Drugs in MeSH Category Abortifacient Agents, Nonsteroidal

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Gland	CARBOPROST TROMETHAMINE	carboprost tromethamine	INJECTABLE;INJECTION	217657-001	Aug 7, 2023	AP	RX	No	No
Sola Pharms	CARBOPROST TROMETHAMINE	carboprost tromethamine	INJECTABLE;INJECTION	216824-001	May 19, 2023	AP	RX	No	No
Assertio Speclty	OTREXUP	methotrexate	SOLUTION;SUBCUTANEOUS	204824-002	Oct 11, 2013		DISCN	Yes	No	11,684,723		Y
Acq Pharma	MISOPROSTOL	misoprostol	TABLET;ORAL	210201-002	Jul 2, 2019	AB	RX	No	No
Pfizer	CYTOTEC	misoprostol	TABLET;ORAL	019268-003	Sep 21, 1990	AB	RX	Yes	No

Market dynamics and patent landscape for NLM MeSH “Abortifacient Agents, Nonsteroidal” drugs: who owns exclusivity, what expires next, and where generics face patent barriers

Last updated: June 7, 2026

Abortifacient Nonsteroidal (MeSH) is a narrow pharmacologic bucket with limited globally dominant products. In practical market terms, the space is driven by (1) mifepristone in combination with a prostaglandin for medical abortion, and (2) NSAID-class agents used for pain management around abortion care. The patent landscape for this MeSH category therefore splits into two tracks: abortion regimen IP (often method-of-use, combination, and manufacturing patents) and NSAID analgesic IP (formulation, polymorph, and process patents), with separate FDA regulatory status and generic entry risk.

This report maps the competitive and patent dynamics that matter for investment, licensing, and litigation decisions: exclusivity timelines, Orange Book status, and the types of patents that typically block Paragraph IV generic or direct-to-market competition in the United States for the relevant abortion-care medicines.

Which abortifacient NSAID-related drugs define the market dynamics in practice?

Featured snippet answer: The MeSH category is clinically anchored by mifepristone-based medical abortion regimens, while NSAID nonsteroidals typically act as adjunct analgesics; market dynamics track the abortion-regimen exclusivity and the separate NSAID patent estates for pain control.

How “Abortifacient Agents, Nonsteroidal” is interpreted operationally

MeSH taxonomies are used for indexing and search, not for regulatory product grouping. Operationally, the care pathway for medical abortion uses:

• A progesterone receptor antagonist (mifepristone) to initiate uterine changes
• A uterotonic/prostaglandin (agent varies by country and labeling)
• NSAIDs (commonly ibuprofen-class) for pain control

That creates a two-layer competitive landscape:

1. IP and regulatory exclusivity for the abortion regimen itself (mifepristone and the companion uterotonic product, including combination and method-of-use claims where asserted)
2. Separate IP and generic competition dynamics for NSAID analgesics used during abortion care

What NSAID products most often drive payer and procurement spend

NSAIDs are off-patent in many markets, so their contribution is mainly volume and switching economics rather than sustained exclusivity. The durable value is typically in controlled or specialty abortion-regimen drugs, not in older NSAIDs.

For business decisions, the NSAID segment is still relevant because:

• Payers and health systems bundle abortion-care services, and NSAID formularies affect total cost of care
• Patent litigation strategy for abortion regimens can spill over into combination-of-use narratives in labeling disputes
• Some NSAIDs retain patent activity through controlled-release, fixed-dose combinations, or specific crystalline forms

What patents protect mifepristone-based medical abortion regimens that overlap with NSAID adjunct use?

Featured snippet answer: The strongest and most litigated IP in medical abortion typically concentrates on mifepristone compositions and manufacturing, with method-of-use and regimen/combo claims appearing depending on the assignee and jurisdiction.

Composition and manufacturing patents that frequently matter

Mifepristone patent estates in the US and major jurisdictions commonly include:

• Active pharmaceutical ingredient (API) composition claims (including polymorph/crystal form)
• Formulation claims for tablet compositions
• Process claims for synthesis and purification
• Method-of-use claims tied to dosing schedules and combination administration

Even where NSAIDs are only adjuncts, plaintiffs and defendants sometimes dispute whether regimen claims cover adjunct administration or whether labeling and real-world use extend into claim scope.

