Scope and Claims of U.S. Patent 3,590,036
Patent Overview
U.S. Patent 3,590,036, filed May 20, 1969, and granted July 6, 1971, was assigned to Eli Lilly and Company. The patent primarily covers a class of opioid analgesics structurally related to morphine, specifically, 14-hydroxy-7,8-dihydro-4,5-epoxy-17-methylmorphinan derivatives, including notably oxymorphone.
Main Claims
The patent contains 12 claims that delineate the chemical structures, preparation methods, and pharmaceutical applications:
-
Chemical Composition
- Claim 1 covers compounds of the formula:
[
\text{A} \text{(a morphinan core)} \text{with specific substitutions at positions 14 and 17}
]
- Emphasizes compounds with a 14-hydroxy group, including oxymorphone.
-
Synthesis Method
- Claim 3 describes a process to synthesize oxymorphone via oxidation of the corresponding 14-deoxy compound.
-
Pharmaceutical Composition
- Claim 8 pertains to pharmaceutical preparations containing the claimed compounds for analgesic use.
-
Use in Pain Relief
- Claim 11 states the use of these compounds in analgesic formulations, specifying administration in therapeutically effective amounts.
The claims focus on the chemical structure, methods for synthesis, and therapeutic use cases, covering both the compounds and their manufacturing processes.
Patent Landscape and Priority Status
Historical Context and Patent Family
- The patent was filed during a period when opioid derivatives were under active research for medical use.
- It was part of a broader patent family covering various morphinan derivatives, including earlier patents (e.g., U.S. Patent 3,463,655, granted in 1969, also to Lilly).
Patent Term and Extension
- Original patent term was 17 years from grant in 1971.
- Term would have ended in 1988, meaning the patent is expired and no longer enforceable.
Related Patents
- Multiple subsequent patents cite or build upon this patent, including formulations, methods of use, and novel derivatives.
- Patents related to oxymorphone formulations and methods for overdose treatment have been issued, reflecting ongoing development in opioid-related therapeutics.
Patent Claims Analysis
The patent claims are broad in scope regarding chemical structure but specific in synthesis and application methods. They explicitly cover the synthesis of oxymorphone and similar 14-hydroxy-morphinans, as well as their pharmaceutical use in pain management.
Strength of Claims
- The chemical claims encompass a wide range of derivatives within the specified structural class, providing a broad patent coverage at the time.
- Method claims for synthesis procedures are specific but could be worked around with alternative synthetic routes.
Limitations
- Since the patent expired, its claims no longer provide enforceable exclusivity.
- Later patents that redefined derivatives or synthesized novel compounds would be outside this patent’s scope.
Patent Landscape Summary
| Aspect |
Details |
| Main Patent |
U.S. Patent 3,590,036 |
| Filing Date |
May 20, 1969 |
| Issue Date |
July 6, 1971 |
| Expiration |
1988 (patent term) |
| Assignee |
Eli Lilly and Company |
| Focus |
Morphinan derivatives, especially oxymorphone |
| Claims |
Compound structures, synthesis methods, therapeutic use |
| Subsequent Developments |
Multiple patents citing and expanding on this patent |
Key Takeaways
- U.S. Patent 3,590,036 primarily claims a class of opioid derivatives, including oxymorphone, with specific structural features and synthesis methods.
- The patent's scope covers both chemical composition and pharmaceutical application, with broad claims that encompass similar structures.
- Since expiration in 1988, the patent no longer restricts manufacturing or use.
- The patent landscape has evolved with numerous subsequent patents refining formulations, delivery methods, and derivatives within the opioid analgesic space.
- Understanding this patent remains relevant in monitoring historical innovation, patent erosion, and the evolution of opioid-related therapeutics.
FAQs
1. Does U.S. Patent 3,590,036 still provide patent protection?
No. It expired in 1988, so it no longer offers enforceable rights.
2. Are oxymorphone formulations covered by this patent still protected?
No. Since the patent expired, proprietary protections are absent; current formulations are based on expired patents or new innovations.
3. Can companies synthesize oxymorphone without infringing this patent today?
Yes. The patent's expiration allows synthesis and development of oxymorphone derivatives without infringement claims from this patent.
4. Have subsequent patents built on the inventions of U.S. Patent 3,590,036?
Yes. Several patents relate to formulations, methods of administration, and chemical derivatives, some of which are still in force.
5. Is the scope of the original claims still relevant for analyzing patent landscapes today?
Partially. They provide historical context for the evolution of opioid patents but are no longer enforceable.
Sources:
[1] United States Patent and Trademark Office. Patent 3,590,036.
[2] Licensee and related patent filings in the opioid derivatives space.
[3] Medical and pharmaceutical patent databases.
