United States Patent 4,855,290 (US4855290): Scope of Claims and Patent Landscape
What does US4855290 actually claim?
US4855290 claims a chemical entity defined by a Markush formula (labeled “formula (I)”), its stereochemical variants, and acid addition salts, plus pharmaceutical compositions and treatment methods in the central nervous system (CNS), including Alzheimer’s-type senile dementia. The claims are structured into: (i) compound coverage (claims 1-16, with a specific compound called out in claim 67), (ii) pharmaceutical compositions (claims 17-29 and 51-66), and (iii) methods of treatment and dosing/route (claims 30-50 and 57-66).
Core compound claim: claim 1 (Markush scope)
Claim 1 covers:
- A compound of formula (I) and geometrical isomers, enantiomers, diastereoisomers, racemates, and acid addition salts.
- R1 is selected from:
- hydrogen
- lower alkyl
- cyclopentyl
- cyclohexyl
- phenyl
- diphenylmethylol
- lower alkyl substituted by one or two phenyl groups
- R (as written in the claim) is selected from:
- lower alkyl
- cyclopentyl
- cyclohexyl
- phenyl
- diphenylmethylol
- lower alkyl substituted by one or two phenyl groups
Claim effect: broad chemical genus with stereochemical and salt forms captured under the same claim framework.
Dependent claim narrowing: claims 2-11
Claims 2-11 set specific selections for R1 and R2-like variables (the claim text mixes “R1” and “R2” naming, but the intent is consistent: fixing the substituent choices within the Markush). Examples:
- Claim 2: R1 is hydrogen; R2 is one of lower alkyl / cyclopentyl / cyclohexyl / phenyl / diphenylmethylol / lower alkyl substituted with one or two phenyls.
- Claim 5: R1 hydrogen and R2 methyl.
- Claim 6: R1 hydrogen and R2 phenyl.
- Claim 7: R1 hydrogen and R2 diphenylmethyl.
- Claim 8: R1 hydrogen and R2 in {ethyl, propyl, diphenylmethylol}.
- Claim 9: R1 methyl and R2 phenyl.
- Claim 10: R2 phenyl and R1 in {ethyl, cyclohexyl}.
- Claim 11: R1 and R2 each phenyl.
Claim effect: layered coverage from genus (claim 1) to specific disclosed embodiments (claims 5-11).
Stereochemical and salt sub-range: claims 12-16
Claims 12-16 narrow to geometrical isomers of the specific embodiment in claim 5 (R1 hydrogen, R2 methyl) and describe hydrochloride salts with different melting points:
- Claim 12: cis-isomer hydrochloride has the relatively lower melting point.
- Claim 13: trans-isomer hydrochloride has the relatively higher melting point.
- Claim 14: the hydrochloride salt of claim 5 compound (without cis/trans limitation).
- Claim 15: cis-isomer hydrochloride (explicit “relatively lower melting-point”).
- Claim 16: trans-isomer hydrochloride (explicit “relatively higher melting-point”).
Claim effect: material-grade differentiation via stereochemistry and salt form tied to physical property language (melting points).
Specific compound called out: claim 67
Claim 67 identifies the compound as:
- “3-hydroxy-3-mercaptomethyl quinuclidine.”
Claim effect: this anchors at least one concrete species to the broader genus.
What is the commercial/strategic scope of the compound coverage?
US4855290 uses a typical CNS small-molecule Markush strategy: a single core scaffold with substituent variability at two positions (R1 and R/R2-like substituent). The claim set is designed to:
- capture a family of stereochemically and salt-manufacturable embodiments under the same scaffold definition,
- monetize downstream formulation and route of administration (oral, parenteral, rectal, insufflation, transdermal),
- capture indication-driven method-of-use positions (CNS diseases broadly, then Alzheimer’s-type dementia),
- secure dosing ranges (mg/kg and mg per unit dosage form) that are easy to map to clinical or compounding regimens.
How broad are the pharmaceutical composition claims?
Genus composition: claim 17
Claim 17 covers:
- A pharmaceutical composition comprising a compound of formula (I) according to claim 1 or its pharmaceutically compatible acid addition salt,
- together with an inert carrier or diluent.
Route and dosage form: claims 18-20
- Claim 18: form suitable for oral, rectal, parenteral, insufflation.
- Claim 19: transdermal administration form.
- Claim 20: unit dosage form.
Transdermal formulation specificity: claim 21
- Transdermal composition with the compound (formula I, claim 1 or salt) and a low molecular weight fatty acid.
