United States Patent 10,280,414: Critical Claims Assessment and US Landscape

US Patent 10,280,414 claims multimeric forms of human alpha-galactosidase A (Agalsidase alpha/beta) created by covalently cross-linking at least two enzyme monomers through a non-native linking moiety (often specified as poly(alkylene glycol), including PEG), coupled with performance screens in plasma, lysosomal conditions, and improved in vivo-like circulation half-life. The patent’s enforceable scope is driven by (1) the structural requirement (covalent multimer via a defined linking moiety), (2) the biochemical/functional requirement (alpha-galactosidase activity retention or improvement under multiple stress conditions vs native enzyme), and (3) a pharmacokinetic delta (circulating half-life up by at least 20% vs native). The strongest claim axes are the non-native linking moiety constraint (claim 3) and the performance thresholds tied to plasma and lysosomal stability plus half-life (claim 1), while the weakest axes are breadth (dimer to potentially higher multimers) paired with highly specific experimental definitions and performance cutoffs that can be difficult to reproduce exactly across assays, matrices, and time windows.

What is claimed, in enforceable terms?

Claim 1: Multimeric alpha-galactosidase A with plasma and lysosomal performance plus half-life uplift

Claim 1 requires all of the following:

Structure

“At least two” alpha-galactosidase A monomers
Covalently linked “via a linking moiety”
Multimeric structure has a “characteristic selected from” a nine-part performance set.

Functional screen (one of (a) to (i) must be met)

Plasma, 1 hour: activity is ≥10% higher than native (a), or decreases less than native by ≥10% (b), or remains substantially unchanged (c).
Lysosomal conditions, 1 week: activity ≥10% higher (d).
Lysosome, 1 day: decreases less than native by ≥10% (e), or remains substantially unchanged (f).
Immediate lysosomal conditions: activity ≥10% higher than native (g).
Immediate neutral aqueous conditions (pH 7, 37°C): activity ≥10% higher than native (h).
Circulation half-life: ≥20% higher than native (i).

Key enforceability point

Claim 1 is “optionally characterized”: it does not require all nine performance behaviors, only one that falls within the selected characteristic set. That makes infringement easier to plead if a competitor can be mapped to any one of the enumerated performance modalities.

Claims 2 and 4: Cross-linking process

Claim 2: reacting alpha-galactosidase A with a cross-linking agent that includes the linking moiety and “at least two reactive groups.”
Claim 4: identical process concept but tethered to claim 3’s “linking moiety not present in native alpha-galactosidase A.”

Enforcement reality

Process claims will be difficult for a competitor if the final product can be purchased but the competitor’s manufacturing steps are not revealed. But if a competitor’s process uses an identical cross-linking approach, these become a potent complement.

Claims 3 and 5: Definition by “non-native” linking moiety and a dimer example

Claim 3: multimer has a linking moiety “not present in native alpha-galactosidase A.”
Claim 5: dimeric protein structure with exactly two alpha-galactosidase monomers covalently linked via a linking moiety comprising poly(alkylene glycol).

Critical constraint

Claim 5 narrows claim 1’s broad “at least two” to a dimer with a poly(alkylene glycol) (PAG) linking moiety.

Claims 6–10: PEG-specific and bond-chemistry constraints

Claim 6: PAG has at least two functional groups; each forms a covalent bond with one monomer.
Claim 7: functional groups are terminal groups of the PAG chain.
Claim 8: at least one functional group forms an amide bond with an enzyme monomer.
Claim 9: PAG has at least 5 alkylene glycol units.
Claim 10: PAG is polyethylene glycol (PEG).

These claims are chemistry-tight. They are well-suited to capture competitors using PEG cross-linkers that produce terminally attached, covalent PEG bridges with at least one amide linkage.

Claims 11–15: Performance characterization tied to claim 5 multimer

Claim 11 repeats the performance set for the specific dimeric PEG-linked structure, with one notable difference:

It includes alternative plasma/lysosome “range” language (50% to 150% of initial activity) in addition to ≥10% delta formats.

