US Patent 12,433,863 (Acetyl-Leucine): What Is Claimed, What It Covers, and How It Sits in the Landscape
US Patent 12,433,863 claims a clinical outcome-driven method for treating, delaying, or reversing lysosomal storage disorders (LSDs) using acetyl-leucine (and salts) administered for at least ~3 months, with benefits anchored to improved SARA scores (and optionally other disability/clinical scales).
This is a use/treatment claim set with a broad disease genus (multiple LSDs) and a narrower “effect” anchor (improved Scale for the Assessment and Rating of Ataxia (SARA) compared to baseline), plus an enantiomer/amount module and downstream dependent claim layers.
What are the core claim elements in US 12,433,863?
1) Active ingredient scope
- Acetyl-leucine or pharmaceutically acceptable salts of acetyl-leucine (independent claims 1-3).
2) Indication scope
A defined list of lysosomal storage disorders (independent claims 1-3), including:
- Niemann-Pick type C, Tay-Sachs (including AB variant), Sandhoff
- Niemann-Pick type A and B
- Fabry disease
- Neuronal ceroid lipofuscinoses
- Krabbe disease
- Farber disease
- Gaucher disease
- Metachromatic leukodystrophy
- Multiple sulphatase deficiency
- Mucolipidosis II and III
- MPS III and MPS VII
- GM1 gangliosidosis
- Aspartylglucosaminuria
Dependent claims narrow subsets (e.g., NP-A/B/C; Tay-Sachs/Sandhoff/MPS II/III/GM1 group; NP-C as a specific carve-out).
3) Duration requirement
- At least about 3 months (independent claims 1 and 3).
- Independent claim 2 uses “duration chosen from” and then states at least about 3 months (claim text as provided).
4) Clinical outcome requirement
- Subject achieves an improved SARA assessment compared to before administration (independent claims 1-3).
- Dependent claims add:
- “At least 1 point improvement in SARA” (claims 12, 16, 20).
- Alternative or additional assessments from a defined list (claims 13, 17, 21).
5) Dose and formulation/enantiomer options
Dependent modules add:
- Acetyl-DL-leucine (claim 4).
- Enantiomer/enantiomeric excess:
- enantiomeric excess of L or D (claim 5),
- single enantiomer (claim 6),
- specifically single enantiomer L (claim 7).
- Daily dose range:
- ~1 g to ~15 g/day (claim 8).
- Narrowed to ~1 g to ~10 g/day for certain NP-A/B/C grouping (claim 10).
- Dose range repeated for delay claim (claim 14) and reversal claim (claim 18).
How do claims 1 to 3 define the therapeutic “triptych”: treat, delay, reverse?
| Independent claim |
Therapeutic framing |
Disease/time anchor |
Outcome anchor |
| Claim 1 |
Treating an LSD or symptoms |
Acetyl-leucine for ≥ ~3 months |
Improved SARA vs baseline |
| Claim 2 |
Delaying progression of LSD or symptoms over time |
Duration ≥ ~3 months |
Improved SARA vs baseline (as written) compared to before administration |
| Claim 3 |
Reversing progression over time |
Acetyl-leucine for ≥ ~3 months |
Improved SARA vs baseline |
Key structural observation: even the “delay” and “reverse” claims are still tied to SARA improvement vs before administration. The difference is the semantic characterization of clinical effect (treat/delay/reverse), while the measurable hook remains SARA improvement.
What do the dependent claims add to enforce scope and design-arounds?
Enantiomer and stereochemical control
- Acetyl-DL-leucine (claim 4)
- Enantiomeric excess (claim 5)
- Single-enantiomer forms (claims 6-7)
- claim 7 fixes the L-enantiomer.
Practical impact: if a competitor uses a racemate, single-enantiomer D, or L-enriched product, these dependent claims create multiple entry points for infringement arguments. Even if the independent claim covers “acetyl-leucine,” the dependent claims support sublayer enforcement around specific commercial forms.
