Details for Patent: 11,273,171

Which drugs does patent 11,273,171 protect, and when does it expire?

Patent 11,273,171 protects IZERVAY and is included in one NDA.

This patent has forty-six patent family members in twenty-four countries.

Summary for Patent: 11,273,171

Title:	Methods for treating or preventing ophthalmological conditions
Abstract:	The present invention relates to methods for treating and preventing ophthalmological disease and disorders, comprising administering Antagonist A or another pharmaceutically acceptable salt thereof, optionally in combination with another treatment, to a subject in need thereof. The present invention also relates to methods for treating and preventing ophthalmological disease and disorders, comprising administering an anti-C5 agent (e.g., ARC1905), optionally in combination with another treatment, to a subject in need thereof.
Inventor(s):	Samir Patel, Richard Everett, Douglas Brooks, Shane Xinxin Tian
Assignee:	Astellas US LLC
Application Number:	US17/346,556
Patent Claim Types: see list of patent claims	Use;

U.S. Patent 11,273,171: Claim Scope, Geographic Atrophy Exclusivity and Patent Landscape

U.S. Patent No. 11,273,171 protects a treatment regimen for geographic atrophy using approximately 2 mg per eye of a pegylated anti-C5 aptamer administered by intravitreal injection. The claimed aptamer corresponds to avacincaptad pegol, marketed as Izervay by Iveric Bio, an Astellas company. The patent focuses on treatment method, dosing frequency, PEG architecture, aptamer chemistry, lesion-growth reduction and imaging-based assessment.

The broadest independent claims require all of the following:

1. Geographic atrophy in a human subject.
2. Intravitreal administration.
3. Approximately 2 mg per eye.
4. A specific chemically modified aptamer sequence, SEQ ID NO:26.
5. PEG conjugation.
6. Biweekly, monthly or quarterly administration.
7. Reduction in geographic-atrophy lesion growth.

Claims 18 and 19 narrow the method further by requiring a branched PEG of more than approximately 10 kDa and lesion-growth reduction of at least 30% or 40%, respectively. (U.S. Patent No. 11,273,171, 2022).

What drug and technology does U.S. Patent 11,273,171 cover?

The claimed product is a PEGylated anti-C5 aptamer. The sequence uses a combination of:

Structural element	Claimed characteristic
Aptamer	SEQ ID NO:26
Cytidine and uridine modifications	2′-fluoro nucleotides
Guanosine and adenosine modifications	2′-O-methyl nucleotides
Remaining nucleotides	2′-hydroxyl nucleotides
3′ terminus	Inverted deoxythymidine, identified as 3T
PEG attachment	Via a linker
Preferred PEG	Branched PEG
Preferred PEG size	About 40 kDa
Administration	Intravitreal injection
Dose	About 2 mg per eye
Disease	Geographic atrophy
Target outcome	Reduced lesion growth

The sequence and chemical modifications are important claim limitations. A competing product directed against C5 would not necessarily infringe this patent unless it uses the claimed sequence or a legally equivalent sequence under the relevant claim construction.

The product associated with this technology is avacincaptad pegol, also known as Zimura during development and Izervay after FDA approval. Avacincaptad pegol inhibits complement component C5, blocking formation of terminal complement pathway products including C5a and C5b-9.

How broad are the independent claims?

Claim 1 is a method claim with multiple cumulative limitations. It is broad as to dosing interval because it covers biweekly, monthly and quarterly administration. It is narrow as to the active agent because it identifies a particular modified aptamer sequence.

Claim 18 is an independent method claim that adds:

• Branched PEG;
• PEG molecular weight greater than approximately 10 kDa; and
• At least 30% reduction in lesion growth.

Claim 19 adds the same PEG limitations but requires at least 40% lesion-growth reduction.

The practical scope is therefore concentrated around the commercial avacincaptad pegol product rather than the full universe of complement inhibitors. A product using pegcetacoplan, a C3 inhibitor, would not satisfy the claimed aptamer-sequence limitation. A product using a different C5 antibody or peptide also would not literally satisfy the sequence limitation.

What limitations create the principal infringement risk?

The principal risk factors are:

1. Active ingredient identity. The accused product must contain the claimed aptamer or an equivalent.
2. Dose. Administration must be approximately 2 mg per eye.
3. Route. The claim requires intravitreal injection.
4. Disease. The use must treat geographic atrophy.
5. Administration interval. The claim covers biweekly, monthly and quarterly schedules.
6. PEG configuration. Claims 18 and 19 require a branched PEG above approximately 10 kDa.
7. Clinical outcome. Claims 18 and 19 require at least 30% or 40% lesion-growth reduction.

