US Patent 9,744,209: Vasopressin Formulation Claims, Exclusivity, Litigation Risk, and Patent Landscape

US Patent 9,744,209 protects a narrow method of treating hypotension with a vasopressin unit dosage form having defined concentration, pH, peptide-impurity content, administration rate, and, in some claims, a specified HPLC assay. The patent is not a broad composition patent covering all vasopressin products. Its commercial value depends on whether a competing product has the claimed impurity profile and whether the competitor’s label directs administration within the claimed dosing ranges.

The patent was granted September 26, 2017. Its projected expiration is June 30, 2035, subject to any patent-term adjustment or other term calculation shown in the official patent record.[1]

What does US Patent 9,744,209 cover?

The patent covers methods of increasing blood pressure in a hypotensive human by administering a vasopressin dosage form meeting several cumulative limitations.

Claim element	Independent claim 1 requirement
Therapeutic agent	Vasopressin or a pharmaceutically acceptable salt
Dosage form	Unit dosage form
Concentration	About 0.01 mg/mL to about 0.07 mg/mL
pH	3.7 to 3.9
Impurities	0.9% to 1.7%
Impurity identity	Impurities with approximately 85% to 100% sequence homology to SEQ ID NO. 1
Administration rate	About 0.01 to about 0.1 units per minute
Patient	Human who is hypotensive
Result	Increased blood pressure

Every limitation must be satisfied for literal infringement of claim 1. A product containing vasopressin at the claimed concentration does not infringe by itself. The formulation must also fall within the pH and impurity limitations, and the accused treatment must meet the patient and dosing requirements.

The claims are method claims. They do not independently claim:

Vasopressin as a chemical compound;
Every vasopressin injection;
A formulation having any pH;
A formulation with no defined impurity profile;
A manufacturing process for producing vasopressin;
A device used to administer vasopressin.

How broad is claim 1 of US 9,744,209?

Claim 1 is technically narrow but commercially relevant because it combines formulation and treatment limitations that may correspond closely to a marketed vasopressin injection.

Its principal narrowing features are the following:

The concentration range is limited to 0.01-0.07 mg/mL.
The pH must be 3.7-3.9.
The formulation must contain impurities at a total level of 0.9%-1.7%.
The impurities must have 85%-100% sequence homology to SEQ ID NO. 1.
The patient must be hypotensive.
The dosage rate must be 0.01-0.1 units per minute.

The impurity limitation is central. A generic manufacturer may use vasopressin with a different impurity profile, a different purification process, or a different pH while retaining the same active ingredient and therapeutic indication.

The phrase "about" creates ordinary claim-construction questions around the concentration and dosing boundaries. The pH range of 3.7-3.9 does not use "about" and is therefore more exact on its face. The impurity limitation also raises analytical questions concerning the reference sequence, testing method, measurement precision, and whether the 0.9%-1.7% range refers to the aggregate of qualifying impurities or a particular impurity population.

What do claims 2 through 8 protect?

Claims 2 through 8 narrow claim 1 by identifying particular peptide impurities and concentration ranges.

Claim	Additional limitation
2	SEQ ID NO. 2 at 0.1%-0.3%
3	SEQ ID NO. 3 at 0.1%
4	SEQ ID NO. 4 at 0.2%-0.4%
5	SEQ ID NO. 7 at 0.3%-0.6%
6	SEQ ID NO. 10 at 0.1%
7	SEQ ID NO. 2 and SEQ ID NO. 4 at the specified levels
8	SEQ ID NO. 2, 3, 4, 7, and 10 at the specified levels

Claims 7 and 8 are combination claims. They may be more difficult to read on a competing product because the competitor must contain the specified group of impurities at the claimed levels. They may also be more difficult to invalidate for lack of written description or enablement if the patent specification provides detailed analytical support for those exact impurity combinations.

Claim 3 is unusually rigid because it recites SEQ ID NO. 3 at "0.1%" without a stated range or tolerance. That language may create disputes over analytical precision and whether a measured value of 0.09% or 0.11% falls within the claim.

The sequence definitions are essential. The supplied claim text does not identify the actual amino-acid sequences for SEQ ID NOS. 1, 2, 3, 4, 7, or 10. Without those sequences, an independent determination of sequence identity, sequence homology, or literal coverage by a competitor’s peptide profile cannot be completed.

What does claim 11 protect?

Claim 11 adds a specific HPLC-based impurity-identification procedure. The method requires:

A chromatography column containing adsorbent particles;
Phosphate buffer at pH 3 as the first mobile phase;
A 50:50 acetonitrile-water second mobile phase;
A 55-minute run;
A flow rate of 1 mL/min for each mobile phase;
Gradient elution;
UV detection;
Identification by retention time relative to a standard; and
Quantification by integration of the relevant UV peak.

Claim 11 does not merely require that impurities exist. It specifies how the impurities are determined. That limitation may be important in litigation because the patent holder would need to establish that the accused dosage form was tested under the claimed or legally equivalent procedure.

