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Critical Analysis of US Patent 6,037,361 Claim Scope and the U.S. Patent Landscape

US Patent 6,037,361 is a U.S. small-molecule composition-of-matter and broad method-of-use patent built around Formula I compounds with dibenzofuran or dibenzothiophene-type aryl scaffolds bearing difluoro substitution patterns and α-oxo/α-hydroxyimino and acid/amidic functional groups (plus prodrugs and salts). The claims are dense but commercially oriented: they cover a wide genus of fluorinated metalloproteinase (MMP) inhibitors and then expand into many disease areas where MMP activity is implicated, using functional language at the disease level.

This estate can create substantial entry friction for generic or follow-on developers because (1) claim 1 is a genus with multiple substituent positions and multiple allowed heteroaryl/aryl and linker options, (2) dependent claims narrow to particular Y linkers and specific fluorinated acid sub-genuses, and (3) the methods claims are framed as inhibition of specific MMPs (gelatinase A, stromelysin-1, collagenase, matrilysin, MMP-13) and as treatment/prevention of plaque rupture, restenosis, and a broad set of inflammatory, wound-healing, ocular, autoimmune, neurodegenerative and cancer indications.

What patents protect US 6,037,361 Formula I metalloproteinase inhibitors?

Answer: US 6,037,361 protects (i) Formula I compounds and their isomers, prodrugs, and salts, (ii) pharmaceutical compositions, and (iii) methods of inhibiting MMPs and treating/preventing a wide set of diseases tied to tissue invasion and matrix remodeling.

What is the core claim technology in claim 1?

Claim 1 recites:

A compound of Formula I, where one of R or R¹ is hydrogen and the other is a substituent incorporating:
- A dibenzofuran- or dibenzothiophene-type fused aryl core (as illustrated in the specific examples in claim 7).
- A difluorinated carbon center pattern and a functional “tail” enabling activity (acid, hydroxyimino, thioxo, amide, and related motifs).
A mandatory structural proviso:
- At least one of R³, R³a, R⁴, or R⁴a is fluorine
- At least one of R⁷ and R⁸ is fluorine
Allowed “decorations” at multiple positions:
- R⁶ can be hydrogen, alkyl, short alkyl-aryl, or short alkyl-cycloalkyl, plus a phthalimido or heteroaryl variant.
- R² and R²a can include hydrogen, alkyl, alkoxy, halogen, hydroxy, cyano, nitro, and trifluoromethyl plus carboxy (CO₂R⁹), carbonyl (COR⁹), sulfonate (--SO₃R⁹), and dialkylamino-methylene (--(CH₂)nN(R⁹)₂) motifs (as permitted by R⁹ definitions).
- Y is a linkage chosen from carbon-oxygen and sulfoxide/sulfone-like oxygen-sulfur patterns and/or other Y-defined link types shown in the claim.

How broad is the genus in practical freedom-to-operate terms?

Claim 1 is broad in three ways that matter for generics and licensing:

Substitution latitude: multiple substituent positions are variable within defined chemical families (alkyl/aryl/heteroaryl, electron-withdrawing groups like cyano/nitro/trifluoromethyl, and polar anions like sulfonate/carboxylate precursors via R⁹).
Linkage variability: Y includes multiple oxygen/sulfur-related options.
Functional end states: prodrugs and salts are explicitly included, which expands coverage to common formulation-following derivatives rather than only the free acids.

This structure makes it easier for an inventor in the same chemical family to land “inside” the same claim 1 genus, even if they avoid specific embodiments named later.

What do the dependent claims add?

Claim 2 adds a further constraint: R is a specific substituent class and Y is restricted to --O-- or --CH₂--.
Claim 3 locks R¹, R², R²a = hydrogen.
Claims 4–6 narrow to specific substructures (with Z and specific fluorine/hydrogen arrangements), including R⁵ = OH and Z variants.
Claim 7 provides a long, explicit list of specific compounds (and isomers) that fall within claim 1’s genus.

