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Title: Benzoyl peroxide
compositions having increased potency
United States Patent: 7,326,420
Issued: February 5, 2008
Inventors: Burkhart; Craig
G. (Toledo, OH), Burkhart; Craig N. (Toledo, OH)
Appl. No.: 10/917,240
Filed: August 12, 2004
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Woodbury College's
Master of Science in Law
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Abstract
A benzoyl peroxide composition having
increased potency includes benzoyl peroxide, a tertiary amine and/or a
transition metal, and a base that increases radicals formed by the
peroxide.
Description of the
Invention
BACKGROUND OF THE INVENTION
This invention relates in general to methods of treating skin conditions
such as acne, and in particular to methods of increasing the efficacy of
peroxides such as benzoyl peroxide in the treatment of skin conditions.
The pathophysiology of acne vulgaris, the most common cutaneous disease,
is the consequence of the interplay of follicular hyperkeratinization,
bacteria in the follicular canal, and sebum production. The exact
mechanism triggering the development of the comedone and the stimuli
causing the non-inflamed lesion to become provoked are poorly understood.
The microbiology of acne vulgaris and its immunologic ramifications
constitute a major thrust of present research in the elucidation of the
pathogenesis of inflammatory acne. Within the microbial flora of the
pilosebaceous unit, P. acnes is the most meaningful organism in acne
causation.
The methods of acne therapy are usually grouped into several categories
such as keratolytics, antibacterials, sebosuppressives, and hormones.
Benzoyl peroxide (BP) is the most widely used topical agent for acne since
its introduction in the 1960's. BP is very effective for the treatment of
acne because it is antibacterial, functions as a peeling agent, has
comedolytic activity, and reduces free fatty acid levels. Concomitant
topical treatment of BP and erythromycin is stated to be superior to BP
alone. However, no synergistic activity has been found with this
combination. Instead, such combination therapies are hypothesized to gain
their efficacy by the coupled action of two effective treatments.
SUMMARY OF THE INVENTION
This invention relates to methods of increasing the efficacy of peroxides
such as benzoyl peroxide in the treatment of skin conditions such as acne.
In a preferred embodiment, the invention relates to methods of increasing
radicals formed by peroxides on/in the skin, more specifically near/in the
comedone, for topical use in dermatology.
In a specific embodiment, the invention relates to the use of transitional
metals such as Cu(1) and ferrous ions to increase the efficacy of
peroxides such as benzoyl peroxide.
In another embodiment, the invention relates to a method by which a
peroxide such as benzoyl peroxide and its activator (or adjunctive agent)
are added to the skin surface at the same time (and not days or months
before). This ensures that the ingredients are not inactivated or lost
strength by being placed together prior to usage.
In another embodiment, the invention relates to the use of a more soluble
form of peroxide such as benzoyl peroxide to increase its efficacy.
In another embodiment, the invention relates to the addition of a side
chain to a peroxide such as benzoyl peroxide so that it is activated by
light.
In a further embodiment, the invention relates to the addition of a
tertiary amine to a peroxide such as benzoyl peroxide at the time of skin
application, to improve the efficacy of the peroxide. This could include
any tertiary amine structure except for an erythromycin structure.
In another embodiment, the invention relates to the addition of dapsone or
other material to a peroxide such as benzoyl peroxide to improve its
efficacy.
Various advantages of this invention will become apparent to those skilled
in the art from the following detailed description of the preferred
embodiments.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention relates to methods of increasing the efficacy of peroxides
such as benzoyl peroxide in the treatment of skin conditions such as acne.
In a preferred embodiment, the invention relates to methods of increasing
radicals formed by peroxides on/in the skin, more specifically near/in the
comedone (but not limited thereto), for topical use in dermatology. The
methods use the radicals formed by peroxides such as benzoyl peroxide,
optimizing conditions such that the skin/comedone is the only place they
are formed as opposed to in a storage container or wherever the benzoyl
peroxide happens to be from the time of application to when the benzoyl
peroxide breaks down into its radicals or is metabolized).
The methods of the invention may use the principles of photodynamic
therapy directed at acne. Instead of forming radicals in cancer cells, the
methods form radicals in/by the comedone (skin surface, sebum within P.
acnes). Location and timing of formation of radicals is a very important
part of the methods.
