United States Patent 10,195,205: Scope, Claim Construction, Expiry and Patent Landscape for Elinzanetant

U.S. Patent No. 10,195,205 protects treatment of hot flushes with the dual neurokinin-1/neurokinin-3 antagonist elinzanetant, including its crystalline anhydrate Form 1. The patent is a method-of-treatment patent, not the core composition-of-matter patent for the active ingredient. Its principal commercial value depends on whether elinzanetant is approved and marketed for vasomotor symptoms before patent expiry and whether the patent is listed in the FDA Orange Book.

The issued patent was granted on February 5, 2019. Its claims cover administration of the specifically identified molecule, pharmaceutically acceptable salts, oral administration, symptom relief, and Form 1. The patent does not expressly claim a dosage, dosing frequency, patient subgroup, formulation excipient system, manufacturing process, or treatment duration.

What does U.S. Patent 10,195,205 protect?

U.S. Patent 10,195,205 protects a method of treating hot flushes by administering elinzanetant, identified in the claims by its full chemical name and formula A. The patent covers:

Claim	Protected subject matter	Principal limitation
1	Treatment of hot flushes	Administration of elinzanetant or a pharmaceutically acceptable salt
2	Treatment of hot flushes	Claim 1 compound must be crystalline anhydrate Form 1
3	Treatment of hot flushes	Oral administration that alleviates hot-flush symptoms
4	Treatment of hot flushes	Oral administration of crystalline anhydrate Form 1

The claims are directed to a human patient in need of treatment. They therefore require a therapeutic-use context rather than merely making, selling, or possessing elinzanetant.

The relevant molecule is elinzanetant, also known in development programs as BAY 3427080 and previously associated with the development code NT-814. It is a dual NK-1/NK-3 receptor antagonist investigated for menopausal vasomotor symptoms.

How broad are the claims in U.S. Patent 10,195,205?

Claim 1: broadest independent claim

Claim 1 is the broadest claim. It requires proof of:

A human patient in need of treatment.
Hot flushes as the condition being treated.
Administration of an effective amount.
Elinzanetant or a pharmaceutically acceptable salt.

The claim does not limit:

Route of administration.
Dose.
Dose interval.
Treatment duration.
Menopausal status.
Severity or frequency of hot flushes.
Whether the patient has cancer-related, surgical, natural, or medication-induced vasomotor symptoms.
Use alone or in combination with another therapy.
Particular pharmaceutical formulation.

The reference to a "dual NK-1/NK-3 receptor antagonist" does not broaden the claim to every dual antagonist. The claim identifies one specific chemical compound by structure and chemical name. A different dual NK-1/NK-3 antagonist would not literally fall within claim 1.

The term "effective amount" is a functional therapeutic limitation. A defendant could challenge infringement by arguing that the administered amount did not produce the claimed treatment effect. In practice, the claim would likely be assessed against the product label, clinical protocol, prescribing instructions, and actual use.

Claim 2: Form 1 limitation

Claim 2 narrows claim 1 to crystalline anhydrate Form 1. This limitation is important because polymorph claims can separate the marketed solid form from other forms of the same active ingredient.

A product would need to contain or deliver the claimed Form 1 material at the relevant point in the treatment method. The claim does not specify particle size, crystallinity percentage, purity threshold, storage condition, or analytical method. Those issues would ordinarily be resolved through claim construction and analytical evidence, including X-ray powder diffraction, thermal analysis, solid-state NMR, water-content testing, or related methods disclosed in the patent family.

Claim 3: oral administration and symptom relief

Claim 3 overlaps substantially with claim 1 but adds two express limitations:

The drug is administered orally.
Oral administration is effective to alleviate hot-flush symptoms.

Claim 3 is not limited to Form 1. It covers the claimed molecule and pharmaceutically acceptable salts in any orally deliverable form that produces the required therapeutic result.

The phrase "effective to alleviate symptoms of hot flushes" creates a results-based limitation. It could be satisfied by evidence of reduced frequency, reduced severity, reduced duration, or an equivalent clinically recognized improvement, depending on the specification and prosecution history.

Claim 4: narrowest issued claim

Claim 4 combines the limitations of claims 2 and 3. It requires:

Human treatment for hot flushes.
Oral administration.
Elinzanetant or a pharmaceutically acceptable salt.
Crystalline anhydrate Form 1.
Alleviation of hot-flush symptoms.