From an enforcement perspective, claim 7’s enumerated examples create a clean set of “anchor” molecules for claim construction and validity arguments, because you can map real structures into the claim language without relying solely on interpretive flexibility.

Which exact compounds are named in claim 7, and why does that matter?

Answer: Claim 7 lists a set of specific fluorinated dibenzofuran/dibenzothiophene acids, hydroxyimino variants, thioxo variants, enone (“but-2-enoic”) variants, and specific aryl-substituted analogs, each with difluoro patterns and acid or amide functional groups, plus “corresponding isomers,” prodrugs and salts.

Named embodiments (examples in claim 7)

The claim includes compounds such as:

2-Benzyl-4-dibenzofuran-2-yl-3,3-difluoro-4-oxo-butyric acid
4-Dibenzofuran-2-yl-3,3-difluoro-4-hydroxyimino-butyric acid
4-Dibenzofuran-2-yl-3,3-difluoro-N-hydroxy-4-oxo-butyramide
4-Dibenzofuran-2-yl-3-fluoro-4-oxo-but-2-enoic acid
4-Dibenzofuran-2-yl-3,3-difluoro-4-thioxo-butyric acid
4-(7-Bromo-dibenzofuran-2-yl)-3,3-difluoro-4-oxo-butyric acid
4-(9H-Fluoren-2-yl)-3,3-difluoro-4-oxo-butyric acid
4-(9H-Fluoren-3-yl)-2,2-difluoro-4-hydroxyimino-butyric acid
4-Dibenzothiophene-2-yl-2,2,3,3-tetrafluoro-4-oxo-butyric acid
4-(9H-Carbazol-2-yl)-2,2-difluoro-4-hydroxyimino-butyric acid
4-(7-nitrodibenzofuran-2-yl)-3-fluoro-4-(…)-butyric acid (as listed)
Multiple other fluorinated analogs, including dibenzofuran carbonyl substitutions and phenethyl-linked variants.

Why listing matters for enforcement and validity

Claim 7 is a “structure-to-claim” bridge: enforcement can focus on whether a product matches one of the listed chemical identities (or a close variant captured by “corresponding isomers” and the genus language of claim 1).
In validity challenges, enumerated examples also support enablement and written description arguments because you can tie the disclosure directly to claimed species and narrow to subgenuses.
For design-arounds, claim 7 means a developer cannot simply rely on “we avoid the obvious named structures.” The claim 1 genus still captures many nearby alternatives unless they exit the specific substituent families and fluorine/linkage constraints.

What methods claims does US 6,037,361 include, and how might they expand infringement?

Answer: The patent includes methods of inhibiting specific MMPs (matrix metalloproteinase, gelatinase A, stromelysin-1, collagenase, matrilysin, MMP-13) and then expands to prevention/treatment of indications including atherosclerotic plaque rupture, aortic aneurysm, heart failure, restenosis, periodontal disease, corneal ulceration, burns, decubital ulcers, wound healing, and cancer, plus arthritis, autoimmune/inflammatory disorders, multiple sclerosis, inflammation and pain, and a list of neurodegenerative disorders (stroke, head trauma, spinal cord injury, Alzheimer’s, ALS, cerebral amyloid angiopathy, AIDS, Parkinson’s, Huntington’s, prion diseases, myasthenia gravis, Duchenne muscular dystrophy).

How the methods are drafted

Claims 10–15 are crisp: “method of inhibiting [MMP] comprising administering… a compound according to claim 1… in unit dosage form.”
Claims 16–30 broaden the medical narrative but keep the legal hook as “administering” a compound according to claim 1 for prevention or treatment.

