United States Patent 8,067,033 (Ibuprofen + Famotidine Rapid, Non-Enteric, Low Sulfamide, Low Contact Surface Area): Scope, Claims, and US Landscape
United States Patent 8,067,033 claims a two-compartment oral pharmaceutical composition that combines ibuprofen (800 mg) with famotidine (26.6 mg) for three-times-per-day (TID) dosing, with rapid, synchronous release of both APIs, no enteric coating and no sustained or delayed-release formulation, a cap on ibuprofen-famotidine direct contact surface area (<= 130 mm²), and storage stability limits tied to sulfamide formation (<= ~1% sulfamide after 1 month at 40°C/75% RH).
The claim set is structured as a core independent claim (claim 1) with layering/structure dependent claims (claims 2-10, 15, 16) and release kinetics and stability dependent claims (claims 11-14). The resulting scope is narrow in formulation structure (contact area, barrier separation) and performance (rapid release and tight release timing), while also carving out key product design variants (enteric-coated and delayed/sustained systems; famotidine as beads dispersed in an ibuprofen matrix).
What does claim 1 actually require? (Independent claim scope)
Claim 1: required elements (all must be met)
Claim 1 requires a single composition with the following features:
Dose and components
- A pharmaceutical composition comprising:
- First portion containing 800 mg ibuprofen
- Second portion containing 26.6 mg famotidine
Contact area limitation
- The surface area of direct physical contact between ibuprofen and famotidine does not exceed 130 mm².
Impurities / stability constraint
- When stored at 40°C and 75% relative humidity for one month, no more than about 1% sulfamide is present.
Release profile
- The composition is formulated so that release of both ibuprofen and famotidine occurs rapidly at about the same time.
- Neither the composition nor either API is:
- enterically coated, or
- formulated for sustained or delayed release.
Indication / use
- The composition is “for use” according to a TID administration schedule to reduce the risk of developing ibuprofen-induced ulcers in a human patient requiring ibuprofen for an ibuprofen-responsive condition.
Key practical meaning
- The product must be non-enteric immediate-type with fast dissolution and similar timing for both APIs.
- The formulation must prevent unacceptable ibuprofen-famotidine interaction (measured via direct contact area and sulfamide formation under stressed storage).
- The “about the same time” language is reinforced by dependent kinetic claims (claims 11-12), tightening enforcement leverage.
What structural variations are covered by dependent claims? (Claims 2–10, 15–16)
Separation and architecture
Claim 2
- The second portion is not in direct physical contact with the first portion.
Claim 15
- The first portion completely surrounds the second portion.
This supports a design where ibuprofen forms an outer compartment around a famotidine-containing core.
Famotidine as beads, with barrier layers
Claim 3
- The second portion comprises a layer of famotidine beads.
Claim 4
- Each famotidine bead is coated with a barrier layer.
This adds a micro-barrier around bead particles even if macroscopic compartments are close.
Core-shell or dual-layer barrier constructions
Claim 5
- A famotidine core with an ibuprofen shell that completely surrounds the core, with a barrier layer interposed between compartments.
Claim 6
- The core is substantially spherical.
Claim 7
- The core is substantially cylindrical.
Claim 8
- Second portion has a layer of famotidine, first portion has a layer of ibuprofen, separated by a barrier layer.
Barrier thickness ranges
Claim 9
- Barrier layer thickness from 20 to 3,000 microns.
Claim 10
- Barrier layer thickness from about 25 to 250 microns.
This narrows the likely preferred embodiments and increases claim strength against very thin or very thick barriers.
Express exclusion of a specific mixing architecture
Claim 16
- Famotidine is not present as famotidine beads dispersed in an ibuprofen matrix.
This is a clear negative limitation aimed at one common formulation approach (beads mixed throughout an ibuprofen-containing matrix).
What performance requirements tighten the claim? (Claims 11–14)
These dependent claims convert the broad “rapid and about the same time” language into measurable dissolution outcomes and storage retention thresholds.
