United States Patent 9,808,465: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
The United States Patent 9,808,465, hereafter referred to as the '465 patent, is one of the key patents held by Heron Therapeutics, Inc., and is central to several ongoing patent infringement cases. This patent pertains to stable, injectable formulations of aprepitant, a compound used to treat chemotherapy-induced nausea and vomiting (CINV).
Background on Aprepitant
Aprepitant is a substance P/neurokinin 1 receptor antagonist that plays a crucial role in managing nausea and vomiting associated with chemotherapy and surgery[4].
Scope of the Patent
The '465 patent is part of a series of patents that Heron Therapeutics has asserted against various generic drug manufacturers. The patent covers specific formulations and methods related to aprepitant.
Claim 1 of the '465 Patent
Claim 1 of the '465 patent is particularly significant as it defines the core composition and characteristics of the pharmaceutical formulation. It includes:
- A physically stable pharmaceutical composition comprising:
- 0.4 wt/wt % to 1.0 wt/wt % aprepitant
- 13 wt/wt % to 15 wt/wt % egg yolk lecithin
- 9 wt/wt % to 10 wt/wt % soybean oil
- A pH modifier, specifically sodium oleate
- The pH of the composition ranging from 7.5 to 9.0[1].
Physical Stability Definition
The definition of "physically stable" is a critical aspect of the patent. According to the specification, for an emulsion to be considered physically stable, it must remain stable for at least one week, whether stored at room temperature or in refrigerated conditions at 5°C. This stability is determined based on tests conducted on several emulsions described in the patent[1].
Claim Construction Disputes
In the context of patent litigation, the construction of claims is often a point of contention. For the '465 patent, disputes have arisen regarding the interpretation of "physically stable" and the storage conditions required. Heron Therapeutics argues that the emulsion must remain stable for at least one week under specified conditions, while defendants like Fresenius Kabi USA, LLC, have questioned the clarity and specificity of these requirements[1].
Patent Landscape
The patent landscape surrounding aprepitant and its formulations is complex and highly contested.
Patent Family and Assignees
The patents related to aprepitant, including the '465 patent, are part of a larger family of patents held by Heron Therapeutics. These patents cover various aspects of aprepitant formulations, methods of preparation, and uses. Heron Therapeutics is the primary assignee, and these patents are crucial for protecting their branded drug, CINVANTI[2][5].
Innovation Tracks and Protection
Similar to the patent landscape report on Ritonavir, the protection around aprepitant involves multiple innovation tracks, including liquid dosage formulations, methods of preparation, and specific composition characteristics. These tracks illustrate the ongoing efforts to narrow and extend patent protection, a phenomenon sometimes referred to as "evergreening"[3].
Litigation and Infringement Claims
Heron Therapeutics has initiated several lawsuits against generic drug manufacturers, including Fresenius Kabi USA, LLC, and Mylan, alleging infringement of the '465 patent among others. These lawsuits seek declaratory judgments and permanent injunctions to prevent the manufacture and sale of generic versions of CINVANTI[2][5].
Industry Impact
The '465 patent and related patents have significant implications for the pharmaceutical industry, particularly in the area of CINV treatment. The stability and efficacy of aprepitant formulations are critical for patient care, and the patent protection ensures that Heron Therapeutics maintains a competitive edge in the market.
Expert Insights
Industry experts emphasize the importance of robust patent protection in the pharmaceutical sector. As noted by legal experts, "The ability to protect innovative formulations like those covered by the '465 patent is essential for encouraging continued research and development in the field of pharmaceuticals"[2].
Statistical Analysis and Patent Expiration
The '465 patent, along with other related patents, is set to expire in 2035. This timeline is crucial for both Heron Therapeutics and potential generic manufacturers, as it defines the window during which Heron can exclusively market CINVANTI[4].
Conclusion and Future Outlook
The '465 patent is a cornerstone in Heron Therapeutics' intellectual property portfolio, safeguarding their innovative aprepitant formulations. As the patent landscape continues to evolve, it is likely that Heron will continue to defend its patents vigorously against generic challenges.
Key Takeaways
- The '465 patent covers stable, injectable formulations of aprepitant.
- The definition of "physically stable" is critical and requires stability for at least one week under specified conditions.
- Heron Therapeutics is actively litigating to protect this patent against generic manufacturers.
- The patent is set to expire in 2035.
- The patent landscape around aprepitant is complex and involves multiple innovation tracks.
Frequently Asked Questions (FAQs)
1. What is the primary compound protected by the '465 patent?
The primary compound protected by the '465 patent is aprepitant, a substance P/neurokinin 1 receptor antagonist used to treat nausea and vomiting caused by chemotherapy and surgery.
2. What are the key components of the pharmaceutical composition described in Claim 1 of the '465 patent?
The key components include 0.4 wt/wt % to 1.0 wt/wt % aprepitant, 13 wt/wt % to 15 wt/wt % egg yolk lecithin, 9 wt/wt % to 10 wt/wt % soybean oil, and a pH modifier, specifically sodium oleate.
3. What is meant by "physically stable" in the context of the '465 patent?
For an emulsion to be considered physically stable, it must remain stable for at least one week, whether stored at room temperature or in refrigerated conditions at 5°C.
4. Who is the primary assignee of the '465 patent?
The primary assignee of the '465 patent is Heron Therapeutics, Inc.
5. When is the '465 patent set to expire?
The '465 patent is set to expire in 2035.
Cited Sources:
- IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF DELAWARE HERON THERAPEUTICS, INC., Plaintiff, v. FRESENIUS KABI USA, LLC, Defendant.
- Heron Therapeutics, Inc. v. Slayback Pharma LLC - Casetext
- Patent Landscape Report on Ritonavir - WIPO
- Aprepitant: Uses, Interactions, Mechanism of Action | DrugBank Online
- in the united states district court - RPX Insight