Claim 12–15 broaden alpha-galactosidase source/sequence options

Claim 12: enzyme is human alpha-galactosidase selected from agalsidase alpha and agalsidase beta.
Claim 13: plant recombinant alpha-galactosidase.
Claim 14: enzyme has ≥95% sequence identity to SEQ ID NO: 15.
Claim 15: enzyme sequence is one of SEQ ID NO:1, 2, 3, or 15.

These widen the underlying enzyme identity beyond only commercial Fabry ERTs, which matters because PEG cross-linking strategies can be applied to recombinant variants.

Claims 16–18: Formulation and Fabry treatment method

Claim 16: pharmaceutical composition with multimer and carrier.
Claim 17: treating Fabry disease with therapeutically effective dose of the multimer.
Claim 18: administration by intravenous infusion.

Claims 19–20: Further process details

Claim 19: reacting alpha-galactosidase A with a cross-linking agent including linking moiety and at least two reactive groups.
Claim 20: reactive groups comprise a leaving group.

This is consistent with typical PEG bifunctional linker chemistries (e.g., activated esters or halides) but is not specific enough to uniquely identify a single commercial linkage system.

How tight are the novelty-defining concepts?

1) Multimeric covalent PEG-linked enzyme for Fabry

The core innovation is not “PEGylation” in general. It is covalent multimerization (dimer) of alpha-galactosidase A using a linking moiety not present in native enzyme, with PAG/PEG being a specified linkage architecture.

Many prior approaches in Fabry therapeutics focus on:

enzyme replacement itself (agalsidase alpha/beta),
PEGylated monomeric forms,
antibody or receptor targeting,
or encapsulation strategies.

The claim distinguishes itself by requiring covalent linkage between monomers rather than adsorption or reversible PEG shielding. That shifts the novelty toward stable, product-defining structural chemistry.

2) Performance claim language: “selected from” a multi-modal screen

Claim 1’s nine-item performance list makes the patent less dependent on a single assay design. If a competitor’s multimer shows improved plasma stability (a), reduced degradation (b/e), immediate retention (g/h), or improved half-life (i), it can still land within the claim.

However, the thresholds are still specific:

at least 10% delta for multiple categories,
and 20% for circulating half-life.

That creates an evidentiary burden for enforcement. If the competitor’s performance is measured under different matrices or time points, they may argue the claim-defined characteristic is not met.

3) Non-native linking moiety constraint

Claim 3’s “linking moiety is not present in native alpha-galactosidase A” is broad, but effective because the multimer is defined by a covalent linkage that inherently does not exist in native purified enzyme. This is a standard claim anchor for linking-molecule inventions.

Where the claim scope is broad (and where it narrows)

Broad scope

Claim 1 covers at least two monomers (could include trimers or higher multimers).
Claim 1 does not mandate PEG; PEG is only explicit from claim 5 onward.
Claim 11 includes variants in performance characterization (delta or range language).
Claims 12–15 allow broad enzyme identity and sequence latitude.

Narrow scope

The strongest “structure-defined” coverage sits in claims 5–10:
- dimeric structure,
- poly(alkylene glycol), specifically PEG,
- at least 5 units,
- terminal functional groups,
- at least one amide bond with an enzyme monomer.
If a competitor uses a different linker type (e.g., non-PAG chemistries, non-amide bond, non-terminal attachment) the dimer claims may fall away, leaving only broader claim 1 (but claim 1 still requires a linking moiety and performance characteristics).

Patent landscape analysis for this concept (US): what matters for freedom-to-operate

Without the full bibliographic record for US 10,280,414 (publication family members, priority claims, and prosecution history), a reliable landscape must be constrained to the claim-level innovation axes. Based on those axes, the practical US landscape for a PEG-linked covalent multimer of alpha-galactosidase A will cluster around:

A) Covalent enzyme multimerization / cross-linking

Competitors typically seek:

higher stability in plasma,
lysosomal trafficking resilience,
reduced immunogenicity through altered clearance and aggregation profiles,
and extended half-life via size/structure or altered degradation.

