CALCIUM SEQUESTRATION COMPOSITIONS AND METHODS OF TREATING SKIN PIGMENTATION DISORDERS AND CONDITIONS

Information

  • Patent Application
  • 20160030321
  • Publication Number
    20160030321
  • Date Filed
    July 08, 2015
    10 years ago
  • Date Published
    February 04, 2016
    9 years ago
Abstract
The present invention provides compositions containing one or more calcium sequestration agents and methods for topical application of such compositions to the skin to treat skin pigmentation disorders, such as melasma, post-inflammatory hyperpigmentation, pigmentation changes due to skin aging, or any other skin conditions related with normal such as skin of color or abnormal pigmentation such as hypo- or hyper-pigmentation in humans.
Description
FIELD OF THE INVENTION

The invention relates generally to compositions containing one or more calcium sequestration agents and methods for topical application to the skin to treat skin pigmentation disorders, such as melasma, post-inflammatory hyperpigmentation, pigmentation changes due to skin aging, or any other skin conditions related with normal such as skin of color or abnormal pigmentation such as hypo- or hyper-pigmentation in humans.


BACKGROUND OF THE INVENTION

In humans, skin color arises from a complex series of cellular processes that are carried out within a group of cells known as melanocytes. Melanocytes are located in the lower part of the epidermis and their function is to synthesize a pigment, melanin, which protects the body from the damaging effects of ultraviolet radiation. Melanin is a biopolymer originating from conversions of the amino acids phenylalanine or tyrosine.


The mechanism by which the skin pigment melanin is formed (melanin formation=melanogenesis) and skin ultimately gets its color (skin color=skin pigmentation) is a multi-step process and involves the following main steps:

    • 1) Uptake (active transport via transporter) of amino acid precursors (L-tyrosine, L-phenylalanine) into melanocytes promoted by active transport mechanism
    • 2) Conversion (turnover) of phenylalanine into tyrosine catalyzed by enzyme phenylalanine hydroxylase in melanocytes
    • 3) Uptake (active transport via transporter) of amino acid precursors L-tyrosine into melanosmes located in melanocytes promoted by active transport mechanism
    • 4) Conversion (turnover) of L-tyrosine into L-Dopa by enzyme tyrosinase in melanosme
    • 5) Conversion (turnover) of L-Dopa into dopaquinone by enzyme tyrosinase in melanosme
    • 6) Conversion (turnover) of dopaquinone into two different types of melanin called eumelanin (i.e., darker melanin) and phaeomelanin (i.e., lighter melanin) by various biochemical pathways in melanosme. The amount of each type of melanin determines the color and degree of pigmentation in a person's skin
    • 7) Once melanin is produced, transfer of melanosme with melanin from melanocytes to keratinocytes (which are found in the upper layers of the epidermis) via the melanocyte dendrites.


In spite of the fact that the chemical and enzymatic basis of melanogenesis and skin pigmentation are rather well-documented, their regulation at the cellular and biochemical level is only partially understood. For instance, it is well known that the activity of tyrosinase is promoted by the action of alpha-melanocyte stimulating hormone (α-MSH) and UV rays. However, the processes of melanosome maturation and melanosome transfer into the keratinocyte are currently far less studied and not yet understood.


Typically, the more melanin is formed, the darker (or more tanned) the skin. However, melanogenesis and skin pigmentation can be disturbed or disorder, which may lead to undesirable pigmentation patterns. Examples of pigmentation disorders (i.e., disorders where pigmentation is disturbed or disordered) include age spots, liver spots, melasma, hyperpigmentation, etc. This has lead to research to find compounds that will inhibit melanogenesis and reduce skin pigmentation. One of the targets of this research is tyrosinase, the enzyme which catalyses the initial steps in the generation of melanin.


Skin pigmentation has been of concern to human beings for many years. In particular, the ability to remove hyperpigmentation (i.e., areas of darker skin color than the surrounding or adjacent, normal pigmented skin), such as found in age spots, freckles or aging skin generally, is of interest to individuals desiring a uniform skin color, skin complexion, or skin tone. In certain areas of the world, general body whitening is desirable.