Litigation risk pattern if a competitor sells an MMP inhibitor in this class

If a marketed product uses a compound that falls under claim 1’s genus, then:

Direct infringement exposure arises from clinical use and label/indication alignment with claims 16–30.
Inducement/contributory exposure can arise even without identical disease language, because the methods claims are framed around administration to hosts suffering from listed conditions, but proof typically leans on evidence of use for those conditions.

What is the composition-of-matter and formulation coverage in US 6,037,361?

Answer: The patent includes pharmaceutical compositions as claim 31–32: a compound according to claim 1 in admixture with pharmaceutically acceptable excipient/diluent/carrier, with and without specifying “therapeutically effective amount.”

Why this matters for generics and follow-on formulations

Even if an applicant changes the formulation (tablet vs capsule, salt form vs free acid, excipient choice), the composition claims can still cover them if the active ingredient is within claim 1.
The explicit mention of prodrugs and salts in claim 1 also makes it harder to avoid infringement by selecting alternative salt forms, unless the candidate active ingredient exits the claim 1 structure boundaries.

How strong is the patent estate for this chemical series in the U.S.?

Answer: Based on the claims alone, US 6,037,361 has high structural coverage (broad genus plus fluorine/linkage constraints) and broad use coverage (multiple MMPs and many indications). The estate’s strength relative to competitors will depend on whether later continuations, divisionals, or related patents exist in the same filing family that capture:

additional substituent positions,
different prodrug/salt forms,
alternative crystalline forms,
additional method-of-use refinements,
and whether claims are supported by robust experimental data in the specification.

This analysis cannot map the full family without the application/patent history, publication numbers, and other U.S. patents in the same priority chain.

What generic entry risks exist for products that target MMPs using similar fluorinated dibenzofuran motifs?

Answer: If a generic or follow-on applicant’s active ingredient is within claim 1, then generic launch is blocked at least by the composition and genus coverage, and may also be blocked by method-of-use risk depending on FDA labeling and actual use.

Where design-arounds typically fail against this claim set

Avoiding named examples in claim 7 is insufficient due to genus coverage.
Escaping fluorine constraints is difficult because claim 1 expressly requires fluorine at defined positions (at least one of R³/R³a/R⁴/R⁴a and at least one of R⁷/R⁸).
Changing Y to an unlisted linkage may work, but claim 1 includes multiple Y options and dependent claims still cover “Y = --O-- or --CH₂--” plus other substructures.

Practical consequence for a challenger

A developer would need to ensure the active ingredient structure falls outside:

the dibenzofuran/dibenzothiophene linked scaffolding as defined by Formula I,
the difluoro/hydroxyimino/oxo or related functional motif set,
and the Y and fluorine provisos.

What are the likely infringement “claim mapping” hotspots?

Answer: The easiest-to-prove claim elements against accused products are the structural provisos and the functional group class.

Hotspots within claim 1

Fluorine proviso: proving R³/R³a/R⁴/R⁴a includes a fluorine and R⁷/R⁸ includes a fluorine.
Y linkage: proving the accused structure’s oxygen/sulfur motif matches one of the defined Y variants.
Functional “acid/oxo/hydroxyimino/amido” region: proving the accused molecule includes the acid/oxo/hydroxyimino/thioxo/but-2-enoic equivalents that correspond to the claim’s Formula I and substituent options.
R⁶ and aryl/heteroaryl side options: proving the correct allowed categories for R⁶, particularly the inclusion/exclusion of N-phthalimido and heteroaryl options.

Key Takeaways

US 6,037,361 is a broad genus patent for fluorinated dibenzofuran/dibenzothiophene-derived metalloproteinase inhibitors with defined fluorine constraints, plus prodrugs and salts.
Enforcement leverage is two-tiered: claim 1 covers the chemical space, while claims 10–30 cover administration for inhibition of specific MMPs and for many matrix remodeling and inflammation-linked diseases.
Named species in claim 7 materially assist claim construction and reduce ambiguity by providing concrete structures within the broader genus.
Design-arounds face structural barriers because fluorine and linkage constraints are built into claim 1, not left purely optional.
The true magnitude of the enforceable U.S. landscape depends on the family (continuations/divisionals) and the existence of other patents covering related salts, prodrugs, and follow-on formulations, which are not determinable from the claim text alone.