Covalent cross-linking between enzyme monomers is a distinct chemical design space with potential overlap in prior art on:

cross-linked proteins,
enzyme dimers/oligomers,
PEG-based cross-linkers and enzyme stabilization.

B) PEG chemistry for protein stabilization

This includes:

monomeric PEGylated alpha-galactosidase,
PEG conjugates that do not cross-link two protein monomers covalently,
and PEG linkers used to generate stable protein-protein constructs.

Claim 5–10 will be most directly relevant to any competitor using PEG as a covalent bridge between two alpha-galactosidase monomers.

C) Assay-defined performance categories

Even where structural overlap exists, enforcement and validity are sensitive to:

plasma vs lysosomal conditioning time windows (1 hour vs 1 day vs 1 week),
pH/temperature “immediate” testing (pH 7, 37°C),
half-life model (human plasma vs “physiological system” in claim 1(i) and claim 11),
percent-of-native vs percent-of-initial comparisons.

A competitor can often change assay conditions or reporting metrics to reduce the chance of meeting the claim’s exact “selected characteristic” thresholds.

Claim strength and attack surfaces (validity and infringement)

1) Infringement pathway

For a competitor’s product to infringe claim 5:

it must be a dimer of alpha-galactosidase A linked by PEG/PAG with terminal functional groups,
and include at least one amide bond to an enzyme monomer,
and satisfy one of claim 11’s performance characteristics.

A direct infringement case is strongest when internal data on:

stability in plasma and lysosomal mimetics,
and half-life in relevant models is consistent with the claim thresholds.

2) Validity risk areas

Key attack vectors typically include:

Prior art overlap on covalent PEG cross-linking of proteins
If prior documents show covalent PEG bridging between enzyme monomers with stability and half-life improvements, claim 5–10 face novelty challenges.
Obviousness driven by known linkage chemistry
If cross-linking activated PEG reagents with terminal groups and amide bond formation on proteins is routine, an examiner may consider applying this to alpha-galactosidase A an obvious variant absent a clear unexpected result.
Indefiniteness / enablement if the assay definitions are non-standard
Claim 1 and 11 anchor activity to “human plasma conditions for one hour” and “lysosomal conditions,” but the claims do not specify buffers, enzyme-to-condition ratios, or the definition of “substantially unchanged.” In some jurisdictions, these gaps can create enablement or definiteness disputes.
Written description mismatch if sequence variants are broad
Claims 12–15 permit varied source/identity/sequence while the structural linkage remains focused. If the specification support is enzyme-sequence general, that helps the patent. If not, it creates vulnerability.

3) Design-around options

Competitors can design around by:

using a non-PAG linker (breaking claim 5–10),
using PAG but with non-terminal functional groups or non-amide linkages (breaking claim 6–8),
producing non-dimer multimers (depending on interpretation of claim 5 as a fixed dimer),
achieving performance improvements but not crossing the stated deltas (avoiding the ≥10% or ≥20% thresholds in claim 1/11).

Practical relevance to Fabry ERT economics and product differentiation

If a PEG-linked covalent multimer demonstrably:

holds enzyme activity in plasma and lysosomal conditions,
and extends circulating half-life by ≥20%,

it supports two commercial levers:

less frequent dosing (if half-life translates in vivo),
and improved efficacy through more stable delivery and reduced loss.

But the claim format also implies a regulatory and manufacturing burden: the product must remain within a defined performance window. That creates CMC risk because stability and half-life are sensitive to:

PEG chain length distribution,
degree of cross-linking,
monomer integrity and aggregation profile.

Key Takeaways

US 10,280,414 centers on covalent multimerization of alpha-galactosidase A monomers via a non-native linking moiety, with PEG-based dimer embodiments (claims 5–10) as the most structurally enforceable core.
Claim 1 and claim 11 rely on assay-linked performance thresholds (≥10% in plasma/lysosome conditions for specified windows and ≥20% half-life improvement) under a “selected characteristic” framework, making infringement possible through multiple alternative performance routes.
The strongest enforceable narrowing occurs in claims 5–10 (PEG/PAG dimer, terminal groups, at least 5 units, at least one amide bond). Deviations in linker chemistry or bond formation are the most direct design-around levers.
The most likely validity pressure points are overlap with prior art on covalent PEG cross-linking of proteins and the risk that performance thresholds depend on assay conditions not fully specified in the claim language.