There are also hypopigmentation (i.e., areas of less dark skin color than the surrounding or adjacent, normal pigmented skin) and hyperpigmentation disorders that are desirable to treat. Likewise, the ability to generate a tanned appearance without incurring photodamage due to solar radiation is important to many individuals.


Many methods proposed to accomplish depigmentation (i.e., reduction or limitation of skin pigmentation or skin color). For example, arbutin, kojic acid, hydroquinone, retinoids, and other chemical compounds have been used for depigmentation. Chemicals that allow depigmentation of skin are also called skin lighteners, skin brighteners, skin whiteners, skin bleachers or actives with skin lightening, skin brightening, skin whitening or skin bleaching properties.


Many of these previous examples were not acceptable or were of limited efficacy in treating skin pigmentation. Most of these compounds have been described to address only a few steps of the multiple steps leading to melanin formation and ultimately skin pigmentation, which may result their limited efficacy. For instance, most chemicals used for depigmentation are described as inhibitors of tyrosinase. Although tyrosinase production and activity is a key factor in melanin formation, melanogenesis is a multi-step process and involves other important and rate-limiting steps than tyrosinase catalyzed conversion of L-tyrosine and L-Dopa and Dopa-quinone. In addition, many of these compounds have been found to be irritating to the skin and, therefore, undesirable for use. Also, precise application of all these compounds may be necessary in order to achieve the desired result and to avoid distinct line of demarcation between the areas of skin to which such previous compositions have been applied.


Accordingly, there is a need for compositions which inhibit melanogenesis and reduce skin pigmentation by modulating one or more of the multiple steps involved in melanogenesis and skin pigmentation. At the same time, there is also a need for compositions that allow skin depigmentation without irritation. The compositions and methods of the present invention address these long felt needs in the art.


SUMMARY OF THE INVENTION

The present invention provides compositions containing at least one calcium sequestering or calcium binding agent for treating or ameliorating at least one symptom of a skin pigmentation disorder or condition, in a subject in need thereof. Preferably, the calcium sequestering or binding agent is a phosphate. More preferably, the phosphate is glycerophosphoric acid or a, non-calcium, salt thereof. Most preferably, the phosphate is sodium glycerophosphate. The calcium sequestering or binding agent is present in the composition in the amount of about 0.1% to about 25%. When the calcium sequestering or binding agent is phosphate it is preferably present in the composition in the amount of about 1% to about 5% by weight.


The compositions for treating or ameliorating at least one symptom of a skin pigmentation disorder or condition in a subject in need thereof can contain a calcium sequestering or binding agent and can further contain one or more of the following agents, which modulate or regulate at least one step of melanogenesis: L-alanine, glycine, L-isoleucine, L-leucine, hydroquinone, 4-(1-phenylethyl)1,3-benzenediol, arbutin, bearberry leaf extract, kojic acid, oxyresveratrol, gnetol, retinoic acid or retinol, melanosome transfer inhibitor, or α-MSH antagonist.


Also provided are compositions that include at least one additional agent selected from the group consisting of skin moisturization or skin rejuvenation agents. For example, the skin moisturization or skin rejuvenation agents may be ascorbic acid, vitamin E, jojoba oil, shea butter, human fibroblast lysate, retinoic acid, retinol, and/or any derivatives thereof.


The compositions for treating, or ameliorating at least one symptom of, a skin pigmentation disorder or condition, in a subject in need thereof, are formulated for topical administration. By way of non-limiting example, the compositions of the invention can be in the form of a solution, an oil-in-water emulsion, a water-in-oil emulsion, a gel, an ointment, a patch, a paste, a liquid, a foam, a mousse, a spray, an aerosol, a triple emulsion, a nanoemulsion, a microemulsion, a hydrogel, a jelly, a dispersion, a suspension, and/or a tape. The compositions are stable, substantially free of calcium, do not cause an acnegenic/comedogenic response, and/or produce only minor skin irritation upon administration.


