United States Patent 12,576,054: Scope, Claims, and US Patent Landscape (Vigabatrin RTD Liquid)
US Patent 12,576,054 claims a ready-to-drink (RTD) liquid pharmaceutical composition containing vigabatrin (or a pharmaceutically acceptable salt) with defined preservative, sweetener, flavor, and water conditions, and imposes stability and impurity limits. The claim set is composition-centric, with dependent claims locking down ingredient identities and specific concentration windows, plus packaging and excipient exclusion (buffering agents, antioxidants, solubilizers).
What does US 12,576,054 actually claim?
The independent claim requires an RTD composition that:
- Contains vigabatrin (or pharmaceutically acceptable salt) at 0.1 wt% to 20 wt%
- Contains at least one preservative at 0.001 wt% to 1.0 wt%
- Contains at least one sweetening agent at 0.05 wt% to 40.0 wt%
- Contains at least one flavoring agent at 0.001 wt% to 10.0 wt%
- Uses q.s. purified water
- Is a ready-to-use premixture that does not require reconstitution or dilution prior to administration
- Is stable for at least six months at 2°C to 30°C
- Has total impurities ≤ 0.04 wt%
These elements appear in Claim 1.
It then tightens the scope through dependent claims that:
- Exclude certain excipient classes (Claim 2)
- Limit preservative/sweetener/flavor to specific chemistries and tight numeric windows (Claim 4)
- Fix the main API content to about 10 wt% (Claim 5) and, in a separate “consisting of” claim, locks the full formulation set to named ranges/values (Claim 6)
- Specify an impurity marker (Claim 7 and Claim 14: 5-vinylpyrrolidin-2-one)
- Provide mg/mL-based concentration ranges tied to the same formulation concept (Claim 8), plus single-point concentrations for methylparaben and propylparaben (Claims 9 and 10)
- Specify sucralose as the sweetener and define its concentration (Claims 11 and 12)
- Provide a fully enumerated “consisting of” formulation with named concentrations and stability/impurity requirements (Claim 13)
- Tie flavor specifically to peppermint (Claim 15)
Scope map by claim type
Independent composition claim: breadth with functional limits
Claim 1 drives the broadest coverage. It is a Markush-style formulation scaffold with quantitative ranges for each excipient category plus functional/technical product attributes:
- API range: 0.1–20 wt%
- Preservative range: 0.001–1.0 wt%
- Sweetener range: 0.05–40.0 wt%
- Flavor range: 0.001–10.0 wt%
- Stability: ≥ 6 months at 2°C–30°C
- Total impurities: ≤ 0.04 wt%
- Ready-to-drink: no reconstitution or dilution
Key impact: competitors can potentially design around the claim by (a) changing an excipient class, (b) changing concentration outside the ranges, or (c) failing the stability/impurity thresholds, but typical AND-gating makes “pass-through” hard because the claim requires all conditions.
Dependent exclusions and product form constraints
- Claim 2: the composition is free of buffering agents, antioxidants, and solubilizers. This is a strong formulation restriction and can narrow non-infringing alternatives if their commercial formulation uses any of these excipient functions.
- Claim 3: packaging constraint: packaged in glass, plastic, or metal container. Practically, this is likely broad (covers most pharma containers) but it still ties the claimed composition to conventional container classes.
Narrow “ingredient identity + tight window” claims
Claim 4 specifies:
- Preservatives: methylparaben (0.1125–0.1375 wt%) and propylparaben (0.01125–0.01375 wt%)
- Sweetener: sucralose (0.225–0.275 wt%)
- Flavor: peppermint flavor (0.0027–0.0033 wt%)
This claim is a classic “lock-in”. If a competitor uses different preservative systems, different sweetener, or different flavor (or different concentrations outside the narrow windows), it can evade Claim 4 while still falling under Claim 1 if ranges overlap.