FAQs

What is the single most important structural requirement in US 10,280,414?
Covalently linking at least two alpha-galactosidase A monomers via a linking moiety that is not present in native alpha-galactosidase A (claims 1 and 3).
Which claims most tightly define the chemical linker?
Claims 5–10: PEG/PAG as the linking moiety, dimeric structure, terminal functional groups, PEG chain length at least 5 units, and at least one amide bond.
Does claim 1 require plasma and lysosome stability simultaneously?
No. Claim 1 requires the multimer to have at least one “characteristic” selected from the listed plasma/lysosome/half-life performance options.
What performance metrics drive patent coverage?
Activity deltas under “human plasma conditions” (1 hour), “lysosomal conditions” (immediate, 1 day, and 1 week), and a circulation half-life increase (≥20%) relative to native alpha-galactosidase A.
What is the most direct way to avoid claims 5–10?
Use a linkage mechanism that is not PEG/PAG terminally functionalized with an amide-forming bond, or avoid forming the specific PEG-bridged dimer architecture.

References (APA)

United States Patent 10,280,414 (claims provided).

Title:	Stabilized .alpha.-galactosidase and uses thereof
Abstract:	Multimeric protein structures comprising at least two alpha-galactosidase monomers being covalently linked to one another via a linking moiety are disclosed herein, as well a process for preparing same, and methods of treating Fabry disease via administration of a multimeric protein structure. The disclosed multimeric protein structures exhibit an improved performance, in terms of enhanced activity and/or a longer lasting activity under both lysosomal conditions and in a serum environment.
Inventor(s):	Shulman; Avidor (Rakefet, IL), Ruderfer; Ilya (Carmiel, IL), Ben-Moshe; Tehila (Koranit, IL), Shekhter; Talia (Petach-Tikva, IL), Azulay; Yaniv (Akko, IL), Kizhner; Tali (Atzmon-Segev, IL), Shaaltiel; Yoseph (Timrat, IL)
Assignee:	Protalix Ltd. (Carmiel, IL)
Application Number:	15/636,753
Patent Claims:	see list of patent claims
Patent landscape, scope, and claims summary:	United States Patent 10,280,414: Critical Claims Assessment and US Landscape US Patent 10,280,414 claims multimeric forms of human alpha-galactosidase A (Agalsidase alpha/beta) created by covalently cross-linking at least two enzyme monomers through a non-native linking moiety (often specified as poly(alkylene glycol), including PEG), coupled with performance screens in plasma, lysosomal conditions, and improved in vivo-like circulation half-life. The patent’s enforceable scope is driven by (1) the structural requirement (covalent multimer via a defined linking moiety), (2) the biochemical/functional requirement (alpha-galactosidase activity retention or improvement under multiple stress conditions vs native enzyme), and (3) a pharmacokinetic delta (circulating half-life up by at least 20% vs native). The strongest claim axes are the non-native linking moiety constraint (claim 3) and the performance thresholds tied to plasma and lysosomal stability plus half-life (claim 1), while the weakest axes are breadth (dimer to potentially higher multimers) paired with highly specific experimental definitions and performance cutoffs that can be difficult to reproduce exactly across assays, matrices, and time windows. What is claimed, in enforceable terms? Claim 1: Multimeric alpha-galactosidase A with plasma and lysosomal performance plus half-life uplift Claim 1 requires all of the following: Structure “At least two” alpha-galactosidase A monomers Covalently linked “via a linking moiety” Multimeric structure has a “characteristic selected from” a nine-part performance set. Functional screen (one of (a) to (i) must be met) Plasma, 1 hour: activity is ≥10% higher than native (a), or decreases less than native by ≥10% (b), or remains substantially unchanged (c). Lysosomal conditions, 1 week: activity ≥10% higher (d). Lysosome, 1 day: decreases less than native by ≥10% (e), or remains substantially unchanged (f). Immediate lysosomal conditions: activity ≥10% higher than native (g). Immediate neutral aqueous conditions (pH 7, 37°C): activity ≥10% higher than native (h). Circulation half-life: ≥20% higher than native (i). Key enforceability point Claim 1 is “optionally characterized”: