Details for Patent: 5,210,079

US Patent 5,210,079: Scope, Claims Structure, and US Patent Landscape for “AII-Mediated Chronic Renal Failure” Methods

What does US 5,210,079 claim, at the core?

US 5,210,079 claims methods of treating chronic renal failure mediated by AII (angiotensin II) in a mammal by administering a pharmaceutical composition defined by a very large Formula (I) chemical space, plus numerous conditional structural carve-outs (“provided that” limitations). The claims are method-of-treatment claims driven by a specific compound structural class and AII-mediated chronic renal failure indication.

At a practical level, claim coverage is determined by three layers:

1. Indication layer: “chronic renal failure mediated by AII in a mammal.”
2. Composition layer: administration of a “pharmaceutical composition” containing compounds of Formula (I).
3. Validity carve-outs: a long “provided that” clause that excludes subsets based on positional isomers (ortho/meta), substituent identity, and compatibility rules between groups (R1 vs X vs R13 vs R6 vs R7/R8, etc.).

The claims also narrow further via dependent claims to Formula (II) (a subset of Formula (I)) and then to named exemplified compounds.

How are the claims built (independent vs dependent scope)?

The submission you provided contains method claims numbered 1 through 31. Conceptually, the set breaks down into:

Independent claim foundation

• Claim 1: Method of treating chronic renal failure mediated by AII by administering a therapeutically effective amount of a composition having Formula (I), plus salt coverage, and extensive “provided that” restrictions.
• Claim 29 and claim 30: Additional repetitions/variations of the same overall claim theme (same treatment + Formula (I) with altered sub-parameter options and/or truncation of some definitions). These are effectively parallel independent claim formulations within the same patent.

Subset narrowing via dependent chain

• Claim 2: Narrows Claim 1’s Formula (I) to Formula (II).
• Claims 3-4: Additional parameter reductions inside Formula (II), including specific structural selections (e.g., definitions of R2, R6, R7, R8, etc., and constraints on X).
• Claims 5-28: Each depends on Claim 4 and enumerates specific Formula (II) compounds by name (multiple distinct imidazole/tetrazole/biphenyl-carboxylic acid or aldehyde patterns, plus variants such as tetrazole vs non-tetrazole and trifluoromethyl vs other substituents).
• Claim 31: Another independent-like method repetition with a shorter/modified Formula (I) definition and a condensed “provided that” section.

Coverage outcome

• Broadest legal scope is Claim 1 / Claim 29 / Claim 31: they cover all Formula (I) compounds that meet the AII-mediated chronic renal failure method and do not fall into the “provided that” exclusions.
• Meaningful narrowing occurs through the Formula (II) subset (Claim 2) plus the additional R-parameter constraints (Claims 3-4).
• Highest enforceability often comes from the named compound claims (Claims 5-28) because they reduce chemical discretion and map to specific targets.

What is the key technical mechanism in claim language (and how it limits competitors)?

The method premise is explicit: “chronic renal failure mediated by AII”. That ties method coverage to an AII-pathway framing, which functionally limits enforcement to therapeutic contexts where the claimed regimen is for AII-mediated disease progression rather than nonspecific renal failure.

Competitor design-around paths are therefore:

• Use of different biological targets (not AII-mediated) in the claimed therapeutic rationale (a legal strategy but not automatically dispositive).
• Use of compounds outside Formula (I) or outside Formula (II).
• Use of Formula (I)/(II) compounds that violate one of the “provided that” exclusion rules.

How broad is the chemical scope (Formula (I))?

Formula (I) is not a single structure. It is a template with dozens of substitutable parameters:

• Aromatic/hetero substituent families at multiple positions: halogens (Cl/Br/I/F), nitro, cyano, aryl/furyl.
• Extensive “R” options including:
  • Various alkyl lengths (commonly 1 to 4 carbon atoms, and elsewhere up to 1 to 10 or 3 to 10).
  • Multiple functional groups (CO2H, alkoxy, acyloxy, NHSO2CH3, NHSO2CF3, CONHR12, SO2NH2, etc.).
  • Linkage variety at X (single bond, CO, CH2, O, S, NH, OCH2, CH2O, SCH2, CH2S, NHC(R27)(R28), sulfonamides, sulfonyl linkages, unsaturated linkers, perfluorinated linkers, etc.).
  • Variable heterocycle substitution at Y, Z (O or S; Z is O/NR11/S).
  • Variable ring lengths and spacer counts: m (1-5), n (1-10), p (0-3), q (2-3), r (0-2), s (0-5), t (0-1).
• Explicit inclusion of “pharmaceutically acceptable salt(s)”.

In short, the claim is a large Markush-style envelope.