The claim can create proof issues in both directions. A patent owner may argue that the accused product meets the limitation when tested using the prescribed assay. A defendant may argue that a different analytical method, column, standard, detector response, or integration protocol produces a different impurity result.

What formulations are protected by claims 12 and 13?

Claim 12 adds sodium acetate. Claim 13 adds a pH-adjusting agent.

These claims strengthen the patent’s coverage of a conventional injectable formulation architecture, but they remain dependent on all limitations of claim 1. Sodium acetate alone is not enough to trigger claim 12. The formulation must also meet the vasopressin concentration, pH, impurity, and administration requirements of the parent claim.

Claim 13 is broader than claim 12 because it does not identify a particular pH-adjusting agent. Potential agents could include acids or bases used to establish or maintain the claimed pH, subject to claim construction and the specification.

What is the Orange Book status of US 9,744,209?

The relevant FDA-listed product is Vasostrict, a vasopressin injection product approved for increasing blood pressure in adults with vasodilatory shock who remain hypotensive despite fluids and catecholamines.[2]

US 9,744,209 is associated with the Vasostrict patent estate and has been treated as a product patent relevant to abbreviated new drug application, or ANDA, challenges. The precise current Orange Book listing, delisting status, and any associated use code must be confirmed against the current FDA Orange Book patent-and-exclusivity data.[3]

The patent’s claim structure is important for regulatory strategy. Because the claims are method-of-use claims, an ANDA applicant may consider:

A Paragraph IV certification challenging validity, enforceability, or infringement;
A section VIII statement carving out a patented indication, if the patented method can be omitted from labeling;
A non-infringement position based on formulation pH, impurity profile, concentration, or dosing instructions; or
A formulation or manufacturing change designed to avoid the asserted limitations.

A section VIII strategy is less effective if the patented method is coextensive with the approved indication or if the proposed label still instructs use for hypotension associated with vasodilatory shock.

When does US 9,744,209 lose exclusivity?

The projected patent expiration date is June 30, 2035, based on the patent-family filing chronology associated with the patent.[1] The practical loss of market exclusivity may occur earlier if:

A court invalidates the patent;
A court finds non-infringement;
An ANDA applicant wins a Paragraph IV case;
The patent is disclaimed or delisted;
A settlement permits an earlier generic launch; or
A competitor designs around the claim limitations.

FDA regulatory exclusivity is separate from patent exclusivity. Vasostrict’s approval-based exclusivity period does not extend the patent term. The principal remaining barrier represented by US 9,744,209 is patent-based rather than new-drug exclusivity-based.[2][3]

Event	Date or status
US patent grant	September 26, 2017
Projected patent expiration	June 30, 2035
Product associated with the patent estate	Vasostrict vasopressin injection
Therapeutic use	Blood-pressure increase in vasodilatory shock
Regulatory pathway for challengers	ANDA Paragraph IV, section VIII, or non-infringement strategy
Biosimilar pathway	Not applicable to vasopressin, a synthetic peptide drug rather than a biologic licensed through the biosimilar pathway

Which companies are challenging Vasostrict patents?

The competitive threat comes primarily from generic injectable-drug manufacturers pursuing ANDAs for vasopressin injection. The relevant challenger set may include companies that have filed ANDAs or launched generic vasopressin products, but the identity of each active Paragraph IV challenger and the status of each case must be determined from current FDA and PACER records.

A generic product can avoid direct infringement if its formulation or labeling falls outside the claim. The highest-risk scenario for the patent holder is a generic that:

Uses the same or substantially similar vasopressin concentration;
Has pH of 3.7-3.9;
Contains the claimed peptide impurities within the listed ranges;
Carries a label for hypotension associated with vasodilatory shock; and
Directs administration at 0.01-0.1 units per minute.

A generic that uses a different pH or impurity specification may retain therapeutic substitutability while reducing literal infringement risk.

What patent litigation affects US 9,744,209?

The principal litigation question is whether an ANDA product would infringe the method claims when used according to its proposed labeling. A patent owner would likely focus on:

The product’s certificate of analysis and impurity profile.
The pH of the commercial dosage form.
The proposed concentration and container configuration.
The dosing instructions in the ANDA label.
Whether the label includes vasodilatory shock.
Whether the product is reasonably expected to be used in the claimed manner.

A defendant would likely challenge the claims through:

Non-infringement based on concentration or pH;
Non-infringement based on impurity identity or percentage;
Non-infringement based on dosing rate;
Invalidity for indefiniteness;
Lack of written description or enablement;
Obviousness based on known vasopressin formulations and impurity-control methods; and
Limits on induced infringement where the label does not direct the claimed method.

Settlement terms, launch dates, and any covenant-not-to-sue provisions are material commercial facts. They should not be inferred from the patent grant or FDA approval alone.

How strong is the patent estate for vasopressin?

US 9,744,209 has moderate claim specificity and potentially meaningful commercial leverage.

