Drugs in MeSH Category Purinergic P2Y Receptor Antagonists

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Mylan	TICLOPIDINE HYDROCHLORIDE	ticlopidine hydrochloride	TABLET;ORAL	075161-001	Sep 13, 1999		DISCN	No	No
Watson Labs	TICLOPIDINE HYDROCHLORIDE	ticlopidine hydrochloride	TABLET;ORAL	075309-001	Apr 26, 2000		DISCN	No	No
Teva	TICLOPIDINE HYDROCHLORIDE	ticlopidine hydrochloride	TABLET;ORAL	075149-001	Aug 20, 1999		DISCN	No	No
Apotex	TICLOPIDINE HYDROCHLORIDE	ticlopidine hydrochloride	TABLET;ORAL	075089-001	Jul 1, 1999		DISCN	No	No

Last updated: June 12, 2026

Market dynamics and patent landscape for NLM MeSH Class: Purinergic P2Y Receptor antagonists

Global demand for purinergic P2Y receptor antagonists is shaped by a narrow pipeline set focused on inflammatory, thrombotic, and pain pathways, with patent estates that typically split across (1) P2Y subtype pharmacophores, (2) salts and formulations, (3) method-of-use, and (4) sometimes delivery or combination regimens. Near-term commercialization is concentrated in a small number of assets, so single-asset patent term cliffs can materially shift competitive intensity.

What matters commercially

• Patent coverage is usually subtype- and scaffold-specific (P2Y1/P2Y2/P2Y4/P2Y6/P2Y12/P2Y14), with the strongest exclusivity often tied to the original compound claims and early method-of-use claims.
• Formulation and dosing regimen patents exist in many estates, but they rarely block generic entry unless a product is clearly constrained to a specific salt, crystal form, or dosing schedule.
• Second-wave IP (combination therapy, new indications, and prodrug/delivery improvements) can extend practical exclusivity beyond primary composition expiration.
• Competitive entry risk is dominated by Orange Book listing status (small molecules) and, where relevant, by the strength and remaining life of method-of-use claims and any exclusivity tied to clinical data exclusivity or Hatch-Waxman route.

What matters legally

• For approved small molecules, Paragraph IV challenges usually hinge on whether the generic’s label triggers the same method-of-use carveouts and whether unexpired composition claims are asserted.
• For biologic-like purinergic modalities (rare in this MeSH class), biosimilar routes are less relevant than small molecule generic routes.
• Settlement patterns tend to correlate with the age of the reference product and whether the brand’s key claims are broad composition claims versus narrower formulation or dosing claims.

Scope note (how this is used for R&D and litigation planning)

• “Purinergic P2Y receptor antagonists” is a MeSH class. The commercial landscape includes drugs that antagonize P2Y receptors, primarily small molecules.
• A complete, asset-level patent matrix requires drug-identifying inputs (product name and active ingredient) and the specific FDA reference listing(s). Without those, any mapping risks producing incomplete or incorrect patent coverage.

Which purinergic P2Y receptor antagonists drive the market and patent battleground?

Featured snippet answer: The market is concentrated in a limited set of P2Y-targeting small molecules where the key exclusivity is split between composition-of-matter and one or more method-of-use claims, with formulation patents creating secondary barriers only when tightly aligned to the marketed salt/form.

How do P2Y subtype choices map to commercial demand?

P2Y receptor antagonism is pursued across several therapeutic themes, and the patent estate typically tracks the biology:

• P2Y12 (thrombotic disease)
  Antagonists can compete with or complement existing antiplatelet standards. Patent estates often overlap with salt/form specifics and dosing regimens used in labeled indications.
• P2Y2 / P2Y4 / P2Y6 (inflammation, epithelial disorders, pain signaling)
  These programs often pursue anti-inflammatory and symptom-control indications. Patent portfolios often emphasize scaffold and formulation, plus method-of-use for specific inflammatory biomarkers or clinical phenotypes.
• P2Y14 and related immune modulatory targets
  Estates often rely on composition claims and method-of-use around immune-driven disease.

Why do some P2Y estates look “stronger” than others?

• Stronger estates: broad composition claims that read across salt forms and stereochemistry, plus defensible method-of-use claims that match the label.
• Weaker estates: narrow formulation claims (specific polymorph/crystal form), or method-of-use claims that are not recited in the final label.

What patents protect P2Y receptor antagonists composition-of-matter vs formulation vs method-of-use?

Featured snippet answer: P2Y antagonist patent estates usually fall into four layers: core compound (composition), subtype selectivity/scaffold variants, formulation/delivery (salt, polymorph, particle size), and method-of-use (label-linked indication claims).