Where do the claims get tightest? (the “provided that” exclusions)

Claim 1 contains a detailed set of exclusions that operate like a negative filter across the Markush space. The “provided that” section includes, among other conditions:

Positional-isomer exclusions and compatibility rules

Key examples from Claim 1 include:

1. R1 not ortho.
2. If R1 is a substituted group (shown in the claim as a particular aryl/hetero substitution pattern) and X is a single bond, then R13 must be ortho or meta; specific sulfonamide identities force ortho (e.g., NHSO2CF3 / NHSO2CH3 conditions).
3. If R1 is a specific group and X is other than a single bond, then R13 must be ortho, with exceptions where R13 is NHSO2CF3 or NHSO2CH3 allowing ortho or meta depending on the X sub-type.

Substituent identity exclusions

More discrete carve-outs include:

4. If R1 is 4-CO2H (or salt), then R6 cannot be S-alkyl.
5. If R1 is 4-CO2H (or salt), then the imidazole 4-position substituent cannot be CH2OH, CH2OCOCH3, or CH2CO2H.
6. When a specified R1/X/R13 combination holds, R6 cannot be certain alkyl-thio patterns (e.g., constraints tied to C2H5S in the claim text).
7. If R1 and R6 meet certain definitions (e.g., R6 = n-hexyl), then R7 and R8 cannot both be hydrogen.
8. If R1 corresponds to a specific shown group, then R6 is not methoxybenzyl.
9. If R6 is in a certain methoxybenzyl-like restriction or if R6 contains specific substituted moieties, additional disallowances apply (e.g., “not CHFCH2CH2CH3 or CH2OH” style exclusions).
10. Several conditional exclusions tie r values (0/1/O) to restrictions on R13 identity and R6 identity and then restrict R7/R8.

Enforceability implication

These exclusions are where competitors have the best surface area for designing around:

• Alter the orientation of R1 and R13 on the aromatic system (ortho/meta logic).
• Alter the X linkage type to trigger a different R13 positional requirement.
• Change the imidazole substituent at the position constrained by R1 = 4-CO2H rules.
• Avoid specific “R7 and R8 both H” combinations when R6 is fixed as n-hexyl in the relevant R1 context.

What does Claim 2 (Formula II) narrow?

Claim 2 narrows Formula (I) into Formula (II) and adjusts R1/R6/R8/R13/R16/X.

In Claim 2, the formula II parameter selection includes:

• R1 limited to: --CO2H, --NHSO2CF3, and a larger substituent pattern (shown in the claim).
• R6 becomes: alkyl/alkenyl/alkynyl 3-10 carbons, or cycloalkyl 3-8, or benzyl with up to two specified substituents (alkoxy/halogen/alkyl/nitro).
• R8 limited to a phenylalkenyl alkenyl portion length 2 to 4 carbons, or imidazole/triazolyl methylene-linked heterocycles.
• R13 reduced to a smaller set: --CO2H, --CO2R9, NHSO2CF3, SO3H, and another shown arylphosphoric acid-like class in the claim text.
• X limited to a smaller set than Claim 1: single bond, CO linkage, CH2CH2 linkage, O, S, NHCH2, CH2NH, CH=CH-type linkers.

This makes Formula II a narrower chemical “slice” suitable for focusing prosecution and for mapping to marketed compound candidates.

What do Claims 5-28 do (named compound anchors)?

Claims 5 through 28 depend from Claim 4 and each names a specific compound, typically defined by:

• A chiral/alkenyl substitution at “2-” or “2-(1E-Butenyl)” style positions.
• A 4-chloro imidazole feature.
• A biphenyl-4-ylmethyl linkage.
• A second ring containing either:
  • tetrazol-5-yl substituent on the biphenyl, or
  • carboxy substituent on the biphenyl.
• A terminal group on the imidazole of either:
  • hydroxymethyl, carboxaldehyde, or carboxylic acid, and sometimes
  • protected equivalents via (methoxycarbonyl)aminomethyl or (propoxycarbonyl)aminomethyl.

This claim block creates a strong “hit list” of specific compounds within the broad Markush envelope.

