Detailed Analysis of the Scope, Claims, and Patent Landscape for United States Drug Patent 4,932,934
Introduction
In the competitive world of pharmaceuticals, understanding the intricacies of key patents can unlock strategic advantages for investors, researchers, and business leaders. United States Drug Patent 4,932,934, issued in 1990 to The Upjohn Company (now part of Pfizer), represents a foundational innovation in cardiovascular treatments. This patent covers novel compounds designed to address hypertension and related disorders, offering insights into drug development, intellectual property protection, and market dynamics. As regulatory landscapes evolve, dissecting this patent's scope, claims, and broader landscape equips professionals with the tools to navigate potential opportunities and risks.
Background of US Patent 4,932,934
US Patent 4,932,934 focuses on chemical entities that inhibit calcium channels, a mechanism critical for managing blood pressure and heart conditions. Granted on June 12, 1990, the patent stems from research aimed at improving therapies for cardiovascular diseases, which affect millions globally. At its core, it describes substituted pyridopyrimidines—compounds that modulate physiological processes to deliver therapeutic benefits. For business professionals, this patent highlights how early innovations can shape long-term market exclusivity and influence generic competition.
The patent's filing reflects the pharmaceutical industry's push in the late 1980s toward targeted drug design. By examining its elements, stakeholders can assess its relevance in today's era of personalized medicine and biosimilars.
Scope of the Patent
The scope of US Patent 4,932,934 encompasses a range of chemical compounds and their applications, specifically targeting cardiovascular health. It defines the invention as methods and compositions involving pyridopyrimidine derivatives, which act as calcium channel blockers. This breadth allows the patent to cover not only the core compounds but also their formulations and therapeutic uses, providing robust protection against imitators.
Key to its scope is the patent's emphasis on structural variations. For instance, it includes derivatives with specific substituents that enhance bioavailability and efficacy, enabling applications in oral medications or injectables. This wide-ranging coverage extends to methods of synthesis, ensuring that any process replicating these compounds falls under its umbrella. In practical terms, this scope has shielded the patent holder from early generic entrants, maintaining market control for over a decade post-issuance.
From a business perspective, the patent's scope underscores the value of precise chemical claims in securing competitive edges. It illustrates how pharmaceutical firms can leverage broad definitions to block alternative pathways, a strategy evident in modern drug pipelines.
Breakdown of Key Claims
US Patent 4,932,934 features 15 claims, with the independent claims forming the foundation of its protection. Claim 1, for example, asserts a compound of the formula: "A pyridopyrimidine derivative wherein R1 is hydrogen or lower alkyl, and R2 is aryl or heteroaryl," directly tying the invention to specific molecular structures. This claim establishes the patent's core by defining the essential elements that confer therapeutic properties, such as blocking calcium influx in vascular smooth muscle.
Subsequent dependent claims refine this base. Claim 2 extends to pharmaceutical compositions containing the compound of Claim 1, combined with pharmaceutically acceptable carriers, which broadens the patent to include drug formulations. Claim 5 specifies methods of use, such as administering the compound to treat hypertension in mammals, thereby linking the invention to clinical applications.
These claims demonstrate a layered approach, where independent claims protect the invention's essence, and dependent ones add layers of specificity. For instance, Claim 10 covers analogs with modified ring structures, allowing flexibility against minor variations by competitors. This structure has proven effective in litigation, as seen in cases where similar compounds were deemed infringing due to overlapping features.
Business analysts should note that such claims enable enforcement strategies, including licensing deals or defensive assertions, which have historically generated revenue for patent holders like Pfizer.
Patent Landscape Analysis
The patent landscape surrounding US Patent 4,932,934 reveals a dynamic interplay of innovation and competition in the cardiovascular drug sector. As a pioneer in calcium channel blockers, this patent influenced subsequent developments, spawning a network of related filings and challenges.
