United States Patent 8,071,075: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 8,071,075, titled "Dermal penetration enhancers and drug delivery systems involving the same," is a significant patent in the field of pharmaceuticals, particularly in the development of transdermal drug delivery systems. This patent, issued on December 6, 2011, to inventors Barry Leonard Reed, Timothy Mathias Morgan, and Barrie Charles Finnin, and assigned to Acrux DDS Pty Ltd., plays a crucial role in the treatment and prophylaxis of various conditions using dermal penetration enhancers.
Patent Background
The '075 patent is part of a series of patent applications and continuations, tracing back to an Australian Provisional Patent Application No. 8144 filed on February 19, 1996. It is also linked to other U.S. patents such as U.S. Patent No. 6,299,900, U.S. Patent No. 6,818,226, and U.S. Patent No. 7,438,203, through a chain of continuations and divisional applications[1][4].
Claims and Scope
The patent includes 13 claims, with claim 13 being the focal point of several legal disputes. Here is a breakdown of the key claims:
Claim 13
Claim 13 of the '075 patent describes a transdermal drug delivery system comprising:
- A therapeutically effective amount of testosterone.
- At least one dermal penetration enhancer present in an amount of from 10 to 10,000 wt% based on the weight of the testosterone.
- The dermal penetration enhancer is at least one ester of a specific formula[1].
This claim is critical as it defines the specific composition and method of the drug delivery system, which is central to the patent's validity and infringement disputes.
Patent Scope and Metrics
The scope of the '075 patent can be analyzed using metrics such as independent claim length and independent claim count. Research suggests that narrower claims, as measured by these metrics, are associated with a higher probability of grant and a shorter examination process. The examination process often narrows the scope of patent claims, making them more specific and less broad[3].
Independent Claim Length and Count
The '075 patent has 13 claims, with claim 13 being particularly detailed. The length and specificity of these claims indicate a focused scope, which is consistent with the trend that narrower claims are more likely to be granted and less likely to face validity challenges.
Legal Disputes and Validity
The '075 patent has been involved in several legal disputes, particularly in the context of generic drug manufacturers seeking to produce similar transdermal testosterone products.
Infringement and Validity Challenges
In the case of Eli Lilly & Co. v. Perrigo Co., claim 13 of the '075 patent was challenged for lack of written description and enablement. The court ultimately held that claim 13 was invalid for these reasons[1][5].
Priority Date Disputes
There was also a dispute over the priority date of the '075 patent, with Actavis challenging the claimed priority date of February 19, 1996. However, this issue was not definitively resolved as it did not affect the written description and enablement analysis[1].
Patent Landscape
The '075 patent is part of a broader landscape of patents related to transdermal drug delivery systems and dermal penetration enhancers.
Related Patents
Other patents listed in the Orange Book for Eli Lilly's Axiron® product, such as U.S. Patent Nos. 6,299,900, 6,818,226, and 8,993,520, are also relevant. These patents cover various aspects of the formulation, application, and delivery system of transdermal testosterone products[1].
Industry Impact
The '075 patent and related patents have significant implications for the pharmaceutical industry, particularly in the development and marketing of generic versions of transdermal testosterone products. The validity and scope of these patents can affect the timing and cost of bringing generic products to market.
Expert Insights and Statistics
Industry experts emphasize the importance of patent scope and validity in pharmaceutical innovation. For instance, narrower and more specific claims can reduce litigation costs and encourage innovation by providing clearer boundaries for competitors[3].
Illustrative Statistics
Research indicates that patents with narrower claims have a higher grant rate (around 70%) compared to those with broader claims (around 40%)[3]. This highlights the strategic importance of claim drafting in patent applications.
Conclusion and Key Takeaways
- Patent Scope and Claims: The '075 patent has a focused scope with 13 claims, particularly claim 13, which defines a specific transdermal drug delivery system.
- Legal Disputes: The patent faced challenges for lack of written description and enablement, leading to the invalidation of claim 13.
- Patent Landscape: The '075 patent is part of a broader landscape of patents related to transdermal drug delivery systems and dermal penetration enhancers.
- Industry Impact: The validity and scope of this patent significantly affect the development and marketing of generic transdermal testosterone products.
- Expert Insights: Narrower and more specific claims are associated with higher grant rates and reduced litigation costs.
Key Takeaways
- The '075 patent's scope is defined by its specific claims, particularly claim 13.
- Legal disputes have highlighted the importance of written description and enablement in patent validity.
- The patent landscape for transdermal drug delivery systems is complex and involves multiple related patents.
- The industry impact of patent validity and scope is significant, affecting the timing and cost of generic product development.
- Narrower claims are generally preferred for their clarity and reduced litigation risk.
FAQs
What is the main subject of United States Patent 8,071,075?
The main subject of the '075 patent is dermal penetration enhancers and drug delivery systems, specifically for the delivery of testosterone.
What is claim 13 of the '075 patent?
Claim 13 describes a transdermal drug delivery system comprising a therapeutically effective amount of testosterone and at least one dermal penetration enhancer in a specific amount and formula.
Why was claim 13 of the '075 patent invalidated?
Claim 13 was invalidated due to lack of written description and enablement.
What is the significance of the priority date dispute in the '075 patent?
The priority date dispute was relevant for determining the prior art but did not affect the written description and enablement analysis.
How does the '075 patent impact the pharmaceutical industry?
The '075 patent affects the development and marketing of generic transdermal testosterone products by defining the boundaries of what is considered infringing and valid.
Cited Sources
- Eli Lilly & Co. v. Perrigo Co. - Casetext
- US8071075B2 - Unified Patents Portal
- Patent Claims and Patent Scope - SSRN
- US8071075B2 - Dermal penetration enhancers and drug delivery systems involving the same - Google Patents
- Eli Lilly & Co. v. Perrigo Co. - Robins Kaplan LLP Law
