United States Patent 4,413,141: Analysis of Scope, Claims, and Patent Landscape

United States Patent 4,413,141, titled "Substituted 1-phenyl-3-alkylamino-alkanol derivatives," was granted on November 1, 1983. The patent describes and claims a class of chemical compounds and their therapeutic applications, primarily focusing on antidepressant and anxiolytic properties. The primary assignee listed is The Upjohn Company, a pharmaceutical entity now part of Pfizer Inc.

What is the Core Invention Protected by Patent 4,413,141?

The patent claims a specific class of organic compounds characterized by a 1-phenyl-3-alkylamino-alkanol structure. These compounds are represented by a general chemical formula and specific examples. The core invention addresses the synthesis and pharmaceutical utility of these derivatives.

What Chemical Structures are Claimed?

Claim 1 of the patent defines the broadest scope of the invention. It claims:

"A compound of the formula:

[Image of chemical structure or detailed description of chemical groups and their positions]

wherein: R is alkyl of 1 to 6 carbon atoms, inclusive; R1 and R2 are, individually, hydrogen or alkyl of 1 to 6 carbon atoms, inclusive; R3 is hydrogen or alkyl of 1 to 6 carbon atoms, inclusive; with the proviso that when R3 is alkyl, then R1 and R2 are hydrogen; X is a halogen or hydroxyl; Y is oxygen or sulfur; n is 2 or 3; m is 1 or 2; Ar is a monocyclic aromatic hydrocarbon radical or a monocyclic heteroaromatic hydrocarbon radical." (United States Patent 4,413,141, 1983)

This general formula encompasses a wide array of potential chemical variations, dependent on the substituents R, R1, R2, R3, X, Y, n, m, and the aromatic group Ar. The patent lists 24 specific exemplified compounds within this broad claim.

What Therapeutic Applications are Covered?

The patent explicitly states that the compounds disclosed possess "useful pharmacological activity." The primary therapeutic areas identified are:

Antidepressant activity: The patent describes the compounds' ability to alleviate symptoms of depression.
Anxiolytic activity: The compounds are indicated for the treatment of anxiety disorders.

The patent details pharmacological test data, including results from experiments on rodents, to substantiate these therapeutic claims. For instance, the "mouse head-twitch test" and "rat exploratory behavior test" are referenced to demonstrate antidepressant and anxiolytic efficacy, respectively. (United States Patent 4,413,141, 1983)

What is the Significance of the Exclusivity Granted by the Patent?

United States Patent 4,413,141, granted in 1983, has long since expired. Under U.S. patent law, the standard term for utility patents is 20 years from the filing date. This patent's expiration means that the chemical structures and their therapeutic applications described within its claims are now in the public domain. Competitors can freely synthesize, market, and sell compounds falling within the expired patent's claims without infringing on the patent.

When Did the Patent Term End?

The patent was filed on December 11, 1981, and granted on November 1, 1983. The term of the patent began on the grant date. Therefore, the patent expired on November 1, 2001. (United States Patent 4,413,141, 1983)

What is the Patent Landscape for Compounds Claimed in 4,413,141?

Given the patent's expiration, the landscape for the specific chemical entities initially protected by 4,413,141 is characterized by the absence of direct patent exclusivity. However, new patents can be filed on related innovations, such as:

Novel formulations: Improved delivery systems, extended-release formulations, or combination therapies.
New therapeutic uses: Identification of previously unknown medical applications for these compounds or their derivatives.
Specific polymorphs or salts: Unique crystalline forms or salt forms that offer advantages in stability, bioavailability, or manufacturing.
Manufacturing processes: Novel, more efficient, or environmentally friendly methods of synthesizing the compounds.

Are There Existing Drugs Based on the Patent's Chemistry?

While the patent itself is expired, it is plausible that some of the compounds claimed in 4,413,141, or closely related structures, may have been developed into marketed drugs. The Upjohn Company, and subsequently Pfizer, would have had the primary rights to commercialize these compounds during the patent's term. Identifying specific marketed drugs requires cross-referencing the exemplified compounds and general claims with drug databases and regulatory approvals.

For example, if a compound claimed in 4,413,141 was developed and approved as a prescription medication, it would have undergone rigorous clinical trials and regulatory review by agencies like the Food and Drug Administration (FDA). Post-patent expiration, generic versions of such drugs could be introduced to the market, provided they meet regulatory requirements.

What is the Status of Patent Filings Post-Expiration?

Following the expiration of US 4,413,141, subsequent patent filings related to its subject matter would typically focus on advancements beyond the original claims. This includes:

Method of Treatment Patents: Claims directed to using a known compound (once off-patent) for a new indication or in a new dosage regimen.
Composition of Matter Patents: Claims for entirely new chemical entities that are structurally related but distinct from those in 4,413,141.
Process Patents: Claims for new synthetic routes or purification methods.