Dissolution extent within 30 minutes
Claim 11
- At least 80% of famotidine and at least 80% of ibuprofen are released into solution within 30 minutes at pH ~6.8 to 7.4.
Relative timing of release onset
Claim 12
- Release of famotidine begins within 5 minutes of the beginning of release of ibuprofen.
Stability / retention under room conditions
Claim 13
- After 9 months at 25°C/60% RH:
- at least 95% of both ibuprofen and famotidine each are present.
Claim 14
- After 9 months at 25°C/60% RH:
- at least 98% of both ibuprofen and famotidine each are present.
These thresholds strengthen enforceability by tying infringement to both release and storage integrity.
How the claim set maps to product designs (infringement-relevant design matrix)
Below is a practical mapping of claim elements to formulation patterns.
| Design feature |
Where covered |
Claim hooks |
| Two-compartment or layered structure separating famotidine from ibuprofen |
Broadly claim 1; dependent claims 2, 5, 8, 15 |
“direct physical contact <=130 mm²”, “barrier layer interposed” |
| No enteric coating and no sustained/delayed release |
Claim 1 (negative limitation) |
“none … enterically coated or … sustained or delayed release” |
| Rapid synchronous release |
Claim 1; tightened by 11-12 |
>=80% released by 30 min; famotidine onset within 5 min of ibuprofen |
| Barrier layer thickness ranges |
Claims 9-10 |
20–3,000 microns; 25–250 microns (narrow band) |
| Barrier around beads |
Claims 3-4 |
famotidine beads each coated with barrier |
| Core-shell geometry |
Claims 5-7, 15 |
spherical or cylindrical core fully surrounded by ibuprofen with interposed barrier |
| Avoid mixed matrix beads |
Claim 16 |
famotidine beads dispersed in ibuprofen matrix excluded |
| Storage impurity control (sulfamide) |
Claim 1 |
<= ~1% sulfamide after 40°C/75% RH for 1 month |
| Storage API retention |
Claims 13-14 |
>=95% or >=98% of each API after 9 months at 25°C/60% RH |
| TID ulcer risk reduction use |
Claim 1 |
use for reducing ibuprofen-induced ulcers with TID schedule |
What is the likely center of gravity for enforcement? (Most vulnerable and most defensible claim subsets)
Most vulnerable: systems that meet all “hard” constraints
To land inside claim 1, a product must simultaneously satisfy:
- dose levels (800 mg ibuprofen + 26.6 mg famotidine),
- non-enteric immediate-type release,
- synchronized rapid dissolution (strengthened by claims 11-12),
- low direct contact surface area (<=130 mm²) and/or physical separation (claim 2),
- sulfamide suppression under stress (<=~1% after one month at 40°C/75% RH).
Most defensible: products engineered around barrier + compartment geometry
The dependent claims (3-10, 15) give additional coverage for:
- barrier thickness bands (20–3,000; 25–250 microns),
- specific shapes (spherical/cylindrical),
- barrier-coated beads.
Clear off-ramp: enteric and delayed/sustained products
Because claim 1 expressly excludes enteric-coated and sustained/delayed-release formulations, an otherwise similar dual-API combo that uses enteric protection or delayed release timing is structurally pushed outside claim 1’s negative limitations.
Clear off-ramp: bead dispersion inside an ibuprofen matrix
Claim 16 directly targets a common formulation style: beads dispersed in a matrix.
US patent landscape analysis: where 8,067,033 sits and what it likely blocks
The landscape around 8,067,033 is driven by two competitive axes:
- Clinical regimen and pairing: ibuprofen + acid-suppressant for ulcer risk reduction.
- Formulation strategy: compartmentalized or barrier-separated immediate-release designs that control ibuprofen-famotidine interaction (impurities) while matching release timing.
