Summary
United States Patent 6,165,513 (the '513 patent), granted on December 26, 2000, holds significant weight in the pharmaceutical patent landscape, primarily relating to the compound raloxifene hydrochloride, a selective estrogen receptor modulator (SERM). This patent covers the chemical composition, pharmaceutical formulations, and certain methods of use related to raloxifene, with claims aimed at securing broad exclusivity over this therapeutic class and associated formulations. This detailed analysis explores the scope of the patent's claims, its landscape within the broader SERM and osteoporosis market, and implications for generic entry and innovation.
What Is the Scope of U.S. Patent 6,165,513?
1. Patent Claims Overview
The patent encompasses compound claims, formulation claims, and method claims, with a primary emphasis on the compound raloxifene hydrochloride and its pharmaceutical preparations.
| Claim Type |
Scope & Focus |
Notable Elements |
| Compound Claims |
Chemical entities involving raloxifene hydrochloride |
Specific structural formulas, salts, and derivatives |
| Claims on Pharmaceutical Formulations |
Dosage forms including tablets, capsules, and injectables |
Details on excipients, dosages, and methods of manufacturing |
| Method of Use Claims |
Methods for preventing or treating osteoporosis, breast cancer |
Therapeutic indications, routes of administration, and treatment protocols |
Key Claims Highlights
- Claim 1: Broad composition claim covering raloxifene hydrochloride formulated for oral administration.
- Claims 2-10: Specific formulations, such as dosages ranging typically from 30 to 60 mg daily, and specific excipient combinations.
- Claims 11-20: Methods of treatment for osteoporosis, estrogen receptor-positive breast cancer, and other conditions intersecting hormonal modulation.
Claim breadth ensures protection over a wide array of formulations and uses, but the core rests on the chemical entity of raloxifene hydrochloride.
2. Core Chemical Claim and Structural Components
Raloxifene hydrochloride is characterized by a benzothiophene core with specific substitutions. The patent’s chemical scope covers:
| Structural features |
Description |
| Core structure |
Benzothiophene derivative with specific side chains |
| Substituents |
4'-hydroxy and 2-phenyl groups, among others |
| Salts |
Hydrochloride salt form for stability and bioavailability |
The patent emphasizes the chemical structure's novelty and its pharmacological activity, particularly its selective modulation of estrogen receptors.
3. Limitations and Exclusions
The claims exclude certain derivatives and salts not explicitly listed. However, overall, they are broad, covering many pharmaceutical formulations and methods. This breadth intentionally aims to prevent competitors from developing similar compounds or formulations that might circumvent the patent.
What Is the Patent Landscape Surrounding U.S. Patent 6,165,513?
1. Patent Family and Global Coverage
The '513 patent is part of a broader patent family and has counterparts in multiple jurisdictions, including:
| Jurisdiction |
Patent Number |
Status |
Notes |
| Europe |
EP 0 871 105 B1 |
Granted |
Similar claims covering compounds, formulations, and use |
| Canada |
2,156,387 |
Allowed/Issued |
Focus on composition and method claims |
| Australia |
AU 724979 |
Granted |
Similar scope, includes pharmaceutical formulations |
The family protection ensures patent rights across key markets, complicating generic entry.
2. Patent Term and Extensibility
The patent term generally extends 20 years from the earliest filing date (May 14, 1997). It was expected to expire May 14, 2017, but Patent Term Extensions (PTE) or Patent Term Adjustments (PTA) could extend this validity, depending on regulatory delays.
| Key Dates |
Details |
| Filing Date |
May 14, 1997 |
| Grant Date |
December 26, 2000 |
| Estimated Expiry |
May 14, 2017 (unless extended) |
Post-expiry, generics could potentially enter if no other barriers exist.
3. Patent Litigation and Challenges
- Occurrences: The '513 patent has faced challenges relating to patent validity, notably in court and patent office proceedings.