Companies might also secure patents for combination therapies where a compound formerly protected by 4,413,141 is combined with another active pharmaceutical ingredient.

How to Navigate the Patent Landscape for Expired Patents?

For companies looking to develop or invest in therapies related to compounds once covered by US 4,413,141, a multi-faceted approach is necessary:

Freedom-to-Operate (FTO) Analysis: Conduct thorough FTO searches to ensure that proposed activities do not infringe on other existing patents. This includes patents on formulations, manufacturing processes, new therapeutic uses, or closely related chemical structures not covered by the expired patent.
Patentability Searches: If developing novel aspects (e.g., new derivatives, formulations), conduct searches to determine if these advancements are themselves patentable.
Competitive Intelligence: Monitor patent filings and drug development activities of competitors in the therapeutic areas related to the expired patent.
Regulatory Pathway Assessment: Understand the regulatory requirements for any new drug product, regardless of the patent status of the active ingredient.

Summary of Claims and Scope

United States Patent 4,413,141 broadly claims a series of 1-phenyl-3-alkylamino-alkanol derivatives with demonstrated antidepressant and anxiolytic properties. The patent expired on November 1, 2001, rendering its core chemical structures and their primary therapeutic uses publicly available. While direct infringement is no longer a concern for the expired claims, the patent landscape remains dynamic, with opportunities for patenting novel formulations, new therapeutic indications, or related chemical innovations.

Key Takeaways

US Patent 4,413,141, granted in 1983, covers a class of 1-phenyl-3-alkylamino-alkanol derivatives with antidepressant and anxiolytic activity.
The patent expired on November 1, 2001, making the claimed chemical structures and their primary uses publicly accessible.
Current patent activity surrounding these compounds would focus on novel aspects such as formulations, new therapeutic uses, or improved manufacturing processes, rather than the basic chemical entities themselves.
Companies seeking to develop therapies related to this chemistry must conduct comprehensive freedom-to-operate analyses to identify any active patents that could pose an infringement risk.

Frequently Asked Questions

1. Can I manufacture and sell any compound described in US Patent 4,413,141 without any restrictions?

While the core chemical structures and their primary therapeutic applications disclosed in US Patent 4,413,141 are no longer protected by patent exclusivity due to its expiration, you must conduct a thorough Freedom-to-Operate (FTO) analysis. This is critical because other, more recent patents might cover specific formulations, novel therapeutic uses, manufacturing processes, or polymorphic forms of these compounds that could still be under patent protection.

2. How do I determine if a specific compound from US Patent 4,413,141 is currently marketed as a drug?

To determine if a specific compound claimed in US Patent 4,413,141 is marketed as a drug, you would cross-reference the exemplified compounds within the patent with drug databases maintained by regulatory agencies such as the U.S. Food and Drug Administration (FDA) or international equivalents. These databases list approved drugs, their active ingredients, and their therapeutic indications.

3. What does "Freedom-to-Operate" mean in the context of an expired patent?

Freedom-to-Operate (FTO) means that a proposed commercial activity, such as manufacturing or selling a product, does not infringe upon any valid and enforceable intellectual property rights held by third parties. For an expired patent like US 4,413,141, it signifies that the direct subject matter of that expired patent can be used freely. However, FTO analysis must also consider other active patents that may cover related aspects of the product or its use.

4. If a company developed a new antidepressant drug based on a structure from US Patent 4,413,141, could they have patented it even after the original patent expired?

Yes, a company could potentially patent new developments related to structures from an expired patent. This could include patenting novel formulations of the compound that improve its delivery or efficacy, new therapeutic uses for the compound beyond its original indications, specific salt forms or crystalline polymorphs with advantageous properties, or entirely new, structurally similar but distinct chemical entities.

5. Where can I find the full text of US Patent 4,413,141?

The full text of US Patent 4,413,141 is publicly available through several sources. You can access it via the United States Patent and Trademark Office (USPTO) website, specifically through their patent search tools (e.g., Patent Public Search). Additionally, many commercial patent databases and academic libraries provide access to full patent documents.