More restrictive sub-genus formulations: claims 22-29
- Claim 22: R1 phenyl; R2 in {ethyl, cyclohexyl, phenyl}.
- Claim 23: R equals hydrogen; R2 in {methyl, ethyl}.
- Claim 24: compound defined in claim 12 (cis-isomer hydrochloride of the claim 5 embodiment).
- Claim 25: claim 24 plus optional co-actives from a specified list (see below).
- Claims 26-29: wider selection constraints within the formula (including R2 being certain groups like lower alkyl (>=3 carbons), cyclopentyl, cyclohexyl, phenyl, diphenylmethylol, and lower alkyl substituted by phenyl; and R1 being similar set), plus specific example embodiments:
- Claim 27: R1 ethyl and R2 phenyl.
- Claim 28: R1 hydrogen and R2 diphenylmethyl.
- Claim 29: R1 hydrogen and R2 in {propyl, phenyl, diphenylmethylol}.
Combination add-on list appears repeatedly
Across claims 25, 54, 60, 65, and 65-like structures, the coadministerable list includes:
- physostigmine
- tetrahydroaminoacridine
- choline
- lecithin
- piracetam
- aniracetam
- pramiracetam
- oxiracetam
- 4-aminopyridine
- 3,4-diaminopyridine
- somatostatin
Claim effect: combination therapy is protected when paired with specific formula I embodiments, especially the Alzheimer’s-linked cis-hydrochloride species (via claim 24 and claim 25).
Unit dose concentration: claims 51-53
- Claim 51: unit dosage form with formula (I) compound (claim 1 species or salt) in 0.5 to 500 mg plus inert carrier.
- Claim 52: 5 to 100 mg.
- Claim 53: 10 to 50 mg.
Additional route-labeled dosage: claims 55-56
- Claim 55: adapted for oral.
- Claim 56: adapted for parenteral.
How broad are the method-of-use claims?
Broad CNS treatment
- Claim 30: treat CNS diseases in mammals by administering formula (I) compound of claim 1 or salt.
- Claim 31: treat CNS diseases in mammals using composition of claim 17.
- Claim 32: transdermal administration of claim 1 compound or salt for CNS diseases.
Cholinergic system deficiency (broad to specific)
- Claim 33: treat diseases due to deficiency in central cholinergic system by administering the compound of claim 2 (R1 hydrogen; R2 in the claim 2 set) including stereoisomers/salts.
- Claim 34: same with composition of claim 17.
- Claim 35: same via transdermal administration.
Cholinergic hyperfunction (broad and route)
- Claim 36-38: treat cholinergic hyperfunction using formula (I) compounds where R2 is limited to {lower alkyl (>=3 carbons), cyclopentyl, cyclohexyl, phenyl, diphenylmethylol, lower alkyl substituted with one or two phenyl groups} and R1 is limited similarly; and includes (a) direct administration, (b) administration via composition with carrier, (c) transdermal administration.
- Claims 39-44: narrower embodiments using claim 7 and claim 9, including transdermal.
Alzheimer’s-type senile dementia (core commercial target)
- Claim 45: treat senile dementia of Alzheimer’s type using claim 13 compound (cis/trans described earlier; claim 13 is tied to trans-isomer hydrochloride higher melting point of claim 5 embodiment).
- Claim 46: same using composition of claim 12 (cis-isomer hydrochloride).
- Claim 47: transdermal administration of claim 12 compound.
- Claims 48-50 and 60-66: coadministration with the listed co-actives and dosing ranges for oral and parenteral delivery.
What dosing and administration ranges are claimed for Alzheimer’s?
Oral dosing: claims 57-59
-
Claim 57: oral administration of compound of claim 12 (cis-isomer) or salt at 0.1 to 60 mg/kg.
-
Claim 58: 0.5 to 10 mg/kg.
-
Claim 59: 1 to 5 mg/kg.
-
Claim 60: includes coadministered actives from the list.
-
Claim 61: dosing via unit dosage form (0.5 to 500 mg in the unit) with actives already used in claim 60 context.
Parenteral dosing: claims 62-64
-
Claim 62: parenteral administration of compound of claim 12 or salt at 0.01 to 40 mg/kg.
-
Claim 63: 0.05 to 5 mg/kg.
-
Claim 64: 0.1 to 2 mg/kg.
-
Claim 65: coadministered actives from the list.
-
Claim 66: unit dosage form (0.5 to 500 mg unit) structure.
Claim effect: the patent claims a dosing envelope that could read on label-like regimens if a later developer chooses to align clinical dosing with these ranges, especially in combination with the specific co-therapies.
