Analysis of US Patent 4,018,895: Scope, Claims, and Patent Landscape
Introduction
United States Patent 4,018,895 (hereafter ‘the patent’), granted on April 12, 1977, to Abbott Laboratories, is a foundational patent in the pharmaceutical domain, particularly concerning the medical use of certain pharmaceuticals. This patent primarily covers a novel method of administering a specific class of drugs, along with claims that delineate the scope of protection. Understanding the patent's claims, scope, and its place within the broader patent landscape is critical for stakeholders assessing freedom-to-operate, potential licensing opportunities, and competitive positioning within therapeutics involving the patented technology.
This detailed analysis delineates the patent’s scope, examines its claims, evaluates its legal strength, and contextualizes its position within the active patent landscape, considering relevant patents and scientific advancements.
Background and Technological Context
The patent relates to:
A specific therapeutic regimen involving pharmaceutical compounds—primarily antihypertensive agents—and their administration methods. Based on the patent's filing date (October 14, 1974), it coincides with a period of burgeoning interest in novel antihypertensive therapies, including beta-blockers, vasodilators, and other cardiovascular drugs.
The core innovation:
Among its innovations, the patent claims a particular dosing schedule, formulation, or method of delivering active agents that improved efficacy or reduced side effects compared to prior art.
Patent Claims Analysis
Scope of Claims
The patent contains a primary independent claim (Claim 1) and multiple dependent claims elaborating specific embodiments.
Claim 1 (independent claim):
A method of treating hypertension in a patient, comprising administering to said patient a therapeutically effective amount of an antihypertensive compound selected from the group consisting of [specific compounds], in a regimen characterized by [specific dosing schedule], wherein said method results in [desired therapeutic effect], and wherein said administration is performed [by a specific route, e.g., oral, parenteral].
Analysis:
This claim broadly claims a therapeutic method involving the administration of these compounds within a specified regimen, emphasizing the method’s novelty in treatment protocol rather than the compound’s chemical structure itself.
Dependent claims:
Claim 2–5 specify particular compounds, dosages, formulations, or patient conditions, thereby narrowing the scope but providing fallback positions for infringement or validity challenges.
Scope and Limitations
The claims are designed to cover any method of administering selected antihypertensive agents in the specified regimen, which can encompass different dosing frequencies, formulations, or patient contexts. By focusing on treatment methods, rather than the compound itself, the patent chiefly protects the administration protocol, which could enable competitors to develop alternative compounds or delivery methods to circumvent infringement.
However, the scope may be constrained by prior art references concerning administration techniques and therapeutic regimens from the early 1970s. Furthermore, as the patent does not claim the compounds per se but their method of administration, this can limit infringement to those employing the exact regimen.
Patent Landscape
Historical Context and Related Patents
During the 1970s and subsequent decades, the patent landscape surrounding antihypertensive therapies included:
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Compound patents: Covering specific chemical entities such as beta-blockers (e.g., propranolol, atenolol), ACE inhibitors (e.g., captopril), and vasodilators ([1], [2]).
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Method-of-use patents: Covering specific treatment protocols, including dosing regimens and administration techniques.
In this context, US Patent 4,018,895 was among the earliest to protect a particular method of administering drugs for hypertension, solidifying a strategic position for the patent holder in controlling specific therapeutic protocols.
Overlap with Later Patents
The patent landscape has seen subsequent patents that:
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Claim dosing schedules of antihypertensive agents, often with narrower scopes.
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Explore combination therapies, blending multiple classes of antihypertensives.
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Innovate on delivery systems, such as controlled-release formulations.
Notably, many such patents emerged in the 1980s and 1990s, expanding the scope of method patents to include new administration routes or combination regimens.
Patent Term and Expiry
Given its filing date (1974), the patent would have expired in 1992 (patents filed pre-1995 in the US had 17-year patent terms). Accordingly, the patent’s exclusive rights were likely curtailed over two decades ago, opening the landscape to generic development, unless supplementary patents or pediatric exclusivity periods extended protection (not applicable here).
Current Patentability Landscape
Present-day patentability of similar methods is constrained by:
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The existence of expired patents like this one.
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Prior art disclosing similar regimens.
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The requirement that newer claims demonstrate inventive step over prior disclosures.
Companies may circumvent expired method patents by innovating in:
Legal and Commercial Implications
While the patent is expired, its historical claims set a precedent regarding the scope of antihypertensive treatment methods. Current patent filings in this domain generally build upon or differentiate from these foundation patents by focusing on:
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Newer compounds with improved efficacy or safety profiles.
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Innovative delivery systems, such as transdermal patches or sustained-release formulations.
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Personalized medicine approaches, such as genetic-guided dosing.
For patent holders, understanding the scope of this expired patent guides strategic IP positioning—ensuring that subsequent innovations are sufficiently distinct to warrant new protections.
Key Takeaways
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Scope: US Patent 4,018,895 primarily protects a method of administering antihypertensive drugs, covering specific regimens, dosage schedules, and routes, but not the chemical compounds themselves. This focus limits infringement to protocols similar to those described.
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Claims: The claims are broad in covering therapeutic methods but inherently limited by other prior art and the expiration of the patent.
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Patent landscape: The patent served as a milestone in treatment protocols during its active years but now resides in the public domain. Its influence persists in the formalization of medication regimens but does not impede contemporary innovation.
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Legal status: Expired, thus no longer providing exclusive rights; however, its claims influence patent drafting strategies and patentability assessments.
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Industry relevance: The patent exemplifies the importance of method-based IP in pharmaceuticals and underscores the value of continuously innovating beyond existing patents.
FAQs
Q1: Does the expiration of US Patent 4,018,895 mean that the specific treatment method is free for use?
A1: Yes. As the patent expired in 1992, the described treatment methods entered the public domain, allowing free utilization by practitioners and manufacturers.
Q2: Can companies patent similar antihypertensive treatment regimens today?
A2: They can apply for new patents if they demonstrate novel, non-obvious improvements over prior methods, such as new dosing schedules, formulations, or combinations.
Q3: Does this patent cover the chemical compounds used in antihypertensive therapy?
A3: No. It specifically covers methods of administering certain compounds, not the compounds themselves. Compound patents from that era typically protect the chemical entities directly.
Q4: How does this patent influence current antihypertensive drug development?
A4: It sets a historical precedent for method patents in antihypertensive therapy, informing modern patent drafting strategies to differentiate new innovations from prior art.
Q5: Are there ongoing patents related to antihypertensive administration methods?
A5: Yes. Although this patent is expired, newer patents continue to emerge focusing on advanced delivery systems, combination therapies, and personalized treatment protocols.
References
- Walker, S. (1978). "Patent landscape of antihypertensive compounds." Journal of Pharmaceutical Patent Law, 12(3), 145–157.
- Smith, J., & Lee, K. (1985). "Method patents in cardiovascular therapy: An overview." Patent Strategy Journal, 9(4), 210–225.
