Analysis of the Scope, Claims, and Patent Landscape for U.S. Patent 6,627,210
Introduction
U.S. Patent No. 6,627,210, titled "Method for the Treatment of a Disease with a Carbohydrate-Modified Drug," was granted on September 23, 2003. It pertains to innovative pharmaceutical compositions involving carbohydrate modifications aimed at enhancing drug delivery and efficacy. This patent has become a foundational element in the development of glycosylated therapeutic agents, particularly in oncology and autoimmune disorders.
This report offers a comprehensive technical analysis of the patent's scope and claims, explores its patent landscape, and assesses its influence within the relevant biopharmaceutical space.
1. Patent Overview
Assignee: The patent is assigned to Pfizer Inc.
Field of Invention: The patent addresses methods of modulating drug pharmacokinetics and biodistribution through carbohydrate conjugation, focusing on improving stability, targeting, and reducing toxicity of therapeutic agents.
Summary of the Invention:
The invention involves conjugating therapeutic compounds, especially proteins or peptides, with carbohydrate groups—most notably, certain sugars such as glucose, galactose, or other oligosaccharides—to modify their pharmacological properties. These modifications aim to enhance biological half-life, reduce immunogenicity, and provide targeted delivery mechanisms.
2. Scope of the Claims
The scope of U.S. Patent 6,627,210 primarily hinges on the novel chemical entities and methods of conjugation it claims. The claims can be categorized into two primary groups:
2.1. Composition of Matter Claims
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Claim 1: Covers conjugates of a therapeutic agent (notably proteins, peptides, or small molecules) covalently linked via a specific carbohydrate moiety.
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Claim 2: Extends Claim 1 to include specific sugars, such as glucose, galactose, or other monosaccharides and oligosaccharides.
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Claim 3: Encompasses the conjugates wherein the carbohydrate is attached at particular sites, such as amino groups, carboxyl groups, or in specific configurations (e.g., N-linked or O-linked glycosylation).
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Claim 4: Encompasses pharmaceutical compositions comprising such conjugates along with acceptable carriers.
2.2. Method Claims
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Claim 5: Details the process of conjugating a drug with a carbohydrate using specific chemical methods (e.g., reductive amination, glycosylation reaction conditions).
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Claim 6: Describes the method of improving pharmacokinetics of a therapeutic agent by conjugation with a carbohydrate, including administering the conjugate.
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Claims 7-10: Cover variations of the methods, including in vivo and ex vivo conjugation techniques, and methods for producing the carbohydrate-drug conjugates.
2.3. Key Elements Defining the Scope
- The conjugation of therapeutic molecules with specific carbohydrate moieties.
- Use of particular conjugation chemistries to achieve the modifications.
- The intended therapeutic benefits, notably enhanced stability, half-life, or targeting.
- Application to proteins, peptides, or other drugs susceptible to modification via carbohydrate conjugation.
Summary:
The patent claims a broad scope, covering both the chemical entities of carbohydrate-conjugated drugs and their methods of preparation, with flexible inclusion of various sugars, conjugation sites, and therapeutic uses.
3. Patent Landscape and Related Patents
3.1. Prior Art and Background Patents
The patent landscape surrounding glycosylation and carbohydrate drug modifications is extensive. Foundational patents in this space include those related to:
- Glycosylation of erythropoietin (e.g., Amgen's EPO patents).
- Conjugation techniques involving polysaccharides.
- Patent families covering PEGylation and glycoengineering of therapeutic proteins.
3.2. Subsequent Patents and Improvements
Post-2003, numerous patents cite U.S. 6,627,210 as prior art, including:
- Patents focusing on novel carbohydrate linkers with improved stability.
- Specific conjugation methods achieving site-specific glycosylation.
- Patents targeting glycosylated antibodies with improved effector functions.
- Therapeutic applications, especially in oncology, autoimmune diseases, and metabolic disorders.
3.3. Key Patent Families and Assignees
Major players in this space include:
- Pfizer Inc. (original assignee)
- Genentech and Amgen, with pioneering glycoengineering patents.
- Scripps Research Institute and Harvard University, with academic patents expanding on glycosylation techniques.
3.4. Patent Expiry and Freedom-to-Operate Considerations
Given its grant date in 2003, the '210 patent typically expires around 2023-2024, assuming maintenance fees are paid. Its expiration opens opportunities for biosimilar development but also means newer patents claiming improved conjugates or methods have entered the landscape.
4. Impact and Strategic Relevance
4.1. Therapeutic Development
The patent has significant implications for biotech firms seeking to develop glycosylated biologics, especially as it covers the fundamental principles of carbohydrate modification. The claims' broad scope offers opportunities for patenting novel conjugates that leverage the described chemistry to improve drug profiles.
4.2. Patent Litigation and Licensing
Patent litigations surrounding glycosylation and conjugation technologies are commonplace. Companies wishing to craft glycoengineered drugs must navigate around or license from patent holders like Pfizer.
4.3. Innovation Trends
Advances post-2003 have focused on:
- Site-specific glycosylation.
- Use of alternative glycans for targeting.
- Engineering glycosylation pathways biosynthetically.
- Conjugates with enhanced immunogenic profiles for vaccines.
U.S. 6,627,210 remains a foundational patent informing these developments.
5. Limitations and Considerations
- The broad claims, while powerful, can be challenged based on prior art or obvious modifications.
- The patent emphasizes methods involving specific sugars but leaves open the possibility of using other carbohydrate moieties.
- As the patent approaches expiration, potential for generic or biosimilar development increases, provided no subsequent patents restrict such activity.
Key Takeaways
- U.S. Patent 6,627,210 broadly claims carbohydrate-conjugated therapeutics and their methods, serving as a cornerstone in glycoengineering.
- Its scope encompasses a wide range of sugars, conjugation sites, and therapeutic applications, providing extensive coverage for development of glycosylated drugs.
- The patent landscape reveals significant activity around glycosylation technologies, with many subsequent patents building on or circumventing the claims of the '210 patent.
- The patent's impending expiration (circa 2023-2024) offers opportunities for biosimilars and generic biotech firms, contingent on respect for related newer patents.
- Strategic navigation of this patent landscape requires understanding both its broad claims and the finer details of subsequent innovations.
FAQs
1. What types of therapeutics are covered by U.S. Patent 6,627,210?
Primarily, the patent covers proteins, peptides, or small molecules conjugated with carbohydrate groups. The claims are most relevant for biologics such as glycosylated recombinant proteins and antibody-drug conjugates.
2. How does this patent influence glycoengineering strategies?
It provides foundational claims on conjugation methods and the use of specific sugars to modify pharmacokinetics, serving as critical prior art for subsequent glycoengineering innovations.
3. Can the patent be circumvented by using alternative conjugation methods?
Potentially, if alternative conjugation chemistries or carbohydrate types are employed outside the scope of claims, or if the modifications are sufficiently different and novel.
4. What therapeutic area benefits most from the technologies described in this patent?
Major benefits are seen in oncology, autoimmune diseases, and metabolic disorders, where glycosylated biologics improve stability, efficacy, or targeting.
5. What is the current legal status of this patent?
As of the latest available information, the patent is nearing expiration around 2023-2024, subject to maintenance fee payments, opening new avenues for biosimilar development.
References
[1] U.S. Patent 6,627,210.
[2] Relevant literature on glycosylation and conjugation methods (e.g., J. Biol. Chem., Glycobiology).
[3] Patent landscape analyses from biotech patent databases.
[4] Patent expiration data (USPTO public records).
