United States Patent 11,793,806: Scope, Claims Construction, and US Patent Landscape for RBC Lifetime Extension in Pyruvate Kinase Deficiency (PKD)
US Patent 11,793,806 claims a therapeutic method-of-treatment for pyruvate kinase deficiency (PKD) by administering a compound of Formula (I), where the core scope is defined by a broad structural Markush-like framework (W/X/Y/Z, D/D1, A, L, R1 and substituent sets Ra/Rb/Rc/Rd, and ring/chain indices n, m, g, h) and anchored to functional outcome language: “increasing the lifetime of red blood cells (RBCs)”.
The patent’s risk profile is driven by two claim features that expand enforceable coverage beyond a single molecule: (1) large genus coverage over Formula (I) variants and (2) method framing tied to PKD and RBC lifetime, which can capture multiple candidate pyruvate kinase activators even when the exact species differs.
What does claim 1 of US Patent 11,793,806 cover for increasing RBC lifetime in PKD?
1) Claim 1 is a method-of-use genus claim
Claim 1 requires all of the following elements:
- Method: “increasing the lifetime of red blood cells (RBCs) in a subject”
- Population: “in a subject… in need thereof” and the subject “has pyruvate kinase deficiency (PKD)”
- Act: administering an “effective amount”
- Drug definition: administering a “compound of formula I or a pharmaceutically acceptable salt thereof”
Because the preamble is functional and tied to a disease state (PKD), enforceability typically hinges on proof of:
- a subject with PKD,
- RBC lifetime increase attributable to the administered compound, and
- that the administered compound is within the structural boundaries of Formula (I).
2) Formula (I) structure: broad Markush boundaries
Claim 1 defines Formula (I) using multiple variable positions:
- Ring atom selectors:
- W, X, Y, Z independently CH or N
- Link atom/bond selectors:
- D and D1 independently bond or NRb
- A substituent framework:
- A is optionally substituted aryl or heteroaryl
- Linker L options (key for SAR and literal scope):
- bond, —C(O)—, —(CRcRc)m—, —OC(O)—, —(CRcRc)m—OC(O)—, —(CRcRc)m—C(O)—, —NRbC(S)—, —NRbC(O)—
- with explicit attachment rule: “point of attachment to R1 is on the left-hand side”
- R1 core: alkyl, cycloalkyl, aryl, heteroaryl, heterocyclyl, substituted by 0–5 occurrences of Rd
- Substituent sets:
- R3: halo, haloalkyl, alkyl, hydroxyl, —ORa; or two adjacent R3 together form an optionally substituted heterocyclyl
- Ra: alkyl, acyl, hydroxyalkyl, haloalkyl
- Rb: hydrogen or alkyl
- Rc: hydrogen, halo, alkyl, alkoxy, haloalkoxy; or two adjacent Rc form an optionally substituted cycloalkyl
- Rd: broad substituent class including halogenated groups, nitro/cyano, hydroxyl, and multiple carbonyl/hetero-hetero substituents (—C(O)Ra, —OC(O)Ra, —C(O)ORa, —SRa, —NRaRb, —ORa) or two adjacent Rd form optionally substituted heterocyclyl
- Indices:
- n = 0, 1, or 2
- m = 1, 2, or 3
- h = 0, 1, 2
- g = 0, 1 or 2
Scope effect: the structural flexibility is substantial. Any “pyruvate kinase activator” candidate that maps onto the same scaffold and satisfies the defined substituent/heteroatom selectors can fall within claim 1 even if the compound is not the exact Example species.
3) Disease nexus and outcome language
The RBC-lifetime outcome is an element of the method claim. In litigation, that tends to require persuasive pharmacodynamic evidence (clinical or preclinical) that the administered Formula (I) compound increases RBC lifespan in PKD subjects. The patent’s value is therefore not only on chemistry coverage, but also on method demonstrability.
How do dependent claims 2–6 narrow the Formula (I) space in US 11,793,806?
Claim 2: A is a bicyclic heteroaryl
Claim 2 limits A from “optionally substituted aryl or heteroaryl” to optionally substituted bicyclic heteroaryl.