A competitor could avoid literal infringement by changing the active sequence, eliminating the specified PEG structure, using a materially different molecular weight, or pursuing a different clinical indication. Those changes could still face doctrine-of-equivalents arguments, but the risk would depend on prosecution history and the precise amendments made during examination.

What do the dependent claims add?

Claims 2 through 7 develop the PEG architecture.

Claim	Added limitation
2	PEGylated moiety conjugated through a linker
3	PEG attached to the 5′ end
4	Branched PEG
5	PEG molecular weight greater than approximately 10 kDa
6	PEG molecular weight of approximately 40 kDa
7	Specific PEG structure shown in the patent

Claims 8 and 13 through 16 add efficacy thresholds ranging from at least 10% to at least 50% reduction in lesion growth. Claim 17 specifies autofluorescence imaging or optical coherence tomography as the assessment method.

Claims 9 through 12 address administration schedules:

• Monthly dosing;
• Monthly dosing for three injections followed by extended intervals;
• Bimonthly dosing;
• Quarterly dosing.

The claims use “biweekly” and “bimonthly,” which can create interpretation issues because both terms may be used inconsistently to mean every two weeks or every two months. Patent litigation would likely examine the specification, prosecution record and technical context to determine the intended meaning.

What claim-drafting inconsistencies affect enforceability?

Several supplied claims contain drafting inconsistencies that could affect interpretation.

First, claims 8 through 16 refer to an “anti-C5 agent,” although claim 1 expressly identifies a PEGylated aptamer. The inconsistency may be a clerical carryover from broader anti-C5 disclosure or an earlier claim set. Courts generally construe claims in light of the specification, but an inconsistent term can create indefiniteness, written-description or scope arguments.

Second, claims 9 through 12 refer to “the anti-C5 agent” rather than the “pegylated aptamer.” The patent owner would likely argue that the term refers to the claimed aptamer. An accused infringer could argue that the wording introduces ambiguity.

Third, claims 18 and 19 appear to repeat the core limitations of claim 1 as independent claims while adding additional restrictions. Their value is redundancy and fallback protection. If a court invalidated or narrowed a limitation in claim 1, claims 18 and 19 could preserve narrower coverage if the added efficacy and PEG limitations are adequately supported.

Fourth, claim 7 depends on claim 1 but introduces a specific PEG structure that is not visible in the supplied text. Its scope depends on the structural drawing and the patent specification.

What is the FDA status of the patented product?

The FDA approved Izervay (avacincaptad pegol intravitreal solution) in August 2023 for the treatment of geographic atrophy secondary to age-related macular degeneration. The approved dose is 2 mg administered by intravitreal injection approximately every 28 days. (U.S. Food and Drug Administration, 2023).

The commercial label does not necessarily practice every patent claim. In particular:

• The approved regimen is monthly, which falls within claim 1 and claim 9.
• The approved dose corresponds to the approximately 2 mg-per-eye limitation.
• The product is administered by intravitreal injection.
• The indication is geographic atrophy.
• The label does not establish that every patient achieves the 30%, 40% or 50% lesion-growth thresholds required by claims 13 through 16, 18 and 19.

The claims use a result-based limitation. Infringement analysis would therefore consider whether the claimed reduction is an inherent or intended result of administering the product, and whether the threshold is measured using the specified methods or equivalent methods.

What is the Orange Book status of U.S. Patent 11,273,171?

U.S. Patent 11,273,171 is a drug-related method patent associated with avacincaptad pegol. Its practical regulatory significance depends on whether and when it is listed in the FDA Orange Book for Izervay.

An Orange Book listing can support a Paragraph IV certification by an ANDA applicant. The listing does not itself establish validity or enforceability. It creates a statutory pathway for patent litigation and may trigger a 30-month stay if the reference-drug sponsor or patent owner files suit within the statutory period. (U.S. Food and Drug Administration, 2024).

The patent number alone does not establish:

• The current Orange Book listing status;
• The date of any listing;
• Whether the listed patent is identified as a method-of-use patent;
• The specific use code;
• Whether the patent remains listed after any regulatory or litigation event.