FAQs

1) Does US 6,037,361 cover prodrugs and salts?
Yes. Claim 1 expressly includes “pharmaceutically acceptable prodrug” and “pharmaceutically acceptable salt” of the Formula I compounds.

2) Which MMP targets are explicitly named in the methods claims?
Matrix metalloproteinase (general) plus gelatinase A, stromelysin-1, collagenase, matrilysin, and MMP-13.

3) Are both compound and method of treatment claims present?
Yes. The patent includes compound claims (genus/formula, plus specific species) and multiple method-of-use claims tied to MMP inhibition and disease treatment/prevention.

4) Do the dependent claims narrow “Y” to specific linkages?
Yes. Claim 2 restricts Y to --O-- or --CH₂--.

5) What is the practical workaround most likely to fail against this patent?
Changing only excipients or switching among salt forms of a compound that still falls within claim 1’s Formula I and fluorine/linkage constraints.

References

US Patent 6,037,361 (claims text provided in prompt).

Title:	Fluorinated butyric acids and their derivatives as inhibitors of matrix metalloproteinases
Abstract:	Fluorinated butyric acid compounds and derivatives are described as well as acid methods for the preparation and pharmaceutical compositions of same, which are useful as inhibitors of matrix metalloproteinases, particularly gelatinase A (72 kD gelatinase) and stromelysin-1, and also collagenase, matrilysin, and MMP-13, and for the treatment of multiple sclerosis, atherosclerotic plaque rupture, aortic aneurism, heart failure, restenosis, periodontal disease, corneal ulceration, treatment of burns, decubital ulcers, wound healing, cancer, inflammation, pain, arthritis, or other autoimmune or inflammatory disorders dependent upon tissue invasion by leukocytes or other activated migrating cells, acute and chronic neurodegenerative disorders including stroke, head trauma, spinal cord injury, Alzheimer\'s disease, amyotrophic lateral sclerosis, cerebral amyloid angiopathy, AIDS, Parkinson\'s disease, Huntington\'s disease, prion diseases, myasthenia gravis, and Duchenne\'s muscular dystrophy.
Inventor(s):	Roth; Bruce David (Plymouth, MI), O\'Brien; Patrick Michael (Stockbridge, MI), Sliskovic; Drago Robert (Saline, MI)
Assignee:	Warner-Lambert Company (Ann Arbor, MI)
Application Number:	09/036,751
Patent Claims:	see list of patent claims
Patent landscape, scope, and claims summary:	Critical Analysis of US Patent 6,037,361 Claim Scope and the U.S. Patent Landscape US Patent 6,037,361 is a U.S. small-molecule composition-of-matter and broad method-of-use patent built around Formula I compounds with dibenzofuran or dibenzothiophene-type aryl scaffolds bearing difluoro substitution patterns and α-oxo/α-hydroxyimino and acid/amidic functional groups (plus prodrugs and salts). The claims are dense but commercially oriented: they cover a wide genus of fluorinated metalloproteinase (MMP) inhibitors and then expand into many disease areas where MMP activity is implicated, using functional language at the disease level. This estate can create substantial entry friction for generic or follow-on developers because (1) claim 1 is a genus with multiple substituent positions and multiple allowed heteroaryl/aryl and linker options, (2) dependent claims narrow to particular Y linkers and specific fluorinated acid sub-genuses, and (3) the methods claims are framed as inhibition of specific MMPs (gelatinase A, stromelysin-1, collagenase, matrilysin, MMP-13) and as treatment/prevention of plaque rupture, restenosis, and a broad set of inflammatory, wound-healing, ocular, autoimmune, neurodegenerative and cancer indications. What patents protect US 6,037,361 Formula I metalloproteinase inhibitors? Answer: US 6,037,361 protects (i) Formula I compounds and their isomers, prodrugs, and salts, (ii) pharmaceutical compositions, and (iii) methods of inhibiting MMPs and treating/preventing a wide set of diseases tied