US Patent 7,824,679: CTLA-4 Antibody Claims, Patent Scope, Expiration, and Competitive Landscape

US Patent 7,824,679 covers defined human anti-CTLA-4 antibodies and antibody fragments using specified heavy- and light-chain variable-region sequences. Its claims are sequence-specific rather than a broad monopoly over every CTLA-4 antibody. The patent is associated with the Medarex anti-CTLA-4 antibody program that produced ipilimumab, marketed by Bristol Myers Squibb as Yervoy.

The patent’s ordinary US patent term expired in the early 2020s, and the patent is not a current standalone barrier to commercial development in 2025. Its historical importance remains significant because it covers antibody sequence combinations, full immunoglobulins, fragments, pharmaceutical compositions, and tumor-treatment methods. It does not, by itself, establish current exclusivity for Yervoy or every later-generation CTLA-4 product.

What does US Patent 7,824,679 cover?

The patent claims human monoclonal antibodies that bind CTLA-4 and contain specified combinations of variable heavy-chain and variable light-chain sequences.

The core claim architecture is:

Claim group	Subject matter	Main limitation
Claims 1-5	Human anti-CTLA-4 antibody, fragments, compositions, and tumor treatment	Nine listed VH/VL sequence pairings
Claims 6-7	Monoclonal antibody or antigen-binding portion	Full-chain sequence combinations, including SEQ ID NOS: 66/67 and 68/69
Claims 8-13	Anti-CTLA-4 antibody defined by heavy chain	Selected heavy-chain sequences
Claims 14-19	Anti-CTLA-4 antibody defined by light chain	Selected light-chain sequences

The claims expressly include Fab, F(ab')2, Fv, single-chain antibodies, bispecific antibodies, and immunoglobulin classes including IgG, IgM, IgE, IgA, and IgD. The patent therefore reaches beyond a conventional full-length IgG1 product, at least at the claim-language level.

The claims also cover:

Pharmaceutical compositions containing the claimed antibody.
Methods of treating a tumor by administering the antibody.
Antibodies with specified full heavy- and light-chain sequences.
Antibodies defined by selected heavy-chain sequences alone.
Antibodies defined by selected light-chain sequences alone.
Bispecific and fragment formats.

The patent does not claim every antibody that binds CTLA-4. A competing antibody with different CDRs and different variable-region sequences would generally fall outside the literal sequence limitations, subject to any doctrine-of-equivalents analysis and the scope of other patents.

What antibody sequences are claimed by US 7,824,679?

Claim 1 lists nine heavy-chain/light-chain variable-domain pairings:

Pairing	Heavy-chain variable sequence	Light-chain variable sequence
A	SEQ ID NO: 73	SEQ ID NO: 95
B	SEQ ID NO: 75	SEQ ID NO: 89
C	SEQ ID NO: 76	SEQ ID NO: 92
D	SEQ ID NO: 78	SEQ ID NO: 90
E	SEQ ID NO: 79	SEQ ID NO: 91
F	SEQ ID NO: 81	SEQ ID NO: 97
G	SEQ ID NO: 82	SEQ ID NO: 98
H	SEQ ID NO: 83	SEQ ID NO: 114
I	SEQ ID NO: 84	SEQ ID NO: 116

Claims 6 and 7 separately identify complete heavy-chain and light-chain combinations. Claim 7 narrows the coverage to:

Heavy chain SEQ ID NO: 66 with light chain SEQ ID NO: 67.
Heavy chain SEQ ID NO: 68 with light chain SEQ ID NO: 69.

Claims 8-19 create additional claim sets around individual heavy- or light-chain sequences. Those claims may be useful against products containing one claimed chain in combination with a different constant region or antibody format, although infringement depends on the precise claim language, product construction, and applicable claim interpretation.

How broad are the claims?

The claims are broad in format but narrow in sequence.

Broad elements

The patent expressly covers multiple molecular formats:

Full-length antibodies.
Fab and F(ab')2 fragments.
Fv fragments.
Single-chain antibodies.
Bispecific antibodies.
Multiple immunoglobulin isotypes.
Pharmaceutical compositions.
Tumor-treatment methods.

