US Patent 10,383,864: Fabry Disease Migalastat Dosing Claims and Patent Landscape

US Patent No. 10,383,864 protects specific methods of treating Fabry disease with migalastat, also identified chemically as 1-deoxygalactonojirimycin, on an every-other-day schedule. The core protected features are the patient population, Fabry disease indication, dose frequency, and, in several claims, a 50 mg to 250 mg dose range. The patent does not claim migalastat as a compound, a composition of matter, or a manufacturing process.

The patent is commercially relevant to Galafold, the oral migalastat hydrochloride product marketed by Amicus Therapeutics. Its claims are method-of-use claims directed to dosing and administration rather than to the active pharmaceutical ingredient itself.

What does US Patent 10,383,864 cover?

The patent covers treatment of Fabry disease in a human patient by administering 1-deoxygalactonojirimycin or a salt of that compound every other day.

The independent claims divide into three principal coverage groups:

Claim group	Core subject matter	Key limitations
Claims 1-9	Migalastat or a salt	Fabry disease, human patient, approximately 50-250 mg every other day
Claims 10-18	Migalastat hydrochloride	Fabry disease, human patient, approximately 50-250 mg every other day
Claims 19-20	Migalastat or a salt	Therapeutically effective dose every other day, with fasting; claim 20 specifies approximately 150 mg

Claim 1 is the principal broad dose-range claim. Claim 10 is narrower because it requires migalastat hydrochloride rather than the broader category of migalastat or any salt. Claim 19 is potentially important because it does not specify a dose range, but it requires the administration to occur with a food restriction.

Chemical scope of 1-deoxygalactonojirimycin

1-Deoxygalactonojirimycin is the chemical name associated with migalastat. Claims 1 and 19 cover the free compound and salts. Claims 10-18 expressly require migalastat hydrochloride.

The salt language broadens claims 1 and 19 beyond the hydrochloride form. A product containing a different pharmaceutically acceptable salt could potentially fall within those claims if all remaining limitations are met. The claims do not expressly require a particular crystalline form, polymorph, particle size, excipient system, or release profile.

What are the key limitations in the patent claims?

The claims require a combination of limitations. A competing product or regimen would generally need to satisfy each limitation of an asserted claim for literal infringement.

Fabry disease treatment

Every independent claim requires treatment of Fabry disease in a human patient in need thereof. The patent therefore does not cover every use of migalastat. Uses for other lysosomal storage disorders, nontherapeutic research, or treatment outside the claimed disease may fall outside the literal scope of these claims.

Every-other-day administration

Every-other-day dosing is the central temporal limitation. A regimen administered once daily, twice weekly, or according to an alternative intermittent schedule would not literally satisfy the phrase "every other day," subject to the interpretation of equivalent dosing and the facts of a particular case.

The every-other-day limitation is commercially significant because the FDA-approved Galafold regimen is one 123 mg capsule taken orally every other day. The approved regimen is expressed in terms of 123 mg migalastat hydrochloride, corresponding to 100 mg of migalastat free base. The FDA label also requires administration on an empty stomach. [1]

Dose range

Claims 1 and 10 recite approximately 50 mg to approximately 250 mg every other day. Claims 8 and 17 narrow the range to approximately 50 mg to approximately 150 mg. Claims 9 and 18 cover approximately 150 mg to approximately 250 mg.

The use of "about" creates a potential claim-construction issue. It generally permits some variation around the stated numerical boundaries, but the permissible range depends on the specification, prosecution history, technological context, and evidence concerning how a person skilled in the art would understand the term.

The claims do not clearly state whether the dose is measured as migalastat free base, migalastat hydrochloride, or total salt weight in claims that use the generic chemical name. Claims 10-18 identify migalastat hydrochloride directly. Product-label comparisons should therefore distinguish active moiety from salt weight.

Oral dosage form

Claims 2, 3, 11, and 12 require an oral dosage form. The listed forms are tablets, capsules, and solutions. Claims 1 and 10 are broader because the independent claims do not expressly require oral administration.

The approved Galafold product is an oral capsule. [1] A generic or follow-on product administered orally would face the dependent claims if it otherwise meets the Fabry disease, dosing, and frequency requirements.

Food restriction

Claims 4, 13, 19, and 20 require that the patient not eat food from approximately two hours before to approximately two hours after administration. This limitation is narrower than a general "empty stomach" requirement because it defines a specific pre-dose and post-dose period.

The FDA prescribing information instructs patients to take Galafold on an empty stomach and not to consume food at least two hours before and two hours after the dose. [1] This correspondence increases the relevance of these claims to the marketed product and to proposed generic labeling.

Alpha-galactosidase A activity

Claims 5 and 14 state that migalastat enhances alpha-galactosidase A activity. These are dependent claims. They do not expressly require a specified enzyme-activity threshold, percentage increase, assay, or biomarker result.