to tissue invasion and matrix remodeling. What is the core claim technology in claim 1? Claim 1 recites: A compound of Formula I, where one of R or R¹ is hydrogen and the other is a substituent incorporating: A dibenzofuran- or dibenzothiophene-type fused aryl core (as illustrated in the specific examples in claim 7). A difluorinated carbon center pattern and a functional “tail” enabling activity (acid, hydroxyimino, thioxo, amide, and related motifs). A mandatory structural proviso: At least one of R³, R³a, R⁴, or R⁴a is fluorine At least one of R⁷ and R⁸ is fluorine Allowed “decorations” at multiple positions: R⁶ can be hydrogen, alkyl, short alkyl-aryl, or short alkyl-cycloalkyl, plus a phthalimido or heteroaryl variant. R² and R²a can include hydrogen, alkyl, alkoxy, halogen, hydroxy, cyano, nitro, and trifluoromethyl plus carboxy (CO₂R⁹), carbonyl (COR⁹), sulfonate (--SO₃R⁹), and dialkylamino-methylene (--(CH₂)nN(R⁹)₂) motifs (as permitted by R⁹ definitions). Y is a linkage chosen from carbon-oxygen and sulfoxide/sulfone-like oxygen-sulfur patterns and/or other Y-defined link types shown in the claim. How broad is the genus in practical freedom-to-operate terms? Claim 1 is broad in three ways that matter for generics and licensing: Substitution latitude: multiple substituent positions are variable within defined chemical families (alkyl/aryl/heteroaryl, electron-withdrawing groups like cyano/nitro/trifluoromethyl, and polar anions like sulfonate/carboxylate precursors via R⁹). Linkage variability: Y includes multiple oxygen/sulfur-related options. Functional end states: prodrugs and salts are explicitly included, which expands coverage to common formulation-following derivatives rather than only the free acids. This structure makes it easier for an inventor in the same chemical family to land “inside” the same claim 1 genus, even if they avoid specific embodiments named later. What do the dependent claims add? Claim 2 adds a further constraint: R is a specific substituent class and Y is restricted to --O-- or --CH₂--. Claim 3 locks R¹, R², R²a = hydrogen. Claims 4–6 narrow to specific substructures (with Z and specific fluorine/hydrogen arrangements), including R⁵ = OH and Z variants. Claim 7 provides a long, explicit list of specific compounds (and isomers) that fall within claim 1’s genus. From an enforcement perspective, claim 7’s enumerated examples create a clean set of “anchor” molecules for claim construction and validity arguments, because you can map real structures into the claim language without relying solely on interpretive flexibility. Which exact compounds are named in claim 7, and why does that matter? Answer: Claim 7 lists a set of specific fluorinated dibenzofuran/dibenzothiophene acids, hydroxyimino variants, thioxo variants, enone (“but-2-enoic”) variants, and specific aryl-substituted analogs, each with difluoro patterns and acid or amide functional groups, plus “corresponding isomers,” prodrugs and salts. Named embodiments (examples in claim 7) The claim includes compounds such as: 2-Benzyl-4-dibenzofuran-2-yl-3,3-difluoro-4-oxo-butyric acid 4-Dibenzofuran-2-yl-3,3-difluoro-4-hydroxyimino-butyric acid 4-Dibenzofuran-2-yl-3,3-difluoro-N-hydroxy-4-oxo-butyramide 4-Dibenzofuran-2-yl-3-fluoro-4-oxo-but-2-enoic acid 4-Dibenzofuran-2-yl-3,3-difluoro-4-thioxo-butyric acid 4-(7-Bromo-dibenzofuran-2-yl)-3,3-difluoro-4-oxo-butyric acid 4-(9H-Fluoren-2-yl)-3,3-difluoro-4-oxo-butyric acid 4-(9H-Fluoren-3-yl)-2,2-difluoro-4-hydroxyimino-butyric acid 4-Dibenzothiophene-2-yl-2,2,3,3-tetrafluoro-4-oxo-butyric acid 4-(9H-Carbazol-2-yl)-2,2-difluoro-4-hydroxyimino-butyric acid 4-(7-nitrodibenzofuran-2-yl)-3-fluoro-4-(…)-butyric acid (as listed) Multiple other fluorinated analogs, including dibenzofuran carbonyl substitutions and phenethyl-linked variants. Why listing matters for enforcement and validity Claim 7 is a “structure-to-claim” bridge: enforcement can