United States Patent 11,826,360: Scope, Claim Construction, Validity Risks, and Migalastat Patent Landscape

U.S. Patent No. 11,826,360 protects compositions in which migalastat is bound to selected mutant forms of alpha-galactosidase A, with the composition containing Fabry-disease substrates or biological material. The patent is materially narrower than a patent covering migalastat, alpha-galactosidase A, or Fabry disease treatment generally. Its commercial relevance depends on whether a competing product or clinical protocol creates, measures, or uses the claimed migalastat-enzyme-substrate combination.

The strongest claim feature is the combination of a defined mutation list with migalastat binding and GL-3 or tissue localization. The principal weaknesses are the functional phrase "HEK assay amenable mutation," the breadth of "bound," the potential typo in claim 13, and the difficulty of proving infringement for biological compositions formed inside a patient.

What does U.S. Patent 11,826,360 claim?

The patent has two principal independent composition claims.

Claim	Claimed composition	Key limitation
1	Migalastat bound to mutant alpha-galactosidase A	Composition further comprises GL-3
13	Migalastat bound to mutant alpha-galactosidase A	Composition comprises an organ containing the complex

Claim 1 covers a composition comprising:

Migalastat;
an alpha-galactosidase A protein;
one of the listed mutations;
migalastat bound to that protein; and
globotriaosylceramide, or GL-3.

Claim 13 follows a different path. It does not expressly require GL-3 in the independent claim. Instead, it requires an organ containing migalastat bound to the specified mutant enzyme. Claim 19 then adds GL-3 to the organ composition.

The claims are composition claims, not conventional treatment-method claims. They do not expressly require administering migalastat, reducing GL-3, improving renal function, or treating a patient.

Which alpha-galactosidase A mutations are covered?

The mutation set in claim 1 includes 12 substitutions:

Mutation	Position	Amino-acid change
D55G	55	Aspartic acid to glycine
H125Y	125	Histidine to tyrosine
Q157H	157	Glutamine to histidine
L166S	166	Leucine to serine
N215I	215	Asparagine to isoleucine
K240N	240	Lysine to asparagine
G261R	261	Glycine to arginine
L275V	275	Leucine to valine
N278Y	278	Asparagine to tyrosine
W287L	287	Tryptophan to leucine
K308E	308	Lysine to glutamic acid
P343T	343	Proline to threonine

The dependent claims create overlapping subsets. Claim 3 is the narrowest mutation subset and covers Q157H, L166S, and K240N. Claims 2, 4, 5, and 6 remove different mutations from the claim 1 list.

Does claim 13 contain a mutation-number error?

Yes. The text supplied for claim 13 recites "N2151," whereas claim 1 recites "N215I." The latter is the chemically coherent notation: asparagine at position 215 replaced by isoleucine. "N2151" appears to be a transcription or OCR error, with the final character "I" rendered as the numeral "1."

The legal effect depends on the issued patent and its prosecution history. If the issued document itself contains "N2151," the issue may create an indefiniteness, correction, or claim-construction dispute. If the official issued claim uses "N215I," the discrepancy is not substantive.

What does "HEK assay amenable mutation" mean?

The phrase identifies mutations that permit alpha-galactosidase A activity or stabilization in a human embryonic kidney-cell assay in the presence of migalastat. The claim, however, does not state:

the HEK cell line;
the assay protocol;
the expression vector;
the migalastat concentration;
the activity threshold;
the required degree of stabilization; or
whether the assay measures enzyme activity, trafficking, lysosomal localization, or another parameter.

That creates a potential indefiniteness and written-description issue. A court would likely interpret the phrase using the specification, cited assay methods, and prosecution record. The mutation list provides an objective anchor, but the functional language may still be litigated if a party disputes whether a particular variant is "HEK assay amenable."

How broad is the requirement that migalastat be "bound" to alpha-galactosidase A?