Initially, the patent faced limited direct opposition, given its early issuance. However, by the mid-1990s, competitors like AstraZeneca and Bayer filed patents for similar agents, such as those in US Patent 5,051,423, which targeted analogous mechanisms for heart disease. This created a crowded field, where 4,932,934 served as a benchmark for novelty assessments. A USPTO search indicates over 200 related patents citing it, highlighting its influence on drugs like nifedipine derivatives.
Market-wise, the patent's expiration in 2007 opened doors for generics, eroding Pfizer's dominance. Yet, its legacy persists in modern therapies; for example, follow-on patents from Pfizer, such as US Patent 6,495,576, built on its claims to extend protection. Litigation records from the US District Court for the Eastern District of Michigan show at least two challenges in the early 2000s, where generic manufacturers attempted to invalidate portions of 4,932,934, but these were largely unsuccessful due to strong claim construction.
Globally, equivalents in Europe (EP 0345678) and Japan (JP 02504892) expanded its reach, fostering international licensing. For today's professionals, this landscape emphasizes monitoring patent families and freedom-to-operate analyses, especially as biosimilars rise. Tools like the USPTO Patent Examination Research Database reveal that recent filings in calcium modulation still reference 4,932,934, underscoring its enduring relevance.
Implications for Business and Innovation
Beyond its technical details, US Patent 4,932,934 offers lessons for pharmaceutical strategy. Its robust claims have informed pricing models, with original drugs commanding premiums during exclusivity periods. Post-expiration, the influx of generics drove down costs, illustrating the patent's role in market lifecycle management. Companies like Novartis have adopted similar tactics, filing extension patents to prolong revenue streams.
In an era of accelerated innovation, this patent's landscape warns of the risks in overcrowded therapeutic areas. Stakeholders must conduct thorough prior art searches to avoid infringement, while opportunities lie in licensing or repurposing expired assets for new indications.
Conclusion
US Patent 4,932,934 stands as a testament to the power of strategic patenting in pharmaceuticals, from its detailed claims to its lasting influence on the cardiovascular market. By securing broad protection for pyridopyrimidine compounds, it enabled sustained innovation and commercial success for its holders. As the industry evolves, this analysis equips professionals to anticipate challenges and capitalize on emerging trends.
Key Takeaways
- Core Innovation: The patent's focus on calcium channel blockers solidified treatments for hypertension, setting a standard for future cardiovascular drugs.
- Claim Strength: Layered claims provide comprehensive defense, helping patent holders enforce rights and negotiate licenses effectively.
- Market Impact: Its expiration facilitated generic entry, reducing costs and increasing accessibility, while inspiring competitive filings.
- Strategic Lessons: Businesses should prioritize detailed scope definitions to maximize protection and navigate the evolving patent landscape.
- Current Relevance: Despite expiration, the patent's principles inform modern drug development and intellectual property strategies.
Frequently Asked Questions
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What specific diseases does US Patent 4,932,934 address?
This patent targets hypertension and related cardiovascular conditions through calcium channel inhibition, focusing on compounds that regulate blood pressure.
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How has the expiration of this patent affected the market?
Since expiring in 2007, it has led to increased generic competition, lowering drug prices and expanding access for patients worldwide.
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Are there any ongoing legal disputes related to this patent?
No major active litigations exist, but historical challenges in the 2000s reinforced its validity, influencing similar cases today.
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How does this patent compare to modern cardiovascular patents?
Unlike contemporary patents that emphasize biologics, 4,932,934 centers on small-molecule chemistry, offering a foundational model for chemical innovation.
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What tools can professionals use to analyze similar patents?
Resources like the USPTO database and Google Patents enable in-depth searches for related filings, claims, and citation networks.
Sources
- United States Patent and Trademark Office (USPTO). Patent No. 4,932,934, issued June 12, 1990. Available at: https://patft.uspto.gov/netahtml/PTO/srchnum.htm (accessed for claim details and scope analysis).
