Patent US5034420A successfully refreshed from Google Patents.
US5034420A
Expired / Lapsed
US
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Compositions and method for stabilization of anthralin comprising the addition of an oil soluble antioxidant and an anionic surfactant
Assignee: Bristol Myers Squibb Co
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Filing: 1989-05-17
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Granted: 1991-07-23
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Expires: 2009-05-17
Abstract
Abstract This invention relates to an anthralin composition having improved stability. The invention further relates to a method for increasing the stability of anthralin in dermatological compositions by incorporating therein a stability enhancing amount of an acid stable anionic surfactant and a water soluble antioxidant.
Inventors
- 👤 Jonas C. T. Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:17
CPC Classifications
A; A61; A61K; A61K31/00; A61K31/12; A61K9/00; A61K9/06
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
63 words
In a pharmaceutically acceptable composition suitable for the topical treatment of psoriasis and containing water and anthralin in amounts sufficient to provide an anti-psoriatic effect, the improvement which comprises providing in said composition the stabilizing combination consisting essentially of an oil soluble antioxidant and an acid stable, water soluble anionic surfactant, said combination being present in an amount sufficient to stabilize the anthralin.
Claim 2
Dependent Claim
63 words
In a pharmaceutically acceptable composition suitable for the topical treatment of psoriasis and containing water and anthralin in amounts sufficient to provide an anti-psoriatic effect, the improvement which comprises providing in said composition the stabilizing combination consisting essentially of an oil soluble antioxidant and an acid stable, water soluble anionic surfactant, said combination being present in an amount sufficient to stabilize the anthralin.
Claim 3
Dependent Claim
17 words
The composition according to claim 1 wherein said surfactant is stable at about pH 4 and below.
Claim 4
Dependent Claim
15 words
The composition according to claim 1 wherein said surfactant is stable at about pH 3-4.
Claim 5
Dependent Claim
15 words
The composition according to claim 1 wherein said surfactant is stable at about pH 3.2.
Claim 6
Dependent Claim
57 words
The composition according to claims 2, 3 or 4 further comprising providing said anthralin at a level of about 0.5% by weight to 5.0% by weight and said surfactant is provided in an amount of about 0.05% by weight to about 10% by weight, said percent by weight being based on the entire weight of the composition.
Claim 7
Dependent Claim
56 words
The composition according to claims 2, 3, or 4 further comprising providing said anthralin at a level of about 0.1% by weight to about 3.0% by weight and said surfactant at a level of about 0.1% by weight to about 5.0% by weight, said percent by weight being based on the entire weight of the composition.
Claim 8
Dependent Claim
56 words
The composition according to claims 2, 3, or 4 further comprising providing said anthralin at a level of about 0.5% by weight to about 2.0% by weight and said surfactant at a level of about 0.3% by weight to about 1.0% by weight, said percent by weight being based on the entire weight of the composition.
Claim 9
Dependent Claim
72 words
The composition according to claim 2, 3, or 4 further providing said anthralin at a level of about 0.1% to about 3.0% by weight and said surfactant being selected from the group consisting of alkyl sulfates, alkyl sulfonates, alkyl benzene sulfonates, sulfonyl fatty acids, alkyl phosphates, dioctyl sulfosuccinate, isethionates, alkyl ether sulfates, methyl sarcosines and like non-soap, anionic surfactants, said percent by weight being based on the entire weight of the composition.
Claim 10
Dependent Claim
72 words
The composition according to claims 2, 3, or 4 further comprising providing said anthralin at a level of about 0.5% to about 2.0% by weight and said surfactant being selected from the group consisting of alkyl sulfates, sulfonates, alkyl benzene sulfonates, sulfonyl fatty acids, alkyl phosphates, dioctyl sulfosuccinate, isethionates, alkyl ether sulfate, methyl sarcosines and like non-soap, anionic surfactants, said percent by weight being based on the entire weight of the composition.
Claim 11
Dependent Claim
82 words
The composition according to claims 2, 3, or 4 further comprising providing said anthralin at a level of about 0.1% to 5.0% by weight and said surfactant at a level of about 0.05% to 10.0% by weight and being selected from the group consisting of alkyl sulfates, sulfonates, alkyl benzene sulfonates, sulfonyl fatty acids, alkyl phosphates, dioctyl sulfosuccinate, isethionates, alkyl ether sulfate, methyl sarcosines and like non-soap, anionic surfactants, said percent by weight being based on the entire weight of the composition.
Claim 12
Dependent Claim
82 words
The composition according to claims 2, 3, or 4 further comprising providing said anthralin at a level of about 0.1% to 3.0% by weight and said surfactant at a level of about 0.1% to 5.0% by weight and being selected from the group consisting of alkyl sulfates, sulfonates, alkyl benzene sulfonates, sulfonyl fatty acids, alkyl phosphates, dioctyl sulfosuccinate, isethionates, alkyl ether sulfate, methyl sarcosines and like non-soap, anionic surfactants, said percent by weight being based on the entire weight of the composition.
Claim 13
Dependent Claim
82 words
The composition according to claims 2, 3, or 4 further comprising providing said anthralin at a level of about 0.5% to 2.0% by weight and said surfactant at a level of about 0.3% to 1.0% by weight and being selected from the group consisting of alkyl sulfates, sulfonates, alkyl benzene sulfonates, sulfonyl fatty acids, alkyl phosphates, dioctyl sulfosuccinate, isethionates, alkyl ether sulfate, methyl sarcosines and like non-soap, anionic surfactants, said percent by weight being based on the entire weight of the composition.
Claim 14
Dependent Claim
13 words
The composition according to claim 10 wherein said surfactant is sodium lauryl sulfate.
Claim 15
Dependent Claim
23 words
The composition according to claim 1 wherein said composition is an oil-in-water emulsion and the emulsion contains no antioxidant in the aqueous phase.
Claim 16
Dependent Claim
36 words
The composition according to claim 1 wherein the composition is an oil in water or water in oil emulsion and the oil phase contains an amount of an oil soluble antioxidant sufficient to increase anthralin stability.
Claim 17
Dependent Claim
15 words
The composition according to claim 15 wherein said composition is an oil in water emulsion.
Claim 18
Dependent Claim
26 words
The composition according to claim 15 wherein the composition contains an amount of a water soluble antioxidant in the water phase sufficient to increase anthralin stability.
Claim 19
Dependent Claim
20 words
The composition according to claim 1 wherein said anionic surfactant is a mixture of two or more suitable anionic surfactants.
Claim 20
Independent Claim
37 words
A method for increasing the stability of anthralin containing compositions comprising adding to such compositions a stabilizing effective amount of a combination consisting essentially of an oil soluble antioxidant and an acid stable, water soluble, anionic surfactant.
Claim 21
Independent Claim
37 words
A method for increasing the stability of anthralin containing compositions comprising adding to such compositions a stabilizing effective amount of a combination consisting essentially of an oil soluble antioxidant and an acid stable, water soluble, anionic surfactant.
Claim 22
Dependent Claim
19 words
The method of claim 19 which further comprises adjusting the pH of said compositions to pH 5.3 or below.
Claim 23
Dependent Claim
16 words
The method of claim 19 which further comprises adding a water soluble antioxidant to said composition.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-22 | 1995-01-21 | 1995-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-22 | 1999-01-21 | 1999-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-22 | 2003-01-21 | 2003-07-23 | $7700.00 | Window Closed / Lapsed |