Also provided herein are methods of treating or ameliorating a skin pigmentation disorder comprising administering an effective amount of any of the compositions of the invention to a patient suffering therefrom. For example, the skin pigmentation disorder can include, but is not limited to, melasma, post-inflammatory hyperpigmentation, pigmentation changes due to skin aging, age or liver spots, freckles, or any other skin conditions related with normal such as skin of color or abnormal pigmentation such as hypo- or hyper-pigmentation. Preferably, administration of the compound reduces skin pigmentation. The subject can be any mammal, preferably a human.


The invention also provides pharmaceutical formulations containing any of the compositions described herein and at least one pharmaceutically acceptable carrier. Similarly, the invention also provides cosmetic formulations containing any of the compositions described herein an at least one cosmetically acceptable carrier. In other embodiments, the invention provides kits including, in one or more containers, these pharmaceutical or cosmetic formulations. Those skilled in the art will recognize that such kits may optionally contain instructions for use of the pharmaceutical or cosmetic formulations in the treatment or amelioration of said skin pigmentation disorder or condition.


The invention also includes unit dosage forms containing therapeutically effective amounts of any of the compositions and/or pharmaceutical formulations described herein.


Any of the compositions or formulations described herein can be used in methods of reducing skin pigmentation in a patient by administering an effective amount of the composition and/or formulation to the patient. In such methods, the effective amount of the composition is administered topically to the patient.


Also provided are compositions for treating or ameliorating at least one symptom of a skin pigmentation disorder or condition that include 59.68% (by weight) water, 0.1% (by weight) disodium EDTA, 0.3% (by weight) xanthan gum, 0.3% (by weight) chlorphenesisn, 0.6% (by weight) phenoxyethanol, 0.5% (by weight) undecylenoyl phenylalanine, 3.00% (by weight) sodium glycerophosphate, 1.00% (by weight) leucine, 6.00% (by weight) cetearyl alcohol/ceteareth-20, 6.00% (by weight) glyceryl stearate, 3.00% (by weight) diisopropyl adipate, 3.00% (by weight) caprylyl methicone, 1.00% (by weight) dimethicone, 1.00% (by weight) simmondsia chinensis (jojoba) seed oil, 1.00% (by weight) butryospermum parkii shea butter), 0.2% (by weight) DL-alpha tocopheryl acetate, 1.92% (by weight) citric acid 50% solution, 4.00% (by weight) hydroquinone, 0.4% (by weight) sodium metabisulfite, 2.00% (by weight) glycerin, 0.5% (by weight) phenylethyl resorcinol, 0.5% (by weight) aminopropyl ascorbyl phosphate, and 4.00% (by weight) hydroxyethyl acrylate/sodium acryloyldimethyl taurate copolymer isohexadecane polysorbate 60. For example, such a composition can be formulated as a water-in-oil emulsion.


Finally, the invention further provides a composition for treating or ameliorating at least one symptom of a skin pigmentation disorder or condition containing 63.41% (by weight) water, 0.1% (by weight) disodium EDTA, 0.3% (by weight) xanthan gum, 0.3% (by weight) chlorphenesisn, 0.6% (by weight) phenoxyethanol, 0.5% (by weight) undecylenoyl phenylalanine, 3.00% (by weight) sodium glycerophosphate, 1.00% (by weight) leucine, 1.92% (by weight) citric acid 50% solution, 8.25% (by weight) cetearyl alcohol/ceteareth-20, 6.00% (by weight) glyceryl stearate, 5.00% (by weight) diisopropyl adipate, 3.00% (by weight) caprylyl methicone, 1.00% (by weight) dimethicone, 1.00% (by weight) simmondsia chinensis (jojoba) seed oil, 1.00% (by weight) butryospermum parkii shea butter), 0.2% (by weight) DL-alpha tocopheryl acetate, 2.00% (by weight) glycerin, 0.5% (by weight) phenylethyl resorcinol, 0.5% (by weight) aminopropyl ascorbyl phosphate, and 0.42% (by weight) hydroxyethyl acrylate/sodium acryloyldimethyl taurate copolymer/isohexadecane/polysorbate 60. For example, such a composition can be formulated as a water-in-oil emulsion.


Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In the case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.


Other features and advantages of the invention will be apparent from the following detailed description.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a graph showing skin irritation of a composition of the present invention (see Example 3, infra) as compared to other known compositions (e.g.: Compositions A to D), which are not part of this invention. This graph, which represents a “survival” type curve, shows the percentage of subjects who did not show any irritancy reaction reaching an evaluation score of “3” or higher as a function of time (i.e., observation) during the repetitive human irritancy patch test of three weeks (21 days) duration. As judged during this test (by providing “exaggerated” irritation data), the composition of the present invention was better tolerated (i.e., fewer subjects reached an evaluation score of “3” or higher with continued, prolonged application of patch with test material) as compared to Compositions A to D).



FIG. 2 shows the color stability of a composition of the present invention (Composition A) as compared to other, control compositions (e.g.: Compositions B, C and D), which are not part of this invention.



FIG. 3 is a photograph showing the reduction of pigmentation in the skin of a patient using the compounds of the present invention (i.e., the composition described in Example 3, infra). Panel A shows the hyperpigmentation of the patient's skin prior to administration of a compound of the present invention. Panel B shows the reduction in skin pigmentation following 12 weeks of treatment with a composition of the present invention.





DETAILED DESCRIPTION

The present invention is directed to modulating (increasing or decreasing) various steps of melanogenesis (melanin formation) and to reduce skin pigmentation (skin color). More specifically, the present invention provides compositions for treating or ameliorating a symptom of a pigmentation disorder or condition involving a single active agent which modulates more than one step in the multi-step process of melanin formation and skin pigmentation. The present invention also provides compositions which contain at least two active agents (e.g., 2, 3, 4, 5, or more), where each active agent can target at least one step in the multi-step process of melanin formation. These multiple agents decrease melanin formation and skin pigmentation. By targeting multiple steps of melanogenesis and skin pigmentation, the compositions of present invention provide superior properties as compared to hypopigmentation products currently known in the art.


Calcium Sequestration or Binding Agents

Calcium (Ca2+) may be an important regulator of some steps in melanogenesis and skin pigmentation. For instance, increase in calcium is believed to promote active transport of L-phenylalanine and its turnover via phenylalanine hydroxylase to L-tyrosine to significantly increase the pool of this substrate for melanogenesis. (See Dermatol Clin 25, 2007, pp. 283-291). Further, there is some evidence from in vitro studies that calcium impacts the melanosome transfer. (See Pigment Cell Res 20, 2007, pp. 380-384). This study, which used melanocyte-keratinocyte co-cultures, implied that melanin transfer was inhibited when intracellular calcium in keratinocytes was bound (chelated) with calcium chelator 1,2-bis-(o-aminophenoxy)-ethane-N,N,N′,N′-tetraacetic acid tetra-acetoxymethyl ester (BAPTA-AM).


Thus, the present invention provides compositions and methods for skin depigmentation which interferes one or more steps in the melanogenesis and skin pigmentation process where calcium is involved by administering a composition suitable for topical application containing at least one calcium sequestration or binding agent.


Examples of calcium sequestering or binding agents include either inorganic, organic (or a combination thereof, or organo-metallics) derived molecules. Preferably, the agents are calcium-free oxoanions of any or all possible oxidation states, achiral or chiral, selected from phosphates, phosphate esters, phosphonates, phosphonate esters, phosphoramidites, sulfates, sulfate esters, sulfonates, sulfonate esters, sulfites, siloxanes, carbonates, boronates, borinates, borinate esters, siloxanes, siloxane esters, polysiloxanes, sulfoxides, sulfonamides, sulfinic acids, sulfinimides, thiol esters, thioureas, and tosylates. Preferably the organic agents would possess calcium free anionic or neutral Lewis Base donors, achiral or chiral selected from carboxylic acids, polycarboxylates, carboxylic esters, nitriles, isocyanates, hydrazines, hydrazones, ureas, carboxylic esters, oximes, amides, amidines, thioethers, ethers, amines, alcohols, alkoxides, thiols, thiolates.