"Bound" is broader than covalent attachment. In the pharmacological context, it would ordinarily encompass noncovalent binding of migalastat to the enzyme's active site or another binding site. Migalastat is a pharmacological chaperone. It stabilizes certain mutant alpha-galactosidase A proteins, improves folding or trafficking, and can increase lysosomal enzyme activity in responsive variants.[1]

The claim does not specify:

a binding constant;
a stoichiometric ratio;
a binding site;
a minimum residence time;
a conformational state; or
a measurable increase in enzyme activity.

A competitor could therefore challenge the claim as indefinite or argue that transient or incidental association does not satisfy "bound." The patentee would likely rely on the specification's biochemical and cellular data to establish the ordinary meaning in context.

What is the role of GL-3 in claims 1 through 12?

GL-3 is globotriaosylceramide, a lysosomal glycosphingolipid that accumulates in Fabry disease. In claims 1 through 12, GL-3 is not merely a disease indication. It is a compositional limitation.

Claim 1 requires that the composition further comprise GL-3. Claims 8 and 9 narrow the composition to:

white blood cells containing GL-3; or
plasma containing GL-3.

Claim 17 extends the concept to tissue containing GL-3, and claim 18 covers cells containing GL-3.

The GL-3 limitation creates a substantial infringement issue. A commercial migalastat capsule does not inherently contain GL-3, mutant alpha-galactosidase A, or a patient-derived biological compartment. A plaintiff would need to show that the accused product or system includes all required elements in the claimed composition.

What do the plasma and lyso-Gb3 concentration claims cover?

Claim 10 specifies plasma containing migalastat at approximately 1 to 2,191 ng/mL. Claim 12 specifies plasma lyso-Gb3 at approximately 9.3 to 13.1 nM/L.

These limitations are narrow in numerical terms but potentially difficult to enforce. The relevant questions would include:

whether "about" permits a defined measurement tolerance;
whether the concentration must be present at the same time as the claimed enzyme complex;
whether the range is measured before or after dosing;
whether sample handling changes the result; and
whether the claim covers naturally occurring patient plasma without an affirmative act by the accused party.

The concentration claims may have evidentiary value in clinical-monitoring contexts, but they do not necessarily create broad control over all migalastat-treated patients. Natural biological variation and sampling conditions could also create claim-construction disputes.

What organs and tissues are protected?

Claims 13 through 16 cover organ compositions containing the migalastat-enzyme complex. The expressly identified organs are:

Claim	Organ or biological material
13	Any organ
14	Heart
15	Kidney
16	Skin
19	Organ containing the complex and GL-3

Claims 17 and 18 separately cover tissue and cells containing GL-3 and the migalastat-bound enzyme.

The kidney limitation has the closest biological relationship to Fabry disease, which commonly produces renal involvement. The heart limitation is relevant to Fabry cardiomyopathy. Skin and vascular tissues can also contain disease-associated storage material.

These claims appear directed to demonstrated pharmacodynamic distribution or intracellular engagement rather than to a conventional drug formulation.

How does the patent compare with the Galafold product patent estate?

Galafold is the U.S. brand for migalastat hydrochloride, marketed by Amicus Therapeutics for adults with Fabry disease who have an amenable alpha-galactosidase A variant.[2] The approved product is an oral small-molecule drug. U.S. Patent 11,826,360, based on the supplied claims, is directed to biological compositions involving the drug and mutant enzyme in the presence of disease substrates.

Issue	Galafold product protection	U.S. Patent 11,826,360
Protected subject matter	Migalastat drug and approved use, depending on listed rights	Migalastat bound to mutant alpha-galactosidase A
Dosage form	Oral capsule	No capsule or dosage-form limitation
Active ingredient	Migalastat	Migalastat plus mutant enzyme complex
Patient substrate required	No	GL-3 required in claims 1-12 and 19
Organ or tissue required	No	Required by claims 13-19
Typical commercial target	Generic migalastat	Products or processes creating or evaluating the claimed complex
Biosimilar relevance	None for migalastat as a small molecule	Limited; the claims concern an enzyme-containing composition

The patent does not appear, from the claim text alone, to cover every generic version of migalastat. A generic product containing migalastat hydrochloride would not ordinarily satisfy the enzyme, mutation, and GL-3 limitations merely because patients taking it have endogenous alpha-galactosidase A and GL-3.