The methods use the assumption that radicals derived from BP or other
peroxides are the most useful in acne therapy (as opposed to reactive
oxygen intermediates used in photodynamic therapy).
In a specific embodiment, the invention relates to the use of transitional
metals such as Cu(1) and ferrous ions to increase the efficacy of
peroxides such as benzoyl peroxide. The use of transitional metals such as
Cu(1) and ferrous ions (as alluded to in the text) to increase the
efficacy of benzoyl peroxide. It is anticipated that such an addition to
benzoyl peroxide would increase the generation of benzoyloxyl radicals.
The transitional metals include all the elements between Group IIA and
IIIa in the periodic table. The list includes zinc, cadmium, mercury,
scandium, titanium, vanadium, chromium, manganese, yttrium, zirconium,
niobium, molybdenum, technetium, ruthenium, rhodium, palladium, silver,
lanthanum, hafnium, tantalum, tungsten, rhenium, osmium, iridium,
platinum, gold, mercury, actinium, unnilquadium, unnilpentium, unnilhexium,
and uniseptium.
A few characteristics of transitional metals include: most are harder and
more brittle with higher melting points, boiling points, and heats of
vaporization than the non-transitional metals. their ions and compounds
are usually colored. they form many complex ions. most exhibit multiple
oxidation states. many of them are paramagnetic, as are many of their
compounds. many of the metals and associated compounds are effective
catalysts.
In another embodiment, the invention relates to a method by which a
peroxide such as benzoyl peroxide and its activator (or adjunctive agent)
are added to the skin surface at the same time (and not days or months
before). An example of such would be a better package system in which the
various ingredients that would be added to benzoyl peroxide would be put
into a dispenser with two or three chamber (depending upon the number of
items combined) to separate the product's ingredients so they do not
interact until the instant you apply them to one's acne. This separation
would ensure that the ingredients are not inactivated or lost strength by
being placed together prior to usage.
Another example of such a system would be benzoyl peroxide (bp) dissolved
in a hydrophobic solvent and the activator in a polar solvent. The BP and
activator wouldn't meet until applied onto the skin surface. Lipophilic
carriers are well known in the art. For an example of the activator in a
hydrophilic solvent, both protic and aprotic solvents are included. Protic
solvents such as methanol, ethanol, formamide, N-methylformamide, and
water, a hydrogen is attached to the electronegative part of the reagent.
The hydrogen has a proton-like character and strongly reacts with anionic
nucleophiles. Aprotic solvents do not contain positively polarized
hydrogens. These include acetone, acetonnitrile, N,N-dimethylformamide,
DMSO, hexamaethylphophoric triamide--the aprotic solvents increase the
reactivity of nucleophiles in SN2 reactions (the possible mechanism of
radical formation by the BP tertiary amine combination).
Retin A micro is an example of a product released by a polymer. The retin
A is stored in a small polymer bead. After application of these beads onto
the skin, retin A slowly diffuses out of the polymer and into the skin.
The invention would have the activator of benzoyl peroxide radical
formation contained in a similar polymer. The activator would be slowly
released (by diffusion or breakdown of the polymer) into the skin allowing
it to react with BP. Alternatively, the BP could be stored in and released
from the polymer. Or, both the activator and BP could be released from
their own individual polymers to react when the meet (in the environment
of the skin/comedone).
In another embodiment, the invention relates to the use of a more soluble
form of peroxide such as benzoyl peroxide to increase its efficacy. The
use of a more soluble form of benzoyl peroxide. The present-day products
actually use benzoyl peroxide in the form of crystals. We are able to
solubilize benzoyl peroxide either by altering its hydric solvents, or by
adding a side chain to its structure.
In another embodiment, the invention relates to the addition of a side
chain to a peroxide such as benzoyl peroxide so that it is activated by
light. We could also add a side chain to benzoyl peroxide so that it is
activated by light.
