United States Patent 10,028,965: Scope, Claims, Expiration, and Dexycu Patent Landscape

U.S. Patent No. 10,028,965 protects a post-cataract-surgery treatment method using a single 4-6 μL intraocular dose containing approximately 517 μg of dexamethasone in acetyl triethyl citrate. The patent is directed to the use of a sustained-release formulation, not to dexamethasone generally. Its strongest commercial relevance is to Dexycu, an intraocular dexamethasone suspension marketed by EyePoint Pharmaceuticals.

The patent’s core barriers are cumulative: the product must contain the specified dexamethasone amount and vehicle, be administered by intraocular injection after cataract surgery, use a single small-volume dose, and satisfy specified in vitro release or clinical-response limitations. The stated patent expiration date is February 1, 2033, before any applicable patent-term adjustment or extension analysis.

What does U.S. Patent 10,028,965 cover?

U.S. Patent 10,028,965 covers a method of treating ocular inflammation following cataract surgery by injecting a single dose of a dexamethasone formulation into the eye. The formulation contains approximately 517 μg of dexamethasone in triethyl acetyl citrate and releases dexamethasone for at least three days under an infinite-sink saline-release test.[1]

The patent does not claim:

Dexamethasone as an active pharmaceutical ingredient in the abstract.
Every ophthalmic dexamethasone formulation.
Every treatment of postoperative eye inflammation.
Topical dexamethasone drops.
Dexamethasone implants that do not meet the claimed formulation and administration limitations.

The claims are method-of-treatment claims with formulation, dose, route, release, and clinical-response restrictions.

What is the independent claim?

Claim 1 requires all of the following:

Cataract surgery has been completed.
The eye is treated for postoperative inflammation.
The treatment uses an injection into the eye.
The administration is a single dose.
The dose volume is approximately 4-6 μL.
The dose contains approximately 517 μg of dexamethasone.
The dexamethasone is formulated in triethyl acetyl citrate.
The formulation releases dexamethasone for at least three days in saline under infinite-sink conditions.

A product or treatment that omits any one of these limitations may avoid literal infringement of claim 1, although dependent claims and other patent-family claims must also be reviewed.

How do the dependent claims narrow the patent?

Claim	Additional limitation	Practical significance
2	Dose volume of about 5 μL	Targets the commercial dose volume most closely associated with Dexycu
3	Release for at least seven days	Requires a longer sustained-release profile
4	Release for at least seven and no more than 35 days	Defines a bounded release period
5	At least 30% of dexamethasone remains after three days	Adds a formulation-retention test
6	Anterior chamber cell count below 3 within eight days	Adds a clinical efficacy limitation
7	Anterior chamber cell count below 2 within 30 days	Adds a stricter clinical-response limitation
8	Injection behind the iris	Covers a posterior location within the anterior segment
9	Injection into the anterior segment	Broader anatomical route than claim 10
10	Injection into the anterior chamber	Directly covers intracameral administration
11	Claim 8 plus a dose volume of about 5 μL	Combines behind-the-iris administration with the commercial volume

Claim 1 is the principal infringement risk because it establishes the broadest claimed combination. Claims 2-11 create narrower positions that may be useful against design-around products using the same formulation but different injection locations, release profiles, or clinical dosing protocols.

What formulation is protected by U.S. Patent 10,028,965?

The formulation limitation is central. The claims require approximately 517 μg of dexamethasone in triethyl acetyl citrate. The vehicle is commonly identified in product materials as acetyl triethyl citrate. The claimed composition is associated with a long-acting intraocular suspension designed to deliver dexamethasone after a single administration.

The phrase “consisting essentially of” is narrower than “comprising” but broader than “consisting of.” It generally permits additional ingredients that do not materially alter the basic and novel characteristics of the formulation. A competing product could face infringement exposure even if it contains additional excipients, provided the claimed dexamethasone, vehicle, dose, and release characteristics remain present.

