United States Patent 6,358,527 (Drug) — Scope, Claim Construction, and U.S. Landscape
US Drug Patent 6,358,527 (granted Apr 9, 2002) covers a specific formulation and method: a fast-dissolving galanthamine hydrobromide (reported as 1:1) tablet used to treat dementia (including Alzheimer’s dementia), mania, and nicotine dependence, where the carrier/diluent is a spray-dried mixture of lactose monohydrate and microcrystalline cellulose (75:25) and the solid system includes an insoluble or poorly soluble cross-linked polymer disintegrant. The patent also claims a manufacturing method defined by dry blending and compression in the dry state using that composition.
What do the claims actually cover?
H2: How broad is Claim 1?
Claim 1 is a method-of-treatment claim with product feature limitations. It has four key requirement blocks:
1) Indication scope (treatment target)
- “a disorder selected from dementia, mania or nicotine dependence”
2) Active ingredient
- “a therapeutically effective amount of galanthamine hydrobromide (1:1)”
3) Dosage form + administration
- “administering to the patient a tablet”
4) Tablet formulation constraints (carrier/disintegrant/diluent)
- “pharmaceutically acceptable carrier”
- carrier comprises:
- “a spray-dried mixture of **lactose monohydrate and microcrystalline cellulose (75:25) as a diluent”
- “and an insoluble or poorly soluble cross-linked polymer disintegrant”
Practical claim construction impact
- The claim is broad on indications (three disorders) but narrow on dose form composition because it hard-codes the carrier composition and requires the specific diluent type (spray-dried lactose monohydrate/MCC 75:25) plus a cross-linked polymer disintegrant that is insoluble or poorly soluble.
H2: Are dependent claims meaningful for scope?
- Claim 2: dementia (narrows from claim 1)
- Claim 3: Alzheimer’s dementia (narrows further)
- Claims 4 and 5: mania and nicotine dependence (depend on claim 1, narrowing the selected disorder)
These dependent claims primarily confirm that the applicant intended separate infringement positions for each disorder within the claim 1 set. The formulation constraints remain identical across all dependent claims.
H2: What does Claim 6 add?
Claim 6 is a product-by-process claim for a “fast-dissolving” tablet of galanthamine hydrobromide (1:1). It binds infringement to both:
- what the tablet is made from (specific solids and diluent),
- and how it is made (dry blending, optional lubricant mixing, dry-state compression, optional film coating).
Claim 6 requires:
1) Dry blending of:
- active: galanthamine hydrobromide (1:1)
- disintegrant: “insoluble or poorly soluble cross-linked polymer disintegrant”
- optional glidant
- diluent: “spray-dried mixture of lactose monohydrate and microcrystalline cellulose (75:25)”
2) Optional lubricant mixing
3) Compression in dry state into a tablet
4) Optional film coating
Practical claim construction impact
- Claim 6 can be used either as a direct infringement theory or as leverage in litigation around manufacturing steps, where generic developers sometimes change processing to reduce risk (but must still match the diluent/disintegrant requirement).
Claim-by-claim scope map (infringement elements)
| Claim |
Type |
Core elements |
What must be true for infringement |
| 1 |
Method of treating |
Dementia / mania / nicotine dependence + tablet + galanthamine hydrobromide (1:1) + pharmaceutically acceptable carrier |
Must practice treatment and administer a tablet whose carrier includes (a) spray-dried lactose monohydrate/MCC 75:25 and (b) an insoluble or poorly soluble cross-linked polymer disintegrant |
| 2 |
Dependent |
Dementia |
Same formulation + treatment targets “dementia” |
| 3 |
Dependent |
Alzheimer’s dementia |
Same formulation + treatment targets “Alzheimer’s dementia” |
| 4 |
Dependent |
Mania |
Same formulation + treatment targets “mania” |
| 5 |
Dependent |
Nicotine dependence |
Same formulation + treatment targets “nicotine dependence” |
| 6 |
Product-by-process |
Fast-dissolving galanthamine HBr (1:1) tablet made by dry blending, optional lubricant, dry-state compression, optional film coating |
Tablet must be made by the claimed process using the claimed solids (including the spray-dried lactose/MCC 75:25 diluent and cross-linked polymer disintegrant) |
What is the likely “sweet spot” of protection?
H2: The protected technical core
The most decision-relevant limitation across claim 1 and claim 6 is the tablet solid-state system:
- Diluents/carrier: spray-dried lactose monohydrate + microcrystalline cellulose in 75:25 ratio
- Disintegrant system: an insoluble or poorly soluble cross-linked polymer disintegrant
- Dosage form characterization: “fast-dissolving” tablet (explicit in claim 6)
- Processing: dry blending and dry-state compression
For market entrants, the risk profile concentrates on products that:
- use spray-dried lactose monohydrate/MCC 75:25, and
- pair that diluent with a cross-linked polymer disintegrant that is insoluble or poorly soluble,
- and are manufactured by dry blending + compression (at least as recited in claim 6).
H2: How an entrant could design around (scope-reduction logic)
The claim’s internal structure gives multiple theoretical carve-outs, but only those that actually change the claim-critical elements matter:
- Change the diluent system: not spray-dried lactose monohydrate/MCC 75:25
- Change the disintegrant type: use a disintegrant that is not “cross-linked polymer” or not “insoluble/poorly soluble”
- Change the manufacturing process: use a route that does not map to the claimed “dry blending” + optional lubricant mixing + “compressing … in the dry state” pattern (while still producing a tablet)
This patent is not a general “any fast-dissolving galanthamine tablet” barrier. It is anchored to the specific diluent specification plus the polymer disintegrant attribute, and to the dry route compression described in claim 6.
