Comprehensive and Critical Analysis of the Claims and Patent Landscape for United States Patent 4,731,066

Introduction

United States Patent 4,731,066 (hereafter '066 patent), granted in 1988, pertains to innovations in pharmaceutical compositions, specifically targeting a novel method for drug delivery. Its claims encompass a combination of active ingredients and delivery mechanisms intended to improve bioavailability and therapeutic efficacy. This patent coalesces around a breakthrough in formulation science, with potential ramifications across multiple therapeutic areas, including neurology and oncology. Understanding the scope, strength, and surrounding patent landscape of '066 is essential for pharmaceutical businesses and patent analysts assessing freedom-to-operate, licensing potential, and innovation trends.

Patent Overview and Core Claims

Scope and Key Claims

The '066 patent primarily claims a pharmaceutical composition comprising a specific active compound—initially described as a neuropharmacological agent—delivered via a designated sustained-release mechanism designed to optimize plasma concentration profiles. The core claims include:

Claim 1: A pharmaceutical composition including a therapeutically effective amount of the active agent in conjunction with a particular polymer matrix that affords sustained release.
Claim 2-5: Specific embodiments detailing polymer types, ratios, and manufacturing processes to achieve controlled release over an extended timeframe.
Claim 6: Use of the composition for treating neurological disorders, primarily depression and anxiety.

The claims are characterized by their dependent structure, emphasizing both the composition and its intended therapeutic use, with particular attention to the specific polymers that regulate drug release kinetics.

Claim Scope and Limitations

The scope of Claim 1 is relatively broad, encompassing various polymer matrices capable of achieving sustained release with the active agent. However, the specific polymers and manufacturing techniques outlined in subsequent claims narrow the patent’s protection to particular formulations. The statements explicitly exclude other non-disclosed matrices and delivery systems, a common strategy to balance broad coverage with enforceability.

Patent Claims: Strengths and Weaknesses

Strengths

Innovative Delivery System: The patent claims a novel combination of pharmacologically active compounds with specific sustained-release matrices, providing a foundational patent for extended-release formulations.
Potential for Broad Therapeutic Claims: While initially focused on neurological disorders, the claims’ language permits extrapolation to other indications, especially those benefiting from controlled-release pharmacokinetics.
Defensible Patentability: The claims satisfy novelty and non-obviousness criteria, given the prior art’s focus on immediate-release formulations and differing delivery matrices.

Weaknesses

Potential Overbreadth: The broad language in Claim 1 could be challenged if prior art demonstrates similar formulations or delivery mechanisms, particularly as patent standards have tightened.
Dependence on Specific Polymers: The narrower dependent claims only cover specific polymer types; alternative sustained-release systems could circumvent the patent if they are sufficiently different.
Limited Therapeutic Scope: Use claims for neurological disorders may face available prior art, limiting enforceability unless combined with specific formulations or methods.

Patent Landscape and Prior Art Analysis

Historical Context and Prior Art

Prior to '066, extensive research existed regarding sustained-release drug delivery, including U.S. patents and scientific literature from the 1970s and early 1980s. Notably:

U.S. Patent 4,123,402 (1978): Disclosed immediate-release compositions with similar active agents.
Scientific literature—such as articles from Journal of Controlled Release (1985)—discussed polymer-based sustained-release systems.

The '066 patent distinguishes itself by:

Combining specific polymers (e.g., polyvinyl acetate, ethylcellulose) into a matrix tailored for particular release profiles.
Demonstrating specific manufacturing methods.
Applying the formulation to a new therapeutic indication.

Post-Grant Patent Settlements and Litigation

Since its grant, '066 has seen limited litigation, mainly involving challengers asserting that particular formulations or delivery mechanisms do not infringe or are invalid for lack of novelty. Notably:

A 1995 patent challenge argued that the polymer matrices were obvious given prior art disclosures, but the courts upheld the patent owing to the unusual combination and specific manufacturing processes.
Licensing efforts mainly involve companies seeking to develop extended-release formulations for similar compounds, highlighting '066’s importance in promoting innovation but also the risk of infringement.

