WRITTEN DESCRIPTION IN LIFE SCIENCES PATENTS: AVOIDING OVERREACH
EMPOWERING INDIVIDUALS TO MAKE THE BEST DECISIONS WHEN CONSIDERING THEIR INTELLECTUAL PROPERTY RIGHTS
The written description requirement is a critical and often contentious issue in life sciences patent law. In biotechnology and pharmaceutical patents, meeting this requirement can be challenging due to the complexity and unpredictability of biological inventions. Because courts and patent offices worldwide continue to refine what is necessary to satisfy written description obligations, it is crucial for inventors and practitioners to stay informed. WRITTEN DESCRIPTION IN LIFE SCIENCES PATENTS: AVOIDING OVERREACH
Under 35 U.S.C. § 112(a) , a patent must contain a written description of the invention that is sufficient to demonstrate that the inventor had possession of the claimed invention at the time of filing. This requirement ensures that an applicant does not claim more than what was actually invented and disclosed. UNDERSTANDING THE WRITTEN DESCRIPTION REQUIREMENTS
In biotech and pharmaceutical patents , the challenge lies in describing biological molecules, genetic sequences and complex therapeutic mechanisms with enough specificity.
THE SCOPE OF GENUS CLAIMS The Supreme Court's recent ruling in Amgen v. Sanofi reinforced the difficulty of securing broad genus claims in biotech patents. The case centered on Amgen's patents covering monoclonal antibodies that inhibit PCSK9, a target for lowering cholesterol. The Court found that Amgen's patent did not provide sufficient guidance for how to make and use all claimed antibodies, highlighting that merely describing a few examples is often insufficient for the written description and enablement; thus, the patent was held invalid.
GUIDING CASE LAW
AMGEN V. SANOFI (2023)
THE DECISION: THE SCOPE OF GENUS CLAIMS
AMGEN V. SANOFI (2023) GUIDING CASE LAW
This decision emphasizes the importance of structural
characterization and representative species in biotech patent applications. Simply claiming a function (e.g., "antibodies that bind to PCSK9") without providing a diverse set of well- characterized embodiments can doom a patent's validity.
THE NEED FOR REPRESENTATIVE EXAMPLES In Juno Therapeutics v. Kite Pharma, the U.S. Court of Appeals for the Federal Circuit invalidated a CAR-T cell therapy patent due to an insufficient written description. The patent broadly claimed a genus of chimeric antigen receptors, but the court found that the application failed to provide enough representative species or structural details to justify such broad claims. This decision reaffirmed that for biotechnology inventions, a few examples may not be enough — applicants must disclose a range of embodiments to support a broad claim.
GUIDING CASE LAW
JUNO THERAPEUTICS V. KITE PHARMA (2021)
BEST PRACTICES FOR SATISFYING THE WRITTEN DESCRIPTION REQUIREMENTS IN BIOTECH PATENTS
Given the evolving case law, life sciences patent applicants should consider the following strategies to strengthen their written description compliance:
PROVIDE STRUCTURAL DETAIL ...
Provide Structural Detail, Not Just Functionality: Avoid relying solely on functional language (e.g., "a molecule that inhibits enzyme X"). Instead, describe specific structures, sequences or formulations that achieve the function.
INCLUDE REPRESENTATIVE SPECIES
Include Representative Species: If seeking broad genus claims (e.g., for a class of antibodies or gene edits), disclose multiple representative examples covering structural variations.
USE DEPOSITS AND SEQUENCE LISTINGS WHERE APPROPRIATE
Use Deposits and Sequence Listings Where Appropriate: For biological materials, depositing strains, plasmids or cell lines in recognized repositories, such as ATCC, can help meet the written description requirement.
INCORPORATE EXPERIMENTAL DATA Incorporate Experimental Data: Experimental results demonstrating that the described embodiments work as claimed can bolster written description arguments.
ALIGN CLAIM SCOPE WITH DISCLOSURE
Align Claim Scope With Disclosure: Draft claims that correspond to the level of detail in the specification to avoid overreach. If a patent claims an entire class of molecules, the application should describe sufficient examples to justify the breadth.
CONTRIBUTORS
Dr. Erica A. Fishel is an associate at Day Pitney and advises clients on a range of intellectual property matters, including licensing agreements, patent prosecution, developing intellectual property portfolio strategies, crafting patent claim strategies, and preparing patent applications. efishel@daypitney.com Dr. Christopher R. Cowles is a partner at Day Pitney and advises intellectual property owners, inventors, and academic institutions on building and maximizing biotech assets. He focuses on patent preparation, legal opinions, patent disputes, and diligence for partnerships, funding, and mergers and acquisitions. ccowles@daypitney.com
Our Intellectual Property and Technology Group Every day, Day Pitney intellectual property attorneys help clients acquire, secure, transfer, defend, enforce and understand their intellectual property rights. We prosecute patents and trademarks; negotiate and draft agreements for the license and sale of intellectual property rights; litigate intellectual property disputes in federal and state courts around the country, including before the International Trade Commission (ITC) and the U.S. Patent and Trademark Office; and advise clients on the entire array of evolving intellectual property issues modern businesses confront, including workplace policies relating to Internet access and use, social media, and privacy.
Emily Ferriter Russo, an associate at Day Pitney, started Patently Enabled , because she believes in empowering individuals to make the best decisions when considering their intellectual property rights. eferriterrusso@daypitney.com
Thank you for considering this post, which is a general summary meant to reduce complex issues for general practitioners and inventors. It is not intended to be exhaustive by any means. For any comments, questions, or other inquiries, please contact registered patent attorney George Chaclas at Day Pitney LLP. This communication is provided for educational and informational purposes only and is not intended and should not be construed as legal advice, nor does its distribution or receipt create an attorney-client relationship. This communication may be deemed advertising under applicable state laws. Prior results do not guarantee a similar outcome. If you have any questions regarding this communication, please contact Day Pitney LLP at 605 Third Avenue, 31st Floor, New York, NY 10158, (212) 297 5800.
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