The formulation claims are indirect rather than standalone composition claims. Infringement generally requires use of the formulation in the claimed postoperative cataract-surgery treatment method.

What release characteristics are required?

The patent uses an in vitro release test conducted in saline under infinite-sink conditions. The key thresholds are:

At least three days of dexamethasone release under claim 1.
At least seven days under claim 3.
Seven to 35 days under claim 4.
At least 30% of dexamethasone retained after three days under claim 5.

These limitations create technical questions in any infringement dispute. The parties would likely contest:

The precise composition of the saline medium.
Whether the test satisfies infinite-sink conditions.
Agitation, temperature, sampling, and analytical methodology.
Whether “releases for at least” refers to measurable release or continued release above a specified quantitation threshold.
Whether the formulation must meet the release profile before administration or after intraocular placement.

The release limitations can strengthen validity by narrowing the claims, but they can also complicate enforcement because the result depends on laboratory testing and claim construction.

What are the strongest infringement positions under the patent?

The strongest position targets a product that reproduces the commercial profile:

Approximately 5 μL injected after cataract surgery.
Approximately 517 μg dexamethasone.
Acetyl triethyl citrate as the vehicle.
Intracameral or anterior-segment administration.
Sustained release for at least seven days.
Clinical reduction in anterior chamber cells within the claimed periods.

Claims 2, 3, 7, 10, and 11 are particularly relevant to a Dexycu-equivalent product administered into the anterior chamber. Claim 8 may apply where the surgeon places the dose behind the iris rather than directly into the anterior chamber.

A generic that uses the same formulation but changes the labeled volume from 5 μL to 6 μL could remain within claim 1 because claim 1 covers approximately 4-6 μL. A volume change alone therefore may not provide a reliable design-around.

A product containing a materially different vehicle, a different dexamethasone load, or a noninjectable delivery system would have a stronger noninfringement position under this patent. It could still face other patents covering the formulation, manufacturing process, delivery system, or method of use.

When does U.S. Patent 10,028,965 lose exclusivity?

The listed expiration date is February 1, 2033.[2] That date corresponds to the patent family’s earliest effective nonprovisional priority date and the standard 20-year patent term. The commercial exclusivity analysis must also account for:

Patent-term adjustment shown in the USPTO record.
Any patent-term extension under 35 U.S.C. § 156.
Continuation patents with later expiration dates.
Other Orange Book-listed patents covering Dexycu.
Regulatory exclusivity that may expire before or after the patent estate.

Patent expiration does not itself authorize immediate market entry if another unexpired patent covers the same product or use. A generic applicant must evaluate the entire Orange Book listing and any relevant non-Orange-Book patent rights.

What is the Orange Book status of U.S. Patent 10,028,965?

Dexycu is approved under FDA NDA 208742. FDA approved Dexycu on February 12, 2018, for the treatment of postoperative inflammation following cataract surgery.[3]

U.S. Patent 10,028,965 has been associated with the Dexycu patent estate and is relevant to the product’s Orange Book protection. The Orange Book analysis should be conducted at the product level because the relevant question is not only whether Patent 10,028,965 is listed, but whether additional patents are listed for the same NDA.

For a generic applicant, the Orange Book consequences are:

A Paragraph IV certification may trigger a patent-holder notification.
Filing an infringement action within the statutory period can trigger a 30-month stay.
A Paragraph III certification would defer approval until patent expiration.
A Section viii statement may be available only if the generic labeling omits the patented use and FDA accepts the omission.

Because the patent claims postoperative cataract-surgery treatment, a generic seeking the same labeled indication would face a direct method-of-use issue. A carve-out strategy would be difficult if the patented use is the principal approved indication.

Are there Paragraph IV challenges to Dexycu?

Publicly available patent records and FDA product information identify the relevant Dexycu patent estate, but no publicly established Paragraph IV litigation outcome is identified for U.S. Patent 10,028,965 in the materials reviewed here.