In a further embodiment, the invention relates to the addition of a
tertiary amine to a peroxide such as benzoyl peroxide at the time of skin
application, to improve the efficacy of the peroxide. This could include
any tertiary amine structure except for an erythromycin structure. We
believe that benzoyl peroxide efficacy can be improved by adding a
tertiary amine at the time of skin application. Therefore, we would be
including all substances (and chemicals) which have a tertiary amine
within the provisional patent, be they antibiotics or whatever. The
invention would include all tertiary amine structures, save for the
erythromycin structure that is presently used in a commercial product
named benzymycin.
Some nonlimiting examples of tertiary amines include Alfuzosin,
Alimemazine, Analgesic drug (Reference 97), Atropine, alpha,alpha-bis
[3-(N-benzyl-N-methyl-carbamoyl)-piperidino]-p-xylene dihydrobromide,
Bupivacaine, cis-trans-Cavinton, Cloperastine, Cyamemeazine,
Cyclopentolate,
2-(4,5-dihydro-1H-imidazol-2-yl)-2-propyl-1,2,3,4-tetrahydropyrrolo]3,2,1-
-hi[-indole, 1-decyl-3-(N,N-diethylcarbamoyl) piperidine hydrobromide,
Diltiazem, Dimethindene, Diperodone, Disopyramide, Disopyamide,
semipreparative, Dixyrazine, Doxazosin, Dropropizine, Hydroxychloroquine
and metabolites, Ketoconazole, Laudanosine, Marcaine, Medetomidine,
Mepivacaine, Mepivacaine (micro column), Meptazinol, Methadon, Nefopam,
Nicotine, Omeprazole, Oxybutynin, Oxyphencyclimide, Pheniramine, 3-PPP,
Procyclidine, Promethazine, Proxyphylline, Remoxipride, Tetrahydrozoline,
Tetramisole, Tetramisole (micro column), Thioridazine ring-sulphoxide,
Tolperisone, Trihexyphenidyl, Trimipramine, Tropicamide, Vamicamide,
Verapamil, and Vinca alcaloids. The structures and other characteristics
of these tertiary amines can be found on the internet at www.chromtech.se/tertiary.htm.
The listed amines are all drugs, but the methods of the invention are not
limited to just drugs--any tertiary amine would work.
Along with transition metals, tertiary amines potentiate radical formation
by BP. A possible mechanism involves reaction of the amine and BP by a
S.sub.N2 mechanism. The intermediate thus formed thermally decomposes to
benzoyloxy radicals and an amine radical cation. The benzoyloxy radicals
may further decompose into phenyl radicals. All of these radicals can
react with biological molecules possibly causing some biological effect.
In another embodiment, the invention relates to the addition of dapsone to
a peroxide such as benzoyl peroxide to improve its efficacy. Heme is a
protoporphyrin. P. acnes actually produces protoporphyrins.
5-aminolevulinic acid (ALA) increases protoporphyrin production by P.
acnes. ALA is the same stuff used in photodynamic chemotherapy and
photodynamic antimicrobial chemotherapy. Methylene blue, toluidine blue O,
phthalocyanine, and haematoporphyrin derivative could also be used.
Phenothiazinium dyes could also be used. These materials might work by
depleting the antioxidant levels in/around the comedone allowing the BP
derived radicals to reach the comedone or spread further throughout the
comedone.
Viagra (sildenafil) increases NO production by blood vessels (and maybe
the skin). It is an example of a molecule inducing the skin to produce a
benzoyl peroxide activator.
Claim 1 of 20 Claims
1. A method of treating a bodily
condition comprising topically applying to the body of a human or animal a
combination of a peroxide and a tertiary amine, the tertiary amine
increasing radicals formed by the peroxide on the body to thereby increase
the efficacy of the peroxide in the treatment of the condition, and
increasing the potency of the peroxide by at least one of the following
steps: (a) combining the peroxide with a material that further increases
radicals formed by the peroxide; (b) mixing the peroxide and the tertiary
amine after they have been applied to the body; (c) energizing reaction of
the peroxide with the tertiary amine on the body; (d) treating the body
with an oral or topical anti-oxidant; (e) increasing penetration of the
peroxide through a surface of the body; and (f) heating at least one of
the peroxide and the tertiary amine before applying them to the body. ____________________________________________
If you want to learn more
about this patent, please go directly to the U.S.
Patent and Trademark Office Web site to access the full
patent.
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