1) Competitors likely at risk: dual-API immediate-release with compartment barrier architecture
Patents and products that match the same fundamental goals (ibuprofen ulcer protection via famotidine with rapid non-enteric release) will be evaluated against the distinctive engineering constraints in claim 1:
- direct contact area cap,
- sulfamide impurity formation under stress,
- synchronous release timing.
2) Competitors less exposed: enteric-coated / delayed-release combos
Any formulation that uses:
- enteric coatings, or
- sustained/delayed-release approaches,
will not satisfy claim 1’s negative limitations by design.
3) Competitors less exposed: simple co-milled mixtures or matrix blends
A blended tablet where ibuprofen and famotidine are co-located at high contact area is unlikely to meet:
- the <=130 mm² direct contact surface area requirement,
- the sulfamide limit.
4) Design-around focus: avoid sulfamide formation triggers
The sulfamide threshold is a strong “functional” barrier to design-around. Even if a product uses separation, it must still show that at 40°C/75% RH for one month sulfamide does not exceed ~1%.
5) Design-around focus: decouple release timing
If a competitor decouples famotidine and ibuprofen release onset beyond the within 5 minutes requirement, it may avoid claim 12. But claim 1 still requires “rapid” and “about the same time” release, so decoupling may still be challenged depending on dissolution profile evidence.
Claim-by-claim threat summary (what each claim adds to infringement arguments)
Independent claim 1
- Defines the full infringement gate: composition, contact area, sulfamide, non-enteric rapid synchronous release, and TID ulcer-risk reduction use.
Claims 2 and 15
- Add explicit physical separation and “outer ibuprofen surrounds inner famotidine” geometry.
Claims 3-4
- Add a specific internal famotidine format: bead layer with barrier-coated beads.
Claims 5-8
- Provide alternative structural embodiments:
- core-shell with interposed barrier,
- spherical/cylindrical core,
- layered dual-compartment separated by barrier.
Claims 9-10
- Provide measurable barrier thickness constraints, supporting manufacturing infringement mapping.
Claims 11-12
- Provide dissolution kinetics targets (extent at 30 minutes; onset alignment within 5 minutes).
Claims 13-14
- Provide stability targets over 9 months at 25°C/60% RH.
Claim 16
- Provides a negative limitation that blocks a bead-in-matrix dispersion approach.
Key Takeaways
- US 8,067,033 is centered on a barrier-separated immediate-release ibuprofen + famotidine composition with rapid, synchronous dissolution, non-enteric / non-delayed release, and tight impurity and stability controls.
- The independent claim 1’s enforceability hinges on three measurable pillars: (1) direct contact surface area <=130 mm², (2) sulfamide <= ~1% after 1 month at 40°C/75% RH, and (3) rapid release with release onset alignment (tightened by claims 11-12).
- Dependent claims broaden embodiments into bead layers, core-shell tablets, layered compartments, and barrier thickness ranges, while excluding enteric/delayed-release systems and famotidine beads dispersed in an ibuprofen matrix.
FAQs
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Does the patent cover enterically coated ibuprofen-famotidine combinations?
No. Claim 1 expressly requires that neither the composition nor the famotidine nor the ibuprofen is enterically coated and that the formulation is not sustained or delayed release.
-
What is the key physical constraint controlling drug-drug interaction?
The surface area of direct physical contact between ibuprofen and famotidine does not exceed 130 mm².
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What impurity limit is used to define acceptable shelf stability?
Claim 1 limits sulfamide to no more than about 1% after 1 month at 40°C and 75% RH.
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What dissolution performance is required?
At pH ~6.8 to 7.4, at least 80% of each API releases into solution within 30 minutes (claim 11), with famotidine release onset within 5 minutes of ibuprofen (claim 12).
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Are famotidine beads dispersed in an ibuprofen matrix covered?
No. Claim 16 excludes formulations where famotidine is not present as famotidine beads dispersed in an ibuprofen matrix.
References
[1] United States Patent US 8,067,033. “Pharmaceutical composition comprising ibuprofen and famotidine.” (Claims text provided in prompt).
