US Patent 7,465,465: Scope of Claims, Claim-Element Mapping, and US Patent Landscape
US Drug Patent 7,465,465 is directed to lanthanum carbonate formulations (notably as chewable tablets and also powders) for delivering defined amounts of elemental lanthanum with specified excipient systems and a dry (no wet granulation or drying) processing route using compression/roller compaction and milling to yield free-flowing intermediates. The independent claim is structured around (i) composition ranges expressed as elemental lanthanum wt%, (ii) excipient wt% ranges (diluent and flow agent), (iii) a process without wet granulation or drying, and (iv) specific diluent and flow agent lists. Dependent claims then narrow hydration form and specific formulations for chronic renal insufficiency.
What is the effective claim scope (what must be present for infringement)?
The scope is constrained by a conjunction of composition limits + excipient selection + processing steps + “no wet granulation or drying.” A product or process that misses any required element in the independent claim is outside that independent claim’s literal scope.
Claim 1: Core independent scope (chewable tablet)
Product: lanthanum carbonate pharmaceutical formulation in a chewable tablet
Lanthanum carbonate amount: 200 mg to 1000 mg elemental lanthanum per dose
Lanthanum concentration: 10 to 40 wt% elemental lanthanum in the formulation (as elemental lanthanum)
Excipients:
- Diluent: 40 to 80 wt% of the formulation; selected from a defined list (see below)
- Flow agent: 0.1 to 5.0 wt%; selected from a defined list (see below)
Process: produced by a process comprising:
- (a) either blending lanthanum carbonate + excipients to form a mixture, or
- (b) blending lanthanum carbonate + excipients, then compressing into a slug or roller compacting into a strand, then milling into a free flowing mixture
- then compressing the mixture into a tablet
Process limitation: performed without wet granulation or drying
Allowed diluents (in the independent claim text) include:
dextrates, corn syrup, oligosaccharide, isomaltooligosaccharide, glucose, lycasin, xylitol, lactitol, erythritol, mannitol, isomaltoligosaccharide, polydextrose, dextrin, starch, fructose, maltodextrin, maltitol, isomalt, lactose, sorbitol, microcrystalline cellulose, sucrose based diluent-binders, confectioner’s sugar, calcium sulfate dihydrate, calcium lactate trihydrate, hydrolysed starches, dextrose, inositol, hydrolyzed cereal solids, amylase, glycine.
Allowed flow agents include:
magnesium stearate, talc, polyethylene glycol, silica, colloidal anhydrous silica, hydrogenated vegetable oils, glyceryl behenate, glyceryl monostearate.
Claim 2: Same core composition and ranges, but different process sequence
Claim 2 keeps the same composition and excipient selection, but requires:
- compressing the lanthanum carbonate into a slug or roller compacting into a strand
- milling into free flowing material
- blending with excipients
- compressing into a tablet
- still without wet granulation or drying
- still the same diluent/flow agent lists
Claims 3-6: Narrowing sub-ranges and ingredient species
- Claim 3: lanthanum carbonate is La₂(CO₃)₃·xH₂O with x = 3 to 8
- Claim 4: further narrows x = 4 to 5
- Claim 5: diluent is dextrates or sorbitol
- Claim 6: flow agent is colloidal anhydrous silica at about 2 wt%
Claims 7-8: Specific example formulations (chronic renal insufficiency)
These claims lock in explicit weight percentages and hydration water content (about 4 moles).
- Claim 7 formulation:
- lanthanum carbonate 26.5%
- dextrates 69.3%
- colloidal anhydrous silica 2.0%
- talc 1.7%
- magnesium stearate 0.5%
- hydration: water content about 4 moles
- indication text: “treatment of chronic renal insufficiency”
- Claim 8 formulation:
- lanthanum carbonate 45.8%
- dextrates 51.2%
- colloidal anhydrous silica 2.0%
- magnesium stearate 1.0%
- hydration: water content about 4 moles
- indication text: “treatment of chronic renal insufficiency”
These are “hard” claim anchors: they are infringed only by matching those ingredient proportions and hydration attributes (at least as literally claimed).
