United States Patent 8,026,284: Claim Scope and Patent Landscape for Enterically Enhanced Cysteamine/Cystamine Delivery
What does US 8,026,284 claim?
US 8,026,284 is directed to methods of administering cysteamine or cystamine (and pharmaceutically acceptable salts) using a formulation strategy that increases delivery to the small intestine. The claims emphasize enteric-coating functionality, dose/frequency parameters, and therapeutic positioning across cystinosis and broader disease categories (including neurodegenerative and hepato-protectant use).
Core claim architecture (independent claims)
The independent claims you provided define two main inventive concepts:
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Twice-daily dosing with small-intestine delivery increase
- Claim 1: Administer cysteamine/cystamine (or salts) by administering a composition that increases delivery to the small intestine, twice per day.
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Enteric-coated formulation to increase small-intestine delivery
- Claim 4: Administer a composition that has an enteric coating providing increased delivery to the small intestine.
Independent claims also extend the delivery concept with:
- Reduced dosing frequency (< four times daily) (Claim 10)
- Increased time to Cmax vs non-enteric formulation (Claim 11)
Dependent claim scope: dose, site, coating chemistries, and release trigger
The dependent claims tightly map formulation and physiological outcomes.
Dosing parameters
- Dose per administration
- Claim 2: 0.5 to 1.0 g/m² per dose
- Claim 3: 0.7 to 0.8 g/m² per dose
- Total daily dose
- Claim 12: about 1.35 g/m²/day
- Frequency constraint
- Claim 10: frequency less than four times daily
Site-of-action targeting in the GI tract
The claims specify anatomical regions and physiological triggers:
- Claim 13: increased delivery to proximal or mid-small intestine (or both)
- Claim 14: delivery to duodenum, jejunum, or mid-ileum
- Claim 15: release when reaching a GI region where pH > 4.5
- Claim 6: enteric coating releases cysteamine/cystamine derivative when the composition reaches the small intestine or pH > 4.5
Enteric coating composition (specific polymer list)
Claims 5 and 25 set the coating selection from defined polymers/material classes. The claim language is essentially a closed list (as written), including:
- Polymerized gelatin
- Shellac
- Methacrylic acid copolymer type CNF
- Cellulose phthalates / derivatives:
- cellulose butyrate phthalate
- cellulose hydrogen phthalate
- cellulose proprionate phthalate
- cellulose acetate phthalate (CAP)
- cellulose acetate trimellitate (CAT)
- hydroxypropyl methylcellulose phthalate
- hydroxypropyl methylcellulose acetate
- Cellulose hydrogen phthalate variants and related derivatives:
- hydroxypropyl methylcellulose acetate succinate (HPMCAS)
- dioxypropyl methylcellulose succinate
- carboxymethyl ethylcellulose (CMEC)
- hydroxypropyl methylcellulose acetate succinate (HPMCAS)
- Polyvinyl acetate phthalate (PVAP)
- Acrylic acid polymers/copolymers from methyl/ethyl acrylate/methacrylate structures with acrylic/methacrylic acid ester copolymers
Claim 24/25 anchor the enteric coating requirement as an element “of the method.”
Pharmacodynamic and exposure-related outcomes
- Time to Cmax:
- Claim 11: enteric formulation provides increased time to Cmax vs non-enterically formulated cysteamine/cystamine.
- Gastric acid effects:
- Claim 26: gastric acid levels decreased compared to non-coated cysteamine.
- Biomarker effect:
- Claim 27: induces significant reduction in leukocyte cystine levels vs non-coated cysteamine.
How broad is the method claim scope across diseases?
US 8,026,284 is not limited to cystinosis. It includes broad therapeutic method claims where the enterically coated cysteamine/cystamine is used for:
- Cystinosis (Claim 7; also Claim 16 narrows method of any one of Claims 1 or 10 to cystinosis)
- Neurodegenerative disease (Claim 8; Claim 17 narrows any one of Claims 1 or 10 to neurodegenerative disease)
- Specific neurodegenerative diseases:
- Claim 18: Huntington’s disease or Parkinson’s disease
- Hepato-protectant agent positioning (Claim 9)
- Metabolic disorder (Claim 20)
- Free radical damage (Claim 21)
The breadth creates a formulation-to-indication portability: the “enteric delivery to the small intestine” is constant while the therapeutic context changes.