Claim 4 is narrower than claim 2 because it requires oral administration and symptom relief, and narrower than claim 3 because it requires Form 1.

What is the patent status and expected expiration date?

Item	Data
U.S. patent	10,195,205
Patent title	Treatment of hot flushes with NK-1/NK-3 receptor antagonists
Grant date	February 5, 2019
Patent type	Method of treatment
Applicant/assignee	Bayer-related patent interests
Earliest priority	December 2014
Expected nominal expiry	December 2035
Patent term basis	Twenty years from the applicable earliest nonprovisional or international filing date
Patent term adjustment	Must be checked in the USPTO patent record
Patent term extension	Potentially available only if statutory requirements are met after regulatory approval

The practical expiry date should be taken from the USPTO patent-term data rather than calculated solely from the grant date. A patent term extension under 35 U.S.C. § 156 could affect the effective exclusivity period if the statutory requirements are satisfied. A patent term adjustment under 35 U.S.C. § 154 can also modify the expiration date.

The patent does not receive a new 20-year term from its 2019 grant. Its commercial life is tied to the earlier priority and filing chain.

What is the Orange Book status of U.S. Patent 10,195,205?

A method-of-treatment patent can be submitted for Orange Book listing if it claims an approved drug or an approved method of using that drug and satisfies FDA listing requirements. FDA Orange Book listing is not automatic merely because a patent exists.

The relevant questions are:

Orange Book issue	Analysis
Approved drug	Elinzanetant must have an approved NDA before the patent can have product-specific Orange Book relevance
Patent type	The patent claims a method of use, which can qualify for listing if tied to an approved indication
Listed indication	The approved labeling must correspond materially to treatment of hot flushes or vasomotor symptoms
Use code	FDA would assign a use code describing the protected method
Generic certification	An ANDA applicant could be required to submit a Paragraph IV certification if the patent is listed and not carved out
Patent expiration	The listed patent would generally block approval until expiry unless successfully challenged or otherwise removed

The patent’s claim language is sufficiently specific to support a method-of-use listing if the product is approved for the claimed indication. A generic applicant could attempt a section viii statement to omit the protected indication, but that route would be difficult if hot-flush treatment is the principal or only approved use.

FDA Orange Book practice is governed by the Federal Food, Drug, and Cosmetic Act, FDA regulations, and the agency’s patent-listing guidance. The patent record alone does not establish whether Bayer submitted this patent for listing or which use code was assigned.[2]

How does the patent affect Paragraph IV challenges?

A generic applicant seeking approval of elinzanetant could face several certification strategies.

Paragraph IV certification

A Paragraph IV certification would assert that the patent is invalid, unenforceable, or not infringed. Potential arguments could include:

The claims are anticipated by earlier disclosure of elinzanetant for hot flushes.
The claimed use would have been obvious from NK-1/NK-3 antagonist literature and earlier clinical data.
The Form 1 limitation lacks novelty or inventive step over prior solid-form disclosures.
The term "effective amount" is indefinite or insufficiently supported.
The claims lack written description or enablement across their full scope.
The method was publicly used or disclosed before the critical date.
The patent is not infringed because the proposed labeling omits hot-flush treatment.

If the patent is listed in the Orange Book, a timely Paragraph IV notice could trigger a 30-month stay of FDA approval under the Hatch-Waxman framework, subject to the statutory conditions and litigation timing.[3]

Section viii carve-out

A section viii statement could be available if the generic applicant omits the patented hot-flush indication from its labeling and seeks approval for a noninfringing use. That strategy would have limited value if hot-flush treatment is the only commercially meaningful indication or if the proposed label still encourages the patented use.

Infringement exposure

For a method claim, direct infringement generally requires a person to practice the claimed method. Generic-label litigation often focuses on whether the proposed labeling will induce physicians and patients to perform the patented method. The label, promotional material, dosing instructions, and disease indication are central evidence.

What patent protection exists for Form 1?

Form 1 is commercially significant because claims 2 and 4 do not cover every physical form of elinzanetant. They cover crystalline anhydrate Form 1.

Scope of Form 1 protection

The claims do not expressly cover:

An unrelated polymorph.
An amorphous form.
A hydrate.
A solvate.
A co-crystal.
A different salt.
A formulation that contains only a different solid form.

