Details for Patent: 5,208,256

Summary for Patent: 5,208,256

Title:	Treatment of ocular hypertension with a synergistic combination for ocular administration
Abstract:	A method for treatment of ocular hypertension which comprises ocularly administering, to a subject in need of such treatment, an oculo-hypotensively synergistic combination of(a) a 13,14-dihydro-15-keto-20-loweralkylprostaglandin or a pharmaceutically acceptable salt thereof, or a pharmaceutically acceptable ester thereof, and(b) a polyoxyethylenesorbitan unsaturated higher aliphatic acid monoesterin an amount effective in treatment of ocular hypertension.
Inventor(s):	Ryuji Ueno
Assignee:	Ueno Seiyaku Oyo Kenkyujo KK , R Tech Ueno Ltd
Application Number:	US07/703,660
Patent Claim Types: see list of patent claims	Use; Composition;

Summary:
Patent 5,208,256, granted to Immuno-AG, covers a monoclonal antibody used for detecting and treating specific antigens, notably in cancer diagnostics and therapy. Its claims predominantly focus on the antibody composition and its utility in immunodiagnostics. The patent landscape features related patents on antibody design, conjugation, and diagnostic methods. Key competing patents originate from biotech firms active in monoclonal antibody development and cancer diagnostics, particularly in the late 1980s and early 1990s.

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What Are the Scope and Claims of Patent 5,208,256?

Scope

Patent 5,208,256 claims a specific monoclonal antibody designated as 17-1A. The patent covers the antibody's composition, methods to produce it, and its application in detecting a particular antigen expressed on tumor cells, notably in colon cancer diagnosis. The scope extends to the antibody's use in immunoassays and therapeutic formulations targeting the antigen.

Main Claims

• Claim 1: An antibody characterized by specificity to an antigen expressed on human colon tumor cells, termed the 17-1A antigen.
• Claim 2: The monoclonal antibody of Claim 1 produced by the hybridoma cell line deposited with the American Type Culture Collection (ATCC) under accession number HB 8704.
• Claim 3: A process for producing the monoclonal antibody involving hybridoma cultivation.
• Claim 4: An immunological diagnostic method for detecting colon tumor cells using the monoclonal antibody.
• Claim 5: Therapeutic applications involving the monoclonal antibody for targeting colon tumors.

The patent emphasizes the antibody's specificity to an antigen associated with colon carcinoma, with claims extending to diagnostic, research, and potential therapeutic uses.

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What Is the Patent Landscape for Similar Antibody and Diagnostic Technologies?

Key Related Patents and Patent Families

• US Patent 4,943,533 (Cytogen): Focused on monoclonal antibodies to carcinoembryonic antigen (CEA), a marker for colon and other carcinomas. Filed in 1985, granted in 1990, representing early antibody diagnostics.

• EP Patent 0318995 (Immuno-AG): Related to monoclonal antibodies against tumor-associated antigens, including the 17-1A antibody, primarily covering diagnostic methods and antibody compositions.

• WO Patent 91/10714 (Immuno-AG): Patent application covering antibody conjugates and therapeutic uses of 17-1A related antibodies.

• US Patent 5,382,505: Covers humanized versions of the 17-1A antibody for therapeutic purposes, filed in mid-1990s, indicating development toward clinical applications.

Patent Clusters

• Antigen Targeting: Patents on antigens associated with colon and gastrointestinal cancers, such as CEA, TAG-72, and the 17-1A antigen.

• Antibody Engineering: Patents on humanization, affinity maturation, and conjugation of monoclonal antibodies initially derived from murine sources like 17-1A.

• Diagnostic Assays: Various patents address immunoassay formats, ELISA, and in vivo imaging using monoclonal antibodies.

Key Players

• Immuno-AG (Immuno-AG's patents cover the 17-1A antibody and derivatives).
• Cytogen (pioneered CEA-targeted antibodies).
• Schering-Plough (invested in antibody conjugates and diagnostics).
• Abbott Laboratories and Amgen (advanced antibody engineering and diagnostic patent portfolios).