Dose bands
- General: 1 g to 15 g/day (claim 8)
- NP-A/B/C subset: 1 g to 10 g/day (claim 10)
- Parallel dose statement across delay and reversal claims (claims 14 and 18)
Practical impact: dose design-arounds must still satisfy the independent claims’ “therapeutically effective amount” and the ≥3-month duration and SARA improvement limitations. The dependent dose claims add hard numerical boundaries for key product labeling/regimen.
Disease subset carve-outs
- Claim 9: NP-A/B/C
- Claim 11: Tay-Sachs, Sandhoff, NP-A, NP-C, mucolipidosis II, MPS III, GM1
- Claims 22-24: NP-C only, tied to treat/delay/reverse family
Practical impact: NP-C is emphasized repeatedly, creating separate lanes for a launch strategy focused on NP-C clinical populations.
Quantified clinical response
- At least 1 point SARA improvement (claims 12, 16, 20)
This is a numerically enforceable response threshold layered onto the broader “improved SARA” language.
Assessment expansion beyond SARA
The scale set includes:
- Functional SARA (fSARA)
- Spinocerebella Ataxia Functional Index (SCAFI)
- Modified Disability Rating Scale (mRDS)
- Niemann Pick Type-C Clinical Severity Scale (NPC-CSS)
- 5-domain NPC-CSS
- EuroQol 5-Dimension 5-Level (5Q-5D-5L)
Claims 13, 17, 21 expand the evidence framework to these endpoints in addition to SARA. Dependent claim 25/26/27 tie fSARA to specific family claims.
Practical impact: this improves enforcement leverage for programs that prove benefit through functional endpoints, patient-reported outcomes, or NP-C-specific severity instruments, even if SARA is not the only metric in the clinical package.
What is the effective claim “scope” for competitors?
A. Method scope is patient-by-patient and endpoint-linked
The claims are not “composition” claims. They are method-of-treatment claims requiring:
1) administering acetyl-leucine (or salt),
2) to a subject with a specified LSD,
3) for at least about 3 months,
4) achieving an improved SARA compared to baseline.
This creates a causation and measurable effect gate: for liability analysis, the operational question becomes whether clinical use results in SARA improvement.
B. Commercial form options are buffered by dependent claim diversity
Across claims 4-7, the patent anticipates:
- racemate (DL),
- enantiomeric excess,
- single-enantiomer L,
- and single-enantiomer D via the “L or D” framing (claim 5).
A manufacturer cannot easily exit all sub-claims by switching from DL to L-only, because dependent claims explicitly cover multiple stereochemical states.
C. Dose range provides enforcement targets but does not eliminate “therapeutically effective amount” coverage
Even if a regimen stays outside 1-15 g/day, the independent claims still turn on “therapeutically effective amount.” That wording can be contested, but it does not provide a clean numerical escape hatch.
D. Indication scope is broad across LSDs but anchored to ataxia outcomes
The disease list is wide, but the outcome anchor is ataxia measurement (SARA). That suggests the patentee is capturing LSD phenotypes where cerebellar/ataxia features are clinically tracked on SARA and can improve under acetyl-leucine therapy.
How strong is the enforceability position implied by the claim architecture?
The patent’s enforceability posture (based on claim drafting mechanics) is strengthened by three design features:
1) Duration + endpoint combo: “at least about 3 months” plus a quantified or qualitative clinical endpoint.
2) Outcome-anchoring across multiple scales: SARA plus fSARA, SCAFI, mRDS, NPC-CSS (including 5-domain), and EQ-5D-5L.
3) Stereochemistry and dosing modules: dependent claims create multiple narrower theories of infringement that match different product presentations.
What is not visible from the provided claim text is the full spec’s experimental support, example datasets, and definitions of “therapeutically effective amount,” all of which can matter heavily in claim construction and enablement. Still, the claim text itself shows the patent is built around a clinical effect story.
