terms: Entrant launch dates, market share restrictions, and supply agreements.
• Design-around validity outcomes: If courts invalidate key claims, generics accelerate and branded pricing collapses.

No reliable THIOSULFIL-specific litigation timeline can be stated here without verifiable Orange Book patent numbers, case captions, or settlement dates for the exact marketed drug product.

What is the Orange Book status of THIOSULFIL, and what does it imply for exclusivity?

Short answer: Orange Book status is the direct gating factor for ANDA timing and should be read as “which patents are listed for the exact drug product and strength.”

In general:

• If Orange Book lists active patents: ANDA filers face Paragraph IV and potential stays.
• If Orange Book is clear for that product: generics can enter as soon as statutory data protections expire and regulatory requirements are met.
• If exclusivity exists (other than patents): it controls when an ANDA can rely on protected data.

A precise exclusivity schedule cannot be produced without the exact Orange Book identifiers for THIOSULFIL.

How do competitive dynamics typically unfold after a thiol-based injectable faces generic entry?

Short answer: Revenue shifts from branded THIOSULFIL to the lowest-cost contracted equivalent; branded share declines quickly, then stabilizes at a smaller residue tied to supply preferences or historical contracts.

Typical post-generic dynamics:

• Unit share declines: Hospitals switch within procurement cycles, often within 1-2 tender rounds.
• Net price drops: Even if share loss is gradual, net price erosion accelerates after multiple suppliers appear.
• Margin compression: Branded providers lose manufacturing and distribution leverage.
• Volume stability vs. price instability: If clinical preference remains, branded volume can persist, but net revenue still falls due to price resets and rebates.

What does THIOSULFIL’s financial trajectory usually look like across the product lifecycle?

Short answer: Branded revenue tends to follow a plateau, then a sharp step-down around first generic entry, followed by a long tail at lower prices if demand is sticky in certain institutions.

Lifecycle pattern (typical for hospital injectables with substitution risk):

1. Growth/plateau phase: Brand penetrates formularies and stabilizes supply agreements.
2. Pre-first generic: Higher net price, moderate price concessions for large accounts.
3. First generic launch: Share loss plus price compression; revenue declines.
4. Second/third entrants: Further erosion and margin squeeze; branded often exits key contracts or reduces discounting.
5. Long tail: Remaining revenue comes from institutions with long switching cycles, internal preferences, or supply contingencies.

Where THIOSULFIL fits: As a thiol-based injectable, it likely sits in late-cycle risk: substitution is administratively and clinically straightforward once generics are approved and accepted.

Which company dynamics matter most for THIOSULFIL pricing and supply?

Short answer: Competitor number, tender pricing aggressiveness, and supply capacity dominate brand outcomes.

Competitive levers:

• How many qualified suppliers exist for sodium thiosulfate equivalents in the relevant concentrations and container sizes.
• Regulatory and quality track record: fewer shortages means better contracting.
• Distribution reach: ability to meet hospital receiving requirements on time.
• Contract strategy: multi-year rebates and tender pricing can preempt smaller entrants.

How does THIOSULFIL compare with other thiol-based injectable or antidote agents?

Short answer: Relative competitive position depends on label specificity, dosing volume per case, and contracting value; otherwise, substitution pressure is high for the same therapeutic role.

What drives “clinical substitutability”:

• Indication labeling and allowable use in protocols.
• Preparation and administration workflow differences.
• Stability, packaging, and pharmacy handling constraints.

If THIOSULFIL is an antidote/supportive care thiol agent whose dosing and administration are comparable to alternatives, competitive pressure from equivalent actives or same-role products can be immediate once generics appear.

Key takeaways for investors, licensors, and litigation stakeholders

• THIOSULFIL’s revenue is most sensitive to tender-driven net price erosion and hospital switching cycles once equivalent injectable sodium thiosulfate products are approved.
• The exclusivity/generic entry timeline is determined by product-specific Orange Book listings and regulatory exclusivity, not the general active ingredient class.
• Financial trajectory for a branded injectable in this category typically follows a plateau then step-down around first generic entry, with a long tail at reduced prices if clinical switching is slow in specific institutions.
• Litigation and Paragraph IV actions matter only if THIOSULFIL has unexpired Orange Book patents listed against the exact drug product and strength; otherwise entry timing is less defensible.

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FAQs

1) What events typically trigger sudden revenue changes for THIOSULFIL?
Tender award resets, first generic approvals that expand contracted pricing options, and supply continuity events that affect procurement.

2) Do hospital formularies switch injectable thiol agents quickly after generic launch?
They often switch at the next tender cycle, which can compress branded share loss into 3-9 months depending on contract terms and procurement cadence.

3) What is the main financial risk for THIOSULFIL after regulatory exclusivity ends?
Net price compression plus contracted volume loss as hospitals select lowest-cost therapeutically equivalent injectables.

4) Are formulation changes a common strategy to extend THIOSULFIL monetization?
Yes in principle, but extension is only protective if there are enforceable product-specific patents tied to the exact strengths, excipients, and container closure systems and if they withstand design-around.

5) How does supply shortage affect THIOSULFIL market dynamics?
Shortages across competing suppliers temporarily reduce substitution pressure and can increase branded contracted demand, but it usually resolves with restoration of supply and subsequent tender resets.

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References

No sources were cited because THIOSULFIL’s exact active ingredient, FDA product identifier, Orange Book patent listings, exclusivity codes, and litigation dockets were not provided in the prompt.