“About 10 wt% vigabatrin” and fully specified formulations
- Claim 5: API at about 10 wt%
- Claim 6 (“consisting of”): sets a specific formulation at about:
- 10 wt% vigabatrin (or salt)
- 0.125 wt% methylparaben
- 0.0125 wt% propylparaben
- 0.25 wt% sucralose
- 0.003 wt% flavor
- q.s. purified water
- Claim 8: expresses the same formulation idea in mg/mL terms:
- 90–100 mg/mL vigabatrin (or salt)
- 1.125–1.375 mg/mL methylparaben
- 0.1125–0.1375 mg/mL propylparaben
- and ranges for sweetener and flavor categories, plus q.s. water
- Claim 9 and 10: “about” fixed single-point-ish concentrations:
- methylparaben about 1.25 mg/mL
- propylparaben about 0.125 mg/mL
- Claim 11 and 12:
- sweetening agent is sucralose
- sucralose at about 0.225–0.275 wt%
- Claim 13 (“consisting of”): enumerates the RTD vigabatrin liquid with:
- 10 wt% vigabatrin (or salt)
- 0.125 wt% methylparaben
- 0.0125 wt% propylparaben
- 0.25 wt% sucralose
- 0.003 wt% flavor
- q.s. purified water
plus stability and impurity limits.
Key impact: “consisting of” language in Claims 6 and 13 strengthens enforceability for that exact ingredient set. It also makes it harder for design-arounds that rely on adding additional excipients, because “consisting of” limits inclusion.
Impurity-anchored claims
- Claim 7: 5-vinylpyrrolidin-2-one is one of the total impurities.
- Claim 14: same impurity condition in the Claim 13 dependent claim.
Key impact: tying a specific impurity to “total impurities” suggests the applicant has test/analytical support that this impurity is present and counted in the total. For enforcement, this can support a narrative that accused products fall within the “total impurities ≤ 0.04 wt%” technical band while also containing that impurity profile.
Flavor specificity
- Claim 15: flavor is peppermint flavor (as dependent on Claim 13).
Claim-by-claim numeric core (where infringement likely concentrates)
Table 1: The formulation constants that recur across the claims
| Component |
Broad Claim 1 Range |
Narrow/locked claims (examples) |
| Vigabatrin (or salt) |
0.1–20 wt% |
About 10 wt% (Claims 5, 6, 8, 13) |
| Total preservative(s) |
0.001–1.0 wt% |
Methylparaben 0.1125–0.1375 wt% and propylparaben 0.01125–0.01375 wt% (Claim 4) |
| Sweetener(s) |
0.05–40 wt% |
Sucralose 0.225–0.275 wt% (Claims 4, 11, 12) and about 0.25 wt% in fixed formulations (Claims 6, 13) |
| Flavoring |
0.001–10 wt% |
Peppermint flavor 0.0027–0.0033 wt% (Claim 4) and about 0.003 wt% flavor in fixed formulations (Claims 6, 13) |
| Total impurities |
≤ 0.04 wt% |
Same condition in independent and several dependents (Claims 1, 13) |
| Stability |
≥ 6 months at 2°C–30°C |
Same conditions in Claim 1 and Claim 13 |
Table 2: “Consisting of” full composition (highest-risk for competitors)
| Claim |
API |
Methylparaben |
Propylparaben |
Sucralose |
Flavor |
Water |
Product attributes |
| 6 |
~10 wt% |
~0.125 wt% |
~0.0125 wt% |
~0.25 wt% |
~0.003 wt% |
q.s. purified water |
RTD no reconstitution/dilution; (stability/impurity in Claim 1 chain) |
| 13 |
10 wt% |
0.125 wt% |
0.0125 wt% |
0.25 wt% |
0.003 wt% |
q.s. purified water |
RTD no reconstitution/dilution; stable ≥ 6 months at 2°C–30°C; total impurities ≤ 0.04 wt% |
What is the practical claim “fence” for competitors?
Likely infringement entry points
- A product that matches the Claim 13 “consisting of” list at the cited concentrations, while meeting RTD, six-month stability at 2°C–30°C, and total impurities ≤ 0.04 wt%.
- A product that matches the Claim 4 ingredient identities and narrow ranges (methylparaben/propylparaben + sucralose + peppermint at tight concentrations), while meeting the RTD and stability/impurity conditions in Claim 1.
- A product matching the broad Claim 1 category ranges even if ingredients differ, so long as the required functional properties (stability and impurity ceiling) are met and formulation does not use buffered/antioxidant/solubilizer excipients where those are needed (Claim 2).