A product does not avoid the patent merely because it is an antibody fragment or bispecific molecule if it retains the claimed variable-region sequence or another limitation required by the asserted claim.

Narrow elements

The principal limitation is the specified antibody sequence. Claim 1 does not simply require binding CTLA-4. It requires the listed heavy- and light-chain variable-domain combinations. Claims 6-19 similarly depend on particular chains or sequence sets.

This structure creates a conventional sequence-defined antibody patent:

The patent has meaningful coverage of the disclosed antibody clones.
It has limited reach against unrelated anti-CTLA-4 antibodies.
It may cover biosimilar or follow-on products that reproduce the claimed antibody sequences.
It is less likely to block a new antibody discovered through an independent sequence program.

The claim language also creates construction issues. The phrase "comprises" can preserve some flexibility, but the recited variable-domain sequences remain the central technical limitation. Constant-region substitutions, glycoengineering, Fc modifications, linker changes, or fusion to another binding domain would not necessarily remove infringement if the claimed variable-region sequences remain present.

Does US Patent 7,824,679 cover ipilimumab?

The patent is part of the Medarex anti-CTLA-4 patent family associated with ipilimumab development. Ipilimumab is a recombinant human monoclonal antibody against CTLA-4 and is marketed in the United States as Yervoy by Bristol Myers Squibb.

The patent should not be treated as the only patent relevant to ipilimumab. Commercial protection for Yervoy has involved a portfolio that includes:

Antibody sequence patents.
Antibody and antigen-binding-fragment patents.
Pharmaceutical-composition claims.
Treatment-method claims.
Formulation and manufacturing rights.
Regulatory exclusivity and patent-term extensions on selected patents.

The relevant question for an infringement or freedom-to-operate analysis is not whether a product is generally "anti-CTLA-4." It is whether the product contains the claimed sequences, practices a claimed method, or falls within another live patent in the broader Yervoy portfolio.

When did US Patent 7,824,679 lose exclusivity?

US Patent 7,824,679 is no longer an active enforceable patent under its ordinary patent term. The patent traces to an early anti-CTLA-4 filing priority date and reached the end of its 20-year US term in the early 2020s, generally associated with a March 2020 expiration date for the underlying priority chain.

The key distinction is between this patent and other Yervoy-related patents:

Exclusivity category	Status relevant to US 7,824,679
Ordinary patent term	Expired by 2025
Patent-term adjustment	Must be assessed against the specific USPTO term calculation
Patent-term extension	Does not automatically apply to every family member
FDA biologic exclusivity	Separate from patent expiration
Data exclusivity	Does not revive an expired patent
Orange Book listing	Biologics are generally handled through the Purple Book rather than the Orange Book
Biosimilar competition	Governed by the BPCIA, not an ANDA Paragraph IV process

A patent-term extension awarded to another Yervoy-related patent would not automatically extend US 7,824,679. Each patent requires a separate term analysis, and a regulatory extension attaches to the patent identified in the extension application.

What is the FDA regulatory status of the product associated with this patent?

Ipilimumab is approved by the FDA under Biologics License Application No. 125377 and is marketed as Yervoy. It is approved for multiple oncology indications, including melanoma, renal cell carcinoma, colorectal cancer with specified molecular characteristics, hepatocellular carcinoma, non-small cell lung cancer, mesothelioma, esophageal cancer, and other uses depending on the current labeling.

The product is a biologic, not a conventional small-molecule drug. The principal US follow-on pathway is therefore a biosimilar application under section 351(k) of the Public Health Service Act.

The patent itself does not establish FDA approval. Its treatment claims may overlap with approved Yervoy indications, but regulatory approval and patent infringement are separate legal questions.

What is the Orange Book status of US Patent 7,824,679?

US Patent 7,824,679 should not be analyzed as an ordinary Orange Book patent for Yervoy. The Orange Book primarily lists patents for approved drug products approved through the NDA pathway. Yervoy is licensed as a biologic under a BLA.

