United States Patent 8,859,562: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 8,859,562, issued on October 14, 2014, is a significant patent in the field of cancer treatment, particularly involving the use of poly(ADP-ribose) polymerase (PARP) inhibitors. This patent is part of a broader portfolio related to the drug olaparib, marketed as Lynparza. Here, we will delve into the scope, claims, and the surrounding patent landscape of this patent.
Background
PARP inhibitors are a class of drugs that block the activity of PARP enzymes, which are involved in the repair of DNA damage. This mechanism is particularly effective in treating cancers with defects in homologous recombination repair, such as those associated with BRCA1 and BRCA2 mutations.
Patent Overview
Inventors and Assignees
The patent was invented by Thomas Helleday and assigned to The University of Sheffield and later to AstraZeneca, among other assignees[2][4].
Claims
The patent has a single claim that focuses on the use of PARP-1 inhibitors for the treatment of cancers with specific genetic defects. The claim specifically mentions the use of these inhibitors for the production of drugs targeting cancer cells defective in genes selected from XRCC2, XRCC3, and BRCA2[1][4].
Scope of Protection
Disease Mechanism
The patent's scope is defined by the disease mechanism it addresses. It targets cancers with defects in homologous recombination repair, which are more susceptible to PARP inhibition. This includes cancers with mutations in XRCC2, XRCC3, and BRCA2 genes[1][4].
Therapeutic Use
The patent protects the therapeutic use of PARP-1 inhibitors in the treatment of the aforementioned cancers. This includes the manufacture of medicaments that inhibit PARP activity to exploit the genetic vulnerabilities of these cancer cells[4].
Patent Landscape
Related Patents
The patent 8,859,562 is part of a larger patent portfolio related to olaparib. Other relevant patents include:
- US8071579 and US8143241: These patents claim the use of PARP inhibitors for treating BRCA1 and/or BRCA2 expression deficient cancer cells[1].
- US9861638: This patent covers the technical solution for different cancers treated with PARP inhibitors[1].
- US9987285: This patent relates to formulation research, including tablet and dry granular tablet formulations of olaparib[1].
Expiration Dates
The patent 8,859,562 is set to expire on August 4, 2031. This expiration date is crucial as it determines when generic versions of the drug can be approved and marketed[2][4].
Litigation and Challenges
The patent has been involved in litigation, particularly with generic manufacturers seeking to challenge its validity and enforceability. For example, Zydus Pharmaceuticals has submitted an Abbreviated New Drug Application (ANDA) to the FDA, alleging that the patent is invalid, unenforceable, or not infringed[5].
Impact on Generic Competition
ANDA Filings
Generic manufacturers like Zydus have filed ANDAs with the FDA, seeking approval to market generic versions of olaparib before the patent expires. These filings often include Paragraph IV certifications, which challenge the validity or enforceability of the patents-in-suit[5].
Patent Infringement Actions
The original patent holders, including AstraZeneca and KuDOS Pharmaceuticals Limited, have taken legal action against generic manufacturers to protect their patent rights. These actions aim to prevent the premature entry of generic competitors into the market[5].
Conclusion on Patent Strategy
The strategy behind the patent portfolio for olaparib involves multiple layers of protection, including composition of matter patents, method of use patents, and formulation patents. This layered approach helps to extend the patent protection period and delays the entry of generic competitors.
Key Takeaways
- Single Claim Focus: The patent has a single claim focused on the use of PARP-1 inhibitors for treating specific genetic defects in cancer cells.
- Disease Mechanism: The patent targets cancers with defects in homologous recombination repair.
- Expiration Date: The patent expires on August 4, 2031.
- Litigation: The patent is involved in ongoing litigation with generic manufacturers.
- Patent Portfolio: Part of a broader patent portfolio protecting various aspects of olaparib.
FAQs
Q: What is the main claim of United States Patent 8,859,562?
A: The main claim is the use of PARP-1 inhibitors for the production of drugs targeting cancer cells defective in genes selected from XRCC2, XRCC3, and BRCA2.
Q: Who are the inventors and assignees of this patent?
A: The inventors include Thomas Helleday, and the assignees include The University of Sheffield and AstraZeneca.
Q: What is the expiration date of this patent?
A: The patent is set to expire on August 4, 2031.
Q: How does this patent fit into the broader patent landscape for olaparib?
A: It is part of a layered patent strategy that includes composition of matter, method of use, and formulation patents to extend patent protection.
Q: Are there any ongoing legal challenges to this patent?
A: Yes, generic manufacturers like Zydus have filed ANDAs and challenged the validity and enforceability of the patent.
Sources
- Analysis of Strategy for Extending Patent Protection of Rucaparib - SCIRP
- Generic Lynparza Availability - Drugs.com
- The BioLoquitur Bulletin - Seyfarth Shaw LLP
- US8859562B2 - Use of RNAI inhibiting PARP activity - Google Patents
- Complaint against Zydus Pharmaceuticals - Insight.RPXcorp.com