What does the claim set say about combinations with other therapeutics?
US 8,026,284 includes explicit dependent claims adding a second agent:
- Claim 19: if cystinosis, further treating with a second therapeutic agent
- Claim 22: for neurodegenerative disease, further treating with a second agent
- Claim 23: for Huntington’s/Parkinson’s, further treating with a second agent
These add-on claims are important for competitive strategies that pair enteric cysteamine with other standard-of-care drugs.
What is the likely protective “center of gravity” of infringement?
From a freedom-to-operate perspective, enforcement risk concentrates on the delivery mechanism and formulation-defined features:
- Enteric-coating requirement (Claims 4, 6, 24-26)
- Release condition tied to small intestine or pH > 4.5 (Claims 6, 15)
- Evidence-linked outcomes:
- time-to-Cmax shift (Claim 11)
- cystine biomarker reduction (Claim 27)
- Dose and frequency envelope:
- 0.5-1.0 g/m² and 0.7-0.8 g/m² per dose (Claims 2-3)
- total daily dose about 1.35 g/m²/day (Claim 12)
- less than four times daily (Claim 10)
Practical claim mapping (how a product would land)
A competing product can potentially avoid literal infringement by deviating on any required element. The claims are not a single-parameter concept; they require combinations like:
- method + cysteamine/cystamine + enteric coating + small intestine delivery increase; plus in some claims, dose/frequency and coating polymer identity.
How does the claims text constrain design-around?
Because the claims include both functional and enumerated coating materials, design-around strategies usually require at least one axis of change:
- Avoid the enumerated enteric polymers list (where a claim depends on “coating selected from the group consisting of …”)
- Change the GI release trigger so it is not tied to reaching small intestine/pH > 4.5 as claimed
- Avoid the exposure shift requirement in Claim 11 (time to Cmax increased vs non-enteric)
- Avoid the dose/frequency envelope if targeting the dependent claim set (Claims 2-3, 10, 12)
What does the patent landscape look like relative to US 8,026,284?
A full “landscape” requires the bibliographic data, prosecution history, priority chain, expiration, claim construction events, and citations/forward citations. Your prompt provides only the claim text. Without patent publication metadata and citation graphs, a complete and accurate landscape cannot be produced.
Accordingly, only the internal landscape implied by US 8,026,284 can be described here: it covers enterically coated cysteamine/cystamine formulations intended to shift delivery/exposure to the small intestine and treat cystinosis plus broader disease areas.
Key Takeaways
- US 8,026,284 is centered on increasing delivery of cysteamine/cystamine to the small intestine, primarily via enteric coating that releases at pH > 4.5.
- The independent claim set includes both: twice-daily administration with increased small-intestinal delivery and enteric-coated compositions delivering to the small intestine.
- The dependent claims add enforceable granularity: dose range (0.5-1.0 g/m²; preferred 0.7-0.8 g/m²), total daily dose (~1.35 g/m²/day), frequency (<4/day), anatomic targets (duodenum/jejunum/mid-ileum), and exposure biometrics (increased time to Cmax) plus cystine/leukocyte biomarker reduction.
- The claims extend beyond cystinosis to neurodegenerative disease (Huntington’s/Parkinson’s), hepato-protectant use, metabolic disorders, and free-radical damage, with optional add-on therapy dependent claims.
FAQs
1) Is the enteric coating required for all claims?
No. Claims 1 and 10 focus on increased delivery to the small intestine and dosing frequency, while Claims 4 and 24-25 explicitly require an enteric coating.
2) What pH threshold is used in the claims?
The coating is described as releasing when reaching a GI region where pH is greater than 4.5 (Claims 6 and 15).
3) What dosing frequency limit is claimed?
Claim 10 requires frequency less than four times daily.
4) Which neurodegenerative diseases are named?
Huntington’s disease and Parkinson’s disease (Claim 18).
5) Does the claim set include biomarker outcomes?
Yes. Claim 27 requires a significant reduction in leukocyte cystine levels compared to non-coated cysteamine.
References (APA)
No external sources were provided or cited in the prompt; therefore, no APA references can be listed.