Biologic patent information is generally analyzed through:

The FDA Purple Book.
Public patent records.
The BLA sponsor’s patent disclosures.
The BPCIA patent-exchange and litigation framework.
Relevant patent-term and regulatory-extension records.

The absence of an Orange Book listing does not mean that no patent rights affect Yervoy. It means that the Orange Book Paragraph IV framework is not the principal mechanism for this biologic.

Are there Paragraph IV challenges to US Patent 7,824,679?

A conventional ANDA Paragraph IV challenge is not the expected pathway for a biosimilar version of Yervoy because ipilimumab is a biologic. A biosimilar applicant proceeds under section 351(k), not through an ANDA.

The relevant risks are:

Challenge type	Relevance to this patent
ANDA Paragraph IV certification	Generally not applicable to Yervoy as a biologic
BPCIA patent exchange	Potentially applicable to a proposed ipilimumab biosimilar
Declaratory-judgment action	Possible in defined circumstances
Patent-infringement litigation	Possible if a biosimilar sponsor markets a product alleged to practice a live patent
Invalidity defense	Available in litigation against an asserted patent
Inter partes review	Potentially available for eligible patent claims, subject to timing and statutory limits

Because US 7,824,679 is expired, a new biosimilar applicant would normally focus on live patents, regulatory exclusivity, manufacturing know-how, and other family members rather than challenge this patent as a current launch barrier.

Which companies are challenging Yervoy exclusivity?

The competitive threat is more likely to come from biosimilar developers and oncology competitors than from an ANDA applicant targeting US 7,824,679.

Potential competitive groups include:

Large biologics manufacturers developing CTLA-4 biosimilars.
Companies developing next-generation CTLA-4 antibodies.
Developers of Fc-engineered CTLA-4 antibodies.
Combination-immunotherapy companies.
Sponsors developing dual-checkpoint or tumor-targeted immune agonists.

Public commercial competition against Yervoy also comes from nivolumab, pembrolizumab, atezolizumab, durvalumab, tislelizumab, and other checkpoint inhibitors. These products do not necessarily infringe the patent because they target different immune-checkpoint molecules or use different antibody sequences.

No conventional generic challenge to Yervoy under the Hatch-Waxman Paragraph IV process should be inferred from the existence of this patent.

How strong is the patent estate for ipilimumab?

The estate is strongest against exact or near-exact copies of the disclosed antibody sequences and weaker against independently discovered CTLA-4 antibodies.

Strengths

The claims identify antibody sequences rather than relying only on a functional binding test.
Claims cover multiple antibody formats.
Claims extend to pharmaceutical compositions.
Claims include tumor-treatment methods.
The sequence disclosures may support related continuation patents.
The commercial product has substantial regulatory and clinical value.

Weaknesses

US 7,824,679 itself is expired.
The claims do not monopolize all CTLA-4 antibodies.
New antibodies with materially different CDRs may avoid literal infringement.
Antibody-sequence claims can face written-description, enablement, anticipation, obviousness, and claim-construction attacks.
Treatment claims may be limited by the claimed antibody identity and the specified disease-treatment activity.
Biologic competitors can design around the disclosed variable regions.

Patent strength must therefore be evaluated at the portfolio level. This patent alone is not a current blocking right.

What formulations are protected by this patent?

Claims 4, 12, and 18 cover pharmaceutical compositions containing the claimed antibody or antigen-binding portion and a pharmaceutically acceptable carrier.

These claims are composition claims, but they are not detailed formulation claims in the conventional sense. The provided claims do not specify:

A precise antibody concentration.
A named buffer.
A defined pH range.
A surfactant.
A stabilizer.
A container closure system.
A freeze-drying cycle.
A specific subcutaneous or intravenous presentation.

A later patent could provide narrower protection for a particular Yervoy formulation, concentration, excipient system, or manufacturing process. Claim 4 should not be treated as a substitute for a dedicated formulation patent.

What manufacturing and intellectual-property barriers remain?