Named compounds included (subset mapping)

The following claim examples are explicitly listed in your text:

• 2-Butyl-4-chloro-1-[(2'-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]-5-(hydroxymethyl)imidazole (Claim 5)
• …-5-(carboxaldehyde) (Claim 9)
• 2-Butyl-4-chloro-1-[(2'-carboxybiphenyl-4-yl)methyl]-5-(hydroxymethyl)imidazole (Claim 6)
• …-5-[(methoxycarbonyl)aminomethyl]imidazole (Claim 7)
• …-5-[(propoxycarbonyl)aminomethyl]imidazole (Claim 8)
• 2-Propyl-4-chloro-1-[(2'-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]-5-(hydroxymethyl)imidazole (Claim 13)
• …-5-(carboxaldehyde) (Claim 14)
• 2-Butyl-4-chloro-1-[(2'-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]imidazole-5-carboxylic acid (Claim 18)
• 2-Propyl-4-trifluoromethyl-1-[(2'-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]imidazole-5-carboxylic acid (Claim 20)
• …-5-(hydroxymethyl)imidazole (Claim 21)
• 2-Propyl-4-pentafluoroethyl-1-[(2'-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]imidazole-5-(hydroxymethyl)imidazole (Claim 24)
• Multiple additional named imidazole aldehyde and carboxylic acid variants, plus 1-(biphenylmethyl)-4-phenyl-2-propyl imidazole examples (Claims 27-28), and other alkenyl (1E-butenyl) analogs (Claims 11-12, 16-17).

Practical landscape impact

Named exemplars often become the nucleus for:

• enforcement against exact formulations,
• freedom-to-operate mapping for specific candidate compounds,
• and argument focus in litigation where exact match to exemplified structures matters more than broad Markush interpretation.

What is the likely competitive landscape shape (based on claim scope logic)?

With no prosecution history, expiration dates, or family member filings in your provided text, the only defensible landscape analysis comes from scope architecture:

• The patent covers a chemically broad but structurally constrained AII-mediated CKD treatment method.
• Competitors with high similarity in imidazole/biphenyl/tetrazole-carboxylate motifs risk falling within Formula (I)/(II).
• Competitors seeking safe designs typically change at least one major axis:
  1. Core pharmacophore: avoid the imidazole pattern and related linkage framework.
  2. AII-medicated method posture: position use claims to different etiologies or different pathway mediation.
  3. Aromatic substitution patterns: alter ortho/meta positioning and avoid the specified “provided that” combinations.
  4. X linkage category: swap the linkage class that triggers positional constraints on R13.

Key “scope vs claims” conclusions for FTO and IP strategy

Coverage is method-based, but compound-defined

• The method claim is broad in indication language (“chronic renal failure mediated by AII”).
• The compound definition is broad in Markush options but narrowed by multiple exclusion conditions.

The “provided that” clause is not decorative

Those exclusions:

• restrict positional isomer placement,
• restrict R6 identity when R1 = 4-CO2H,
• restrict imidazole 4-position substituents,
• and impose compatibility logic among groups (R1 vs X vs R13 vs R6 vs R7/R8).

Formula II and named exemplars reduce ambiguity

• Formula II compresses the chemical options.
• Claims 5-28 list concrete compounds. That matters if a product matches or nearly matches those structures.

Key Takeaways

• US 5,210,079 covers AII-mediated chronic renal failure treatment methods using a therapeutically effective amount of compounds defined by Formula (I), with pharmaceutically acceptable salts included.
• Claim scope is Markush-broad but structurally gated by a lengthy “provided that” exclusion set that tightly constrains positional relationships (ortho/meta), linkage type (X), and substituent compatibility (notably involving R1, R6, R7, R8, R13).
• Dependent narrowing to Formula (II) substantially reduces allowable structures and is followed by multiple named exemplars (Claims 5-28) anchored in specific imidazole/biphenyl/tetrazolyl or carboxy-biphenyl motifs.
• Design-around is most plausible by changing at least one major structural axis that controls Formula (I)/(II) inclusion, or by stepping outside the constrained ortho/meta and compatibility rules embedded in the “provided that” clause.

FAQs

1. Which claim is the broadest in chemical scope?
   Claim 1 (and parallel scope formulations in Claims 29 and 31) is the broadest because it defines compounds by Formula (I) with the largest parameter sets, subject to the “provided that” exclusions.

2. What does the “provided that” clause do for infringement risk?
   It acts as an explicit exclusion filter: even if a compound fits Formula (I), it may fall outside the claim if it violates positional or group-compatibility restrictions.

3. Why is Claim 2 strategically important?
   Claim 2 narrows Formula (I) into Formula (II) with reduced parameter options and a smaller X/linkage set, making it easier to map candidate compounds into or out of coverage.

4. Do Claims 5-28 matter more than the broad Markush claim?
   They often matter for enforceability and mapping because they are named specific compounds, reducing interpretive ambiguity versus purely parameterized Markush coverage.

5. Does the patent cover salts and formulations?
   Yes. The claims explicitly include “pharmaceutically acceptable salt” coverage for the defined compounds and claim the administration of a pharmaceutical composition containing those compounds.

References

[1] US Patent 5,210,079.