Claim-by-claim map (condensed)
| Claim no. |
What changes versus the independent base |
| 1-3 |
Treat / Delay / Reverse framing; LSD list; ≥ ~3 months; improved SARA vs baseline |
| 4 |
acetyl-leucine is acetyl-DL-leucine |
| 5 |
enantiomeric excess of L or D |
| 6 |
single enantiomer (L or D) |
| 7 |
single enantiomer is L |
| 8 |
dose 1-15 g/day |
| 9 |
LSD limited to NP-A/B/C |
| 10 |
dose 1-10 g/day for claim 9 subset |
| 11 |
LSD limited to Tay-Sachs, Sandhoff, NP-A, NP-C, MPS-II, MPS-III, GM1 |
| 12 |
at least 1 point SARA improvement |
| 13 |
add assessment options (fSARA, SCAFI, mRDS, NPC-CSS, 5-domain NPC-CSS, EQ-5D-5L) |
| 14 |
delay claim dose 1-15 g/day |
| 15 |
delay claim LSD limited to Tay-Sachs, Sandhoff, NP-A, NP-C, MPS-II, MPS-III, GM1 |
| 16 |
delay claim at least 1 point SARA improvement |
| 17 |
delay claim assessment options list |
| 18 |
reversal claim dose 1-15 g/day |
| 19 |
reversal claim LSD limited to Tay-Sachs, Sandhoff, NP-A, NP-C, MPS-II, MPS-III, GM1 |
| 20 |
reversal claim at least 1 point SARA improvement |
| 21 |
reversal claim assessment options list |
| 22-24 |
NP-C only for treat/delay/reverse |
| 25-27 |
fSARA is the specified assessment (tied to claim 13/17/21) |
US patent landscape: what can be concluded from the provided data alone
No bibliographic identifiers beyond the US Patent number are provided in the prompt (e.g., application/publication number, assignee, filing dates, priority, claim set changes across continuations). Without those, a complete landscape (family members, prosecution history, expiration risks, and citation graph) cannot be derived accurately.
What can be concluded from the claim content alone is the likely landscape pattern from an R&D and competitive planning standpoint:
- This is a clinical-use patent anchored to SARA endpoints in LSDs.
- It has broad disease coverage but still depends on use conditions that map to ataxia measurement.
- It anticipates several dosing and stereochemical variants.
A competent freedom-to-operate approach would treat this as a high relevance “method” risk for any acetyl-leucine program targeting LSDs where clinicians track SARA and where improvements are expected after multi-month therapy.
Key Takeaways
- US 12,433,863 claims acetyl-leucine-based methods for treating, delaying, and reversing progression of defined lysosomal storage disorders, with a fixed ≥ ~3-month administration and an endpoint requirement: improved SARA vs baseline.
- The claim set is reinforced by dependent claims covering acetyl-DL-leucine, enantiomeric variants (L, D, and enantiomeric excess), and dose bands (about 1 to 15 g/day).
- The patent ties infringement to clinical response and supports it with an expanded endpoint bundle: fSARA, SCAFI, mRDS, NPC-CSS (including 5-domain), and EQ-5D-5L, alongside SARA.
- NP-C is explicitly singled out in multiple dependent claims, and the dosing and endpoint modules create multiple enforcement lanes tied to different program designs.
FAQs
1) Is US 12,433,863 a composition-of-matter patent or a method-of-use patent?
It is a method-of-treatment patent, drafted as a method of administering acetyl-leucine to achieve clinical improvements (SARA) in specific LSD indications.
2) What is the minimum treatment duration required by the claims?
The independent treatment and reversal claims require administration for at least about 3 months; the delay claim also uses at least about 3 months as the duration threshold.
3) What endpoint does the patent require?
The independent claims require an improved SARA assessment compared to before administration, with dependent claims adding an option for at least 1 point SARA improvement and/or additional assessment instruments.
4) Does the patent cover both L- and D-forms of acetyl-leucine?
The dependent claims explicitly address enantiomeric excess and single-enantiomer forms, including L as one dependent narrowing option; the enantiomeric framework also references D at least at the “L-enantiomer or D-enantiomer” level.
5) Which dose ranges are specified in the dependent claims?
Dependent claims specify acetyl-leucine regimens of about 1 g to about 15 g per day, with a narrower about 1 g to about 10 g per day in at least one NP-A/B/C subset.
References (cited sources)
No external sources were used or cited because the prompt did not include bibliographic or factual material beyond the claim text provided.
