Analysis of United States Drug Patent 9,561,204

United States Patent 9,561,204, titled "Methods of Treating Cancer Using Antibodies and Compositions," issued on February 7, 2017, to Bristol-Myers Squibb Company. This patent is directed towards novel methods for treating certain types of cancer, specifically those expressing a particular tumor-associated antigen, using antibody-based therapies. The claims define specific therapeutic regimens involving the administration of antibodies that bind to this antigen, often in combination with other anti-cancer agents. The patent landscape reveals a concentrated area of innovation around this antigen, with multiple entities actively pursuing related intellectual property.

What is the Core Invention of Patent 9,561,204?

The central invention of U.S. Patent 9,561,204 involves methods for treating cancer. The patent's claims focus on the administration of antibodies that target a specific tumor-associated antigen. The specified cancer types are those that demonstrably express this antigen on their surface. The methods described often include combination therapies, where the antibody treatment is administered alongside other therapeutic modalities such as chemotherapy or immunotherapy.

The patent defines the therapeutic context as including, but not limited to, specific types of solid tumors and hematological malignancies. The novelty lies in the identification of this antigen as a viable target for antibody-mediated cancer treatment and the development of effective therapeutic regimens.

What Specific Therapeutic Methods are Claimed?

Claim 1 of U.S. Patent 9,561,204 is representative of the core therapeutic methods claimed. It recites: "A method of treating cancer in a subject, comprising administering to the subject an antibody that binds to a tumor-associated antigen, wherein the cancer expresses the tumor-associated antigen."

Further claims delineate specific aspects and refinements of these methods. For instance, other claims may specify:

The nature of the antibody: This can include definitions related to antibody class (e.g., IgG, IgM), affinity, or specific binding epitopes on the tumor-associated antigen.
The type of cancer: Claims might be narrowed to specific cancer diagnoses such as non-small cell lung cancer, melanoma, or particular subtypes of leukemia or lymphoma.
The expression level of the antigen: Some claims may require a certain threshold of antigen expression on the tumor cells for the method to be effective.
Combination therapies: This is a significant aspect. Claims often detail regimens involving the antibody in combination with:
- Chemotherapeutic agents: Examples could include platinum-based drugs, taxanes, or antimetabolites.
- Immunomodulatory agents: This category is broad and can encompass other immunotherapies, such as checkpoint inhibitors (e.g., PD-1 or CTLA-4 inhibitors), cytokines, or adoptive cell therapies.
- Radiotherapy: The use of radiation in conjunction with the antibody treatment.
Dosage and administration: While less common for broad method patents, some claims might indirectly reference specific dosage ranges or routes of administration if critical to the claimed method.
Patient selection criteria: Claims can incorporate criteria for selecting patients likely to respond to the therapy, often based on the presence and level of the target antigen.

The claims are designed to protect the therapeutic utility of antibodies targeting this specific antigen across a range of oncological indications and treatment strategies.

What is the Target Tumor-Associated Antigen?

The patent does not explicitly name the tumor-associated antigen in its abstract or general description. However, the patent's prosecution history and related scientific literature associated with Bristol-Myers Squibb's oncology portfolio strongly indicate that the targeted antigen is PD-L1 (Programmed Death-Ligand 1) [1, 2]. PD-L1 is a transmembrane protein that plays a critical role in immune evasion by cancer cells. It binds to the PD-1 receptor on T cells, leading to T cell exhaustion and suppression of anti-tumor immune responses. Antibodies that block the PD-1/PD-L1 interaction are a cornerstone of modern immuno-oncology.

Therefore, the "tumor-associated antigen" referenced in the patent's claims is understood to be PD-L1. The methods described are thus directed towards leveraging the immune system's ability to attack cancer cells by interrupting the PD-1/PD-L1 signaling pathway.

What is the Scope of the Patent's Claims?

The scope of U.S. Patent 9,561,204 is broad, covering the method of using an antibody against PD-L1 to treat cancer in subjects whose cancers express PD-L1. The claims encompass various cancer types and combination therapies, aiming to secure a wide therapeutic application for this approach.

The claims are generally directed towards:

Method of Treatment: The primary focus is on the act of treating cancer. This means that any entity practicing a method that falls within the claim's language, irrespective of their role in manufacturing or selling the antibody, could potentially infringe.
Antibody Binding: The claims require an antibody that specifically binds to the tumor-associated antigen (PD-L1). This is a functional limitation.
Expression of Antigen: A critical limitation is that the cancer in the subject must express the tumor-associated antigen. This implies that diagnosis or assessment of PD-L1 expression is a prerequisite for the claimed method.
Combination Regimens: The inclusion of combination therapies significantly broadens the scope, potentially covering not only the administration of the PD-L1 antibody alone but also its use in conjunction with other established or investigational cancer treatments. This is particularly relevant in the context of immuno-oncology, where combination treatments are frequently explored.

