United States Patent 9,815,827: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
The United States Patent 9,815,827, hereafter referred to as the '827 patent, is a method of use patent related to the proprietary atypical antipsychotic agent LATUDA® (lurasidone HCl tablets), developed and marketed by Sumitomo Dainippon Pharma Co., Ltd. and its U.S. subsidiary, Sunovion Pharmaceuticals Inc. This article delves into the scope, claims, and the evolving patent landscape surrounding this patent.
Background of LATUDA®
LATUDA® is an atypical antipsychotic agent with a unique chemical structure, approved by the FDA and marketed in the U.S. since February 2011. It is used primarily for the treatment of schizophrenia and bipolar depression[5].
Patent Claims and Scope
The '827 patent encompasses a method of use for lurasidone HCl tablets, specifically focusing on the method's efficacy without causing a clinically significant weight gain.
Claim Construction
The claim construction of the '827 patent has been a subject of significant debate. The patent includes terms such as "without a clinically significant weight gain" or "without a weight gain." The plaintiffs, Sumitomo Dainippon Pharma Co., Ltd. and Sunovion Pharmaceuticals Inc., initially argued that these terms did not limit the claims. However, they later conceded that these terms are indeed claim limitations[4].
Interpretation of Key Terms
The court's interpretation of key terms in the '827 patent is crucial. The term "a patient" was a point of contention, with plaintiffs arguing it should be construed to mean "a patient population." However, the court found that the specification of the '827 patent does not support this interpretation. Instead, the court determined that "a patient" refers to an individual patient rather than a population[4].
Patent Infringement Litigation
The '827 patent has been at the center of several patent infringement lawsuits. When generic pharmaceutical companies, such as Piramal Healthcare UK Limited, filed Abbreviated New Drug Applications (ANDAs) for lurasidone HCl tablets, they included Paragraph IV certifications stating that the '827 patent is invalid, unenforceable, and/or will not be infringed by their ANDA products[2].
Sumitomo Dainippon Pharma Co. v. Piramal Healthcare UK Limited
In this case, Sumitomo Dainippon Pharma Co., Ltd. and Sunovion Pharmaceuticals Inc. filed a lawsuit against Piramal, alleging infringement of the '827 patent. The lawsuit highlighted the complexities of patent litigation, particularly in the pharmaceutical sector, where generic manufacturers often challenge the validity and enforceability of patents to expedite market entry[2].
Inter Partes Review (IPR)
A significant development in the patent landscape of the '827 patent was the Inter Partes Review (IPR) initiated by Slayback Pharma LLC. The USPTO's Patent Trial and Appeal Board (PTAB) held all 75 claims of the '827 patent to be unpatentable for obviousness over a single prior-art reference, U.S. Patent No. 5,532,372 (Saji)[1][5].
PTAB's Decision
The PTAB's decision was based on the construction of key terms and the evaluation of prior art. The Board construed "a patient" to have its ordinary and customary meaning of "one or more patients," as opposed to a "patient population." This construction played a critical role in determining the obviousness of the claims[1].
Sumitomo Dainippon Pharma's Response
Following the PTAB's decision, Sumitomo Dainippon Pharma announced its intention to seek revocation of the decision via a petition to the USPTO Director and/or an appeal to the United States Court of Appeals for the Federal Circuit (CAFC). The company remains committed to protecting the patent rights for LATUDA®[5].
Impact on Generic Entry
The IPR decision and subsequent litigation have significant implications for generic entry into the market. Despite the PTAB's ruling, Sumitomo Dainippon Pharma has settled disputes with several generic companies, allowing them to distribute their generic versions of lurasidone HCl starting on February 20, 2023[5].
Metrics for Measuring Patent Scope
The scope of the '827 patent can be analyzed using metrics such as independent claim length and independent claim count. These metrics help in understanding the breadth and clarity of patent claims. Narrower claims, as seen in the '827 patent after the IPR process, are often associated with a higher probability of grant and a shorter examination process[3].
Conclusion
The '827 patent represents a complex case in the pharmaceutical patent landscape, involving intricate claim constructions, IPR proceedings, and litigation. The patent's validity and enforceability have been challenged, leading to significant implications for both the innovator company and generic manufacturers.
Key Takeaways
- Claim Construction: The '827 patent's claims, particularly the term "a patient," have been subject to detailed interpretation.
- IPR Decision: The PTAB held all claims of the '827 patent unpatentable for obviousness.
- Litigation: Ongoing litigation and settlements have shaped the timeline for generic entry.
- Patent Scope Metrics: Independent claim length and count are useful metrics for assessing patent scope.
- Impact on Generic Entry: The patent landscape has been influenced by IPR decisions and litigation outcomes.
FAQs
Q: What is the '827 patent related to?
The '827 patent is related to the method of use for lurasidone HCl tablets, specifically the atypical antipsychotic agent LATUDA®.
Q: What was the outcome of the IPR proceeding for the '827 patent?
The PTAB held all 75 claims of the '827 patent to be unpatentable for obviousness over a single prior-art reference.
Q: How has Sumitomo Dainippon Pharma responded to the IPR decision?
Sumitomo Dainippon Pharma plans to seek revocation of the decision via a petition to the USPTO Director and/or an appeal to the CAFC.
Q: What is the current status of generic entry for lurasidone HCl tablets?
Generic companies are permitted to distribute their generic versions of lurasidone HCl starting on February 20, 2023, based on settlement agreements.
Q: What metrics are used to measure the scope of patent claims like those in the '827 patent?
Metrics such as independent claim length and independent claim count are used to measure the scope and clarity of patent claims.
Sources
- Sumitomo Pharma Co. v. Vidal, U.S. Court of Appeals for the Federal Circuit, No. 22-2276, April 5, 2024.
- Sumitomo Dainippon Pharma Co., Ltd. and Sunovion Pharmaceuticals Inc. v. Piramal Healthcare UK Limited, U.S. District Court for the District of New Jersey, Case No. 2:18-cv-13478-SRC-CLW.
- Patent Claims and Patent Scope, Hoover Institution, January 2016.
- Sumitomo Dainippon Pharma Co. v. Emcure Pharms. Ltd., U.S. District Court, October 5, 2018.
- Notice of the Decision of USPTO on Inter Partes Review (IPR) Proceeding for Method of Use Patent of LATUDA, Sumitomo Dainippon Pharma Co., Ltd., December 9, 2021.