Combination and method-of-use claims: where disputes usually occur

For abortion regimens, contested issues tend to include:

• Whether a claim requires a specific sequential dosing pattern (not just co-administration)
• Whether the claim scope includes administration of an NSAID as part of the claimed “method”
• Whether generic substitution changes the regimen in a way that avoids claim elements

In practice, Paragraph IV and litigation risk is highest when:

• The Orange Book lists patents tied to the NDA for the regimen drug
• The listed patents include method-of-use claims that a generic carve-out cannot easily avoid

How many patents cover relevant abortion regimen medicines, and how concentrated is ownership?

Featured snippet answer: Patent coverage is usually concentrated around a small number of core assignees and key NDA-linked patents rather than distributed across many independent owners.

Concentration pattern investors look for

A defensible estate typically shows:

• One or two dominant families for composition/formulation plus process
• A handful of US patents listed in the FDA Orange Book for the marketed NDA
• Geographic layering where US expires first but EP/WO keep exclusivity longer in select markets

Ownership review framework for licensing and M&A

For exclusivity capture and diligence, the core asks are:

• Which assignee holds the Orange Book-listed patents for the NDA
• Whether the estate includes terminal disclaimer filings that accelerate expiration
• Whether continuations indicate attempts to extend exclusivity via claim-margin improvements

When does abortion-regimen exclusivity and US patent protection lose exclusivity?

Featured snippet answer: US exclusivity timing depends on NDA marketing exclusivity, patent term adjustments, and listed patent expiration dates; in medical abortion, exclusivity often ends years before some jurisdictions because patent families expire on different schedules.

US timeline mechanics that drive generic entry risk

Generic entry under US law is driven by:

• Patent expiration of Orange Book-listed patents
• Exclusivity periods for the NDA (5-year and 3-year exclusivity can apply to certain circumstances)
• Bottlenecks such as REMS (for certain abortion-care medicines) that can affect market access, even after patents expire

What typically happens to NSAID patents by comparison

NSAIDs used as adjunct analgesics are commonly off-patent. Their exclusivity usually plays a minor role versus regimen drugs.

What is the Orange Book status of the key abortion-care medicines that intersect this MeSH class?

Featured snippet answer: The Orange Book governs the dispositive US patent landscape for generic entry; the decisive list is the Orange Book “patents” tied to the specific NDA(s) for abortion regimen drugs, not the MeSH category.

How to interpret Orange Book listings for market forecasts

For any target product:

• Focus on listed patents with expiration dates and whether they are “patent” vs “exclusivity” entries
• Identify whether method-of-use patents are listed because they are frequently asserted in Paragraph IV challenges
• Use “use code” and “dosage form” metadata to align claim scope to the generic’s proposed label

NSAIDs: Orange Book listings are often less value-dense

Because many NSAIDs are generics already, remaining Orange Book activity is often around:

• Specific NDA strengths or dosage forms
• Controlled-release variants
• Combination products

Which companies are challenging or defending patents for abortion-regimen drugs adjacent to NSAID adjunct care?

Featured snippet answer: Litigation is usually concentrated among brand holders and major generic filers with parallel Paragraph IV filings; NSAID adjuncts are typically not the center of the patent fight, but may appear in method-of-use disputes.

Parties that matter for Paragraph IV strategy

In US practice, the relevant players often include:

• Brand originators and their assignees
• Large generic manufacturers that file ANDAs and submit Paragraph IV certifications
• Law firms and litigation boutiques with repeat experience in Orange Book and REMS-linked disputes

Where NSAID references enter litigation

Common entry points:

• Labeling content about pain management and whether a method-of-use claim incorporates adjunct NSAID administration
• “Carve-outs” in generics that omit NSAIDs from instructions and whether omission avoids claim elements

How strong is the patent estate for mifepristone and what claim types dominate?

Featured snippet answer: Patent strength is highest where the estate contains Orange Book-listed composition, formulation, and method-of-use claims that map cleanly to branded use and dosing regimens.

Claim-type dominance: the practical view

For medical abortion medicines, investors value estates with:

• Composition/formulation coverage that blocks “easy design-around”
• Process claims that are hard to non-infringe without a different manufacturing route
• Method-of-use claims that are directly reflected in labeling

Conversely, weaker estates show:

• Only late-expiring formulation patents that do not align with the generic’s intended dosage form
• Claims that are sensitive to label wording and can be addressed by certified-label changes

What generic entry risks exist for abortion-regimen medicines in the US after patent cliffs?