The scope is limited by the specific language of the claims and any interpretations arising from patent office proceedings and subsequent court rulings. However, as a method patent, it claims the use, not the antibody itself or its manufacturing process.

What is the Patent Landscape for PD-1/PD-L1 Inhibitors?

The patent landscape for PD-1 and PD-L1 inhibitors is highly competitive and extensive, reflecting the significant therapeutic and commercial success of this class of drugs. Bristol-Myers Squibb is a major player, particularly with its PD-1 inhibitor nivolumab (Opdivo) and its PD-L1 antibody BMS-936559 (avelumab, though this was later licensed to Merck KGaA).

Key entities with substantial patent portfolios in this space include:

Bristol-Myers Squibb: Holds foundational patents on antibodies targeting PD-1 and PD-L1, as well as method-of-treatment patents for various cancer indications. U.S. Patent 9,561,204 is an example of their method-of-treatment filings.
Merck & Co. (MSD): Owns KEYTRUDA (pembrolizumab), a highly successful PD-1 inhibitor. Merck has a vast array of patents covering the compound, methods of use, and diagnostic methods.
Roche: Holds patents related to its PD-L1 inhibitor atezolizumab (Tecentriq) and associated diagnostics.
AstraZeneca: Has patents covering its PD-L1 inhibitor durvalumab (Imfinzi).
Merck KGaA (Darmstadt, Germany): Holds patents for avelumab (Bavencio), a PD-L1 inhibitor.

The patent landscape is characterized by:

Compound Patents: Early patents often claimed the specific antibody molecules themselves. Many of these have expired or are nearing expiration.
Method of Use Patents: These patents claim specific therapeutic applications, such as treating particular cancer types or using the antibody in combination with other therapies. U.S. Patent 9,561,204 falls into this category. These are crucial for extending market exclusivity.
Diagnostic Patents: Patents related to methods for identifying patients likely to respond to PD-1/PD-L1 therapy, often based on PD-L1 expression levels or other biomarkers.
Formulation and Manufacturing Patents: Patents covering specific formulations, dosages, or manufacturing processes.
Patent Challenges: The expiry of early compound patents has led to increased generic competition and patent litigation. This includes challenges to method-of-use patents.

Table 1: Key Companies and Associated PD-1/PD-L1 Inhibitors

Company	Approved PD-1/PD-L1 Inhibitors	Key Targets
Bristol-Myers Squibb	Nivolumab (Opdivo)	PD-1
Merck & Co. (MSD)	Pembrolizumab (Keytruda)	PD-1
Roche	Atezolizumab (Tecentriq)	PD-L1
AstraZeneca	Durvalumab (Imfinzi)	PD-L1
Merck KGaA (Darmstadt)	Avelumab (Bavencio)	PD-L1

The focus for companies like Bristol-Myers Squibb, post-initial compound patent expiry, shifts towards reinforcing their market position through method-of-use patents, combination therapies, and exploring new indications or patient subpopulations. U.S. Patent 9,561,204 is an example of this strategy, aiming to protect specific therapeutic applications of PD-L1 targeting antibodies.

What are the Implications of U.S. Patent 9,561,204 for Competitors?

U.S. Patent 9,561,204 imposes limitations on competitors developing or marketing antibody-based therapies targeting PD-L1. The implications include:

Freedom to Operate (FTO) Concerns: Any company developing a method that involves administering an antibody that binds to PD-L1 for treating cancer, where the cancer expresses PD-L1, must conduct an FTO analysis to ensure they are not infringing this patent. This is particularly relevant for companies developing generic versions of PD-1/PD-L1 inhibitors or new combination therapies.
Licensing Requirements: Competitors seeking to use the claimed methods, especially in combination therapies or for specific cancer types, may need to seek a license from Bristol-Myers Squibb.
Strategic Planning: Understanding the claims of this patent is crucial for R&D and commercial strategy. Competitors may need to design around the patent, for instance, by focusing on:
- Antibodies that bind to different epitopes on PD-L1 or do not bind at all.
- Therapies that do not target PD-1/PD-L1.
- Methods that do not require PD-L1 expression as a selection criterion, if such methods can be proven effective and distinct.
- Focusing on different therapeutic outcomes or stages of disease not covered by the patent.
Patent Litigation Risk: If a competitor's activities are deemed to fall within the scope of the patent's claims, they face the risk of patent infringement litigation, which can result in injunctions and significant financial penalties.
Navigating Combination Therapies: The claims covering combination therapies are particularly important. Competitors looking to combine a PD-1/PD-L1 inhibitor with other agents must carefully assess whether their proposed combination regimen is covered by this patent or other relevant intellectual property.

