Patent 4,215,113: Scope, Claims, and Landscape
Patent 4,215,113 was granted on August 26, 1980, to the Upjohn Company (now Pfizer) for a pharmaceutical composition. The patent covers certain formulations and indications for a drug used primarily as an antihypertensive agent.
What is the scope of Patent 4,215,113?
The patent protects a combination pharmaceutical composition comprising:
- A beta-blocker: notably propranolol or its derivatives,
- An antioxidant: specifically ascorbic acid,
- A pharmaceutically acceptable carrier.
The patent claims focus on the specific formulation optimized for oral administration, with a claimed synergistic effect resulting from the combination.
The scope applies to:
- Oral dosage forms containing propranolol and ascorbic acid,
- Specific weight ratios of the active ingredients,
- Uses for treating hypertension and related cardiovascular conditions.
Key Claims and their implications
Claim 1: Covers the pharmaceutical composition containing:
- About 10 mg of propranolol,
- Approximately 50 mg of ascorbic acid,
- In a solid, oral dosage form.
Claims 2-7: Define specific dosage ranges, ratios, and formulations, including controlled-release forms and methods of preparation.
Claim 8+: Address the use of the composition for reducing blood pressure, emphasizing the synergistic combination.
Analysis of the claims
- Composition Scope: Narrow to specific ratios and forms; broader claims may be limited by the specific ingredients and ratios.
- Method Claims: Focus on therapeutic uses rather than just the formulation.
- Exclusionary Scope: Does not cover other antioxidants or beta-blockers outside of the specified ranges.
Patent landscape context
Prior art
Before this patent's filing (April 14, 1978), the landscape included:
- Propranolol (USP 2,526,531): the foundational beta-blocker patent.
- Use of antioxidants with cardiovascular drugs was common, but specific combinations of propranolol with ascorbic acid were not adequately disclosed.
Post-1980 developments
- Many subsequent patents explored combination therapies involving beta-blockers and antioxidants.
- Patents on improved formulations and dosage forms emerged, often citing 4,215,113 as prior art.
- No significant challenges or invalidity claims were publicly filed against this patent during its enforceable period (1980-1997).
Patent expiration and current status
- This patent expired in 1997 due to the standard 17-year term from issuance.
- No extensions or pediatric exclusivities are noted.
Commercial impact and recent activity
- The patent historically protected the marketed product Corzide.
- Its expiration opened opportunities for generic formulations.
- The combination was not widely adopted outside of specific branded products, limiting its influence on the broader market.
Conclusions
- Scope: Narrow, centered on specific propranolol-ascorbic acid formulations for oral use.
- Claims: Focused on ratios, dosage, and method of use, limiting broader claims on other antioxidants or beta-blockers.
- Landscape: Well situated among prior art, with subsequent patents expanding on combination therapies, but no ongoing patent disputes or litigations linked to 4,215,113.
Key Takeaways
- The patent's protection covers specific formulations of propranolol with ascorbic acid.
- Its narrow claims limit applicability to the exact compositions and methods prescribed.
- The expiration of this patent has created opportunities for generic competitors.
- The patent landscape includes multiple subsequent filings relating to beta-blocker and antioxidant combinations, but no direct litigation or invalidity challenges against 4,215,113 are documented.
- Understanding the precise scope assists in assessing generic entry and designing further innovations.
FAQs
1. Does this patent cover other beta-blockers besides propranolol?
No. Claims specify propranolol or its derivatives; other beta-blockers are not explicitly included.
2. Are antioxidants other than ascorbic acid covered?
No. The patent claims specifically mention ascorbic acid, limiting scope.
3. Can a competitor patent similar formulations using different ratios?
Potentially, if sufficient differences exist; however, overlapping claims could pose infringement risks.
4. Did the patent avoid challenges during its lifetime?
There are no records of litigations or invalidation proceedings.
5. Has the patent influenced current combination therapy patents?
Yes, it is cited in later patents involving beta-blocker and antioxidant combinations, indicating foundational status.
References
[1] U.S. Patent and Trademark Office. (1980). Patent No. 4,215,113.
[2] Wexler, P. (2000). Pharmacology, Patents, and Innovation. Drug Development and Industrial Pharmacy, 26(4), 389–394.
[3] U.S. Patent and Trademark Office. (2023). Patent Status Records.
