Details for Patent: 5,714,504

Summary for Patent: 5,714,504

Title:	Compositions
Abstract:	The novel optically pure compounds Na.sup.+, Mg.sup.2+, Li.sup.+, K.sup.+, Ca.sup.2+ and N.sup.+ (R).sub.4 salts of (+)-5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]sulfinyl]-1H- benzimidazole or (-)-5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]sulfinyl]-1H- benzimidazole, in particular sodium and magnesium salt form thereof, where R is an alkyl with 1-4 carbon atoms, processes for the preparation thereof and pharmaceutical preparations containing the compounds as active ingredients, as well as the use of the compounds in pharmaceutical preparations and intermediates obtained by preparing the compounds.
Inventor(s):	Lindberg; Per Lennart (Molndal, SE), Von Unge; Sverker (Fjar.ang.s, SE)
Assignee:	Astra Aktiebolag (Sodertalje, SE)
Application Number:	08/376,512
Patent Claim Types: see list of patent claims	Composition; Formulation; Compound; Dosage form; Use;

United States Patent 5,714,504: A Detailed Analysis of Scope, Claims, and Patent Landscape

Introduction

United States Patent 5,714,504, owned by AstraZeneca, is a pivotal patent in the pharmaceutical industry, particularly in the context of esomeprazole, the active ingredient in the drug Nexium. This patent has been at the center of several high-profile litigation cases and has significant implications for patent scope, claim construction, and the broader patent landscape.

Background of the Patent

The patent, filed in 1995 and granted in 1998, covers various salts of esomeprazole, a proton pump inhibitor used to treat conditions like gastroesophageal reflux disease (GERD). The patent is part of a larger family of patents related to esomeprazole and its salts, including U.S. Patent Numbers 5,877,192 and 6,369,085[2][4].

Claims of the Patent

The patent includes several claims that define the scope of the invention. Key claims include:

• Claim 1: This claim specifies the sodium salt of esomeprazole, which is one of the primary embodiments of the invention.
• Claims 2, 4, 6, and 7: These claims cover other alkaline salts of esomeprazole, including magnesium, lithium, potassium, calcium, and ammonium salts[5].

Claim Construction and Scope

The construction of claims in this patent has been a subject of intense litigation. Here are some critical aspects:

• Term "Alkaline Salt": The term "alkaline salt" has been narrowly construed to include only the six specific salts mentioned in the specification: sodium, magnesium, lithium, potassium, calcium, and ammonium salts. The Federal Circuit affirmed this construction, ruling that the specification clearly disclaims other members of the class[4].
• Disclaimer in Specification: The use of the term "the present invention" in the specification has been interpreted to limit the claim scope to the specific embodiments described. This highlights the importance of careful drafting in patent specifications to avoid unintended disclaimers[4].

Litigation and Legal Precedents

The patent has been involved in several significant litigation cases:

• AstraZeneca v. Hanmi Pharmaceuticals and Amneal Pharmaceuticals: In this case, Hanmi and Amneal conceded the validity and enforceability of the patent but argued that their product did not infringe under the District Court's claim construction. AstraZeneca sought to appeal the claim construction, which they believed was erroneous[2].
• AstraZeneca v. Andrx Labs, LLC, and Perrigo Company: These cases involved similar disputes over claim construction and infringement, with the court ultimately adopting AstraZeneca's proposed construction for the claim terms[1].

Impact on Patent Landscape

The litigation and claim construction related to this patent have had broader implications for the patent landscape:

• Patent Scope and Quality: The debates over patent scope and quality are relevant here. The narrowing of claims during the examination process, as seen in this patent, aligns with research indicating that narrower claims are associated with a higher probability of grant and a shorter examination process[3].
• Innovation and Licensing: The patent's scope and the associated litigation costs can influence innovation and licensing strategies. Broader or overly broad patents can increase licensing and litigation costs, potentially diminishing incentives for innovation[3].

Patent Maintenance and Forward Citations

The maintenance and forward citations of this patent provide insights into its impact and relevance:

• Patent Maintenance Payments: The patent has required significant maintenance payments over the years, indicating its continued importance and value to AstraZeneca.
• Forward Citations: The patent has been cited in numerous subsequent patents, reflecting its influence on the development of related technologies and pharmaceuticals[3].

Industry Expert Insights

Industry experts emphasize the critical nature of claim drafting and specification writing:

• Kisuk Lee, a principal at Harness IP, notes that careful drafting of the specification is as important as good claim crafting for broader patent protection. Avoiding terms like "the present invention" can reduce the risks associated with disclaimer challenges[4].

Statistical Significance

Statistical analysis of patent scope metrics, such as independent claim length and count, supports the notion that narrower claims, like those in this patent, are more likely to be granted and have a shorter examination process[3].

Conclusion

The United States Patent 5,714,504 is a landmark patent in the pharmaceutical industry, particularly in the context of esomeprazole. The patent's claims, construction, and litigation history provide valuable lessons on patent scope, claim drafting, and the broader patent landscape.

Key Takeaways

• Narrow Claim Construction: The patent's claims have been narrowly construed to include only specific salts of esomeprazole.
• Importance of Specification: The specification's language can significantly impact claim scope and avoid unintended disclaimers.
• Litigation Impact: The patent has been central to several high-profile litigation cases, influencing the interpretation of claim terms.
• Patent Scope and Quality: The patent's history highlights the importance of narrower claims in the patent examination process.
• Industry Insights: Careful drafting of claims and specifications is crucial for maintaining broad patent protection.

FAQs

Q1: What is the primary subject matter of United States Patent 5,714,504? A1: The primary subject matter is the various salts of esomeprazole, particularly the sodium salt.

Q2: How has the term "alkaline salt" been construed in this patent? A2: The term "alkaline salt" has been narrowly construed to include only six specific salts mentioned in the specification.

Q3: What is the significance of the term "the present invention" in patent specifications? A3: The term can limit the claim scope to the specific embodiments described, potentially disclaiming other members of the class.

Q4: How has this patent impacted the broader patent landscape? A4: It has influenced debates on patent scope and quality, highlighting the importance of narrower claims and careful specification drafting.

Q5: What are some key metrics for measuring patent scope? A5: Independent claim length and independent claim count are simple yet effective metrics for measuring patent scope.

Sources

1. AstraZeneca AB, et al. v. Andrx Labs, LLC, et al., Civil Action No. 14-8030, Document 108, Filed 01/11/17.
2. AstraZeneca enters agreement with Hanmi Pharmaceuticals and Amneal Pharmaceuticals, AstraZeneca Press Release, June 3, 2013.
3. Patent Claims and Patent Scope, SSRN, September 29, 2016.
4. Don't call your invention “the present invention”, Harness IP Blog, February 24, 2014.
5. AstraZeneca AB v. Hanmi USA, Inc., Casetext.

Drugs Protected by US Patent 5,714,504

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate

Foreign Priority and PCT Information for Patent: 5,714,504

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Sweden	9301830	May 28, 1993

International Family Members for US Patent 5,714,504

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	1020461		C300482	Netherlands
European Patent Office	1020461		91870	Luxembourg
European Patent Office	1020461		300482	Netherlands