What is the FDA and Orange Book relevance?

Migalastat received FDA approval for Fabry disease in 2018 under the Galafold brand.[2] The FDA label limits use to patients with an amenable mutation, based on an in vitro assay used to identify responsive variants.

The Orange Book relevance of U.S. Patent 11,826,360 depends on whether the patent was submitted for listing against the applicable Galafold NDA and accepted by FDA. The claim architecture is atypical for an Orange Book-listed drug patent because it does not expressly claim:

migalastat as a compound;
migalastat hydrochloride;
a capsule;
a dosage regimen;
a pharmaceutical formulation; or
a method of treating Fabry disease.

A patent can be commercially important without being Orange Book listed. If it is not listed, it would generally not create the standard 30-month stay associated with an accepted Paragraph IV certification. If it is listed, the precise listed claims and FDA publication status would control.

Are Paragraph IV challenges likely to target this patent?

A Paragraph IV challenge would be commercially useful only if the patent is listed against the relevant migalastat NDA and the generic applicant's product is alleged to infringe. The supplied claims create several possible non-infringement positions:

A generic capsule does not contain GL-3.
The capsule does not contain mutant alpha-galactosidase A.
The product does not contain an organ, tissue, plasma, or white blood cells.
Any enzyme binding occurs only after administration and within a patient's biological environment.
The accused product does not meet the specified mutation or concentration limitations.

Potential invalidity positions include indefiniteness, lack of written description, enablement, anticipation, obviousness, and patent-eligibility arguments directed to claims that characterize naturally occurring patient samples or biological states.

The practical risk is therefore more likely to arise from patent-listing and claim-construction questions than from ordinary formulation infringement.

What method-of-use and formulation protection exists?

The supplied claims contain no conventional method-of-use claim. Claim 7 states that migalastat stabilizes the alpha-galactosidase A protein, but it remains a dependent composition claim. It does not recite administering migalastat to a patient or treating Fabry disease.

The claims also contain no express formulation protection. They do not specify:

excipients;
capsule composition;
particle size;
crystalline form;
salt or polymorph;
dissolution profile;
release profile; or
manufacturing process.

A separate Galafold patent family could protect those subjects, but that protection cannot be attributed to U.S. Patent 11,826,360 from the supplied claims.

How strong is the patent estate?

Strengths

The mutation list is concrete and technically specific.
Claims 1 and 13 use multiple biological limitations that can distinguish ordinary migalastat products.
Claims 14 and 15 connect the claimed complex to clinically relevant heart and kidney tissue.
Claims 10 and 12 provide quantitative concentration limitations.
Claims 8, 9, 17, and 18 extend the claims across blood, plasma, tissue, and cells.

Weaknesses

The claims are composition claims for biological states that may arise inside a treated patient.
"HEK assay amenable" may require extensive specification-based interpretation.
"Bound" lacks an express biochemical threshold.
GL-3 and lyso-Gb3 are endogenous disease biomarkers.
The claim 13 "N2151" wording may create a correction or indefiniteness issue if present in the issued patent.
The claims do not directly cover the commercial oral drug product.
Proving direct infringement may require access to patient samples or intracellular material.

The estate is stronger as a blocking position against specific enzyme-replacement, cell-based, analytical, or biomarker-enabled programs than as a direct barrier to generic migalastat capsules.

What biosimilar and competitive risks exist?

Migalastat is a small molecule, so an Abbreviated New Drug Application, not a biosimilar application, would be the expected pathway for a generic oral product. Biosimilar risk is more relevant to competing enzyme-replacement products such as agalsidase beta and newer biologic therapies.