Composition-of-matter: what claim types dominate?

Common composition claim themes in P2Y antagonist portfolios:

• Generic Markush claims covering broad scaffold classes
• Specific exemplified compounds with narrower fallback claims
• Stereochemical variants, tautomers, solvates
• Salt forms (often tied to a crystallization workflow)

Formulation and manufacturing patents: what do they typically cover?

• Salt and hydrate/solvate selection
• Polymorph/crystal form
• Particle size distribution and milling parameters (especially for oral solids)
• Tablet/capsule compositions and excipient systems
• Controlled-release or taste-masking systems where relevant

Method-of-use: what creates the litigation trigger?

• Indication-specific claims aligned to the clinical label
• Combination therapy claims (P2Y antagonist + standard of care)
• Patient population claims that correlate to clinical inclusion criteria
• Biomarker-defined methods (less often used as sole exclusivity, but can support injunction strategies)

When does exclusivity end for purinergic P2Y antagonists: patent expiration vs Hatch-Waxman exclusivity?

Featured snippet answer: Exclusivity ends when the last relevant Orange Book-listed patent expires or is successfully designed around, with practical exclusivity also influenced by any non-patent data exclusivities and by whether method-of-use claims remain enforceable against the label.

How to structure an expiration timeline (what to calculate)

For each marketed P2Y antagonist asset, the practical exit date is the maximum of:

• Latest expiration among listed patents in the Orange Book (composition, formulation, method-of-use)
• Any pediatric exclusivity extension (if applicable)
• Any granted regulatory exclusivity tied to the approval pathway (data exclusivity, orphan exclusivity where relevant)

What usually drives the last 12 to 24 months?

• Injunction risk from unexpired composition or method-of-use claims
• Narrow design-around opportunities for generics if the active is tightly defined in composition claims
• Settlement agreements that convert to a launch date with permitted entry windows

How strong is the patent estate for P2Y receptor antagonists and where do generics carve around?

Featured snippet answer: Estate strength hinges on whether the claims cover the marketed active, including stereochemistry and salt form, and whether method-of-use claims match the approved label. Estates with broad composition claims and label-aligned method-of-use claims generally deter Paragraph IV design-arounds.

Typical generic design-around pathways

• Switching salt form or crystallization state (only works if composition claims are not salt-broad and formulation claims are not asserted)
• Using alternative stereochemistry (only works if claims do not cover all stereoisomers or if the chosen isomer is non-covered)
• Reformulating with different excipient systems (only helps when formulation claims are narrow and the generic is not forced into infringement by the label)
• Avoiding the method-of-use claim by label carveouts (label-driven constraints are central in Hatch-Waxman disputes)

Litigation posture patterns seen in P2Y programs

• Brands that list both composition and method-of-use patents often assert method-of-use to keep the generic off-label or seek launch delay.
• Brands with only formulation patents face more design-around freedom unless the marketed product’s exact formulation is required for bioequivalence.

What is the Orange Book status of P2Y receptor antagonists and which patents are Orange Book-listed?

Featured snippet answer: Orange Book status is the single most decision-relevant index for small-molecule P2Y antagonists because it identifies the specific patents the NDA holder listed as tied to the drug product. For most assets, the Orange Book contains at least one composition-of-matter and often additional formulation and method-of-use listings.

How Orange Book listings translate into launch risk

• If Orange Book includes method-of-use patents, Paragraph IV challenges typically focus on whether the generic’s proposed label will infringe.
• If Orange Book includes formulation patents tied to salt form or polymorph, entry depends on whether the generic can match bioequivalence without infringing the formulation claims.

Which companies are developing or commercializing P2Y receptor antagonists and how do their portfolios differ?

Featured snippet answer: Competitive positioning in P2Y antagonism is dominated by a small set of originators with head-start composition claims, while challengers usually rely on design-arounds and label carveouts to mitigate method-of-use exposure.

Portfolio archetypes by company type

• Originators: file early broad compound claims, then add continuation patents for improved salts, crystal forms, or combination methods.
• Late entrants / challengers: focus development on alternative salts/polymorphs or alternative dosing to reduce formulation infringement risk, then attack method-of-use claims via label strategy.

What patent litigation affects P2Y receptor antagonist drugs: Paragraph IV, settlements, and injunction risk?

Featured snippet answer: Litigation outcomes typically depend on the breadth of composition claims and whether method-of-use claims are aligned to the generic’s proposed label. Settlements usually define a market entry date tied to the brand’s perceived weakest remaining claim.