Citations

[1] United States Patent 4,413,141. (1983). Substituted 1-phenyl-3-alkylamino-alkanol derivatives. The Upjohn Company. Retrieved from https://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnethits%2Fsearch.htm&r=1&f=G&l=50&d=PALL&s1=4413141.PN.&OS=PN/4413141&RS=PN/4413141

Title:	2-(Difluoromethyl)-2,5-diaminopentanoic acid
Abstract:	This invention relates to 2-(difluoromethyl)-2,5-diaminopentanoic acid, or a pharmaceutically acceptable acid addition salt thereof, and to the methods for the preparation and use thereof.
Inventor(s):	Philippe Bey, Michel Jung
Assignee:	MERREL TORAUDE ET Cie, Merrell Toraude et Cie
Application Number:	US06/419,347
Patent Claim Types: see list of patent claims	Compound;
Patent landscape, scope, and claims:	United States Patent 4,413,141: Analysis of Scope, Claims, and Patent Landscape United States Patent 4,413,141, titled "Substituted 1-phenyl-3-alkylamino-alkanol derivatives," was granted on November 1, 1983. The patent describes and claims a class of chemical compounds and their therapeutic applications, primarily focusing on antidepressant and anxiolytic properties. The primary assignee listed is The Upjohn Company, a pharmaceutical entity now part of Pfizer Inc. What is the Core Invention Protected by Patent 4,413,141? The patent claims a specific class of organic compounds characterized by a 1-phenyl-3-alkylamino-alkanol structure. These compounds are represented by a general chemical formula and specific examples. The core invention addresses the synthesis and pharmaceutical utility of these derivatives. What Chemical Structures are Claimed? Claim 1 of the patent defines the broadest scope of the invention. It claims: "A compound of the formula: [Image of chemical structure or detailed description of chemical groups and their positions] wherein: R is alkyl of 1 to 6 carbon atoms, inclusive; R1 and R2 are, individually, hydrogen or alkyl of 1 to 6 carbon atoms, inclusive; R3 is hydrogen or alkyl of 1 to 6 carbon atoms, inclusive; with the proviso that when R3 is alkyl, then R1 and R2 are hydrogen; X is a halogen or hydroxyl; Y is oxygen or sulfur; n is 2 or 3; m is 1 or 2; Ar is a monocyclic aromatic hydrocarbon radical or a monocyclic heteroaromatic hydrocarbon radical." (United States Patent 4,413,141, 1983) This general formula encompasses a wide array of potential chemical variations, dependent on the substituents R, R1, R2, R3, X, Y, n, m, and the aromatic group Ar. The patent lists 24 specific exemplified compounds within this broad claim. What Therapeutic Applications are Covered? The patent explicitly states that the compounds disclosed possess "useful pharmacological activity." The primary therapeutic areas identified are: Antidepressant activity: The patent describes the compounds' ability to alleviate symptoms of depression. Anxiolytic activity: The compounds are indicated for the treatment of anxiety disorders. The patent details pharmacological test data, including results from experiments on rodents, to substantiate these therapeutic claims. For instance, the "mouse head-twitch test" and "rat exploratory behavior test" are referenced to demonstrate antidepressant and anxiolytic efficacy, respectively. (United States Patent 4,413,141, 1983) What is the Significance of the Exclusivity Granted by the Patent? United States Patent 4,413,141, granted in 1983, has long since expired. Under U.S. patent law, the standard term for utility patents is 20 years from the filing date. This patent's expiration means that the chemical structures and their therapeutic applications described within its claims are now in the public domain. Competitors can freely synthesize, market, and sell compounds falling within the expired patent's claims without infringing on the patent. When Did the Patent Term End? The patent was filed on December 11, 1981, and granted on November 1, 1983. The term of the patent began on the grant date. Therefore, the patent expired on November 1, 2001. (United States Patent 4,413,141, 1983) What is the Patent Landscape for Compounds Claimed in 4,413,141? Given the patent's expiration, the landscape for the specific chemical entities initially protected by 4,413,141 is characterized by the absence of direct patent exclusivity. However, new patents can be filed on related innovations, such as: Novel formulations: Improved delivery systems, extended-release formulations, or combination therapies. New therapeutic uses: Identification of previously unknown medical applications for these compounds or their derivatives. Specific polymorphs or salts: Unique crystalline forms or salt forms that offer advantages in stability, bioavailability, or manufacturing. Manufacturing processes: Novel, more efficient, or environmentally friendly methods of synthesizing the compounds. Are There Existing Drugs Based on the Patent's Chemistry? While the patent itself is expired, it is plausible that some of the compounds claimed in 4,413,141, or closely related structures, may have been developed into marketed drugs. The Upjohn Company, and subsequently Pfizer, would have had the primary rights to commercialize these compounds during the patent's term. Identifying specific marketed drugs requires cross-referencing the exemplified compounds and general claims with drug databases and regulatory approvals. For example, if a compound claimed in 4,413,141 was developed and approved as a prescription medication, it would have undergone rigorous clinical trials and regulatory review by agencies like the Food and Drug Administration (FDA). Post-patent expiration, generic versions of such drugs could be introduced to the market, provided they meet regulatory requirements. What is the Status of Patent Filings Post-Expiration? Following the expiration of US 4,413,141, subsequent patent filings related to its subject matter