United States Patent 6,107,302: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 6,107,302, titled "Guanine derivative," is a significant patent in the field of antiviral medications, particularly focusing on Valacyclovir hydrochloride. This patent, assigned to GlaxoSmithKline (GSK), revolves around the production and characteristics of an anhydrous crystalline form of Valacyclovir hydrochloride, a prodrug of the widely used antiviral agent Acyclovir.
Background of Valacyclovir and Acyclovir
Valacyclovir is an L-Valyl ester prodrug of Acyclovir, which is an acyclic analog of a natural nucleoside. Acyclovir, known for its potent antiviral activity, is widely used in the treatment and prophylaxis of viral infections, especially those caused by the herpes group of viruses[1][4].
Scope of the Patent
The patent 6,107,302 primarily deals with the discovery and production of a new anhydrous crystalline form of Valacyclovir hydrochloride. This form is significant because it enhances the performance characteristics of the pharmaceutical product, such as bioavailability and stability.
Anhydrous Crystalline Form
The patent describes a process for producing Valacyclovir hydrochloride in an anhydrous crystalline form. This involves treating Valacyclovir hydrochloride with a solubilizing solvent to convert it into the desired crystalline form, which is then isolated. The anhydrous form is crucial as it improves the drug's stability and potentially its bioavailability compared to other forms[1][4].
Claims of the Patent
The patent includes several key claims:
Process of Production
- The patent claims a process for producing Valacyclovir hydrochloride in an anhydrous crystalline form. This process involves specific steps, including the use of a solubilizing solvent to achieve the desired crystalline structure[1][4].
Crystalline Form Characteristics
- The patent specifies the characteristics of the anhydrous crystalline form, including its d-spacing pattern, which is a unique identifier for this particular form of the compound[1][4].
Pharmaceutical Applications
- The claims extend to the use of this anhydrous crystalline form in pharmaceutical preparations, highlighting its potential for improved drug performance and patient outcomes[1][4].
Patent Landscape
Litigation and Settlements
The patent 6,107,302 has been involved in significant litigation, particularly between GSK and generic drug manufacturers like Ranbaxy Laboratories. Ranbaxy obtained a license to GSK's U.S. Patent Nos. 5,879,706 and 6,107,302 as part of a settlement agreement, allowing Ranbaxy to manufacture and market generic versions of Valacyclovir hydrochloride under certain conditions[2][5].
Related Patents
The patent is linked to other patents related to Valacyclovir and Acyclovir, such as U.S. Patent No. 4,957,924, which covers the use of Valacyclovir hydrochloride in treating herpes virus infections. These patents collectively form a robust intellectual property portfolio around these antiviral compounds[1][4][5].
Impact on Pharmaceutical Industry
Improved Drug Performance
The discovery of the anhydrous crystalline form of Valacyclovir hydrochloride has significant implications for the pharmaceutical industry. It provides formulation scientists with a new material that can be designed to have a targeted release profile or other desired characteristics, potentially enhancing the efficacy and patient compliance of the drug[4].
Competitive Landscape
The patent and its associated litigation have shaped the competitive landscape in the antiviral drug market. The settlement agreements and licensing arrangements have allowed generic manufacturers to enter the market, increasing competition and potentially reducing costs for consumers[2][5].
Key Takeaways
- Anhydrous Crystalline Form: The patent 6,107,302 introduces a new anhydrous crystalline form of Valacyclovir hydrochloride, enhancing the drug's stability and bioavailability.
- Production Process: The patent details a specific process for producing this crystalline form using a solubilizing solvent.
- Pharmaceutical Applications: The anhydrous form has significant implications for pharmaceutical preparations, offering improved performance characteristics.
- Litigation and Settlements: The patent has been involved in litigation and settlement agreements, influencing the market entry of generic versions.
- Impact on Industry: The discovery has expanded the repertoire of materials available for drug formulation and has shaped the competitive landscape in the antiviral drug market.
FAQs
What is the main focus of United States Patent 6,107,302?
The main focus of this patent is the production and characteristics of an anhydrous crystalline form of Valacyclovir hydrochloride.
How does the anhydrous crystalline form of Valacyclovir hydrochloride improve the drug?
The anhydrous form improves the drug's stability and potentially its bioavailability, which can enhance its efficacy and patient compliance.
What is the significance of the process described in the patent?
The process described involves using a solubilizing solvent to convert Valacyclovir hydrochloride into the desired anhydrous crystalline form, which is then isolated.
How has the patent affected the market for antiviral drugs?
The patent and associated litigation have allowed generic manufacturers to enter the market under licensing agreements, increasing competition and potentially reducing costs for consumers.
What other patents are related to this one?
The patent is related to other patents such as U.S. Patent No. 4,957,924, which covers the use of Valacyclovir hydrochloride in treating herpes virus infections.
Sources
- US6107302A - Guanine derivative - Google Patents
- Ranbaxy Laboratories and GlaxoSmithKline Enter Into an Agreement to Settle Valacyclovir U.S. Patent Litigation - Biospace
- Patent Claims and Patent Scope - SSRN
- United States Patent - googleapis.com
- Ranbaxy, GSK sign pact to settle valacyclovir US patent litigation - Pharmabiz