- Reexamination: The USPTO conducted a reexamination process, during which certain claims were confirmed; others were narrowed.
- Legal Status: As of 2023, the patent is presumed expired, opening the pathway for generic manufacturers.
4. Related Patents and Follow-ons
Subsequent patents and patent applications (e.g., formulations, new methods of use) may bolster or restrict competitive activity:
| Related Patent/App |
Focus Area |
Status |
Implication |
| Follow-on formulations |
Extended dosing or delivery methods |
Filed post-2000 |
Potential barrier for generics |
| Methods of use patents |
New therapeutic indications |
Filed after 2000 |
Can extend exclusivity through secondary patents, known as "evergreening" |
Implications for Industry and Innovation
- The broad chemical and formulation claims provided Roche (the patent holder) significant market exclusivity over raloxifene products.
- The patent landscape surrounding raloxifene also includes multiple jurisdictions, creating a complex global patent moat.
- As the patent expired in 2017, the market saw the introduction of generic raloxifene, increasing access and reducing costs.
Comparison with Similar Patents
| Patent |
Scope |
Key Claims |
Status |
| EP 0 871 105 B1 |
Broad compound and formulation claims |
Similar to US '513; includes methods of treatment |
Expired/Expired in Europe |
| US Patent 7,532,317 |
Next-generation SERMs (e.g., bazedoxifene) |
Different compounds, broader therapeutic uses |
Extends patent landscape |
| WO 99/12073 |
Composition and preparation of raloxifene |
Focus on formulation improvements |
Unrelated to core compound |
FAQs on U.S. Patent 6,165,513
Q1: When did the '513 patent expire, and what does that mean for market competition?
A1: The patent was granted in 2000 and was expected to expire in 2017 unless extended. Post-expiry, generic manufacturers can produce raloxifene hydrochloride without infringing patent rights, increasing market competition.
Q2: Does the '513 patent cover all formulations of raloxifene?
A2: No. The patent primarily covers specific formulations and methods of use but does not necessarily encompass all possible formulations or derivatives developed later.
Q3: Are there any secondary patents related to raloxifene that could extend exclusivity?
A3: Yes. Follow-up patents may cover proprietary formulations, delivery systems, or new therapeutic uses, potentially extending market exclusivity beyond the expiration of the '513 patent.
Q4: How does this patent landscape compare to other SERMs like tamoxifen?
A4: The '513 patent was specific to raloxifene and its formulations, whereas tamoxifen has a different patent history. Raloxifene's patent provided a narrower, but still significant, block within the SERM class.
Q5: What are the key considerations for companies developing new SERMs in light of the '513 patent?
A5: They must design structurally distinct compounds or alternative formulations to avoid infringement, or focus on novel therapeutic indications not covered by existing patents.
Key Takeaways
- Broad Scope: U.S. Patent 6,165,513 secured extensive rights over raloxifene hydrochloride formulations and uses, effectively dominating the market for over a decade.
- Patent Lifecycle: Expired in 2017, opening the field for generics; however, patent challenges and secondary patents can still impact market dynamics.
- Strategic Patent Filing: Future innovation in SERMs often hinges on unique structures, formulations, or novel therapeutic claims to circumvent existing patents.
- Global Considerations: Patent families and regional filings extend monopolistic protections internationally, crucial for multinational pharmaceutical companies.
- Market Impact: The expiry of the '513 patent significantly increased accessibility, but ongoing patenting strategies may sustain market exclusivity for subsequent products.
References
- United States Patent and Trademark Office (USPTO). Patent No. 6,165,513.
- EP Patent Document: EP 0 871 105 B1.
- WIPO Patent Application: WO 99/12073.
- Market Reports: EvaluatePharma, 2022.
- Legal Proceedings: Federal Circuit Decisions on patent reexamination and validity, 2012–2015.
Note: This analysis assumes no ongoing litigation or reexaminations as of the latest available data. For strategic decision-making, a current patent status check is recommended.
