United States Patent 5,601,838: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
The United States Patent 5,601,838, hereafter referred to as the '838 patent, is a significant intellectual property asset that has played a crucial role in the pharmaceutical industry, particularly in the context of the drug Lidoderm. This patent, along with others, has been central to the legal and commercial strategies of its holders. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this patent.
Background of the Patent
The '838 patent was granted on February 11, 1997, and is titled "Transdermal administration of local anesthetics using hydrogels." It is one of the key patents associated with Lidoderm, a transdermal patch used for the treatment of postherpetic neuralgia, a complication of shingles[1].
Scope of the Patent
The '838 patent covers the use of hydrogel transdermal patches for the administration of local anesthetics. Specifically, it describes a method and composition for delivering lidocaine through a hydrogel patch, which provides a controlled release of the anesthetic over an extended period. This technology is critical for the efficacy and safety of Lidoderm, as it ensures a consistent and predictable delivery of the active ingredient[1].
Claims of the Patent
The patent includes several claims that define the scope of the invention. These claims typically cover the composition of the hydrogel patch, the method of preparing it, and the specific use of lidocaine as the active ingredient. Here are some key aspects of the claims:
- Composition Claims: These claims specify the components of the hydrogel patch, including the type and amount of lidocaine, the hydrogel matrix, and any additional ingredients.
- Method Claims: These claims describe the process of preparing the hydrogel patch, including the steps involved in mixing the ingredients and forming the patch.
- Use Claims: These claims outline the intended use of the hydrogel patch, which is the transdermal administration of lidocaine for pain relief[1].
Patent Expiration and Impact
The '838 patent, along with another related patent (U.S. Patent No. 5,411,738), expired on May 2, 2012. This expiration marked a significant milestone, as it allowed generic manufacturers to begin the process of developing and marketing their own versions of Lidoderm. However, the expiration did not immediately open the market to generics due to other patent and regulatory hurdles[1].
Related Patents and Litigation
The '838 patent is part of a larger patent portfolio related to Lidoderm. Other patents, such as U.S. Patent No. 5,827,529 ('529 patent), played a role in extending the exclusivity period for Lidoderm. For instance, the '529 patent, which expired on October 17, 2015, was used to delay the approval of generic versions of Lidoderm through a Citizen Petition filed with the FDA. This petition sought to impose stricter bioequivalence requirements for generic versions, further protecting the brand-name product[1].
Litigation and Settlements
The '838 patent was also involved in litigation. For example, Endo Pharmaceuticals, the owner of Lidoderm, settled a lawsuit with LecTec Corporation in 2009, acquiring exclusive licenses to use certain patents (including U.S. Patent Nos. 5,741,510 and 5,536,263) in exchange for a $23 million payment. These patents were subsequently listed in the Orange Book for Lidoderm, further complicating the generic approval process[1].
Patent Landscape
The patent landscape surrounding the '838 patent is complex and involves multiple stakeholders and strategies.
Orange Book Listings
The Orange Book, officially known as the Approved Drug Products with Therapeutic Equivalence Evaluations, lists patents that are associated with approved drug products. The '838 patent, along with other related patents, was listed in the Orange Book for Lidoderm. This listing is crucial because it informs generic manufacturers about the patents they must address in their Abbreviated New Drug Applications (ANDAs)[1].
Citizen Petitions
Endo Pharmaceuticals used Citizen Petitions to influence the FDA's approval process for generic versions of Lidoderm. These petitions requested changes in the regulatory requirements for bioequivalence, aiming to make it more difficult for generics to enter the market[1].
Global Patent System
The global patent system, facilitated by initiatives like the Global Dossier and Common Citation Document (CCD), plays a significant role in managing patent families and prior art across different jurisdictions. This system helps in harmonizing patent searches and evaluations, ensuring that patents like the '838 patent are thoroughly examined for validity and scope on an international level[4].
Impact on the Pharmaceutical Industry
The '838 patent and its associated legal and regulatory strategies have had a profound impact on the pharmaceutical industry.
Market Exclusivity
The combination of patents and regulatory maneuvers extended the market exclusivity period for Lidoderm, allowing the brand-name product to maintain its market share for a longer period. This strategy is common in the pharmaceutical industry, where companies use multiple patents and regulatory filings to protect their products from generic competition[1].
Generic Competition
Despite the expiration of the '838 patent, the entry of generic versions of Lidoderm was delayed due to other patent and regulatory barriers. This delay highlights the complexities and challenges faced by generic manufacturers in bringing their products to market[1].
Expert Insights
Industry experts emphasize the importance of a robust patent strategy in the pharmaceutical sector. As noted by Alan C. Marco and Joshua D. Sarnoff in their work on patent claims and scope, "Patent claims are a critical component of the patent system, as they define the scope of the invention and determine the boundaries of the patentee's exclusive rights"[3].
Statistics and Economic Impact
The economic impact of patents like the '838 patent can be significant. For instance, Lidoderm generated substantial revenue for its owners, with sales revenue in the United States reaching $825 million in 2011 and $947 million in 2012[1].
Key Takeaways
- Patent Scope and Claims: The '838 patent covers the use of hydrogel transdermal patches for delivering lidocaine, with specific claims related to composition, method of preparation, and use.
- Patent Expiration and Impact: The patent expired on May 2, 2012, but its impact was extended through other patents and regulatory strategies.
- Related Patents and Litigation: The patent is part of a larger portfolio, and its holders engaged in litigation and settlements to protect their intellectual property.
- Global Patent Landscape: The global patent system plays a crucial role in managing patent families and prior art, affecting the validity and scope of patents internationally.
- Industry Impact: The patent and associated strategies significantly influenced the market exclusivity period for Lidoderm, impacting both the brand-name product and generic competition.
FAQs
What is the main subject of the '838 patent?
The '838 patent covers the transdermal administration of local anesthetics using hydrogel patches, specifically for delivering lidocaine.
When did the '838 patent expire?
The '838 patent expired on May 2, 2012.
How did the '838 patent impact the market for Lidoderm?
The patent, along with other related patents and regulatory strategies, extended the market exclusivity period for Lidoderm, delaying the entry of generic versions.
What role did Citizen Petitions play in protecting Lidoderm?
Citizen Petitions were used to request stricter bioequivalence requirements for generic versions of Lidoderm, further protecting the brand-name product.
How does the global patent system affect patents like the '838 patent?
The global patent system helps in harmonizing patent searches and evaluations across different jurisdictions, ensuring thorough examination of patents for validity and scope.
Sources
- USCOURTS-cand-3_14-md-02521: Complaints and filings related to Lidoderm patents.
- Unified Patents: Patent data for US-5601838-A.
- USPTO: Patent Claims Research Dataset and related documentation.
- USPTO: Search for patents and global patent system services.
- PubChem: Information on patent US-8535692-B2.