The limitation could raise an evidentiary issue in litigation. A patentee may argue that the limitation describes the biological function of the administered drug. An accused infringer may challenge whether the claim requires proof of a measurable activity increase in each patient or merely recites the intended pharmacological effect.

Male and female patients

Claims 6, 7, 15, and 16 separately recite male and female patients. These claims do not materially expand the broad independent claims because the independent claims already cover a human patient. They create gender-specific dependent positions but do not impose a disease genotype, age, renal-function, or mutation-amenability requirement.

How broad are the independent claims?

Claim 1

Claim 1 requires:

A method of treating Fabry disease.
A human patient in need of treatment.
Administration of 1-deoxygalactonojirimycin or a salt.
Approximately 50 mg to approximately 250 mg.
Every-other-day administration.

The claim does not require:

Oral delivery.
Migalastat hydrochloride specifically.
A tablet or capsule.
A food restriction.
Male or female sex.
A demonstrated increase in alpha-galactosidase A activity.
A particular Fabry mutation.
A specific baseline enzyme level.
A specified treatment duration.
A particular clinical endpoint.

This makes claim 1 the principal method-of-use risk for a product using an every-other-day migalastat regimen within the claimed dose range.

Claim 10

Claim 10 is similar to claim 1 but requires migalastat hydrochloride. It is narrower chemically but closely aligned with the commercial product.

For an oral migalastat hydrochloride product dosed every other day at approximately the approved dose, claim 10 and its oral-dosage-form dependents are more directly relevant than claim 1 because they identify the marketed salt.

Claim 19

Claim 19 requires every-other-day administration and the defined food restriction, but it does not specify a numerical dose. This claim could reach a broader dose spectrum than claims 1 and 10 if the administered amount qualifies as a therapeutically effective dose.

Its practical scope depends on how "therapeutically effective dose" is construed and proved. Claim 20 then narrows the regimen to approximately 150 mg every other day.

What patent protection does US 10,383,864 not provide?

US 10,383,864 does not appear, based on the supplied claims, to provide the following types of protection:

Protection category	Coverage in the supplied claims
Migalastat compound	No composition-of-matter claim
Migalastat hydrochloride composition	No standalone composition claim
Tablet formulation	Only dependent method claims
Capsule formulation	Only dependent method claims
Solution formulation	Only dependent method claims
Manufacturing process	No process claim
Solid-state form or polymorph	No express claim
Packaging or device	No claim
Diagnostic method	No claim
Specific GLA mutation	No express claim
Biomarker threshold	No express claim
Combination therapy	No express claim
Pediatric treatment	No express claim
Renal-dose adjustment	No express claim

The patent therefore operates primarily as a dosing-regimen patent. Separate patents may protect the compound, chemical synthesis, pharmaceutical formulation, patient-selection method, or other treatment schedules.

What is the FDA and Orange Book status of Galafold?

Galafold is FDA-approved as an oral treatment for adults with Fabry disease who have an amenable GLA variant. The FDA-approved product contains migalastat hydrochloride and is administered as one capsule every other day on an empty stomach. [1]

FDA approval and patent listing are separate issues. The Orange Book identifies patents submitted by the new drug application holder that claim the drug or an approved method of using the drug. The relevant Orange Book listing must be checked by product, NDA, patent number, and expiration date because listings can change through delisting, correction, expiry, or regulatory updates. [2]

A patent listing does not establish that every listed claim is valid or infringed. It creates a statutory framework for generic applicants that file an Abbreviated New Drug Application and make a Paragraph IV certification.

Regulatory features relevant to generic entry

A generic applicant seeking approval before listed patent expiry may certify that:

The patent is invalid.
The patent is unenforceable.
The generic product will not infringe the patent.
The applicant will wait for patent expiry under another certification pathway.

A first substantially complete Paragraph IV certification can trigger a 45-day period for the patent holder to file an infringement action. A timely action can impose a 30-month stay of final FDA approval, subject to statutory exceptions and court developments. [3]

For a method-of-use patent, a generic applicant may also seek a label that omits the patented indication or dosing instruction where the FDA labeling and applicable patent-certification rules permit a section viii statement. The feasibility of a carve-out depends on the exact Orange Book listing, the patented use, the approved labeling, and whether the proposed label still induces the patented method.

When does US Patent 10,383,864 lose exclusivity?

The enforceable term depends on the patent's effective filing date, priority chain, patent-term adjustment, patent-term extension, terminal disclaimers, and any regulatory extension. The face of the patent and USPTO Patent Center records control the operative term. [4]

A practical term analysis should separate three dates:

Date type	Relevance
Nominal expiration	Twenty years from the relevant nonprovisional filing date, subject to adjustments
Patent-term adjustment	Adds time for qualifying USPTO examination delays
Patent-term extension	May extend an eligible patent for regulatory review, subject to statutory limits

A precise expiration date cannot be established from the claims alone. The claim text does not disclose the priority chain, patent-term adjustment, terminal disclaimer status, or any patent-term extension. The patent's current legal status also requires a live USPTO and Orange Book review.