Featured snippet answer: Generic entry risk spikes when Orange Book-listed patents expire and remaining exclusivity is minimal; method-of-use patents can still delay full label parity if courts narrow or if label wording is litigated.

Scenario planning for market entry

Post-expiration, generics typically time market entry around:

• Final resolution of infringement disputes for any actively litigated patents
• Eligibility to receive approval with sufficient label and REMS compliance
• Supply chain readiness for API and tablet manufacturing

How NSAID adjuncts change the economics

Because NSAIDs are widely available, they do not typically constrain market entry for the abortion regimen product. They can, however, influence payer contracting and patient experience, which indirectly affects net sales and adoption curves.

How does the patent landscape for NSAID analgesics used in abortion care compare with abortion-regimen patents?

Featured snippet answer: NSAID patents are generally older and more fragmented by dosage form and variant; abortion-regimen patents are fewer families with higher litigation intensity tied to NDA-linked exclusivity.

NSAID estate characteristics

Typical remaining IP themes for NSAIDs include:

• Controlled-release and delayed-onset formulations
• Fixed-dose combinations (rare in this MeSH-specific use context but common in analgesic space)
• Crystalline form and solid-state stability claims for specific salts

Why the MeSH grouping can mislead diligence

A diligence process should not treat “Abortifacient Agents, Nonsteroidal” as a single unit of IP. It is more accurate to diligence:

• The abortion-regimen API and product-level IP
• Then separately diligence the NSAID brand variants, if they are relevant to your commercial product or partnership

What patent litigation affects medical abortion medicines in this space?

Featured snippet answer: Litigation risk is concentrated around Orange Book-listed patents for the regimen drug and, in some cases, method-of-use claims related to dosing regimens.

Litigation pathways that matter to investors

• Paragraph IV ANDA challenges leading to automatic stays (when eligible)
• Infringement actions tied to method-of-use and formulation claims
• Settlements that define “launch dates” or “design-around” rules

Settlement patterns that can shift launch economics

Settlements often allocate:

• A defined “effective entry date” for the first filer
• Limitations on label language
• Patent-specific design-around constraints
• Confidential terms that can include inventory timing and supply restrictions

How does FDA regulatory status (NDA vs ANDA vs REMS) shape market timing?

Featured snippet answer: FDA approval pathway and REMS implementation can delay or accelerate actual availability beyond legal expiration.

Regulatory levers that affect launch speed

• NDA exclusivity and the timeline to ANDA approvals
• Labeling and any requirement to comply with a REMS program
• Switching and distribution models, which can slow market penetration even after approvals

What formulations are protected by patents, and how do they block design-around?

Featured snippet answer: For regimen drugs, formulation and polymorph claims block straightforward generic replication; for NSAIDs, only certain variants retain meaningful IP.

Formulation patent themes

For regimen drugs:

• Solid-state control of dissolution and stability
• Tablet composition and excipient constraints
• Processing steps that affect bioavailability

For NSAIDs:

• Solid-state variants and controlled-release delivery
• Fixed-dose combinations and specific tablet architectures

Key Takeaways

• The MeSH category bundles two economic drivers: abortion-regimen exclusivity (where patent estates and Orange Book listings are decisive) and NSAID adjuncts (usually off-patent, with remaining value in variants and combinations).
• Patent strength and generic entry risk track NDA-linked, Orange Book-listed claims, especially method-of-use and composition/formulation families for regimen drugs.
• NSAID IP typically has lower system impact on market entry timing for abortion regimens, but can still matter for payer contracting and for specific branded NSAID variants with residual patent protection.
• Litigation and settlement terms that define effective launch dates usually hinge on Orange Book-listed patents for the regimen drug, not the adjunct NSAID.

FAQs

1. Which Orange Book-listed patents most often determine ANDA launch timing for medical abortion regimen drugs?
2. Do method-of-use claims in abortion regimens cover NSAID adjunct administration in practice?
3. What generic design-around strategies avoid infringement for mifepristone-related formulation and process patents?
4. How do REMS requirements interact with patent expiration to affect actual market availability?
5. Which NSAID dosage forms retain nontrivial patent estates relevant to abortion-care pain management?

References

1. National Library of Medicine. MeSH: “Abortifacient Agents, Nonsteroidal.” U.S. National Library of Medicine.
2. U.S. FDA. Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations. U.S. Food and Drug Administration.
3. U.S. FDA. Drug Approval Process and Regulatory Information. U.S. Food and Drug Administration.