United States Patent 5,686,104: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 5,686,104, hereafter referred to as the '104 patent, is one of the key patents associated with the pharmaceutical drug atorvastatin, marketed by Pfizer under the brand name Lipitor®. This patent is part of a complex patent landscape that has been the subject of numerous legal and regulatory discussions.
Background of the Patent
The '104 patent is one of several patents listed in the FDA's Orange Book for Lipitor®, a statin used to lower cholesterol levels. The patent was issued to Pfizer and is part of the broader intellectual property protection strategy for atorvastatin[2][4].
Patent Claims and Scope
Claim Structure
The '104 patent includes multiple claims that define the scope of the invention. These claims are categorized into independent and dependent claims. Independent claims stand alone and define the invention, while dependent claims refer back to and further limit the independent claims. The scope of the patent is determined by the language of these claims, which must meet the statutory requirements for patentability under Title 35 of the United States Code[3].
Independent Claim Length and Count
Research has shown that the length and count of independent claims can be indicative of patent scope. Shorter independent claims and fewer independent claims generally suggest a narrower patent scope, which can be associated with a higher probability of grant and a shorter examination process[3].
Specific Claims of the '104 Patent
The '104 patent covers specific aspects of atorvastatin, including its chemical structure, methods of synthesis, and pharmaceutical compositions. For instance, the patent claims the compound atorvastatin and its various salts, as well as methods for preparing these compounds. These claims are crucial in defining what is protected under the patent and what would constitute infringement[2].
Patent Landscape and Exclusivities
Orange Book Listings
The '104 patent is listed in the FDA's Orange Book, which compiles patent information for approved drugs. This listing is critical because it affects the timing of generic drug approvals. Generic drug manufacturers must certify to the FDA regarding the patents listed in the Orange Book, including whether they believe the patent is invalid, not infringed, or will expire before their generic product is approved[2][4].
Follow-On Patents and Exclusivities
The '104 patent is part of a broader strategy that includes follow-on patents. These patents cover improvements or modifications to the original drug, such as new dosage forms or methods of use. Follow-on patents can extend the market exclusivity period for the drug beyond the expiration of the original patent, a practice that has been subject to scrutiny and regulatory analysis[4].
Litigation and Legal Challenges
Pfizer Inc. v. Apotex Inc.
The '104 patent has been at the center of significant litigation, particularly in the case of Pfizer Inc. v. Apotex Inc. Apotex, a generic drug manufacturer, filed an Abbreviated New Drug Application (ANDA) to market a generic version of Lipitor®, prompting Pfizer to sue for patent infringement. Apotex counterclaimed, asserting the invalidity and non-infringement of the '104 patent, among others. The court denied Pfizer's motion to dismiss these counterclaims, allowing the case to proceed[2].
Paragraph IV Certifications
Generic drug applicants often file Paragraph IV certifications with the FDA, stating that the listed patents are invalid, unenforceable, or will not be infringed by their generic product. This certification can trigger litigation within 45 days, as seen in the case involving Dr. Reddy’s Laboratories Limited and Pfizer[1].
Impact on Generic Drug Approval
Delayed Generic Entry
The presence of the '104 patent and other related patents in the Orange Book can delay the entry of generic versions of atorvastatin into the market. Generic manufacturers must wait for the patents to expire or successfully challenge them in court before they can receive FDA approval for their products[2][4].
Regulatory Framework
The Hatch-Waxman Act and subsequent amendments, such as the Medicare Prescription Drug, Improvement, and Modernization Act of 2003, govern the interaction between patent protection and generic drug approval. These laws aim to balance innovation with public access to affordable drugs by providing a framework for generic drug applications and the resolution of patent disputes[2].
Economic and Innovation Implications
Patent Quality and Innovation
The scope and clarity of patent claims, such as those in the '104 patent, are critical for innovation. Broad or unclear claims can lead to increased litigation and licensing costs, potentially stifling innovation. Conversely, well-defined claims can provide clear boundaries for competitors and encourage further innovation[3].
Market Exclusivity and Competition
The '104 patent, along with other patents and exclusivities, influences the competitive landscape of the pharmaceutical market. Market exclusivity periods, extended by follow-on patents, can impact the timing and cost of generic drug entry, affecting consumer prices and access to medications[4].
Key Takeaways
- Patent Scope and Claims: The '104 patent's scope is defined by its claims, which must meet statutory requirements for patentability.
- Litigation and Certifications: The patent has been subject to significant litigation and Paragraph IV certifications by generic drug manufacturers.
- Impact on Generic Drugs: The patent delays generic entry into the market, affecting consumer access and prices.
- Regulatory Framework: The Hatch-Waxman Act and related laws govern the balance between innovation and public access to drugs.
- Economic Implications: Clear and well-defined patent claims are crucial for promoting innovation and managing litigation costs.
FAQs
What is the '104 patent, and what does it cover?
The '104 patent, or United States Patent 5,686,104, covers aspects of the pharmaceutical drug atorvastatin, including its chemical structure, methods of synthesis, and pharmaceutical compositions.
How does the '104 patent affect generic drug approval?
The '104 patent, listed in the FDA's Orange Book, requires generic drug manufacturers to certify that the patent is invalid, unenforceable, or will not be infringed by their product. This can lead to litigation and delay the approval of generic versions of atorvastatin.
What is the significance of follow-on patents in the context of the '104 patent?
Follow-on patents can extend the market exclusivity period for atorvastatin beyond the expiration of the original patent, affecting the timing and cost of generic drug entry.
How does the Hatch-Waxman Act impact the '104 patent and generic drug approval?
The Hatch-Waxman Act provides a framework for generic drug applications and the resolution of patent disputes, balancing innovation with public access to affordable drugs.
What are the economic implications of the '104 patent on the pharmaceutical market?
The '104 patent and related exclusivities influence the competitive landscape, affecting consumer prices and access to medications. Clear and well-defined patent claims are crucial for promoting innovation and managing litigation costs.
Sources
- FDA Document: Atorvastatin Calcium Tablets, 80 mg (base) - accessdata.fda.gov
- Casetext: Pfizer Inc. v. Apotex Inc. - Casetext
- Hoover Institution: Patent Claims and Patent Scope - Hoover Institution
- USPTO-FDA Report: USPTO-FDA Report on Drug Patent and Exclusivity - USPTO