Claims 9-10: Powder formulations with the same composition/excipient/process backbone
- Claim 9: lanthanum carbonate powder with the same elemental lanthanum amount (200 mg to 1000 mg) and wt% (10 to 40 wt%), same diluent (40 to 80 wt%) and flow agent (0.1 to 5.0 wt%) and lists, and the same dry/no-wet-granulation/no-drying route with slug or roller compacting + milling; ends with a free-flowing powder mixture.
- Claim 10: powder variant using compress lanthanum carbonate into slug/strand, mill, then blend powder with excipients (no tablet compression step).
Claim 11: Alternate minimal process embodiment
Claim 11 is effectively a simplified path: blend lanthanum carbonate and excipients to form a mixture and then compress into a tablet, still in the scope of Claim 1’s overall formulation features (by reference).
Claim 12: Further narrowing lanthanum concentration
- lanthanum carbonate is 20 to 30 wt% lanthanum “as the element”.
How is claim scope partitioned: composition, formulation form, and manufacturing route?
The patent uses three independent axes that each create “gates” against design-around.
1) Dose/elemental lanthanum and concentration
- Dose range: 200 mg to 1000 mg elemental lanthanum
- Concentration range: 10 to 40 wt% elemental lanthanum in the formulation
This is a key lock because it is expressed as elemental lanthanum not merely lanthanum carbonate mass.
2) Excipients as selected lists with wt% ranges
- Diluent: 40 to 80 wt% from a broad list (sugars, sugar alcohols, dextrates, starches, microcrystalline cellulose, certain salts, enzyme/amylase, glycine)
- Flow agent: 0.1 to 5.0 wt% from a small list concentrated on lubricants and silica
If an accused formulation uses a diluent outside the enumerated list (even if it has similar functionality), it can fall outside literal scope for the diluent element.
3) Process: dry processing with specific compaction and milling
The claim explicitly forbids:
and permits/uses:
- blending
- compression into slug or roller compaction into strand
- milling into free-flowing mixture
- tablet compression (for tablet claims)
This matters for both process infringement and design-around: a manufacturer that uses wet granulation or drying cannot literally satisfy the independent claims as drafted, even if composition and excipient identities match.
Claim-element mapping table (what to test in freedom-to-operate)
| Claim element |
Literal requirement in 7,465,465 |
Practical FTO check |
| Dosage amount |
200 mg to 1000 mg elemental La |
Verify label/dose strength and conversion from lanthanum carbonate mass |
| Elemental La concentration |
10 to 40 wt% elemental La in formulation |
Confirm formulation composition basis (wt% elemental La) |
| Dosage form |
Chewable tablet (Claims 1,2,11,12) or powder (Claims 9,10) |
Match dosage form claim category |
| Diluent wt% |
40 to 80 wt% |
Confirm diluent fraction |
| Diluent identity |
Must be one of enumerated diluents |
Compare excipient list to accused product formulation |
| Flow agent wt% |
0.1 to 5.0 wt% |
Confirm lubricant/silica fraction |
| Flow agent identity |
Must be one of enumerated flow agents |
Compare processing-lubricant agent |
| Processing route |
Dry processing, no wet granulation or drying |
Review manufacturing process records |
| Compaction/milling |
Option set (blend only or compact/roller compact + milling) |
Identify whether slug/strand and milling steps occur |
| Hydration form |
Only if dependent claims are asserted: La₂(CO₃)₃·xH₂O; x 3-8 or 4-5 |
Determine hydration water content/control specs |
Where the claim is most vulnerable to design-around (and where it is strongest)
Most difficult to design around
- No wet granulation or drying: If the manufacturing process uses wet granulation or drying, literal claim 1/2/9/10 is avoided regardless of excipient identity.
- Elemental lanthanum concentration range: The 10 to 40 wt% elemental La bracket and 200 to 1000 mg elemental La dose range restrict alternate loading strategies.
Most straightforward to design around (composition-focused)
- Diluent selection list: The diluent must be within the explicitly enumerated list to satisfy the claim. Switching to a diluent binder outside the list can avoid literal infringement.
- Flow agent selection list: Changing lubricant/flow agent outside the enumerated list creates literal non-infringement for the flow agent element.
Secondary strength (dependent claim specificity)
Dependent claims 3-6 and the specific formulation claims 7-8 narrow further with hydration water content, specific diluent species, and specific flow agent identity/amount.