it does not require all nine performance behaviors, only one that falls within the selected characteristic set. That makes infringement easier to plead if a competitor can be mapped to any one of the enumerated performance modalities. Claims 2 and 4: Cross-linking process Claim 2: reacting alpha-galactosidase A with a cross-linking agent that includes the linking moiety and “at least two reactive groups.” Claim 4: identical process concept but tethered to claim 3’s “linking moiety not present in native alpha-galactosidase A.” Enforcement reality Process claims will be difficult for a competitor if the final product can be purchased but the competitor’s manufacturing steps are not revealed. But if a competitor’s process uses an identical cross-linking approach, these become a potent complement. Claims 3 and 5: Definition by “non-native” linking moiety and a dimer example Claim 3: multimer has a linking moiety “not present in native alpha-galactosidase A.” Claim 5: dimeric protein structure with exactly two alpha-galactosidase monomers covalently linked via a linking moiety comprising poly(alkylene glycol). Critical constraint Claim 5 narrows claim 1’s broad “at least two” to a dimer with a poly(alkylene glycol) (PAG) linking moiety. Claims 6–10: PEG-specific and bond-chemistry constraints Claim 6: PAG has at least two functional groups; each forms a covalent bond with one monomer. Claim 7: functional groups are terminal groups of the PAG chain. Claim 8: at least one functional group forms an amide bond with an enzyme monomer. Claim 9: PAG has at least 5 alkylene glycol units. Claim 10: PAG is polyethylene glycol (PEG). These claims are chemistry-tight. They are well-suited to capture competitors using PEG cross-linkers that produce terminally attached, covalent PEG bridges with at least one amide linkage. Claims 11–15: Performance characterization tied to claim 5 multimer Claim 11 repeats the performance set for the specific dimeric PEG-linked structure, with one notable difference: It includes alternative plasma/lysosome “range” language (50% to 150% of initial activity) in addition to ≥10% delta formats. Claim 12–15 broaden alpha-galactosidase source/sequence options Claim 12: enzyme is human alpha-galactosidase selected from agalsidase alpha and agalsidase beta. Claim 13: plant recombinant alpha-galactosidase. Claim 14: enzyme has ≥95% sequence identity to SEQ ID NO: 15. Claim 15: enzyme sequence is one of SEQ ID NO:1, 2, 3, or 15. These widen the underlying enzyme identity beyond only commercial Fabry ERTs, which matters because PEG cross-linking strategies can be applied to recombinant variants. Claims 16–18: Formulation and Fabry treatment method Claim 16: pharmaceutical composition with multimer and carrier. Claim 17: treating Fabry disease with therapeutically effective dose of the multimer. Claim 18: administration by intravenous infusion. Claims 19–20: Further process details Claim 19: reacting alpha-galactosidase A with a cross-linking agent including linking moiety and at least two reactive groups. Claim 20: reactive groups comprise a leaving group. This is consistent with typical PEG bifunctional linker chemistries (e.g., activated esters or halides) but is not specific enough to uniquely identify a single commercial linkage system. How tight are the novelty-defining concepts? 1) Multimeric covalent PEG-linked enzyme for Fabry The core innovation is not “PEGylation” in general. It is covalent multimerization (dimer) of alpha-galactosidase A using a linking moiety not present in native enzyme, with PAG/PEG being a specified linkage architecture. Many prior approaches in Fabry therapeutics focus on: enzyme replacement itself (agalsidase alpha/beta), PEGylated monomeric forms, antibody or receptor targeting, or encapsulation strategies. The claim distinguishes itself by requiring covalent linkage between monomers rather than adsorption or reversible PEG shielding. That shifts the novelty toward stable, product-defining structural chemistry. 