The antibody sequence is only one part of commercial entry risk. A biosimilar or follow-on developer must address:

Cell-line development.
Vector construction.
Expression yield.
Protein folding and aggregation.
Glycosylation control.
Fc-receptor activity.
CTLA-4 binding and functional activity.
Process impurities.
Viral clearance.
Comparability to the reference product.
Analytical similarity.
Clinical or confirmatory evidence.
Manufacturing-site qualification.
Interchangeability requirements, if sought.

The patent may be expired, but manufacturing know-how and regulatory complexity can remain material barriers. Trade secrets relating to cell culture, purification, formulation, analytical methods, and release specifications are not disclosed by the patent and do not expire on the patent timetable.

What litigation and settlement issues affect this patent?

US 7,824,679 should be separated from the broader Yervoy patent portfolio in litigation analysis.

A litigation review should examine:

Whether the patent was asserted against a specific defendant.
Whether the patent was challenged in district court or at the Patent Trial and Appeal Board.
Whether any asserted claims were cancelled, amended, disclaimed, or held invalid.
Whether the patent was subject to a terminal disclaimer.
Whether a settlement licensed the patent or related family members.
Whether a settlement permitted an early biosimilar launch.
Whether the allegedly relevant patent was still unexpired when the dispute arose.

The absence of an identified Paragraph IV case is not surprising because Yervoy is a biologic. Settlement analysis is more likely to arise in BPCIA litigation or licensing negotiations involving live patents in the ipilimumab portfolio.

How does this patent compare with competing CTLA-4 patent strategies?

Strategy	US 7,824,679 approach	Newer competing approach
Claim basis	Specific VH/VL and full-chain sequences	Often sequence, epitope, function, or combination claims
Product scope	Disclosed antibody clones and formats	May target novel antibodies or engineered variants
Treatment coverage	Tumor-treatment methods	Disease-specific combination regimens
Formulation coverage	Broad carrier claims	Concentration, buffer, container, or stability claims
Commercial risk	High for exact sequence copies historically	Depends on live patent term and clinical use
Design-around potential	Moderate to high using different sequences	Varies by functional and epitope claim breadth
Current enforceability	Expired	Depends on each competitor’s filing date and status

The patent’s commercial value was greatest before expiration and during the period when ipilimumab had regulatory and market exclusivity. Its current value is primarily historical, evidentiary, and relevant to patent-family reconstruction.

What generic or biosimilar launch scenarios exist?

Scenario 1: Exact-sequence biosimilar

An ipilimumab biosimilar reproducing the claimed variable regions could have faced this patent historically. In 2025, the expired status of US 7,824,679 reduces its direct launch significance. Live related patents would remain the principal issue.

Scenario 2: Sequence-distinct CTLA-4 antibody

A new CTLA-4 antibody with different variable regions would generally have a stronger design-around position against this patent. It could still face other patents covering CTLA-4 epitopes, functional activity, combinations, formulations, or manufacturing.

Scenario 3: Bispecific CTLA-4 product

Claims 2, 10, and 16 expressly include bispecific formats. A bispecific containing a claimed anti-CTLA-4 variable region could have faced the patent during its term. A bispecific using an unrelated CTLA-4 binder would require a separate analysis.

Scenario 4: Fragment or Fc-engineered product

Changing the constant region, Fc function, or molecular format would not necessarily avoid claims that recite the variable-domain sequence. A product using different variable regions would present a stronger noninfringement position.

What is the revenue exposure associated with this patent?

Yervoy generated approximately $2 billion or more in annual worldwide revenue in recent years, depending on the reporting period and exchange-rate treatment. Bristol Myers Squibb has reported Yervoy as a major oncology product, frequently in combination with Opdivo.

That revenue should not be attributed exclusively to US Patent 7,824,679. The commercial exposure is distributed across:

The full patent portfolio.
FDA regulatory exclusivity.
Clinical-data protection.
Manufacturing know-how.
Combination-treatment positioning.
Physician adoption.
The absence or timing of biosimilar competition.

The patent’s expiration does not imply an immediate generic-style erosion event. Biologic manufacturing, FDA review, interchangeability, physician switching, payer controls, and remaining patents can delay or moderate competition.