For business planning, the relevant question is whether the patent appears in the current FDA Orange Book under Izervay and which use code accompanies it. A method-of-use listing would ordinarily be more vulnerable to a “section viii” statement by an ANDA applicant seeking to omit the patented use, but that strategy would not work if the proposed label still encourages the patented geographic-atrophy use.

When does U.S. Patent 11,273,171 lose exclusivity?

The patent’s expiration date cannot be established from the claim text alone. The controlling date depends on:

• The earliest effective nonprovisional priority date;
• Patent-term-adjustment days;
• Any terminal disclaimer;
• Patent-term extension;
• Patent-term disclaimer or other prosecution-specific adjustment.

The issue date, March 15, 2022, is not the expiration date. A U.S. utility patent generally receives a term measured from the earliest effective nonprovisional filing date, subject to statutory adjustments. The relevant term must be confirmed from the USPTO patent record and any terminal-disclaimer information.

Separately, Izervay’s regulatory exclusivity is distinct from patent exclusivity. FDA approval-based exclusivity may expire before the relevant patents. Patent expiry may also occur after generic or follow-on applicants have filed challenges.

How strong is the patent estate for avacincaptad pegol?

The estate is strongest where a competitor seeks to copy the commercial product and its dosing regimen. The patent combines product-specific chemical identity with a disease-specific use and commercially relevant dosing.

Estate characteristic	Strength assessment
Specific aptamer sequence	Strong against identical active-ingredient copies
2 mg per-eye dose	Strong against label-matching products
Intravitreal route	Strong for directly substitutable products
Monthly dosing	Strong because it matches the FDA regimen
Quarterly dosing	Broader schedule coverage, but less aligned with the current label
Branched PEG	Stronger fallback limitation
Approximately 40 kDa PEG	Narrower but commercially relevant
Lesion-growth thresholds	Potentially difficult to prove on a patient-by-patient basis
Imaging limitation	Provides a defined measurement pathway
Anti-C5 terminology	Creates construction and clarity issues

The patent is less effective against a different molecular format. A C5 antibody, C5 peptide inhibitor, C3 inhibitor or alternative RNA construct would generally require a separate infringement theory.

How does Izervay compare with Syfovre?

Izervay and Syfovre are both approved treatments for geographic atrophy, but their patent and regulatory profiles differ materially.

Product	Active ingredient	Target	FDA approval	Administration	Patent relevance
Izervay	Avacincaptad pegol	C5	2023	Intravitreal, generally monthly	Covered by sequence-, PEG- and regimen-specific claims
Syfovre	Pegcetacoplan	C3	2023	Intravitreal, monthly or every other month	Separate composition, formulation and method estate

Pegcetacoplan is not the claimed aptamer. Use of Syfovre would not ordinarily satisfy the active-agent limitation in claims 1, 18 or 19. The competitive risk is therefore commercial rather than direct claim overlap.

Neither product is a conventional biosimilar reference product. Avacincaptad pegol is an oligonucleotide aptamer drug, while pegcetacoplan is a complement inhibitor with a different molecular format. A follow-on avacincaptad product would more likely involve an ANDA or a 505(b)(2) pathway, depending on FDA determinations concerning active-ingredient sameness, analytical characterization and substitutability.

What Paragraph IV and generic-entry risks exist?

A generic applicant seeking approval for a product with the same active ingredient, dosage form, route and geographic-atrophy indication could face several patent positions:

1. Invalidity: the claims lack novelty, written description, enablement or definiteness.
2. Noninfringement: the proposed product does not use the claimed sequence, PEG structure, dose or schedule.
3. Section viii carve-out: the applicant omits the patented method from its labeling, if FDA permits the omission.
4. Lack of inducement: the label does not encourage the claimed dosing regimen or indication.
5. Regulatory distinction: the follow-on product is not therapeutically equivalent to the reference product.

For claims 18 and 19, a generic applicant may seek to avoid the efficacy limitations by arguing that the proposed label does not represent or guarantee a 30% or 40% reduction. That argument would not necessarily avoid claims 1 or 9, which do not require those higher thresholds.

The most commercially credible launch scenario is a full-label challenge after core product and formulation patents are evaluated. A carve-out launch would be more difficult because geographic atrophy is the central approved use of Izervay.

What litigation or settlement exposure affects the patent?

The supplied information does not identify a filed district-court case, Paragraph IV notice, inter partes review, post-grant review or settlement agreement involving U.S. Patent 11,273,171. The patent record and court dockets would control the current litigation status.