What Paragraph IV challenges could target the patent?

A Paragraph IV challenge to US 10,383,864 could focus on invalidity or noninfringement theories involving:

Anticipation

The challenger could argue that prior art disclosed:

Fabry disease treatment with migalastat.
Every-other-day dosing.
A dose within approximately 50 mg to 250 mg.
The food-restriction schedule.
Migalastat hydrochloride administration.

Anticipation requires a single prior-art reference to disclose every claim limitation, arranged as claimed.

Obviousness

Obviousness arguments could combine known migalastat pharmacology, prior clinical dosing, pharmacokinetic data, food-effect studies, and known Fabry treatment protocols. The key issue would be whether a skilled person would have had a reasonable expectation that an every-other-day regimen within the claimed dose range would treat Fabry disease effectively.

The patent holder would likely rely on clinical results, dosing advantages, pharmacokinetic behavior, patient adherence, and unexpected efficacy or safety findings to defend the claims.

Written description and enablement

The claims cover a broad dose range, multiple salts, male and female patients, oral and non-oral administration under the independent claims, and a therapeutically effective dose without a numerical limitation in claim 19. A challenger could argue that the specification does not adequately support or enable the full breadth of those categories.

The strength of such arguments depends on the examples, clinical data, pharmacological disclosure, salt descriptions, and dosing data in the patent specification.

Indefiniteness

Potential terms for challenge include:

"About 50 to about 250 mg."
"Every other day."
"Patient in need thereof."
"Therapeutically effective dose."
"Enhances alpha-galactosidase A activity."

These terms are common in pharmaceutical patent drafting, but their enforceability depends on whether the specification and prosecution history provide a reasonably certain scope.

What generic launch scenarios exist?

A generic applicant could pursue several pathways:

Scenario	Commercial implication
Wait for all relevant patents to expire	Lowest litigation exposure, but delayed entry
File Paragraph IV certification	Earlier approval opportunity with patent litigation risk
Use a section viii carve-out	Potentially avoids a patented method if the label can omit the use
Challenge only the dosing patent	May leave compound, formulation, or other method patents as barriers
Launch at risk after litigation or dismissal	Exposure to damages, injunction, and market disruption
Launch with a non-infringing schedule	May avoid literal infringement but could lose the approved commercial dosing advantage

A generic product labeled for Fabry disease and administered every other day at a dose within the claimed range would present the clearest infringement risk under claims 1 and 10. A product using a different schedule could reduce literal infringement risk but could create regulatory, clinical, or commercial disadvantages.

Induced infringement risk may also arise from labeling, promotional materials, physician instructions, or other conduct that encourages administration according to the patented regimen. The analysis would depend on the final approved label and the evidence of intent.

How strong is the patent estate around migalastat?

The strength of the overall migalastat estate cannot be determined from US 10,383,864 alone. A commercial freedom-to-operate analysis should map at least five patent categories:

Composition-of-matter patents covering migalastat or salts.
Manufacturing patents covering synthesis, intermediates, and purification.
Formulation patents covering capsules, excipients, stability, or solid forms.
Method-of-use patents covering Fabry disease, mutation amenability, and dose schedules.
Regulatory and pediatric exclusivity affecting FDA approval timing.

US 10,383,864 is strongest where the proposed product mirrors the approved Galafold regimen: migalastat hydrochloride, oral administration, every other day, and food restriction. Its relative weakness is that it does not claim the active ingredient itself and does not expressly require the commercial capsule formulation in its independent claims.

Geographic coverage

US 10,383,864 has territorial effect in the United States only. It does not directly block manufacture, sale, or use in Europe, Japan, China, or other markets. Parallel national patent families must be analyzed separately.

For multinational launch planning, the relevant questions include:

Whether corresponding applications were granted in major markets.
Whether claim scope differs by jurisdiction.
Whether foreign claims survived opposition or examination.
Whether supplementary protection certificates or regulatory extensions apply.
Whether local patents cover the approved product or only specific regimens.

Manufacturing and supply-chain barriers

The patent does not claim a manufacturing process in the supplied claims. A manufacturer could therefore face separate process or intermediate patents even if it avoids the asserted dosing claims. Conversely, avoiding a process patent would not eliminate risk under a method-of-use patent if the finished product is administered according to the claimed regimen.

How does US 10,383,864 compare with formulation and method-of-use patents?

US 10,383,864 is a dosing method patent, not a formulation patent.