Strengths

It targets a marketed injectable product and a clinically relevant indication.
It combines formulation and method-of-use limitations.
The impurity profile may be difficult to avoid without changing the manufacturing or purification process.
Dependent claims identify multiple impurity combinations and provide fallback positions.
Claim 11 provides a detailed analytical framework for proving impurity content.

Weaknesses

The claims are narrow and require multiple elements simultaneously.
The sequence limitations cannot be evaluated without the referenced sequences.
Impurity percentages may vary by lot, assay, storage condition, and analytical integration method.
The pH range is narrow and may be designed around.
A generic may challenge whether the claim adequately describes the full 85%-100% homology scope.
Method claims depend partly on physician or institutional administration practices.

The patent is stronger against a copycat formulation than against a technically differentiated generic.

What generic launch scenarios exist?

Scenario	Likely patent impact
Same concentration, pH, impurities, indication, and dosing	Highest infringement exposure
Same active ingredient but pH outside 3.7-3.9	Stronger non-infringement position
Different impurity profile	Potentially avoids claims 1-8
Label omits vasodilatory shock	May support section VIII or non-infringement strategy
Same formulation but dosing instructions outside claimed range	May reduce method-claim exposure
Litigation settlement	Launch date depends on negotiated entry terms
Patent invalidation	Earliest unrestricted generic entry, subject to other patents and FDA requirements

How does US 9,744,209 compare with biosimilar and generic barriers?

Vasopressin is not a conventional biologic subject to the Public Health Service Act biosimilar pathway. The principal pathway is an ANDA for a generic drug product, with pharmaceutical equivalence, bioequivalence, manufacturing, labeling, and patent-certification requirements.

The key barrier is therefore not biosimilar interchangeability or biologic manufacturing complexity. It is the combination of:

Peptide impurity control;
Injectable-product quality requirements;
Formulation similarity;
Analytical reproducibility;
Patent certification; and
Potential method-of-use litigation.

Manufacturing know-how may have commercial value even where it does not independently create patent protection. A supplier that can consistently produce vasopressin outside the claimed impurity profile may have a stronger design-around position.

Key Takeaways

US 9,744,209 is a narrow method patent directed to vasopressin treatment of hypotension.
Claim 1 requires a specific concentration, pH, impurity range, patient condition, and infusion rate.
Claims 2-8 add defined peptide impurities and concentration ranges.
Claim 11 limits impurity determination through a detailed HPLC and UV assay.
Claims 12 and 13 add sodium acetate and pH-adjusting-agent limitations.
The patent is relevant to Vasostrict and generic vasopressin injection competition.
The projected expiration date is June 30, 2035.
The highest generic risk arises where the proposed product and label reproduce the claimed formulation and dosing conditions.
A differentiated pH, impurity profile, concentration, or label may reduce infringement exposure.
The actual sequence definitions and current FDA litigation records are necessary for a complete claim chart against a particular product.

FAQs

Does US 9,744,209 claim all vasopressin injections?

No. It claims a specific treatment method using a dosage form with defined concentration, pH, impurity content, and administration parameters.

Can a generic avoid US 9,744,209 by changing the vasopressin concentration?

Potentially. A concentration outside the claimed range may avoid literal infringement, but the complete product and labeling must be evaluated against every asserted claim and the doctrine of equivalents.

Are the impurity claims product claims or method claims?

They are limitations in method claims. The claims require administration of a unit dosage form containing the specified impurity profile.

Does the patent cover vasopressin use in septic shock?

The supplied claims expressly identify vasodilatory shock in dependent claim 9. Whether septic shock falls within that term depends on the facts, label language, and claim construction.

Is a vasopressin generic a biosimilar?

No. Vasopressin products are generally pursued through the generic-drug framework rather than the biosimilar pathway.

References

United States Patent and Trademark Office. (2017). US Patent No. 9,744,209, Vasopressin compositions and methods of use thereof.
U.S. Food and Drug Administration. (n.d.). Vasostrict prescribing information.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Ph Health	VASOSTRICT	vasopressin	SOLUTION;INTRAVENOUS	204485-001	Apr 17, 2014	AP	RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				TO INCREASE BLOOD PRESSURE IN ADULTS WITH VASODILATORY SHOCK (E.G., POST-CARDIOTOMY OR SEPSIS) WHO REMAIN HYPOTENSIVE DESPITE FLUIDS AND CATECHOLAMINES	⤷ Start Trial
Ph Health	VASOSTRICT	vasopressin	SOLUTION;INTRAVENOUS	204485-002	Dec 17, 2016	AP	RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				TO INCREASE BLOOD PRESSURE IN ADULTS WITH VASODILATORY SHOCK (E.G., POST-CARDIOTOMY OR SEPSIS) WHO REMAIN HYPOTENSIVE DESPITE FLUIDS AND CATECHOLAMINES	⤷ 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

Details for Patent: 9,744,209

Which drugs does patent 9,744,209 protect, and when does it expire?

Summary for Patent: 9,744,209