focus on whether a product matches one of the listed chemical identities (or a close variant captured by “corresponding isomers” and the genus language of claim 1). In validity challenges, enumerated examples also support enablement and written description arguments because you can tie the disclosure directly to claimed species and narrow to subgenuses. For design-arounds, claim 7 means a developer cannot simply rely on “we avoid the obvious named structures.” The claim 1 genus still captures many nearby alternatives unless they exit the specific substituent families and fluorine/linkage constraints. What methods claims does US 6,037,361 include, and how might they expand infringement? Answer: The patent includes methods of inhibiting specific MMPs (matrix metalloproteinase, gelatinase A, stromelysin-1, collagenase, matrilysin, MMP-13) and then expands to prevention/treatment of indications including atherosclerotic plaque rupture, aortic aneurysm, heart failure, restenosis, periodontal disease, corneal ulceration, burns, decubital ulcers, wound healing, and cancer, plus arthritis, autoimmune/inflammatory disorders, multiple sclerosis, inflammation and pain, and a list of neurodegenerative disorders (stroke, head trauma, spinal cord injury, Alzheimer’s, ALS, cerebral amyloid angiopathy, AIDS, Parkinson’s, Huntington’s, prion diseases, myasthenia gravis, Duchenne muscular dystrophy). How the methods are drafted Claims 10–15 are crisp: “method of inhibiting [MMP] comprising administering… a compound according to claim 1… in unit dosage form.” Claims 16–30 broaden the medical narrative but keep the legal hook as “administering” a compound according to claim 1 for prevention or treatment. Litigation risk pattern if a competitor sells an MMP inhibitor in this class If a marketed product uses a compound that falls under claim 1’s genus, then: Direct infringement exposure arises from clinical use and label/indication alignment with claims 16–30. Inducement/contributory exposure can arise even without identical disease language, because the methods claims are framed around administration to hosts suffering from listed conditions, but proof typically leans on evidence of use for those conditions. What is the composition-of-matter and formulation coverage in US 6,037,361? Answer: The patent includes pharmaceutical compositions as claim 31–32: a compound according to claim 1 in admixture with pharmaceutically acceptable excipient/diluent/carrier, with and without specifying “therapeutically effective amount.” Why this matters for generics and follow-on formulations Even if an applicant changes the formulation (tablet vs capsule, salt form vs free acid, excipient choice), the composition claims can still cover them if the active ingredient is within claim 1. The explicit mention of prodrugs and salts in claim 1 also makes it harder to avoid infringement by selecting alternative salt forms, unless the candidate active ingredient exits the claim 1 structure boundaries. How strong is the patent estate for this chemical series in the U.S.? Answer: Based on the claims alone, US 6,037,361 has high structural coverage (broad genus plus fluorine/linkage constraints) and broad use coverage (multiple MMPs and many indications). The estate’s strength relative to competitors will depend on whether later continuations, divisionals, or related patents exist in the same filing family that capture: additional substituent positions, different prodrug/salt forms, alternative crystalline forms, additional method-of-use refinements, and whether claims are supported by robust experimental data in the specification. This analysis cannot map the full family without the application/patent history, publication numbers, and other U.S. patents in the same priority chain. What generic entry risks exist for products that target MMPs using similar fluorinated dibenzofuran motifs? Answer: If a generic or follow-on