Patent landscape: how US 7,465,465 positions against typical lanthanum carbonate IP
The practical landscape for lanthanum carbonate in the US typically spans:
- drug substance form/manufacture
- oral dosage forms and formulation excipient systems
- manufacturing process improvements
- therapeutic use and dosing regimens
Within that spectrum, US 7,465,465 is best understood as a formulation + dry process patent that targets a particular approach to making chewable or powder products using specific excipient classes and specific dry route constraints.
Key scope characteristics that distinguish it
- It defines formulation ranges in terms of elemental lanthanum delivered per dose and as wt% elemental lanthanum.
- It constrains excipients by both wt% and enumerated identity.
- It contains an explicit manufacturing constraint: no wet granulation or drying, coupled with optional slug/roller compaction and milling into free-flowing mixtures.
- It includes dependent claims around hydration level (La₂(CO₃)₃·xH₂O with x narrowed).
Risk screening framework for other lanthanum products (chewables and powders)
Use this to map accused products/processes to likely risk of falling within the literal scope.
High literal-risk profiles
- Chewable tablet or powder delivering 200-1000 mg elemental La and with formulations containing 10-40 wt% elemental La
- Excipients dominated by enumerated diluents in the 40-80 wt% range and lubricants/flow agents from the 0.1-5.0 wt% enumerated list
- Manufacturing that is dry (no wet granulation and no drying) using compaction (slug/roller compaction) and milling into free-flowing mixtures
Lower literal-risk profiles
- Any process that uses wet granulation or includes drying
- Formulations that use a non-enumerated diluent or flow agent outside the list
- Different dosage form that does not match claim category (tablet vs powder), unless claim amendments or dependent claims are asserted
Operational takeaway: what claim drafting implies for prosecution and enforcement
- Strong process hook: The explicit “without wet granulation or drying” limitation can be decisive in litigation where manufacturing records exist.
- Composition lock-in: Enumerated excipient identity and wt% ranges are designed to narrow the field of alternative formulations.
- Hydration-dependent claims: Control of hydration water content provides a secondary handle for enforcement against specific substance forms (x 3-8; x 4-5).
- Example formulations are tight: Claims 7 and 8 are essentially “formula claims” with explicit percentages and hydration content.
Key Takeaways
- US 7,465,465 claims lanthanum carbonate oral chewable tablets (and powders) with elemental lanthanum dose 200-1000 mg and 10-40 wt% elemental La, built on 40-80 wt% diluent and 0.1-5.0 wt% flow agent from enumerated excipient lists.
- The strongest differentiator is the dry processing limitation: the process is “performed without wet granulation or drying,” and may include slug/roller compaction + milling to free-flowing intermediate prior to final compression (tablets).
- Dependent claims narrow to hydration state (La₂(CO₃)₃·xH₂O; x 3-8 or 4-5), specific diluent species (dextrates or sorbitol), and specific flow agent (colloidal anhydrous silica at ~2 wt%).
- The patent landscape positioning is formulation/process-focused: it targets how the composition is produced and which excipient classes are used, not a broad method of treating renal insufficiency.
FAQs
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Does US 7,465,465 cover wet-granulated lanthanum carbonate tablets?
No. Independent and process-linked claims require the process be performed without wet granulation or drying.
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Is “elemental lanthanum” required for infringement analysis?
Yes. The claim ranges are framed as elemental lanthanum amount per dose and elemental lanthanum wt% in the formulation.
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Can changing the flow agent avoid infringement?
Potentially, if the substituted flow agent is not among the enumerated list and/or falls outside the 0.1-5.0 wt% range.
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Do hydration-state claims matter if the product uses a different hydrate?
For dependent claims 3-4 and the example claims 7-8, hydration matters because the claims specify La₂(CO₃)₃·xH₂O with x ranges and about 4 moles in the examples.
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Is the powder form within scope even if the commercial product is a tablet?
The tablet claims and powder claims are separate claim sets (chewable tablet vs powder), but the shared composition and dry-processing architecture provides a structural basis for related enforcement across product forms.
References
[1] US Patent 7,465,465. (n.d.). Lanthanum carbonate pharmaceutical formulation and process. United States Patent and Trademark Office.