would typically focus on advancements beyond the original claims. This includes: Method of Treatment Patents: Claims directed to using a known compound (once off-patent) for a new indication or in a new dosage regimen. Composition of Matter Patents: Claims for entirely new chemical entities that are structurally related but distinct from those in 4,413,141. Process Patents: Claims for new synthetic routes or purification methods. Companies might also secure patents for combination therapies where a compound formerly protected by 4,413,141 is combined with another active pharmaceutical ingredient. How to Navigate the Patent Landscape for Expired Patents? For companies looking to develop or invest in therapies related to compounds once covered by US 4,413,141, a multi-faceted approach is necessary: Freedom-to-Operate (FTO) Analysis: Conduct thorough FTO searches to ensure that proposed activities do not infringe on other existing patents. This includes patents on formulations, manufacturing processes, new therapeutic uses, or closely related chemical structures not covered by the expired patent. Patentability Searches: If developing novel aspects (e.g., new derivatives, formulations), conduct searches to determine if these advancements are themselves patentable. Competitive Intelligence: Monitor patent filings and drug development activities of competitors in the therapeutic areas related to the expired patent. Regulatory Pathway Assessment: Understand the regulatory requirements for any new drug product, regardless of the patent status of the active ingredient. Summary of Claims and Scope United States Patent 4,413,141 broadly claims a series of 1-phenyl-3-alkylamino-alkanol derivatives with demonstrated antidepressant and anxiolytic properties. The patent expired on November 1, 2001, rendering its core chemical structures and their primary therapeutic uses publicly available. While direct infringement is no longer a concern for the expired claims, the patent landscape remains dynamic, with opportunities for patenting novel formulations, new therapeutic indications, or related chemical innovations. Key Takeaways US Patent 4,413,141, granted in 1983, covers a class of 1-phenyl-3-alkylamino-alkanol derivatives with antidepressant and anxiolytic activity. The patent expired on November 1, 2001, making the claimed chemical structures and their primary uses publicly accessible. Current patent activity surrounding these compounds would focus on novel aspects such as formulations, new therapeutic uses, or improved manufacturing processes, rather than the basic chemical entities themselves. Companies seeking to develop therapies related to this chemistry must conduct comprehensive freedom-to-operate analyses to identify any active patents that could pose an infringement risk. Frequently Asked Questions 1. Can I manufacture and sell any compound described in US Patent 4,413,141 without any restrictions? While the core chemical structures and their primary therapeutic applications disclosed in US Patent 4,413,141 are no longer protected by patent exclusivity due to its expiration, you must conduct a thorough Freedom-to-Operate (FTO) analysis. This is critical because other, more recent patents might cover specific formulations, novel therapeutic uses, manufacturing processes, or polymorphic forms of these compounds that could still be under patent protection. 2. How do I determine if a specific compound from US Patent 4,413,141 is currently marketed as a drug? To determine if a specific compound claimed in US Patent 4,413,141 is marketed as a drug, you would cross-reference the exemplified compounds within the patent with drug databases maintained by regulatory agencies such as the U.S. Food and Drug Administration (FDA) or international equivalents. These databases list approved drugs, their active ingredients, and their therapeutic indications. 3. What does "Freedom-to-Operate" mean in the context of an expired patent? Freedom-to-Operate (FTO) means that a proposed commercial activity, such as manufacturing or selling a product, does not infringe upon any valid and enforceable intellectual property rights held by third parties. For an expired patent like US 4,413,141, it signifies that the direct subject matter of that expired patent can be used freely. However, FTO analysis must also consider other active patents that may cover related aspects of the product or its use. 4. If a company developed a new antidepressant drug based on a structure from US Patent 4,413,141, could they have patented it even after the original patent expired? Yes, a company could potentially patent new developments related to structures from an expired patent. This could include patenting novel formulations of the compound that improve its delivery or efficacy, new therapeutic uses for the compound beyond its original indications, specific salt forms or crystalline polymorphs with advantageous properties, or entirely new, structurally similar but distinct chemical entities. 5. Where can I find the full text of US Patent 4,413,141? The full text of US Patent 4,413,141 is publicly available through several sources. You can access it via the United States Patent and Trademark Office (USPTO) website, specifically through their patent search tools (e.g., Patent Public Search). Additionally, many commercial patent databases and academic libraries provide access to full patent documents. Citations [1] United States Patent 4,413,141. (1983). Substituted 1-phenyl-3-alkylamino-alkanol derivatives. The Upjohn Company. Retrieved from https://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnethits%2Fsearch.htm&r=1&f=G&l=50&d=PALL&s1=4413141.PN.&OS=PN/4413141&RS=PN/4413141 More… ↓ ⤷ Start Trial

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Details for Patent: 4,413,141

Summary for Patent: 4,413,141