How to evaluate litigation risk quickly

For each case, the decision tree is:

• Are the asserted patents composition-of-matter or method-of-use?
• Does the generic’s proposed label fall within the protected indication?
• Did the parties settle, and if so, what launch date and triggers apply?
• Are there multiple defendants with staggered certifications (common in crowded generic filings)?

Common settlement terms that matter commercially

• Carveout indications
• Launch date with exclusivity carveouts
• Stipulated court dismissal with trigger events (often linked to regulatory milestones)

How do P2Y receptor antagonist patent estates compare with other purinergic targets like P2X antagonists?

Featured snippet answer: Compared with P2X antagonists, P2Y antagonist estates often show more label-linked method-of-use claims because many P2Y indications overlap with specific clinical regimens (thrombotic and immune-inflammatory phenotypes). P2X estates can be more chemistry-heavy with fewer label-dependent method claims, depending on target biology.

Practical comparison metrics

• Number of Orange Book-listed patents (if applicable)
• Share of method-of-use claims among asserted patents
• Remaining life of key composition claims at the time of generic filings
• Breadth of claims around salt forms, stereochemistry, and delivery systems

What generic entry risks exist for purinergic P2Y receptor antagonists?

Featured snippet answer: Generic entry risk is high when there is (1) no unexpired composition claim covering the marketed API, (2) either no method-of-use Orange Book listing or a strong label carveout strategy, or (3) settlement terms that permit earlier launch.

Entry risk categories for portfolio planning

• High: composition claims near expiration; method-of-use claims narrow or not Orange Book-listed
• Medium: composition still protected but formulation and method claims are weaker
• Low: broad composition plus label-aligned method-of-use remain unexpired, with recent litigation supporting enforceability

What formulations are protected by P2Y antagonist patents: salt forms, polymorphs, and dosing regimens?

Featured snippet answer: Formulation protection usually targets the specific marketed salt or polymorph and the manufacturing pathway for reproducible solid-state performance. Dosing regimen protection matters mainly where the label is tightly tied to the claimed schedule.

Typical protected formulation elements

• Salt identity and conversion profile
• Solid-state form (polymorph, hydrate)
• Particle size limits linked to dissolution profile
• Specific excipient compositions
• Controlled-release mechanisms where used

What FDA regulatory status affects market timing for P2Y receptor antagonists?

Featured snippet answer: FDA approval pathway and exclusivity type determine the timing of generic/competitor entry independent of patents, while label content drives method-of-use infringement analysis.

Key regulatory timing levers

• 505(b)(2) vs ANDA routes (if applicable to competitive entries)
• Data exclusivity grants that delay certain 505(b)(2) and some ANDA submissions
• Orphan drug exclusivity (when applicable)
• Patent term adjustments (PTA) that extend patent life

Key Takeaways

• Patent estates for P2Y receptor antagonists typically stack composition claims with salt/formulation protection and label-aligned method-of-use coverage; the last 12 to 24 months of exclusivity are usually driven by whether Orange Book method-of-use patents remain enforceable.
• Generic entry risk is materially lower when claims cover stereochemistry, salt form, and method-of-use aligned to the approved label, or when recent litigation supports enforceability.
• Market dynamics concentrate around a limited number of assets; as a result, single patent cliffs or settlement-defined launch dates can reprice competitive intensity quickly.
• For business decisions, the decision point is the remaining life of the last relevant Orange Book-listed patents, then the infringement trigger created by the generic’s proposed label.

FAQs

1) How do Orange Book method-of-use listings for P2Y antagonists change Paragraph IV strategy?
They increase label-infringement leverage, making label carveouts and certification decisions central to whether a generic can launch without triggering infringement.

2) Do P2Y antagonist formulation patents (polymorph/crystal form) reliably block generics?
They block entry only when the marketed product’s solid state and manufacturing pathway are difficult to reproduce without infringing the claimed formulation features.

3) When multiple P2Y antagonists target different subtypes, how do patent strategies diverge?
They diverge by subtype-selective pharmacophores and by whether the primary claims are broad enough to cover subtype variants and by how label-linked the method-of-use claims are.

4) What settlement terms most often govern effective launch timing in P2Y antagonist disputes?
Launch dates tied to regulatory milestones plus carveouts that restrict the generic’s label to avoid method-of-use infringement.

5) How can patent term adjustments and pediatric exclusivity shift P2Y antagonist exclusivity cliffs?
They can extend the effective last-claim expiration beyond the baseline patent expiration date, shifting the calendar for eligible generic launches.

References

(No sources were cited because no specific P2Y antagonist assets, active ingredients, FDA NDA numbers, Orange Book listings, or litigation case details were provided.)