Impact: reduces coverage to specific bicyclic heteroaryl families while still leaving substantial variation in L, R1, and substituents.
Claim 3: numerical substituent indices fixed
Claim 3 sets:
This is a tightening of the substitution pattern.
Claims 4–6: specific heteroatom and D/D1 selections
- Claim 4: W, X, Y, Z are CH
- Claim 5: D is NRb and D1 is bond
- Claim 6: Rb is H, methyl, or ethyl
Scope effect: these claims narrow the variable heteroatom configuration at core aromatic positions and control whether a nitrogen-containing linkage (NRb) is present and what Rb substituents are allowed.
What do dependent claims 7–11 do to limit the linker L and ring length?
Claim 7: L limited to specific chemistry
Claim 7 restricts L to:
- bond, —(CRcRc)m—, —NRbC(O)—, —(CRcRc)m—C(O)—, —C(O)—, or —O(CO)—
Claim 8: L further narrowed
Claim 8 sets:
So the linker becomes a chain of substituted “CRcRc” units.
Claims 9–10: R1 restrictions
- Claim 9: R1 is cycloalkyl, aryl, heteroaryl, or heterocyclyl substituted with 0–5 Rd
- Claim 10: R1 is cycloalkyl
Claim 11: specific embodiment
Scope effect: these dependent claims describe a narrower “preferred embodiment” space. They function as fallbacks against close substitutes that might avoid claim 1 by linker changes, while still being caught by narrower sub-genus claims.
Which specific structural embodiments are claimed (claims 12–15)?
Claim 12: A is quinolinyl
Claim 12 limits A to quinolinyl.
Claim 13: another A definition (text truncated in prompt)
Claim 13 is present but the specific structure definition is incomplete in the provided claim text. Because the exact language is not fully available here, enforceable scope characterization cannot be completed beyond identifying it as an additional A-bounded variant.
Claim 15: fixed compound species for PKD RBC-lifetime increase
Claim 15 is a product-by-structure method claim and recites a specific compound:
N-(4-(4-(cyclopropylmethyl)piperazine-1-carbonyl)phenyl)quinoline-8-sulfonamide (or pharmaceutically acceptable salt), for increasing RBC lifetime in PKD subjects.
Scope effect: Claim 15 anchors a definable chemical entity within the method-of-treatment. Even if competitors attempt to design around the broad Formula (I) genus, Claim 15 can still provide direct coverage for this particular compound.
What is the practical scope for competitors under US 11,793,806?
1) Literal infringement drivers
A generic competitor or Roche/Sanofi-like licensee (depending on who holds rights to the active series) would need to map its candidate into Formula (I), including:
- heteroatom set W/X/Y/Z
- D and D1 configuration (bond vs NRb)
- A as aryl/heteroaryl or specifically bicyclic/quinolinyl per dependents
- linker L type (especially whether it can satisfy the limited options)
- R1 class and degree/identity of Rd substitutions
- index values (n, m, g, h, m)
- and whether the experimental compound still has the same structural topology required by the formula.
2) Design-around levers
From a freedom-to-operate perspective, the most direct design-around levers are typically:
- changing the linker L class (for example, moving outside the defined L set),
- changing the core heteroaryl “A” family such that it no longer fits quinolinyl/bicyclic restrictions (for dependent-claim fallbacks),
- changing substituent count or adjacency that controls g/h and the allowable substitution patterns,
- altering NRb presence (D/D1 settings) or changing the allowed Rb substituent class.
3) Method proof risk remains even for close chemical analogs
Even if a compound falls within Formula (I), method enforceability still depends on whether the accused label/clinical protocol effectively “increases RBC lifetime” in PKD subjects. But method claims in the pharmaceutical context are commonly asserted based on intended use and observed pharmacodynamic endpoints in the trial record for the compound.
How strong is the patent estate likely to be around RBC lifetime-in-PKD (structural genus + disease method)?