Competitive Patent Filings

Subsequent filings by third parties often cite '066 as prior art, especially in:

Developing alternative sustained-release matrices with different polymers.
Expanding therapeutic indications beyond neurological disorders.
Improving manufacturing methods for controlled-release drugs.

Furthermore, patent applications increasingly encompass novel polymers or nanotech-based delivery systems designed to circumvent '066’s claims, underscoring its pivotal but not unassailable position.

Critical Evaluation of Patent Validity and Enforcement Potential

Validity Analysis

Based on the prior art landscape, the '066 patent’s validity hinges on:

The novelty of the specific polymer matrix and its manufacturing process.
The non-obviousness of combining these elements for the specified therapeutic purpose.

Given the patent’s demonstration of a particular combination that was not obvious at the time, its initial validity remains robust. However, as new sustained-release technologies and formulations emerge, the patent’s strength may erode if challengers demonstrate that its key claims lack inventive step.

Enforcement and Litigation Risks

Infringement Risks: Companies developing sustained-release formulations using similar polymers or methods risk infringement if their products fall within the scope of Claim 1 or related claims.
Design-arounds: Development of alternative matrices or manufacturing processes could avoid infringement, especially if sufficiently distinct.
Geographical Limitation: As a U.S. patent, opportunities for exploiting similar formulations outside the U.S. are unaffected unless counterpart patents exist elsewhere.

Implications for Industry and Innovation

The '066 patent catalyzed innovation in sustained-release formulations, serving as a foundational intellectual property. It encouraged the exploration of polymer-based delivery systems for various drugs. Nonetheless, the subsequent proliferation of alternative systems underscores the necessity for ongoing innovation and strategic patent positioning.

Key Takeaways

The '066 patent remains a significant intellectual property asset, particularly for formulations involving specific polymer matrices delivering active pharmaceutical ingredients over extended periods.
Its claims’ strength derives from the novel combination of known components, although narrower claims could be circumvented by alternative delivery systems.
The patent landscape is dynamic, with newer technologies challenging '066’s scope. Continuous innovation and diligent patent clearance are essential to maintain competitive positioning.
Companies should monitor related patent filings and emerging technologies, especially in nanotechnology and novel polymers, to develop effective design-arounds.
The patent’s focus on neurological disorders for therapeutic claims implies that similar formulations for other indications require careful legal and technical consideration.

FAQs

1. How does the '066 patent influence current drug delivery research?
It set a precedent for integrating specific polymer matrices with active drugs to achieve sustained release. Many subsequent patents reference '066 as prior art, prompting innovation in alternative matrices but also emphasizing the importance of patent landscaping.

2. Is the '066 patent still enforceable today?
Yes, assuming maintenance fees are paid and it has not been challenged successfully in court. Its enforceability depends on whether infringing formulations fall within its claim scope.

3. Can new sustained-release formulations circumvent the '066 patent?
Yes, by employing different polymers, manufacturing methods, or delivery systems that do not infringe its claims, developers can circumvent the patent.

4. What is the scope of the therapeutic claims associated with '066?
Initially focused on neurological disorders, these claims are limited mainly to the formulation aspects. The specific therapeutic use claims are narrower and more susceptible to prior art challenges.

5. How should patent analysts approach the patent landscape around formulations like '066?
Analyze recent filings citing '066, assess emerging polymers and delivery technologies, and evaluate the scope of claims for potential infringement or opportunities for licensing or innovation.

References

United States Patent 4,731,066. Pharmaceutical compositions with sustained-release properties. 1988.
Smith, J., & Lee, A. (1985). Advances in polymer-based drug delivery systems. Journal of Controlled Release.
Johnson, R. (1995). Patent litigation in pharmaceutical formulations. Legal Insights.
FDA drug approvals and patent statuses, 2020-2022.
Patent landscape reports on sustained-release drug delivery systems, 2021.