2) Performance claim language: “selected from” a multi-modal screen Claim 1’s nine-item performance list makes the patent less dependent on a single assay design. If a competitor’s multimer shows improved plasma stability (a), reduced degradation (b/e), immediate retention (g/h), or improved half-life (i), it can still land within the claim. However, the thresholds are still specific: at least 10% delta for multiple categories, and 20% for circulating half-life. That creates an evidentiary burden for enforcement. If the competitor’s performance is measured under different matrices or time points, they may argue the claim-defined characteristic is not met. 3) Non-native linking moiety constraint Claim 3’s “linking moiety is not present in native alpha-galactosidase A” is broad, but effective because the multimer is defined by a covalent linkage that inherently does not exist in native purified enzyme. This is a standard claim anchor for linking-molecule inventions. Where the claim scope is broad (and where it narrows) Broad scope Claim 1 covers at least two monomers (could include trimers or higher multimers). Claim 1 does not mandate PEG; PEG is only explicit from claim 5 onward. Claim 11 includes variants in performance characterization (delta or range language). Claims 12–15 allow broad enzyme identity and sequence latitude. Narrow scope The strongest “structure-defined” coverage sits in claims 5–10: dimeric structure, poly(alkylene glycol), specifically PEG, at least 5 units, terminal functional groups, at least one amide bond with an enzyme monomer. If a competitor uses a different linker type (e.g., non-PAG chemistries, non-amide bond, non-terminal attachment) the dimer claims may fall away, leaving only broader claim 1 (but claim 1 still requires a linking moiety and performance characteristics). Patent landscape analysis for this concept (US): what matters for freedom-to-operate Without the full bibliographic record for US 10,280,414 (publication family members, priority claims, and prosecution history), a reliable landscape must be constrained to the claim-level innovation axes. Based on those axes, the practical US landscape for a PEG-linked covalent multimer of alpha-galactosidase A will cluster around: A) Covalent enzyme multimerization / cross-linking Competitors typically seek: higher stability in plasma, lysosomal trafficking resilience, reduced immunogenicity through altered clearance and aggregation profiles, and extended half-life via size/structure or altered degradation. Covalent cross-linking between enzyme monomers is a distinct chemical design space with potential overlap in prior art on: cross-linked proteins, enzyme dimers/oligomers, PEG-based cross-linkers and enzyme stabilization. B) PEG chemistry for protein stabilization This includes: monomeric PEGylated alpha-galactosidase, PEG conjugates that do not cross-link two protein monomers covalently, and PEG linkers used to generate stable protein-protein constructs. Claim 5–10 will be most directly relevant to any competitor using PEG as a covalent bridge between two alpha-galactosidase monomers. C) Assay-defined performance categories Even where structural overlap exists, enforcement and validity are sensitive to: plasma vs lysosomal conditioning time windows (1 hour vs 1 day vs 1 week), pH/temperature “immediate” testing (pH 7, 37°C), half-life model (human plasma vs “physiological system” in claim 1(i) and claim 11), percent-of-native vs percent-of-initial comparisons. A competitor can often change assay conditions or reporting metrics to reduce the chance of meeting the claim’s exact “selected characteristic” thresholds. Claim strength and attack surfaces (validity and infringement) 1) Infringement pathway For a competitor’s product to infringe claim 5: it must be a dimer of alpha-galactosidase A linked by PEG/PAG with terminal functional groups, and include at least one amide bond to an enzyme monomer, and satisfy one of claim 11’s performance characteristics. A direct infringement case is strongest when internal data on: stability in plasma and lysosomal mimetics, and half-life in relevant models is consistent with the claim thresholds. 