The scope depends on whether the administered product contains Form 1 and whether the form remains present in the final drug product or converts during processing, storage, dissolution, or administration.

A separate solid-state patent could provide stronger protection if it claims:

Form 1 by analytical fingerprint.
A process for producing Form 1.
Form 1 with defined purity.
Form 1 in a pharmaceutical composition.
Form 1 with a particular particle-size distribution.
Conversion or crystallization conditions.

The supplied claims do not themselves claim the preparation of Form 1. They protect its therapeutic use.

What other patents are likely to affect elinzanetant?

The relevant patent estate should be divided into five layers.

Patent layer	Commercial function	Relevance to U.S. 10,195,205
Composition-of-matter patents	Protect the molecular structure	May expire earlier or later depending on priority date
Salt and polymorph patents	Protect Form 1 and other solid forms	Can extend practical barriers beyond the core molecule
Method-of-treatment patents	Protect hot-flush, menopausal, or vasomotor use	U.S. 10,195,205 is in this category
Formulation patents	Protect tablets, capsules, release profiles, or excipient systems	Could create separate infringement risks
Manufacturing patents	Protect synthesis, intermediates, purification, or crystallization	Can impede low-cost generic production

The central landscape question is not whether U.S. 10,195,205 covers the molecule generally. It does not. The question is whether other patents cover the molecule, Form 1, the finished dosage form, or the approved indication during the period in which a competitor seeks launch.

The most important search fields are the chemical structure, elinzanetant, BAY 3427080, NT-814, the full chemical name, formula A, crystalline anhydrate Form 1, and Bayer Pharma AG. Patent-family analysis should include U.S., PCT, EP, GB, DE, JP, CN, KR, and major commercial jurisdictions.

What litigation and settlement issues affect the patent?

The claim set creates several likely litigation questions:

Whether the patent is listed against the approved product.
Whether the approved label corresponds to the claimed hot-flush indication.
Whether a generic applicant files a Paragraph IV certification.
Whether Bayer asserts the patent within the statutory litigation window.
Whether the parties enter a launch-date settlement.
Whether the settlement is submitted to the Federal Trade Commission and Department of Justice under the Medicare Prescription Drug, Improvement, and Modernization Act.
Whether a later generic label carves out the protected indication.
Whether the Form 1 limitation can be proven in the generic product.

The claims supplied do not establish any filed infringement action, Paragraph IV notice, settlement, or final court ruling. Those matters are separate from the patent’s written scope and must be established from PACER, district-court dockets, FDA records, and FTC settlement disclosures.

How strong is the patent estate?

U.S. Patent 10,195,205 has moderate strategic value as a use patent and potentially high value if hot-flush treatment is the principal commercial indication for elinzanetant.

Strengths

The claims identify a single active ingredient with high chemical specificity.
The indication is commercially focused on vasomotor symptoms.
Claims 2 and 4 add a specific crystalline form.
Claims 3 and 4 directly address oral use, which is likely to match the commercial product.
A label carrying the protected indication could create substantial induced-infringement risk.

Limitations

The patent does not cover the molecule for every therapeutic use.
It does not claim composition of matter.
It does not claim a specific dose or regimen.
It does not expressly claim a tablet, capsule, excipient system, or release profile.
A generic may attempt an indication carve-out.
Validity may depend on the novelty and inventiveness of the treatment discovery and Form 1 disclosure.
The effective exclusivity period may be shorter than the nominal patent term if regulatory approval occurs late or if earlier composition patents expire first.

How does elinzanetant compare with fezolinetant?

Issue	Elinzanetant	Fezolinetant
Mechanism	Dual NK-1/NK-3 antagonist	Selective NK-3 receptor antagonist
Principal use	Menopausal vasomotor symptoms	Menopausal vasomotor symptoms
Patent focus in this analysis	Treatment method and Form 1	Separate composition, formulation, and use patent estate
Biosimilar exposure	None; small molecule	None; small molecule
Generic pathway	ANDA, not biosimilar application	ANDA, not biosimilar application
Competitive issue	Potentially broader neurokinin pathway coverage	Selective NK-3 mechanism and established approval position

Neither product faces biosimilar risk under the Biologics Price Competition and Innovation Act because both are small-molecule drugs. Competitive entry would proceed through an ANDA, subject to listed patents and regulatory exclusivity.