Fabry treatment competition includes:

migalastat for amenable variants;
agalsidase beta enzyme replacement;
agalsidase alfa in markets where approved;
pegunigalsidase alfa;
investigational gene therapies;
next-generation enzyme-replacement and substrate-reduction programs.

U.S. Patent 11,826,360 is most relevant to programs that combine migalastat with mutant alpha-galactosidase A, characterize intracellular chaperone-enzyme complexes, or use GL-3 and lyso-Gb3 as part of a claimed composition.

What litigation and settlement issues should investors monitor?

The principal litigation triggers are:

A generic applicant challenges Galafold patent listings under Paragraph IV.
A competing enzyme or gene-therapy developer uses migalastat as a pharmacological chaperone.
A diagnostic or clinical-monitoring company measures the claimed plasma or tissue composition.
A product candidate uses one of the listed alpha-galactosidase A mutations.
The parties dispute whether the claimed complex exists in vivo and whether that state is attributable to the accused product.

No settlement terms, Paragraph IV notice, or case-specific litigation conclusion can be derived from the claim text alone. The patent should be assessed separately from any Galafold compound, formulation, method-of-use, or regulatory-exclusivity rights.

Key Takeaways

U.S. Patent 11,826,360 is directed to migalastat bound to selected mutant alpha-galactosidase A proteins.
Claims 1 through 12 require GL-3, directly or through biological samples and tissues.
Claims 13 through 16 cover organs containing the migalastat-enzyme complex.
Claim 19 adds GL-3 to the organ composition.
The patent does not directly claim migalastat capsules or migalastat treatment generally.
The typo-like "N2151" in claim 13 should be compared with the official issued patent and prosecution record.
Generic capsule infringement is not apparent from the supplied claims.
The principal legal vulnerabilities are indefiniteness, enablement, written description, natural-state composition issues, and proof of direct infringement.
Biosimilar competition is secondary because migalastat is a small molecule; generic-drug and enzyme-replacement competition are more relevant.
Orange Book impact depends on whether this specific patent was accepted for listing against the Galafold NDA.

FAQs

Does U.S. Patent 11,826,360 cover all patients taking Galafold?

No. The claims require a specified mutant alpha-galactosidase A protein and additional biological composition limitations, including GL-3, plasma, tissue, cells, or organs in different claims.

Can a generic migalastat manufacturer avoid this patent?

A generic may have substantial non-infringement arguments because the claims do not expressly cover an oral capsule and require biological components not ordinarily present in the marketed drug product.

Does the patent cover alpha-galactosidase A enzyme replacement therapy?

Not broadly. It covers compositions containing migalastat bound to specified mutant alpha-galactosidase A proteins. An enzyme-replacement product without migalastat would not satisfy the central combination requirement.

Are lyso-Gb3 concentration claims treatment claims?

No. Claim 12 is a composition claim directed to plasma containing lyso-Gb3 within a stated concentration range, together with the limitations inherited from claim 11 and claim 9.

Does the patent protect a new migalastat formulation?

No formulation limitation appears in the supplied claims. The claims do not recite excipients, dosage form, release characteristics, salt, polymorph, or manufacturing conditions.

References

U.S. Patent No. 11,826,360. (2023). Compositions comprising migalastat bound to alpha-galactosidase A proteins. United States Patent and Trademark Office.
U.S. Food and Drug Administration. (2018). Galafold (migalastat) prescribing information. FDA.
U.S. Food and Drug Administration. (2023). Orange Book: Approved drug products with therapeutic equivalence evaluations. FDA.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Amicus Therap Us	GALAFOLD	migalastat hydrochloride	CAPSULE;ORAL	208623-001	Aug 10, 2018		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial		Y			⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	111971	⤷ Start Trial
Argentina	131106	⤷ Start Trial
Argentina	131107	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 11,826,360

Which drugs does patent 11,826,360 protect, and when does it expire?

Summary for Patent: 11,826,360