applicant’s active ingredient is within claim 1, then generic launch is blocked at least by the composition and genus coverage, and may also be blocked by method-of-use risk depending on FDA labeling and actual use. Where design-arounds typically fail against this claim set Avoiding named examples in claim 7 is insufficient due to genus coverage. Escaping fluorine constraints is difficult because claim 1 expressly requires fluorine at defined positions (at least one of R³/R³a/R⁴/R⁴a and at least one of R⁷/R⁸). Changing Y to an unlisted linkage may work, but claim 1 includes multiple Y options and dependent claims still cover “Y = --O-- or --CH₂--” plus other substructures. Practical consequence for a challenger A developer would need to ensure the active ingredient structure falls outside: the dibenzofuran/dibenzothiophene linked scaffolding as defined by Formula I, the difluoro/hydroxyimino/oxo or related functional motif set, and the Y and fluorine provisos. What are the likely infringement “claim mapping” hotspots? Answer: The easiest-to-prove claim elements against accused products are the structural provisos and the functional group class. Hotspots within claim 1 Fluorine proviso: proving R³/R³a/R⁴/R⁴a includes a fluorine and R⁷/R⁸ includes a fluorine. Y linkage: proving the accused structure’s oxygen/sulfur motif matches one of the defined Y variants. Functional “acid/oxo/hydroxyimino/amido” region: proving the accused molecule includes the acid/oxo/hydroxyimino/thioxo/but-2-enoic equivalents that correspond to the claim’s Formula I and substituent options. R⁶ and aryl/heteroaryl side options: proving the correct allowed categories for R⁶, particularly the inclusion/exclusion of N-phthalimido and heteroaryl options. Key Takeaways US 6,037,361 is a broad genus patent for fluorinated dibenzofuran/dibenzothiophene-derived metalloproteinase inhibitors with defined fluorine constraints, plus prodrugs and salts. Enforcement leverage is two-tiered: claim 1 covers the chemical space, while claims 10–30 cover administration for inhibition of specific MMPs and for many matrix remodeling and inflammation-linked diseases. Named species in claim 7 materially assist claim construction and reduce ambiguity by providing concrete structures within the broader genus. Design-arounds face structural barriers because fluorine and linkage constraints are built into claim 1, not left purely optional. The true magnitude of the enforceable U.S. landscape depends on the family (continuations/divisionals) and the existence of other patents covering related salts, prodrugs, and follow-on formulations, which are not determinable from the claim text alone. FAQs 1) Does US 6,037,361 cover prodrugs and salts? Yes. Claim 1 expressly includes “pharmaceutically acceptable prodrug” and “pharmaceutically acceptable salt” of the Formula I compounds. 2) Which MMP targets are explicitly named in the methods claims? Matrix metalloproteinase (general) plus gelatinase A, stromelysin-1, collagenase, matrilysin, and MMP-13. 3) Are both compound and method of treatment claims present? Yes. The patent includes compound claims (genus/formula, plus specific species) and multiple method-of-use claims tied to MMP inhibition and disease treatment/prevention. 4) Do the dependent claims narrow “Y” to specific linkages? Yes. Claim 2 restricts Y to --O-- or --CH₂--. 5) What is the practical workaround most likely to fail against this patent? Changing only excipients or switching among salt forms of a compound that still falls within claim 1’s Formula I and fluorine/linkage constraints. References US Patent 6,037,361 (claims text provided in prompt). More… ↓ ⤷ Start Trial

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Smith & Nephew, Inc.	SANTYL	collagenase	Ointment	101995	June 04, 1965	6,037,361	2018-03-09
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Patent: 6,037,361

Summary for Patent: 6,037,361