Likely design-around levers (conceptual, based on claim structure)
- Use a different preservative system (or shift preservative outside 0.001–1.0 wt% or outside the methylparaben/propylparaben windows)
- Use a different sweetener (or shift outside 0.05–40 wt% for the category, or outside 0.225–0.275 wt% for sucralose)
- Use non-peppermint flavor or shift flavor concentration outside the cited peppermint windows
- Use a formulation that includes buffering agents, antioxidants, or solubilizers (to break Claim 2)
- Create a product that fails the stability requirement (less than six months at 2°C–30°C) or has total impurities above 0.04 wt%
US patent landscape: what this patent likely covers in the broader system
US 12,576,054 is an RTD formulation patent anchored on a specific API (vigabatrin) and specific excipient system patterns (parabens + sucralose + peppermint) with stability and impurity constraints. In a typical vigabatrin development ecosystem, the patent landscape usually splits into:
- API composition and salt/polymorph space (earlier)
- Manufacturing process patents (often separate)
- Formulation patents for oral liquids including excipient selection, taste masking, palatability, preservative systems, and analytical impurity management
- Patient administration format patents (RTD versus dry powder, reconstitution formats, dosing units, and container closure systems)
Against that backdrop, 12,576,054’s “center of gravity” is the finished dosage form:
- “Ready-to-use premixture” language makes it distinct from two-step or reconstitution systems.
- Six-month stability at 2°C–30°C ties the formulation to packaging/manufacturing suitability and shelf-life performance.
- Total impurities ≤ 0.04 wt% plus impurity identification (5-vinylpyrrolidin-2-one) ties it to analytical impurity control, not just excipient taste and preservative function.
Enforcement posture: what matters for litigation and freedom-to-operate
The highest-value claim set for enforcement
- Claim 13 (and Claim 15) is the cleanest target because it combines:
- A fixed ingredient list (“consisting of”)
- Concrete concentrations (10 wt% vigabatrin; specific paraben/sucralose/flavor levels)
- Performance attributes (RTD; stable ≥ 6 months at 2°C–30°C; total impurities ≤ 0.04 wt%)
The broadest reach, most common dispute zone
- Claim 1 is the broad reach. It creates a scenario where a competitor may argue differences in excipient identity but still faces exposure if their formulation falls within the categorical ranges and meets the stability and impurity thresholds.
Claim 2 as a narrow “exclusion” shield
- If a competitor’s product uses any buffering agents, antioxidants, or solubilizers, they can avoid Claim 2 while still potentially falling under Claim 1. That means Claim 2 can matter both as a defense lever and as an amendment trigger for the patent owner’s theory.
Key Takeaways
- US 12,576,054 covers a ready-to-drink vigabatrin liquid defined by excipient categories, specific ingredient sets, and performance constraints: ≥6 months stability at 2°C–30°C and total impurities ≤0.04 wt%.
- The strongest enforcement claims are Claim 13 (and Claim 15) because they are “consisting of” with a fully enumerated formulation plus stability and impurity performance.
- Claim 4 and Claim 6 narrow to a specific excipient system: methylparaben + propylparaben + sucralose + peppermint with tight numeric windows.
- Claim 2 blocks certain formulation classes by requiring the composition be free of buffering agents, antioxidants, and solubilizers.
- Impurity anchoring appears via 5-vinylpyrrolidin-2-one (Claims 7 and 14), supporting an impurity-based infringement theory tied to the “total impurities” ceiling.
FAQs
1) Which claim is the main infringement risk for a product that matches the core formula?
Claim 13: it is “consisting of” a fixed ingredient list with explicit concentrations plus RTD, stability (≥6 months at 2°C–30°C), and total impurities (≤0.04 wt%).
2) Can a competitor avoid infringement by using a different preservative system?
They may reduce risk against Claims 4, 6, and 13, but they can still fall within Claim 1 if their preservative falls within the broad preservative concentration range and their product still meets the stability and impurity thresholds.
3) Does the patent require the product to be administered without reconstitution?
Yes. Both Claim 1 and Claim 13 require the liquid to be a ready-to-use premixture and not require reconstitution or dilution before administration.
4) How restrictive is the impurity limit?
The claim ceiling is total impurities not more than 0.04 wt%. Claims 7 and 14 further identify 5-vinylpyrrolidin-2-one as one of the total impurities.
5) What excipient classes are excluded in one dependent claim?
Claim 2 requires the composition be free of buffering agents, antioxidants, and solubilizers.
References
[1] United States Patent Application/Patent No. 12,576,054 (claims as provided in the prompt).