How does US4855290 map to a patent landscape view?
A practical landscape read from the claim architecture:
- Chemical genus claims (claim 1 and dependent claim 2/3/4 plus 5-11) are designed to block generic or follow-on scaffold makers from “inventing around” by using closely related substituents within the Markush.
- Stereoisomer/salt differentiation (cis/trans hydrochloride with melting-point language) supports a separate enforcement axis against manufacturing changes that might try to select a different stereochemical form.
- Composition and route coverage is extensive. A product formulating for oral/parenteral/rectal/insufflation or transdermal (with a fatty acid excipient) can fall into the same patent family’s claim set.
- Indication and method-of-use coverage extends beyond Alzheimer’s:
- generic CNS diseases,
- central cholinergic deficiency,
- cholinergic hyperfunction.
- Combination therapy is explicitly claimed with a defined list of known CNS and cholinergic agents, which can constrain partnering strategies (for example, avoiding coadministration with any member of the list in the claimed context).
Landscape implications for competitors and investors
- A company pursuing a next-generation quinuclidine/quinuclidinol-like scaffold in CNS should treat US4855290 as a scaffold-locking patent for formula (I) with the two-position substituent variability and the stereochemical/salt variants.
- A company pursuing reformulation, alternate route, or co-therapy should treat US4855290 as a formulation and regimen-locking patent, because it claims not only the active but also administration route and dosing ranges for Alzheimer’s-type senile dementia.
Key claim scope table (high-level)
| Claim block |
Coverage focus |
What gets locked in |
| Claims 1-11 |
Markush genus of formula (I) + stereoisomers + salts |
Substituent options for R1 and R/R2 and broad stereochemical capture |
| Claims 12-16 |
cis/trans hydrochloride of the claim 5 species with melting-point language |
Different stereochemical and salt forms for the same substitution pattern |
| Claim 17-29 |
Pharmaceutical compositions with inert carrier and route options |
Oral/parenteral/rectal/insufflation/transdermal with fatty-acid excipient; sub-genus selections |
| Claims 30-44 |
CNS disease and cholinergic deficiency/hyperfunction treatment |
Indication-specific method-of-use and route variants |
| Claims 45-50 |
Alzheimer’s-type senile dementia treatment with cis/trans linkages |
Indication-specific method-of-use built around the hydrochloride isomers |
| Claims 51-66 |
Unit dosage and mg/mg/kg dosing ranges plus combination co-therapy |
Practical dosing envelopes for oral and parenteral use; coadmin list tied to those regimens |
| Claim 67 |
Specific compound identity |
A concrete species anchor to the claimed chemical matter |
Key Takeaways
- US4855290 is built to enforce across three layers: chemical genus (formula I with R1/R substituent Markush), formulation/route (oral/parenteral and transdermal with fatty acid excipient), and method-of-use (broad CNS then cholinergic deficiency/hyperfunction, then Alzheimer’s-type senile dementia).
- The patent’s tightest enforcement lever for commercial CNS programs is Alzheimer’s-type senile dementia, where it claims cis-hydrochloride-linked treatment with explicit oral and parenteral dosing ranges and combination coadministerable agents.
- Stereochemistry is not peripheral. The patent differentiates cis and trans hydrochloride isomers using “relatively lower/higher melting-point” language and then ties at least some composition and method claims to those isomeric forms.
- For follow-on developers, “inventing around” is constrained because the Markush language keeps the genus broad while dependent claims and co-therapy lists cover multiple practical product strategies.
FAQs
1) Does US4855290 claim only one molecule?
No. It claims a formula (I) genus with variable substituents (R1 and R/R2-like positions), plus stereoisomers/enantiomers/diastomeric forms and acid addition salts, with specific dependent claims selecting particular substituent combinations.
2) Are salt forms covered?
Yes. The claims include “acid addition salts” generally, and also specific hydrochloride cis/trans variants tied to melting-point language for the claim 5 embodiment.
3) Does the patent cover transdermal administration?
Yes. It claims transdermal compositions and transdermal methods, including a transdermal composition claim that requires a low molecular weight fatty acid.
4) Is Alzheimer’s-type senile dementia the only indication?
No. The patent also claims methods for CNS diseases broadly and for diseases due to central cholinergic deficiency and cholinergic hyperfunction.
5) Does the patent restrict combination therapy?
Yes. It claims coadministration with a defined list of CNS and cholinergic agents, tied to Alzheimer’s-type senile dementia regimens.
References
[1] United States Patent 4,855,290. “United States Drug Patent 4,855,290.” Claims and claim text as provided in the prompt.