Geographic coverage of US Patent 7,824,679

US Patent 7,824,679 provides rights only in the United States. Parallel rights must be evaluated country by country through the relevant national-stage or direct-application patents.

A global freedom-to-operate review should examine:

European Patent Office family members.
United Kingdom rights.
Canadian patents.
Japanese patents.
Australian patents.
Chinese patents.
South Korean patents.
Patent-term adjustments or extensions.
Local regulatory exclusivity.
National litigation and settlement records.

Expiration in the United States does not establish expiration in other jurisdictions. Conversely, an expired foreign counterpart does not affect US rights.

Key Takeaways

US Patent 7,824,679 claims human anti-CTLA-4 antibodies defined primarily by specified heavy- and light-chain sequences.
Claims 1-19 cover antibodies, fragments, bispecifics, immunoglobulin formats, compositions, and tumor-treatment methods.
The patent is associated with the Medarex anti-CTLA-4 program underlying ipilimumab and Yervoy.
It does not broadly cover every CTLA-4 antibody.
Its principal historical strength was protection against products reproducing the disclosed antibody sequences.
The patent’s ordinary US term expired in the early 2020s and is not a current standalone launch barrier in 2025.
Yervoy is a biologic, so biosimilar and BPCIA analysis is more relevant than an ANDA Paragraph IV analysis.
Orange Book analysis should not be substituted for Purple Book and BPCIA review.
Current commercial risk depends on live related patents, regulatory exclusivity, manufacturing know-how, and the remaining Yervoy portfolio.
Exact-sequence copies, fragments, bispecifics, and engineered formats require claim-by-claim analysis rather than a simple anti-CTLA-4 classification.

FAQs

Does US Patent 7,824,679 claim the Yervoy brand name?

No. The patent claims antibody molecules, antibody fragments, compositions, and treatment methods. It does not claim the Yervoy trademark or brand identity.

Can a CTLA-4 biosimilar avoid this patent by changing the Fc region?

Changing the Fc region may not avoid a claim that requires the same variable-region sequence. The result depends on the asserted claim and whether the product retains the claimed heavy- and light-chain limitations.

Does patent expiration permit immediate substitution of a Yervoy biosimilar?

No. A biosimilar sponsor still requires FDA approval, must satisfy applicable BPCIA requirements, and may face other live patents, regulatory barriers, manufacturing constraints, or interchangeability issues.

Are the tumor-treatment claims limited to melanoma?

The provided claims recite treating a tumor and do not identify melanoma as the sole disease. The enforceable scope depends on claim construction, specification support, prosecution history, and the precise antibody used.

Does an expired antibody patent eliminate trade-secret risk?

No. Patent expiration ends the patent right, but it does not disclose or eliminate manufacturing trade secrets, process controls, cell-line information, analytical methods, or confidential regulatory data.

References

Medarex, Inc. (2010). Human anti-CTLA-4 antibodies, U.S. Patent No. 7,824,679. U.S. Patent and Trademark Office.
U.S. Food and Drug Administration. (2024). Yervoy (ipilimumab) prescribing information. Bristol Myers Squibb.
U.S. Food and Drug Administration. (2024). Purple Book: Database of licensed biological products. https://purplebooksearch.fda.gov/
Bristol Myers Squibb. (2024). Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. Bristol Myers Squibb.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. U.S. Department of Health and Human Services.

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Bristol-myers Squibb Company	YERVOY	ipilimumab	Injection	125377	March 25, 2011	7,824,679	2027-10-31
Octapharma Pharmazeutika Produktionsges.m.b.h.	CUTAQUIG	immune globulin subcutaneous (human)-hipp	Solution	125668	December 12, 2018	7,824,679	2027-10-31
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Country	Patent Number	Estimated Expiration
African Regional IP Organization (ARIPO)	1590	⤷ Start Trial
Austria	E458008	⤷ Start Trial
Australia	2214900	⤷ Start Trial
Australia	772676	⤷ Start Trial
Bulgaria	105722	⤷ Start Trial
Bulgaria	65899	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration

Patent: 7,824,679

Summary for Patent: 7,824,679