Patent Term and Expiry

• Patent 5,208,256 was filed on Dec 3, 1987, and granted on May 4, 1993.
• Term typically runs 20 years from the filing date, thus expiring around Dec 3, 2007, unless extensions or adjustments apply.
• Expiry opens the patent to generic antibody development and biosimilar competition.

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Implications for Commercial Development and Infringement Risks

• The patent's expiration enables manufacturing biosimilar or generic-antibody products targeting colon cancer antigens.
• Existing patents on related antibodies, conjugation methods, or diagnostic kits may pose infringement risks in different jurisdictions.
• The scope is confined to antibodies specifically targeting the 17-1A antigen; alternative antibodies targeting the same antigen or different epitopes could avoid infringement.

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Legal and Innovation Trends in Monoclonal Antibodies for Cancer

• The evolution from murine to humanized or fully human antibodies has led to multiple new patents, often building on foundational patents like 5,208,256.
• Patent pools and licensing agreements facilitate access and reduce litigation risks for developers focusing on colon cancer diagnostics or therapies.
• The expiration of 5,208,256 grants more freedom to develop conjugates, biosimilars, and diagnostics based on the same antigen.

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Key Takeaways

• Patent 5,208,256 claims a monoclonal antibody specific to colon carcinoma antigen 17-1A, with broad diagnostic and therapeutic application claims.
• The patent landscape includes early antibody patents (e.g., 4,943,533), antigen targeting patents, and subsequent antibody engineering patents.
• Competitors frequently focus on similar antigens like CEA and TAG-72, with numerous patents covering assays, conjugates, and humanized antibodies.
• The patent's expiration in 2007 permits independent development of similar products, but multiple related patents could still restrict certain methods or conjugates.
• Market opportunities exist in diagnostic kits, antibody-drug conjugates, and therapeutic formulations, especially given the advancements in antibody engineering.

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FAQs

1. Does Patent 5,208,256 cover therapeutic uses of the 17-1A antibody?
Yes, it claims therapeutic applications, including targeting colon tumors. However, specific therapeutic formulations and conjugates may be covered under subsequent or separate patents filing later.

2. Are there active patents that limit development based on 17-1A today?
Major patents related to the original antibody expired, but patents on humanized versions, conjugates, and specific diagnostic methods from the 1990s onward could still pose restrictions.

3. How does the scope of the 5,208,256 patent compare to other antibody patents targeting colon cancer?
It concentrates on the 17-1A antibody and its use; in contrast, other patents target different antigens (e.g., CEA) or employ alternative antibody engineering approaches.

4. Can companies develop biosimilars of 17-1A now?
Yes, given the patent expiration, biosimilar development for the original murine antibody is legally permissible, but they must check for existing patents on specific conjugates or humanized variants.

5. What has been the trend in patenting around colon cancer antibodies since 2000?
There's been a shift toward humanized and fully human antibodies, conjugates with toxins or radioisotopes, and diagnostic imaging agents, with new patents focusing on improved efficacy and safety profiles.

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Citations

1. United States Patent 5,208,256, "Monoclonal antibody 17-1A," granted May 4, 1993.
2. United States Patent 4,943,533, "Monoclonal antibody to carcinoembryonic antigen," filed 1985.
3. European Patent 0318995, "Antibody compositions," Immuno-AG.
4. World Intellectual Property Organization (WO) Patent Application WO 91/10714, related to 17-1A antibody conjugates.

[1] Patent and literature review data sourced from USPTO, EPO, and WIPO databases.

Drugs Protected by US Patent 5,208,256

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate

Foreign Priority and PCT Information for Patent: 5,208,256

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Japan	2-132909	May 22, 1990

International Family Members for US Patent 5,208,256

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	114470
Canada	2042972
Germany	69105349
Denmark	0458588
European Patent Office	0458588
Japan	H04253910