Claim architecture signals a “primary genus + layered species/fallbacks” pattern
- Claim 1: broad genus method with Formula (I)
- Claims 2–6: restrictions on aromatic heteroatom presence and D/D1 configuration and substitution counts
- Claims 7–11: linker and R1 narrowing to specific sub-scaffolds
- Claims 12–15: explicit A-substitution families and an explicit species with a fixed chemical name
This structure typically increases litigation staying power:
- even if a defendant argues invalidity or non-infringement against the broadest claim, narrower dependent claims can still remain in play.
What does the provided claim text imply about claim construction issues (US litigation lens)?
1) Markush interpretation
The numerous “independently selected from” and index ranges create interpretive questions about:
- whether particular embodiments fall cleanly within each variable slot,
- how adjacency constraints (“two adjacent Rc together…”) and “0–5 occurrences of Rd” operate with ring substitution.
2) Functional language “increasing RBC lifetime”
This creates a potential evidentiary battleground:
- whether the method is performed by administering the compound under conditions shown to increase RBC lifespan,
- and whether preclinical RBC survival studies or clinical reticulocyte/RBC turnover proxies are treated as sufficient.
3) “Subject has PKD”
If accused uses are in other pyruvate kinase-related contexts, the disease nexus element can be contested. But PKD-specific labeling and trial enrollment tend to support the prosecution history framing.
What other US patents typically surround this concept set (and how they may interact)?
The prompt provides only US 11,793,806 claim text, without the rest of the estate. Because a complete landscape requires publication lists, family members, and the Orange Book/Biologics/drug-device linkage, a full multi-patent mapping cannot be produced from the provided information alone.
What can be concluded from claim style and scope alone:
- US 11,793,806 is positioned as a method-of-use patent tied to a specific chemical scaffold class (Formula I) rather than merely formulation or manufacturing.
- In practice, the competitive freedom-to-operate for a specific pyruvate kinase activator series often hinges on whether there are co-pending or granted patents covering:
- the compound itself (composition of matter),
- additional polymorphs/salts,
- dosing regimens,
- and additional therapeutic endpoints in PKD.
Key Takeaways
- US 11,793,806 claim 1 is a method-of-treatment for PKD requiring administration of a Formula (I) compound to increase RBC lifespan.
- The patent’s chemical scope is broad due to extensive Markush variables (W/X/Y/Z, D/D1, A, L, R1 and Rd substitution, and indices n/m/g/h).
- Dependent claims narrow the scaffold through:
- fixing A to bicyclic heteroaryl and/or quinolinyl (claim 12),
- restricting W/X/Y/Z to CH (claim 4),
- requiring D = NRb and D1 = bond (claim 5) with constrained Rb (claim 6),
- limiting linker L to specific chemistry and then to —(CRcRc)m— and even —CH2— with n = 0 (claims 7–11),
- and locking in a specific species in claim 15: N-(4-(4-(cyclopropylmethyl)piperazine-1-carbonyl)phenyl)quinoline-8-sulfonamide for PKD RBC-lifetime increase.
- For competitors, the most actionable design-around surfaces are linker L class, core aromatic A family, and heteroatom/linkage choices (D/D1, W/X/Y/Z), while method-proof evidence ties the claim to PKD clinical/preclinical outcomes.
FAQs
1) What is the main claim element that ties US 11,793,806 to PKD?
Claim 1 requires the subject “has pyruvate kinase deficiency (PKD)” and the administration increases RBC lifetime.
2) Does US 11,793,806 protect a specific compound or a chemical class?
It protects a method using a Formula (I) class in claim 1 and also includes a specific species method in claim 15.
3) Which claim features most affect infringement risk for close chemical analogs?
The mapping of the accused compound into Formula (I) variables, especially A, L, and D/D1 selections, is decisive, with indices (n, m, g, h) further constraining dependent-claim coverage.
4) Can a compound outside the Formula (I) still infringe through dependent claims?
If it is outside claim 1’s Formula (I), it generally cannot satisfy dependent claims that further restrict claim 1 variables.
5) What is the strongest “anchoring” claim in the provided set?
Claim 15, which recites a named compound: N-(4-(4-(cyclopropylmethyl)piperazine-1-carbonyl)phenyl)quinoline-8-sulfonamide, for increasing RBC lifetime in PKD subjects.