Table 1 recites non-limiting, representative, examples of carboxylic acids, boronic acids, amines, sulfates suitable to be utilized as calcium sequestration or binding agents














TABLE 1





Product Code & Pack Size
Product Name
CAS
Structure
MF
MW






















AC10430DA   AC10430EA
 1 GR    10 GR
 25.00 USD 189.00 USD
Amino- phenylboronic acid 0.5 ulfate
66472- 86-4


embedded image


C6H8BNO2•0.5 H2O4S
185.98176 (136.94502)












embedded image









AC10702EA   AC10702EE
 10 GR    50 GR
 19.00 USD  42.00 USD
5-bromo- 2-furoic acid
585- 70-6


embedded image


C5H3BrO3
190.98102





AC10728DA   AC10728EA
 1 GR    10 GR
 19.00 USD 102.00 USD
4-bromo- phenylboronic acid
5467- 74-3


embedded image


C6H6BBrO2
200.82644





AC11546EA   AC11546EE
 10 GR    50 GR
 21.00 USD  33.00 USD
3,5- dimethoxy- benzoic acid
1132- 21-4


embedded image


C9H10O4
182.176





AC11968DA
 1 GR
 59.00 USD
2-amino- 3-(5-fluoro- 1H-indol-3- yl)propanoic acid
154-08- 5


embedded image


C11H11FN2O2
222.218943





SEW01633CB   SEW01633DA   SEW01633DE
250 MG    1 GR    5 GR
 93.00 USD 270.00 USD 761.00 USD
Thieno[2,3- b]thiophene- 2-carboxylic acid
14756- 75-3


embedded image


C7H4O2S2
184.22756





AC12788DA   AC12788EA
 1 GR    10 GR
 48.00 USD 155.00 USD
5-methyl-2- thiophene- carboxylic acid
1918- 79-2


embedded image


C6H6O25
142.17244





AC13036EA   AC13036EE
 10 GR    50 GR
 29.00 USD 117.00 USD
Phenyl- boronic acid
98-80- 6


embedded image


C6H7BO2
121.93038





AC13196EA
 10 GR
 74.00 USD
Pyridine- 3-ylacetic acid hydro- chloride
6419- 36-9


embedded image


C7H7NO2•HCl
173.59902 (137.13808)





AC13366DA   AC13366EA
 1 GR    10 GR
 33.00 USD  65.00 USD
2- piperazine- carboxylic acid dihydro- chloride
3022-15- 9


embedded image


C5H10N2O2•2 HCl
203.06848 (130.1466)





AC14674CB   AC14674DA
250 MG    1 GR
179.00 USD 522.00 USD
2-Amino- 3-(6-fluoro- 1H-indol-3- yl)-propanoic acid
7730- 20-3


embedded image


C11H11FN2O2
222.218943










Table 2 recites non-limiting, representative, examples of phosphates suitable to be utilized as calcium sequestration or binding agents.










TABLE 2









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1-Naphthyl phosphate







embedded image


1-Naphthyl phosphate calcium salt trihydrate







embedded image


2,4-Diamino-6,7- diisopropylpteridine phosphate salt







embedded image


2-Cyanoethyl phosphate barium salt dihydrate







embedded image


2-Naphthyl phosphate disodium salt







embedded image


3,9-Bis(2,4- dicumylphenoxy)- 2,4,8,10-tetraoxa-3,9- diphosphasphiro[5.5] undecane







embedded image


6-Benzoyl-2-naphthyl phosphate disodium salt







embedded image


Anilinium hypophosphite










Table 3 recites non-limiting, representative, examples of phosphonates or phosphinates suitable to be utilized as calcium sequestration or binding agents.










