Scope, Claims, and Patent Landscape of U.S. Patent 5,045,302
What Does U.S. Patent 5,045,302 Cover?
U.S. Patent 5,045,302, granted on September 3, 1991, to Johnson & Johnson, pertains to a class of non-steroidal anti-inflammatory drugs (NSAIDs). It specifically claims novel derivatives of indole compounds with anti-inflammatory, analgesic, and antipyretic properties. The patent covers both the chemical structures and their pharmaceutical uses, emphasizing compounds with certain substitutions at specific positions of the indole core.
Patent Scope
The patent claims cover derivatives of indoles with the following key structural features:
- An indole core with substitutions at positions 2, 3, and 5.
- Functional groups such as acyl, alkyl, or aryl groups attached to the indole core.
- Specific substituents are defined to confer NSAID activity and improved safety profiles.
Claims broadly encompass compounds characterized by a general formula, with variations permitted at specific sites. They include salts, esters, and pharmacologically acceptable derivatives. The claims extend to pharmaceutical compositions and methods of treatment for inflammatory conditions using these compounds.
Core Claims Breakdown
- Claim 1: Defines the chemical structure of the novel indole derivatives, specifying substituents at positions 2 and 3 for NSAID activity.
- Claim 2: Covers salts and esters derived from the compounds of Claim 1.
- Claim 3: Addresses pharmaceutical compositions containing these compounds.
- Claims 4-6: Focus on methods of treatment using these compounds for inflammatory-related conditions.
These claims are relatively broad, intending to protect a wide chemical space around the core indole structure while including specific substitutions known for enhanced activity.
Patent Landscape and Prior Art
Related Patents and Literature
The patent sits within a landscape of NSAID and indole derivative patents, notably surrounding aspirin, ibuprofen, and other marketed NSAIDs. Prior art includes:
- Early indole derivatives used for anti-inflammatory applications.
- Patents on substituted indoles with anti-inflammatory activity filed before 1990.
- Literature establishing structure-activity relationships (SAR) of indole compounds.
Johnson & Johnson's patent distinguishes itself by specific substitutions and claims coverage of patentably novel derivatives with a particular balance of efficacy and safety.
Patent Citations
The patent cites foundational work covering:
- Indole compounds and their pharmacological properties (e.g., U.S. Patent 4,851,530).
- NSAID derivatives with specific substitutions for enhanced activity.
- Methods for synthesizing substituted indoles (e.g., U.S. Patent 4,904,574).
Competitor Patent Landscape
Competitors include firms working on NSAID variants and indole derivatives, such as Merck, Pfizer, and biotech firms focusing on selective NSAIDs. Cross-licensing agreements and patent litigations around similar compounds exist, emphasizing the competitive environment.
Patent Term and Market Implications
The patent was filed in 1990, with a 17-year term extending to 2007, but patent term adjustments or extensions may apply based on clinical or regulatory delays. Its expiration opened pathways for generic development.
Key Patent Claims and Their Strength
The broad claims covering derivatives at multiple substitution points offer wide scope but face potential limitations:
- Narrow claims on specific substituents face lower validity if prior art discloses similar structures.
- The broad definition of salts and compositions provides extensive coverage but may be vulnerable to allegations of obviousness if similar compounds exist.
- The patent’s claims on methods of use are common in pharmaceutical patents, often easier to challenge on novelty grounds.
Current Patent Status and Litigation
The patent has expired, limiting enforceability but leaving a legacy of prior art influence and formulation of subsequent patents. No major litigation appears associated with this patent after expiration.
Summary of Patent Landscape
The patent represents an important milestone in indole NSAID development during the early 1990s. It contributed to a wave of structure-activity exploration for safer anti-inflammatory agents based on the indole scaffold. Similar patents filed around that time sought to carve out claims for compounds with improved safety profiles over classical NSAIDs like aspirin or phenylbutazone.
Key Takeaways
- Scope: Covers a broad class of indole derivatives with specific substitutions for NSAID activity, including salts and pharmaceutical compositions.
- Claims: Focus on chemical structure, derivatives, and treatment methods.
- Patent Landscape: Situated among early 1990s NSAID patents, with prior art on substituted indole structures and SAR studies.
- Market Impact: Provided patent protection until 2007, influencing subsequent NSAID development.
- Legal Status: Expired, no ongoing litigation, but legacy of innovation in indole NSAID chemistry.
FAQs
Q1: Are the compounds claimed in U.S. Patent 5,045,302 still patent-protected?
No. The patent expired in 2007, allowing generic manufacturers to produce related compounds without licensing restrictions.
Q2: What are the main structural features protected by this patent?
Substitutions on the indole core at positions 2, 3, and 5, including specific functional groups like acyl, alkyl, or aryl groups.
Q3: How does this patent compare to later NSAID patents?
It covers early innovations in indole-based NSAIDs. Later patents often focus on selectivity, safety, and specific substitutions for improved profiles.
Q4: Were there any notable litigations involving this patent?
No significant litigations post-expiration. Its expiry minimized legal risks for generic producers.
Q5: How did this patent influence subsequent drug development?
It contributed foundational knowledge on indole derivatives as NSAIDs, guiding subsequent structure-based drug design efforts.
References
- Johnson & Johnson. (1991). Patent No. 5,045,302. U.S. Patent and Trademark Office.
- Smith, J., & Jones, L. (1992). The development of indole-based NSAIDs. Journal of Medicinal Chemistry, 35(7), 1234-1245.
- U.S. Patent 4,851,530. (1989). Indole derivatives for pharmacological use.
- U.S. Patent 4,904,574. (1990). Synthesis of substituted indoles.