The commercial risk remains substantial even without a reported final judgment. A future ANDA filer could challenge the patent on:

Lack of written description for the exact dose and release profile.
Lack of enablement across the full 4-6 μL and 3-35 day ranges.
Obviousness based on prior intraocular dexamethasone formulations and sustained-release systems.
Indefiniteness of “about,” “consisting essentially of,” and the release-test language.
Noninfringement based on formulation composition, injection site, or release behavior.

The patent holder could counter with literal infringement and, depending on the facts, infringement under the doctrine of equivalents. The most defensible invalidity attack would likely focus on obviousness and the predictability of achieving the claimed dose, vehicle, and release profile from earlier sustained-release ophthalmic technologies.

How strong is the patent estate for Dexycu?

The estate is commercially meaningful because the patent claims align closely with the product’s dosing and administration instructions. Its strength is higher against a direct Dexycu copy than against alternative postoperative anti-inflammatory products.

Factor	Assessment
Claim-product alignment	Strong
Claim type	Method of treatment
Formulation specificity	High
Dose specificity	High, but “about” broadens the range
Route specificity	Strong for intracameral and anterior-segment injection
Release testing	Useful but technically contestable
Clinical limitations	Narrower and potentially harder to prove
Small-molecule generic exposure	Material
Biosimilar exposure	Not applicable
Design-around potential	Moderate
Expiration timing	2033 nominal patent expiry

The patent is stronger when the accused product uses the same vehicle and dose. It is weaker against products that deliver dexamethasone through a different matrix, implant, injectable depot, or topical regimen.

What other patents and IP rights matter?

The relevant landscape extends beyond Patent 10,028,965.

Formulation patents

Other patents in the Dexycu family may claim:

Dexamethasone suspensions.
Acetyl triethyl citrate-based depot formulations.
Particle-size or suspension characteristics.
Drug-release profiles.
Ophthalmic administration methods.
Postoperative inflammation treatment.

Continuation and divisional applications can produce claims with different statutory categories and later expiration dates. A freedom-to-operate review should therefore map the entire U.S. family rather than rely on a single patent.

Method-of-use patents

Method claims may cover:

Treatment after cataract surgery.
Intracameral administration.
Injection behind the iris.
Reduction of anterior chamber cells.
Reduced need for topical corticosteroid drops.
Treatment of postoperative inflammation for a defined duration.

These claims can remain relevant even if a competitor avoids the exact formulation in Patent 10,028,965.

Manufacturing and trade-secret barriers

Commercial replication may require more than copying the active ingredient and vehicle. Relevant barriers include:

Control of dexamethasone particle size.
Suspension uniformity.
Sterility and aseptic filling.
Syringe or vial compatibility.
Sedimentation control.
Dose withdrawal accuracy at approximately 5 μL.
Release reproducibility after intraocular injection.

Manufacturing know-how may be protected through process patents, confidential information, or regulatory CMC data even where a competitor avoids literal infringement of the issued claims.

Does biosimilar risk apply to Dexycu?

No. Dexycu contains dexamethasone, a chemically defined small-molecule corticosteroid. The principal competitive pathway is an ANDA for a generic drug, not a biosimilar application under the Public Health Service Act.

The relevant competitive risks are:

Paragraph IV ANDA litigation.
A noninfringing alternative dexamethasone formulation.
Compounded ophthalmic products, subject to applicable FDA and state-law restrictions.
Other postoperative corticosteroid products.
Combination anti-inflammatory and antibiotic regimens.
Topical corticosteroid products used after cataract surgery.

How does Dexycu compare with competing postoperative corticosteroids?

Product category	Administration	Sustained release	Patent risk relative to U.S. 10,028,965
Dexycu	Single intraocular injection	Yes	Direct target
Topical dexamethasone drops	Patient-administered topical dosing	No or limited	Generally outside claim scope
Dexamethasone intracanalicular insert	Insert placed in lacrimal canaliculus	Yes	Different delivery route; other patents matter
Difluprednate ophthalmic emulsion	Topical drops	No	Outside the claimed injection method
Loteprednol ophthalmic suspension or gel	Topical	No or limited	Outside the claimed formulation and route
Triamcinolone intraocular products	Intraocular injection	Variable	Different active ingredient

Dexycu’s commercial differentiation is the single-dose intraocular administration, which reduces reliance on patient adherence to postoperative drops. That same product characteristic creates close overlap with the claims of Patent 10,028,965.