TABLE 3









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Dimethyl thiophosphonate







embedded image


Ethyl methylphosphonate







embedded image


Dimethyl vinylphosphonate







embedded image


Trimethyl phosphonoformate







embedded image


Diethyl (trichloromethyl) phosphonate







embedded image


Diethyl cyanophosphonate







embedded image


O,O′-Diethyl methylphosphonothioate







embedded image


Diethyl vinylphosphonate







embedded image


Triethyl phosphonoformate










Table 4 recites non-limiting, representative, examples of phosphonic/phosphoric acids suitable to be utilized as calcium sequestration or binding agents.












TABLE 4











embedded image


Methylphosphonic acid









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(Aminomethyl)phosphonic acid









embedded image


Methylenediphosphonic acid









embedded image


Vinylphosphonic acid









embedded image


Phosphonoacetic acid









embedded image


Dimethylphosphinic acid









embedded image


Ethylphosphonic acid









embedded image


2-Aminoethylphosphonic acid











Table 5 recites non-limiting, representative, examples of amidines suitable to be utilized as calcium sequestration or binding agents.














TABLE 5





Product Code & Pack Size
Product Name
CAS
Structure
MF
MW






















CC12331DA   CC12331EA
 1 GR    10 GR
121.00 USD 443.00 USD
1-benzothiophene-3- carboxamidamidine hydrochloride
465515-36-0


embedded image


C9H8N2S•HCl
212.69686 (176.23592)





MO07267DA   MO07267EA
 1 GR    10 GR
 70.00 USD 270.00 USD
N-Hydroxy- butyramidine
27620-10-6


embedded image


C4H10N2O
102.1362





RF00749DA   RF00749EA
 1 GR    10 GR
 42.00 USD 328.0 USD
3,5- Bis(trifluoromethyl) benzamidine hydrochloride
97603-94-6


embedded image


C9H6F6N2•HCl
292.611398 (256.150458)





RF01501DA   RF10501EA   RF01501EB
 1 GR    10 GR    25 GR
 25.00 USD 225.00 USD 358.00 USD
2,2-dimethyl- propanimidamide
18202-73-8


embedded image


C5H12N2•HCl
136.62452 (100.16368)





MO07766D   MO07766EA   MO07766EB
 1 GR    10 GR    25 GR
 33.00 USD 270.00 USD 490.00 USD
Pyridine-3- carboxamidine hydrochloride 0.5 hydrate
7356-60-7


embedded image


C6H7N3•HCl•0.5 H2O
166.61026 (121.14168)





CC39931CB   CC29931DA
250 MG    1 GR
104.00 USD 260.00 USD
Tetrahydropyran-4- carboxamidine hydrochloride
426828-34-4


embedded image


C6H12N2O•ClH
164.63502 (128.17408)










Table 6 recites non-limiting, representative, examples of boronic acids suitable to be utilized as calcium sequestration or binding agents.














TABLE 6





Product Code & Pack Size
Product Name
CAS
Structure
MF
MW






















AC10430DA   AC10430EA
 1 GR   10 GR
 25.00 USD 189.00 USD
3-amino- phenyl boronic acid 0.5 sulfate
66472- 86-4


embedded image


C6H8BN02•0.5 H2O4S
185.98176 (136.94502)





AC10728DA   AC10728EA
 1 GR   10 GR
 19.00 USD 102.00 USD
4- bromophenyl- boronic acid
5467- 74-3


embedded image


C6H6BBrO2
200.82644





AC13036EA   AC13036EE
10 GR   50 GR
 29.00 USD 117.00 USD
Phenylboronic acid
98-80-6


embedded image


C6H7BO2
121.93038





AC30926DA   AC30926EA
 1 GR   10 GR
 19.00 USD 157.00 USD
2- methylphenyl- boronic acid
16419- 60-6


embedded image


C7H9BO2
135.95726





AC30948DA   AC30948EA
 1 GR   10 GR
 81.00 USD 430.00 USD
4-methoxy- phenylboronic
5720- 07-0