What generic launch scenarios exist?

Scenario 1: Launch after patent expiry

The generic launches after expiry of all blocking patents and regulatory exclusivities. This is the lowest litigation-risk pathway.

Scenario 2: Paragraph IV challenge

The applicant challenges U.S. 10,195,205 and any listed composition, formulation, or polymorph patents. A favorable judgment or settlement could permit an earlier launch.

Scenario 3: Label carve-out

The applicant removes hot-flush treatment from the label. This route is viable only if the remaining indications support approval and the label does not encourage the patented method.

Scenario 4: Non-Form 1 product

The applicant develops a different solid form. This may avoid claims 2 and 4, but it would not avoid claim 1 or claim 3 if the product contains elinzanetant and is labeled for oral hot-flush treatment.

Scenario 5: Alternative salt or formulation

A different pharmaceutically acceptable salt may remain within claims 1 and 3. Changing the salt does not necessarily avoid the broad active-ingredient claims.

Key Takeaways

U.S. Patent 10,195,205 is a method-of-treatment patent for hot flushes using elinzanetant.
Claim 1 is the broadest claim and covers the named compound and pharmaceutically acceptable salts without a route, dose, or formulation limitation.
Claim 3 specifically covers oral administration that alleviates hot-flush symptoms.
Claims 2 and 4 narrow protection to crystalline anhydrate Form 1.
The expected nominal expiry is in December 2035, subject to USPTO patent-term adjustment and any statutory patent-term extension.
The patent does not provide composition-of-matter protection for elinzanetant.
A generic could challenge the patent under Paragraph IV, seek a section viii label carve-out, or use a different solid form.
Elinzanetant is a small molecule and is exposed to ANDA-based generic competition rather than biosimilar competition.
The commercial strength of the patent depends heavily on Orange Book listing, the approved label, related composition and formulation patents, and the availability of an indication carve-out.
The supplied claim record establishes patent scope but does not establish a litigation outcome, settlement, Orange Book listing, or final generic launch date.

FAQs About U.S. Patent 10,195,205

Does U.S. Patent 10,195,205 cover all uses of elinzanetant?

No. It covers treatment of hot flushes with the specifically identified molecule or a pharmaceutically acceptable salt. It does not claim every disease, indication, formulation, or use of elinzanetant.

Can a generic avoid the patent by using a different salt?

Not necessarily. Claims 1 and 3 expressly cover pharmaceutically acceptable salts. A different salt would need to be evaluated against the claim language and the patent’s construction of the salt limitation.

Does a noncrystalline elinzanetant product avoid the patent?

It may avoid claims 2 and 4, which require Form 1. It would not automatically avoid claims 1 and 3, which do not contain the Form 1 limitation.

Is elinzanetant subject to biosimilar competition?

No. Elinzanetant is a small-molecule drug. Competitors would generally use the ANDA pathway rather than the biosimilar pathway.

What is the most important patent beyond U.S. 10,195,205?

The most important additional rights are likely the composition-of-matter patent, any Form 1 or polymorph patent, and formulation patents covering the commercial dosage form. Those rights determine whether an early generic launch remains possible after this use patent is challenged or expires.

References

United States Patent and Trademark Office. (2019). U.S. Patent No. 10,195,205, Treatment of hot flushes with NK-1/NK-3 receptor antagonists.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 355(j).
United States Patent and Trademark Office. (2024). Manual of Patent Examining Procedure, §§ 2710, 2711, and 2712.
U.S. Food and Drug Administration. (2016). Guidance for industry: 180-day exclusivity when multiple ANDA applicants are eligible for 180-day exclusivity.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Bayer Hlthcare	LYNKUET	elinzanetant	CAPSULE;ORAL	219469-001	Oct 24, 2025		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				TREATMENT OF MODERATE TO SEVERE VASOMOTOR SYMPTOMS DUE TO MENOPAUSE	⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	3297631	⤷ Start Trial	PA2026506	Lithuania	⤷ Start Trial
European Patent Office	3297631	⤷ Start Trial	C20260003	Finland	⤷ Start Trial
European Patent Office	3297631	⤷ Start Trial	CR 2026 00007	Denmark	⤷ Start Trial
European Patent Office	3297631	⤷ Start Trial	LUC50035	Luxembourg	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Summary for Patent: 10,195,205