Potential dispute points include:

• Whether the claim requires the exact SEQ ID NO:26 sequence;
• Whether a salt or chemically modified equivalent falls within the claim;
• The meaning of “about 2 mg/eye”;
• Whether quarterly dosing is enabled and supported;
• Whether “anti-C5 agent” broadens or conflicts with the aptamer limitation;
• Whether lesion-growth reduction is an enforceable claim limitation;
• Whether the patent is subject to a terminal disclaimer with a related patent.

No settlement terms should be inferred from the patent claims or FDA approval record.

What manufacturing and intellectual-property barriers apply?

The manufacturing barrier is higher than for a conventional small-molecule generic. A follow-on manufacturer would need to reproduce or characterize:

• The exact modified RNA sequence;
• 2′-fluoro and 2′-O-methyl substitution patterns;
• The inverted deoxythymidine terminus;
• PEG conjugation chemistry;
• Branched PEG architecture;
• Molecular-weight distribution;
• Purity and aggregate profile;
• Sterility and ophthalmic injectable quality;
• Potency against C5;
• Stability of the PEG-aptamer conjugate.

These technical requirements can support regulatory differentiation even where patent claims are challenged. Manufacturing know-how, analytical methods and process patents may create barriers separate from the claims of U.S. Patent 11,273,171.

Key Takeaways

• U.S. Patent 11,273,171 is primarily a method-of-treatment patent for avacincaptad pegol in geographic atrophy.
• The core combination is a specific modified anti-C5 aptamer, approximately 2 mg per eye, intravitreal administration and biweekly, monthly or quarterly dosing.
• The patent closely tracks the commercial Izervay regimen, particularly its 2 mg monthly intravitreal use.
• Claims 18 and 19 provide narrower protection for branched PEG products above approximately 10 kDa with at least 30% or 40% lesion-growth reduction.
• The patent does not directly cover pegcetacoplan or other non-aptamer complement inhibitors.
• The references to “anti-C5 agent,” “biweekly,” and “bimonthly” create potential claim-construction issues.
• Patent expiration cannot be determined from the claim text or issue date alone.
• A future ANDA challenger would likely assess Paragraph IV, section viii and noninfringement strategies.
• The highest infringement risk applies to a copy of avacincaptad pegol using the same sequence, PEG architecture, 2 mg dose and geographic-atrophy indication.

Frequently Asked Questions

Is U.S. Patent 11,273,171 a composition patent?

No. The supplied claims are method claims. They require administering the specified PEGylated aptamer to treat geographic atrophy. Separate composition or formulation patents may protect the molecule itself.

Does the patent cover every C5 inhibitor?

No. The claims require a particular modified aptamer sequence. They do not, on their face, cover every C5 antibody, peptide, small molecule or unrelated oligonucleotide.

Does quarterly dosing fall within the patent?

Yes. Claim 1 expressly includes quarterly administration. Claims 12 and related language reinforce quarterly dosing coverage.

Can a generic applicant omit geographic atrophy from its label?

A section viii carve-out may be considered only if the resulting label does not encourage the patented use and FDA accepts the omission. For Izervay, geographic atrophy is the central approved indication, making a complete carve-out commercially difficult.

Is avacincaptad pegol a biosimilar product?

No. Avacincaptad pegol is a PEGylated aptamer. A follow-on product would not ordinarily proceed through the standard monoclonal-antibody biosimilar framework solely because it targets C5.

References

Iveric Bio, Inc. (2023). Izervay (avacincaptad pegol) injection: Prescribing information. U.S. Food and Drug Administration.

U.S. Food and Drug Administration. (2023). FDA approves treatment for geographic atrophy secondary to age-related macular degeneration. https://www.fda.gov/

U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov/drugsatfda

U.S. Patent No. 11,273,171. (2022). Methods of treating geographic atrophy. United States Patent and Trademark Office.

Drugs Protected by US Patent 11,273,171

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Astellas	IZERVAY	avacincaptad pegol sodium	SOLUTION;INTRAVITREAL	217225-001	Aug 4, 2023		RX	Yes	Yes	11,273,171					TREATMENT OF GEOGRAPHIC ATROPHY SECONDARY TO AGE-RELATED MACULAR DEGENERATION BY ADMINISTERTING AVACINCAPTAD PEGOL TO THE EYE

International Family Members for US Patent 11,273,171

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2014286996
Australia	2020201824
Australia	2022201404
Australia	2024200948
Australia	2025271125
Brazil	112016000546
Canada	2915255