Patent type	Typical protected subject matter	Relevance to this patent
Composition patent	Migalastat molecule or salt	Separate estate
Formulation patent	Capsule, tablet, excipients, stability	Not claimed expressly
Method-of-use patent	Fabry treatment regimen	Primary category
Patient-selection patent	Amenable GLA variants	Not claimed expressly
Manufacturing patent	Synthesis or purification	Not claimed
Combination patent	Migalastat with another treatment	Not claimed

This distinction matters in litigation. Invalidating or avoiding US 10,383,864 may not clear all patent barriers to generic Galafold entry. A generic applicant must assess the complete Orange Book listing and any non-Orange Book patents that may support litigation or commercial deterrence.

What litigation and settlement issues affect the patent?

A current litigation conclusion cannot be drawn from the claim text. Patent litigation status must be confirmed through PACER, USPTO Patent Center, FDA Orange Book updates, and any publicly disclosed Amicus securities filings.

If a Paragraph IV case exists, relevant commercial terms may include:

The first permissible launch date.
A licensed launch date.
Restrictions on dosage strength or labeling.
Authorized-generic arrangements.
Waivers or covenants relating to particular claims.
Acceleration or forfeiture provisions.
Settlement terms governing other patents in the estate.

A settlement involving another Galafold patent would not automatically resolve US 10,383,864 unless the agreement expressly covers this patent or the relevant claims.

What is the commercial exposure associated with the patent?

The patent's commercial exposure tracks the portion of Galafold sales dependent on the every-other-day migalastat regimen. Because the approved product uses that regimen, the patent is directly relevant to a generic seeking to reproduce the branded therapy.

Revenue exposure should be modeled against:

Galafold annual net sales.
The expected first generic filing date.
The number of Orange Book patents remaining.
Probability of a Paragraph IV challenge.
Probability of patent invalidation or noninfringement.
Potential launch-at-risk behavior.
Payer substitution and generic penetration.
Availability of alternative Fabry treatments, including enzyme replacement therapies.

No reliable revenue figure can be assigned to US Patent 10,383,864 alone without isolating the patent's contribution from the broader Galafold patent and regulatory exclusivity portfolio.

Key Takeaways

US 10,383,864 is a method-of-use patent for treating Fabry disease with migalastat every other day.
Claims 1 and 10 are the principal independent claims for dose-defined regimens.
Claims 1-9 cover 1-deoxygalactonojirimycin or a salt; claims 10-18 specifically cover migalastat hydrochloride.
The principal numerical range is approximately 50 mg to 250 mg every other day.
Claim 19 adds the two-hour pre-dose and two-hour post-dose food restriction but does not specify a numerical dose.
The claims do not cover the compound, a standalone capsule formulation, a manufacturing process, or a specific GLA mutation.
The claims closely correspond to the FDA-approved Galafold regimen of oral migalastat hydrochloride every other day on an empty stomach. [1]
A generic using the same active ingredient, salt, schedule, and dose would face the clearest method-of-use infringement risk.
Exact patent expiry requires review of the priority chain, patent-term adjustment, terminal disclaimers, and any patent-term extension.
The patent is only one component of the broader US and international migalastat patent estate.

FAQs

Does US 10,383,864 cover all migalastat products?

No. It covers specified methods of treating Fabry disease. It does not claim migalastat as a compound or every formulation containing migalastat.

Does a daily migalastat regimen infringe the patent?

A daily regimen would not literally meet the every-other-day limitation. Other patents, regulatory requirements, or infringement theories could still be relevant.

Does the patent cover migalastat free base?

Claims 1-9 and 19-20 refer to 1-deoxygalactonojirimycin or a salt thereof. Claims 10-18 specifically require migalastat hydrochloride.

Can a generic omit the patented dosing instructions from its label?

Possibly, but the feasibility depends on FDA labeling rules, the Orange Book listing, the approved indication, the proposed label, and whether the remaining label induces the patented use.

Is the FDA-approved 123 mg Galafold capsule within the patent's dose range?

The product contains 123 mg of migalastat hydrochloride, commonly described in FDA materials as equivalent to 100 mg of migalastat free base. That regimen falls within the claimed approximately 50 mg to approximately 250 mg range when assessed on the relevant active-moiety basis. [1]

References

U.S. Food and Drug Administration. (2024). Galafold (migalastat) prescribing information. FDA.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
U.S. Code, 21 U.S.C. § 355(j).
U.S. Patent and Trademark Office. (2024). Patent Center: U.S. Patent No. 10,383,864. USPTO.

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	10,383,864	⤷ Start Trial				THE TREATMENT OF FABRY PATIENTS	⤷ 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
European Patent Office	2787345	⤷ Start Trial	300843	Netherlands	⤷ Start Trial
European Patent Office	2787345	⤷ Start Trial	PA2016033	Lithuania	⤷ Start Trial
European Patent Office	2787345	⤷ Start Trial	122016000090	Germany	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Summary for Patent: 10,383,864