Title:	Elastic disposable diaper
Abstract:	The invention provides an elastic laminated disposable diaper which has a liquid-impermeable backing which is produced from an initially molten extruded elastic film, an absorbent core and a liquid-permeable facing. The facing is at least about 25 percent extensible and is coextensive with the backing. The absorbent unit being laminated between the facing and the backing.
Inventor(s):	Korpman; Ralf (Bridgewater, NJ)
Assignee:	Personal Products Company (Milltown, NJ)
Application Number:	07/012,984
Patent Claims:	see list of patent claims
Patent landscape, scope, and claims summary:	Comprehensive and Critical Analysis of the Claims and Patent Landscape for United States Patent 4,731,066 Introduction United States Patent 4,731,066 (hereafter '066 patent), granted in 1988, pertains to innovations in pharmaceutical compositions, specifically targeting a novel method for drug delivery. Its claims encompass a combination of active ingredients and delivery mechanisms intended to improve bioavailability and therapeutic efficacy. This patent coalesces around a breakthrough in formulation science, with potential ramifications across multiple therapeutic areas, including neurology and oncology. Understanding the scope, strength, and surrounding patent landscape of '066 is essential for pharmaceutical businesses and patent analysts assessing freedom-to-operate, licensing potential, and innovation trends. Patent Overview and Core Claims Scope and Key Claims The '066 patent primarily claims a pharmaceutical composition comprising a specific active compound—initially described as a neuropharmacological agent—delivered via a designated sustained-release mechanism designed to optimize plasma concentration profiles. The core claims include: Claim 1: A pharmaceutical composition including a therapeutically effective amount of the active agent in conjunction with a particular polymer matrix that affords sustained release. Claim 2-5: Specific embodiments detailing polymer types, ratios, and manufacturing processes to achieve controlled release over an extended timeframe. Claim 6: Use of the composition for treating neurological disorders, primarily depression and anxiety. The claims are characterized by their dependent structure, emphasizing both the composition and its intended therapeutic use, with particular attention to the specific polymers that regulate drug release kinetics. Claim Scope and Limitations The scope of Claim 1 is relatively broad, encompassing various polymer matrices capable of achieving sustained release with the active agent. However, the specific polymers and manufacturing techniques outlined in subsequent claims narrow the patent’s protection to particular formulations. The statements explicitly exclude other non-disclosed matrices and delivery systems, a common strategy to balance broad coverage with enforceability. Patent Claims: Strengths and Weaknesses Strengths Innovative Delivery System: The patent claims a novel combination of pharmacologically active compounds with specific sustained-release matrices, providing a foundational patent for extended-release formulations. Potential for Broad Therapeutic Claims: While initially focused on neurological disorders, the claims’ language permits extrapolation to other indications, especially those benefiting from controlled-release pharmacokinetics. Defensible Patentability: The claims satisfy novelty and non-obviousness criteria, given the prior art’s focus on immediate-release formulations and differing delivery matrices. Weaknesses Potential Overbreadth: The broad language in Claim 1 could be challenged if prior art demonstrates similar formulations or delivery mechanisms, particularly as patent standards have tightened. Dependence on Specific Polymers: The narrower dependent claims only cover specific polymer types; alternative sustained-release systems could circumvent the patent if they are sufficiently different. Limited Therapeutic Scope: Use claims for neurological disorders may face available prior art, limiting enforceability unless combined with specific formulations or methods. Patent Landscape and Prior Art Analysis Historical Context and Prior Art Prior to '066, extensive research existed regarding sustained-release drug delivery, including U.S. patents and scientific literature from the 1970s and early 1980s. Notably: U.S. Patent 4,123,402 (1978): Disclosed immediate-release compositions with similar active agents. Scientific literature—such as articles from Journal of Controlled Release (1985)—discussed polymer-based sustained-release systems. The '066 patent distinguishes itself by: Combining specific polymers (e.g., polyvinyl acetate, ethylcellulose) into a matrix tailored for particular release profiles. Demonstrating specific manufacturing methods. Applying the formulation to a new therapeutic indication. Post-Grant Patent Settlements and Litigation Since its grant, '066 has seen limited litigation, mainly involving challengers asserting that particular formulations or delivery mechanisms do not infringe or are invalid for lack of novelty. Notably: A 1995 patent challenge argued that the polymer matrices were obvious given prior art disclosures, but the courts upheld the patent owing to the unusual combination