2) Validity risk areas Key attack vectors typically include: Prior art overlap on covalent PEG cross-linking of proteins If prior documents show covalent PEG bridging between enzyme monomers with stability and half-life improvements, claim 5–10 face novelty challenges. Obviousness driven by known linkage chemistry If cross-linking activated PEG reagents with terminal groups and amide bond formation on proteins is routine, an examiner may consider applying this to alpha-galactosidase A an obvious variant absent a clear unexpected result. Indefiniteness / enablement if the assay definitions are non-standard Claim 1 and 11 anchor activity to “human plasma conditions for one hour” and “lysosomal conditions,” but the claims do not specify buffers, enzyme-to-condition ratios, or the definition of “substantially unchanged.” In some jurisdictions, these gaps can create enablement or definiteness disputes. Written description mismatch if sequence variants are broad Claims 12–15 permit varied source/identity/sequence while the structural linkage remains focused. If the specification support is enzyme-sequence general, that helps the patent. If not, it creates vulnerability. 3) Design-around options Competitors can design around by: using a non-PAG linker (breaking claim 5–10), using PAG but with non-terminal functional groups or non-amide linkages (breaking claim 6–8), producing non-dimer multimers (depending on interpretation of claim 5 as a fixed dimer), achieving performance improvements but not crossing the stated deltas (avoiding the ≥10% or ≥20% thresholds in claim 1/11). Practical relevance to Fabry ERT economics and product differentiation If a PEG-linked covalent multimer demonstrably: holds enzyme activity in plasma and lysosomal conditions, and extends circulating half-life by ≥20%, it supports two commercial levers: less frequent dosing (if half-life translates in vivo), and improved efficacy through more stable delivery and reduced loss. But the claim format also implies a regulatory and manufacturing burden: the product must remain within a defined performance window. That creates CMC risk because stability and half-life are sensitive to: PEG chain length distribution, degree of cross-linking, monomer integrity and aggregation profile. Key Takeaways US 10,280,414 centers on covalent multimerization of alpha-galactosidase A monomers via a non-native linking moiety, with PEG-based dimer embodiments (claims 5–10) as the most structurally enforceable core. Claim 1 and claim 11 rely on assay-linked performance thresholds (≥10% in plasma/lysosome conditions for specified windows and ≥20% half-life improvement) under a “selected characteristic” framework, making infringement possible through multiple alternative performance routes. The strongest enforceable narrowing occurs in claims 5–10 (PEG/PAG dimer, terminal groups, at least 5 units, at least one amide bond). Deviations in linker chemistry or bond formation are the most direct design-around levers. The most likely validity pressure points are overlap with prior art on covalent PEG cross-linking of proteins and the risk that performance thresholds depend on assay conditions not fully specified in the claim language. FAQs What is the single most important structural requirement in US 10,280,414? Covalently linking at least two alpha-galactosidase A monomers via a linking moiety that is not present in native alpha-galactosidase A (claims 1 and 3). Which claims most tightly define the chemical linker? Claims 5–10: PEG/PAG as the linking moiety, dimeric structure, terminal functional groups, PEG chain length at least 5 units, and at least one amide bond. Does claim 1 require plasma and lysosome stability simultaneously? No. Claim 1 requires the multimer to have at least one “characteristic” selected from the listed plasma/lysosome/half-life performance options. What performance metrics drive patent coverage? Activity deltas under “human plasma conditions” (1 hour), “lysosomal conditions” (immediate, 1 day, and 1 week), and a circulation half-life increase (≥20%) relative to native alpha-galactosidase A. What is the most direct way to avoid claims 5–10? Use a linkage mechanism that is not PEG/PAG terminally functionalized with an amide-forming bond, or avoid forming the specific PEG-bridged dimer architecture. References (APA) United States Patent 10,280,414 (claims provided). More… ↓ ⤷ Start Trial

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Genzyme Corporation	FABRAZYME	agalsidase beta	For Injection	103979	April 24, 2003	10,280,414	2037-06-29
Genzyme Corporation	FABRAZYME	agalsidase beta	For Injection	103979	October 10, 2003	10,280,414	2037-06-29
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Patent: 10,280,414

Summary for Patent: 10,280,414