Patent landscape in the U.S.: how to frame the surrounding risk
H2: Category map around 6,358,527
Based on what is claimed, the relevant U.S. landscape divides into three practical buckets:
1) Formulation patents for galanthamine fast-dissolving tablets
- Look for patents claiming:
- fast-dissolving or orally disintegrating tablets for galanthamine,
- specific diluent systems,
- and disintegrant selection (especially cross-linked polymer disintegrants).
2) Manufacturing/process patents
- Dry blending, direct compression, disintegrant mixing, optional glidants/lubricants, and coating steps are typical process claim targets.
3) Method-of-treatment patents for dementia, mania, nicotine dependence
- Claim 1’s method-of-treatment elements are only protective if the tablet administered also includes the claimed carrier composition.
- But the “indication” breadth can still matter when method claims are litigated against a specific formulation or brand.
H2: Where 6,358,527 fits among claim types
- The patent combines indication method coverage (claims 1-5) with formulation/product-by-process coverage (claim 6).
- That mix matters for freedom-to-operate because formulators can encounter:
- a formulation barrier (cannot use the claimed tablet),
- and a method barrier (even if a similar formulation is practiced off-label).
H2: What other U.S. patents are likely to be “close” (based on claim features)
Even without listing each external document here, the “nearest neighbor” claims in a typical U.S. landscape would share at least one of these features:
- galanthamine hydrobromide fast-dissolving/ODT tablets
- use of lactose and/or microcrystalline cellulose in fixed ratios
- spray-dried lactose/MCC excipient systems
- cross-linked polymer disintegrants (often classified by chemistry such as sodium starch glycolate-type or cross-linked povidone-type categories, though the claim does not name a brand)
- direct compression route or dry compression route
- optional lubricant and optional glidant and optional film coating steps
From an enforcement perspective, claim 6 is a strong hook for discovery into manufacturing controls (batch records, blending recipes, disintegrant sourcing, excipient processing).
Scope: what is explicitly inside vs outside the claims
H2: Inside the claims
Claim 1 requires a tablet where the carrier includes both:
- spray-dried mixture of lactose monohydrate and microcrystalline cellulose (75:25) as a diluent
- an insoluble or poorly soluble cross-linked polymer disintegrant
Claim 6 requires the tablet to be made by:
- dry blending the active + disintegrant (+ optional glidant) + the spray-dried lactose/MCC 75:25 diluent
- optionally add lubricant
- compress in the dry state
- optionally film-coat
H2: Outside the claims
A tablet likely falls outside if any of the following are not met:
- diluent is not that spray-dried lactose monohydrate/MCC 75:25 system
- disintegrant is not a cross-linked polymer or is not insoluble/poorly soluble
- tablet is not produced by the stated dry blending + dry-state compression route for claim 6
- the dosage form is not a tablet for claim 1
Evidence-grade elements for diligence and litigation readiness
H2: Technical diligence checklist aligned to the claims
For a candidate product or competitor’s product, claim coverage reduces to verifiable parameters:
- Excipients
- Does the formulation include lactose monohydrate + MCC in 75:25?
- Is that mixture spray-dried (not merely physical blending)?
- Disintegrant
- Is the disintegrant a cross-linked polymer?
- Is it characterized as insoluble or poorly soluble?
- Process
- Is the product made by dry blending the solids and direct compression in the dry state?
- Are lubricants used (optional in claim 6, but process mapping matters)?
- Dosage form
- Is it actually administered as a tablet and described as fast-dissolving for the product line aligned to claim 6?
H2: How the claims can be asserted
- Against a manufacturer (claim 6): by comparing manufacturing route and composition lineage to the claimed recipe and process.
- Against an end-user prescriber/practitioner (claim 1): via method-of-treatment where the administered tablet matches the carrier requirements.
Key Takeaways
- US 6,358,527 protects a galanthamine hydrobromide (1:1) fast-dissolving tablet used for dementia, mania, and nicotine dependence.
- The strongest technical limiter across both method and product-by-process claims is the carrier/diluent specification: spray-dried lactose monohydrate and microcrystalline cellulose at 75:25, plus an insoluble or poorly soluble cross-linked polymer disintegrant.
- Claim 6 adds a process hook: dry blending and dry-state compression, with optional glidant, lubricant, and film coating.
- For landscape work, the most relevant “adjacent” patents are those targeting ODT/fast-dissolving galanthamine formulations with specific excipient processing (spray-dried lactose/MCC) and cross-linked polymer disintegrants, and those covering direct compression routes.
FAQs
1) Does 6,358,527 cover any galanthamine fast-dissolving tablet?
No. It requires a tablet whose carrier includes a spray-dried lactose monohydrate/MCC 75:25 diluent and an insoluble/poorly soluble cross-linked polymer disintegrant.
2) Are Alzheimer’s dementia treatments covered separately?
Yes. Claim 3 narrows claim 2 to “Alzheimer’s dementia,” but it keeps the same formulation requirements from claim 1.
3) Is the “spray-dried” feature essential?
Yes. Both claim 1 (carrier comprises) and claim 6 (diluent comprising) specify the spray-dried mixture of lactose monohydrate and microcrystalline cellulose (75:25).
4) What disintegrant types fall under the claim?
The claim requires an insoluble or poorly soluble cross-linked polymer disintegrant. Disintegrants that do not meet both attributes likely fall outside.
5) Can a process change avoid claim 6 while keeping the same formulation?
Claim 6 is product-by-process, so changing the manufacturing steps could reduce mapping to the claimed “dry blending” and “dry-state compression” route, but infringement still depends on whether the final tablet and its composition requirements match the claims.
References
[1] United States Patent 6,358,527.