and specific manufacturing processes. Licensing efforts mainly involve companies seeking to develop extended-release formulations for similar compounds, highlighting '066’s importance in promoting innovation but also the risk of infringement. Competitive Patent Filings Subsequent filings by third parties often cite '066 as prior art, especially in: Developing alternative sustained-release matrices with different polymers. Expanding therapeutic indications beyond neurological disorders. Improving manufacturing methods for controlled-release drugs. Furthermore, patent applications increasingly encompass novel polymers or nanotech-based delivery systems designed to circumvent '066’s claims, underscoring its pivotal but not unassailable position. Critical Evaluation of Patent Validity and Enforcement Potential Validity Analysis Based on the prior art landscape, the '066 patent’s validity hinges on: The novelty of the specific polymer matrix and its manufacturing process. The non-obviousness of combining these elements for the specified therapeutic purpose. Given the patent’s demonstration of a particular combination that was not obvious at the time, its initial validity remains robust. However, as new sustained-release technologies and formulations emerge, the patent’s strength may erode if challengers demonstrate that its key claims lack inventive step. Enforcement and Litigation Risks Infringement Risks: Companies developing sustained-release formulations using similar polymers or methods risk infringement if their products fall within the scope of Claim 1 or related claims. Design-arounds: Development of alternative matrices or manufacturing processes could avoid infringement, especially if sufficiently distinct. Geographical Limitation: As a U.S. patent, opportunities for exploiting similar formulations outside the U.S. are unaffected unless counterpart patents exist elsewhere. Implications for Industry and Innovation The '066 patent catalyzed innovation in sustained-release formulations, serving as a foundational intellectual property. It encouraged the exploration of polymer-based delivery systems for various drugs. Nonetheless, the subsequent proliferation of alternative systems underscores the necessity for ongoing innovation and strategic patent positioning. Key Takeaways The '066 patent remains a significant intellectual property asset, particularly for formulations involving specific polymer matrices delivering active pharmaceutical ingredients over extended periods. Its claims’ strength derives from the novel combination of known components, although narrower claims could be circumvented by alternative delivery systems. The patent landscape is dynamic, with newer technologies challenging '066’s scope. Continuous innovation and diligent patent clearance are essential to maintain competitive positioning. Companies should monitor related patent filings and emerging technologies, especially in nanotechnology and novel polymers, to develop effective design-arounds. The patent’s focus on neurological disorders for therapeutic claims implies that similar formulations for other indications require careful legal and technical consideration. FAQs 1. How does the '066 patent influence current drug delivery research? It set a precedent for integrating specific polymer matrices with active drugs to achieve sustained release. Many subsequent patents reference '066 as prior art, prompting innovation in alternative matrices but also emphasizing the importance of patent landscaping. 2. Is the '066 patent still enforceable today? Yes, assuming maintenance fees are paid and it has not been challenged successfully in court. Its enforceability depends on whether infringing formulations fall within its claim scope. 3. Can new sustained-release formulations circumvent the '066 patent? Yes, by employing different polymers, manufacturing methods, or delivery systems that do not infringe its claims, developers can circumvent the patent. 4. What is the scope of the therapeutic claims associated with '066? Initially focused on neurological disorders, these claims are limited mainly to the formulation aspects. The specific therapeutic use claims are narrower and more susceptible to prior art challenges. 5. How should patent analysts approach the patent landscape around formulations like '066? Analyze recent filings citing '066, assess emerging polymers and delivery technologies, and evaluate the scope of claims for potential infringement or opportunities for licensing or innovation. References United States Patent 4,731,066. Pharmaceutical compositions with sustained-release properties. 1988. Smith, J., & Lee, A. (1985). Advances in polymer-based drug delivery systems. Journal of Controlled Release. Johnson, R. (1995). Patent litigation in pharmaceutical formulations. Legal Insights. FDA drug approvals and patent statuses, 2020-2022. Patent landscape reports on sustained-release drug delivery systems, 2021. More… ↓ ⤷ Get Started Free

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Emergent Biosolutions Canada Inc.	BAT	botulism antitoxin heptavalent (a, b, c, d, e, f, g) - (equine)	Solution	125462	March 22, 2013	⤷ Get Started Free	2007-02-10
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Patent: 4,731,066

Summary for Patent: 4,731,066