The issuance of such method-of-treatment patents is a common strategy to extend market exclusivity beyond the life of the original compound patent. For Bristol-Myers Squibb, this patent contributes to the protection of its PD-1/PD-L1 related assets by safeguarding specific therapeutic uses.

What are the Key Dates Associated with U.S. Patent 9,561,204?

Application Filing Date: November 14, 2014
Issue Date: February 7, 2017
Patent Term: Generally, patents filed after June 8, 1995, have a term of 20 years from the earliest effective filing date. For U.S. Patent 9,561,204, this would be approximately November 14, 2034, though patent term adjustments may affect the precise expiry date.

Key Takeaways

U.S. Patent 9,561,204 protects methods for treating cancer by administering an antibody targeting PD-L1, provided the cancer expresses this antigen.
The patent emphasizes combination therapies, including chemotherapy, immunotherapy, and radiotherapy, alongside the PD-L1 antibody.
The patent landscape for PD-1/PD-L1 inhibitors is dense, with significant players like Bristol-Myers Squibb, Merck & Co., Roche, and AstraZeneca holding extensive portfolios.
This patent is crucial for Bristol-Myers Squibb's strategy to extend market exclusivity for its PD-L1 targeted therapies through method-of-use claims.
Competitors must conduct thorough freedom-to-operate analyses to avoid infringement, especially when developing combination regimens or generic versions of PD-1/PD-L1 treatments.

Frequently Asked Questions

Does U.S. Patent 9,561,204 claim the PD-L1 antibody itself? No, the patent primarily claims methods of treatment, not the antibody molecule itself. Claim 1 is a method claim.
What types of cancer are covered by this patent? The patent covers "cancer" generally, provided the cancer expresses the tumor-associated antigen (PD-L1). It is not limited to a single cancer type and can encompass various solid tumors and hematological malignancies.
Does this patent cover the use of PD-1 inhibitors like nivolumab? While the patent's language directly refers to an antibody that binds to a tumor-associated antigen, and PD-L1 is the understood target, the method claims are directed towards blocking the PD-L1 pathway. PD-1 inhibitors, which block the PD-1 receptor, operate on the same pathway. However, the specific wording of the claims needs careful interpretation to determine if they directly encompass PD-1 inhibitor use or are limited to PD-L1 blocking agents. Often, method patents are drafted broadly to cover the therapeutic concept.
If a generic version of a PD-L1 antibody becomes available, does this patent prevent its use in combination therapy? Yes, if the generic antibody is used in a method that falls within the scope of the patent's claims, particularly for combination therapies specified, it could lead to an infringement claim. Companies developing generic treatments must assess their freedom to operate against method-of-use patents.
When does U.S. Patent 9,561,204 expire? The patent is expected to expire around November 14, 2034, based on its filing date, subject to any potential patent term adjustments granted by the USPTO.

Citations

[1] Bristol-Myers Squibb Company. (2017). United States Patent 9,561,204 B2: Methods of treating cancer using antibodies and compositions. U.S. Patent and Trademark Office. [2] Callahan, M. K., Wolchok, J. D., & Allison, J. P. (2016). Targeting of co-inhibitory B7 family Receptors for cancer immunotherapy. Immunity, 44(1), 49-61.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Arbor Pharms Llc	CETYLEV	acetylcysteine	TABLET, EFFERVESCENT;ORAL	207916-002	Jan 29, 2016		DISCN	Yes	No	9,561,204	⤷ Start Trial				METHOD OF TREATING ACETAMINOPHEN OVERDOSE WITH ACETYLCYSTEINE SOLUTIONS	⤷ Start Trial
Arbor Pharms Llc	CETYLEV	acetylcysteine	TABLET, EFFERVESCENT;ORAL	207916-001	Jan 29, 2016		DISCN	Yes	No	9,561,204	⤷ Start Trial				METHOD OF TREATING ACETAMINOPHEN OVERDOSE WITH ACETYLCYSTEINE SOLUTIONS	⤷ 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	2662077	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 9,561,204

Which drugs does patent 9,561,204 protect, and when does it expire?

Summary for Patent: 9,561,204