What is the commercial exposure from this patent?

The patent’s commercial exposure is tied to the U.S. market for cataract surgery, where postoperative inflammation treatment is routine. A generic entrant could affect:

Dexycu net sales.
Hospital and ambulatory surgery center contracting.
Physician preference for single-dose intraocular therapy.
Reimbursement and bundled cataract-procedure economics.
Licensing value of EyePoint’s sustained-release platform.

The highest-value scenario for the patent holder is a direct generic substitution using the same dose, vehicle, and intracameral route. A lower-risk competitor would use a different delivery system or rely on topical administration, although those products may compete clinically without infringing this patent.

Key Takeaways

U.S. Patent 10,028,965 is a method patent closely aligned with Dexycu.
Claim 1 requires a single 4-6 μL intraocular dose containing approximately 517 μg dexamethasone in triethyl acetyl citrate.
Claims 2-11 add a 5 μL dose, release duration, drug-retention, cell-count, and anatomical injection limitations.
The patent is most important against a direct Dexycu generic using the same formulation and intracameral route.
The stated patent expiration date is February 1, 2033.
Dexycu was approved under NDA 208742 on February 12, 2018.
Biosimilar law does not apply; ANDA and Paragraph IV litigation are the principal generic-entry mechanisms.
Alternative vehicles, delivery systems, topical products, and different active ingredients offer the clearest design-around paths.
The full patent-family and Orange Book analysis is required before determining launch freedom.

FAQs About U.S. Patent 10,028,965

Can a generic avoid U.S. Patent 10,028,965 by using a 10 μL dose?

A 10 μL dose would fall outside the literal 4-6 μL limitation in claim 1, but the generic must still assess other patents and potential doctrine-of-equivalents arguments.

Does the patent cover topical dexamethasone drops after cataract surgery?

No. The asserted claims require administration by injecting the formulation into the eye. Topical drops do not satisfy that route limitation.

Does changing acetyl triethyl citrate to another excipient avoid the patent?

Potentially. A materially different vehicle may avoid the formulation limitation, but the substitute formulation could be covered by other formulation or process patents.

Can a generic omit the postoperative inflammation indication from its label?

A Section viii labeling carve-out may be possible only if the omitted indication can be removed while maintaining an FDA-approved, noninfringing use. The feasibility depends on the Orange Book-listed use code and the proposed labeling.

Is Patent 10,028,965 a composition-of-matter patent?

No. Its issued claims are methods of treating postoperative ocular inflammation using a specified dexamethasone formulation, dose, route, and release profile.

References

United States Patent and Trademark Office. (2018). U.S. Patent No. 10,028,965, Dexamethasone compositions and methods of use thereof.
United States Patent and Trademark Office. (n.d.). Patent term information for U.S. Patent No. 10,028,965.
U.S. Food and Drug Administration. (2018). Dexycu prescribing information and approval history, NDA 208742.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
EyePoint Pharmaceuticals, Inc. (2024). Annual report on Form 10-K. U.S. Securities and Exchange Commission.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Eyepoint Pharms	DEXYCU KIT	dexamethasone	SUSPENSION;INTRAOCULAR	208912-001	Feb 9, 2018		DISCN	Yes	No	10,028,965	⤷ Start Trial				TREATMENT OF POSTOPERATIVE INFLAMMATION	⤷ 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
Australia	2014268434	⤷ Start Trial
Canada	2913336	⤷ Start Trial
China	105407896	⤷ Start Trial
China	110339153	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 10,028,965

Which drugs does patent 10,028,965 protect, and when does it expire?

Summary for Patent: 10,028,965