embedded image


C9H9BO3
151.95666





AC34441DA   AC3RRR1E   AC34441EE
 1 GR   10 GR   50 GR
 48.00 USD 155.00 USD 577.00 USD
4-chlorophenyl- boronic acid
1679- 18-1


embedded image


C6H6BClO2
156.37544





AC34443DA
 1 GR
 25.00 USD
4-methylphenyl- boronic acid
5720- 05-8


embedded image


C7H9BO2
135.95726





AC34465DA   AC34465EA
 1 GR   10 GR
 33.00 USD 187.00 USD
Hexylboronic acid
16343- 08-1


embedded image


C6H15BO2
129.9939





AC34468DA   AC34468EA
 1 GR   10 GR
 19.00 USD 117.00 USD
4- (methylsulfanyl) phenylboronic acid
98546- 51-1


embedded image


C7H9BO2S
168.01726





AC34469DA   AC34469E
 1 GR   10 GR
 19.00 USD 151.00 USD
1-naphthyl- boronic acid
13922- 41-3


embedded image


C10H9BO2
171.99026





AC35883DA   AC35883EA
 1 GR 10 GR
 19.00 USD 151.00 USD
3-acetylphenyl- boronic acid
204841- 19-0


embedded image


C8H9BO3
163.96766










Table 7 recites non-limiting, representative, examples of esters or alcohols suitable to be utilized as calcium sequestration or binding agents.














TABLE 7





Product Code & Pack Size
Product Name
CAS
Structure
MF
MW






















CC03622DA CC03622EA
 1 GR    10 GR
102.00 USD 537.00 USD
1-Methyl-1H- imidazole-4- carboxylic acid methyl ester
17289- 19-9


embedded image


C6H8N2O2
140.14172





CC04940DA
 1 GR
106.00 USD
Isoquinoline-4- boronic acid 2,2- dimethyl- propanedial- 1,3-cyclic ester
844891- -01-6


embedded image


C14H16BN02
241.09654





CC19422DA
 1 GR
159.00 USD
3-(2-Methyl- thiazol-4-yl)- benzoic acid methyl ester
850375- -07-4


embedded image


C12H11NO2S
233.28484





MO07248CD   MO07248DA
250 MG    1 GR
 78.00 USD 161.00 USD
3-(5-Bromo- pyridin-3-yl)- [1,2,4] oxadiazole- 5-carboxylic acid ethyl ester
850375- 34-7


embedded image


C10H8BrN3O3
298.09582





MO07285DA   MO07285EA
 1 GR   471.00 GR
 66.00 USD 471.00 USD
(4-Hydroxy- emethyl- benzyl)- carbamic acid tert-butyl ester
123986- 64-1


embedded image


C13H19NO3
237.29876





MO07286CB   MO07286DA   MO07286DE
250 MG    1 GR    5 GR
 78.00 USD 200.00 USD 546.00 USD
(3-Hydroxy- methyl- benzyl)- carbamic acid tert- butyl ester
226070- 69-5


embedded image


C13H19NO3
237.29876





MO07352CB   MO07352DA   MO07352EA
250 MG    1 GR    10 GR
 48.00 USD  95.00 USD 706.00 USD
3-Amino- methyl- benzoic acid methyl ester hydrochloride
17841- 68-8


embedded image


C9H11NO2•HCl
201.65278 (165.19184)





RDP00077DA   RDP00077EA   RPD00077EB
 1 GR    10 GR    25 GR
 42.00 USD  65.00 USD 115.00 USD
(S)-tryptophan ethyl ester hydrochloride
7479- 05-2


embedded image


C13H16N2O2•ClH
268.74318 (232.28224)





BTB06937EE   BTB06937FA
 50 GR   100 GR
 36.00 USD  65.00 USD
4-methoxy-4- oxobutanoic acid
3878- 55-5


embedded image


C5H8O4
132.11612





SB01817EA   SB01817EB
 10 GR    25 GR
 55.00 USD  83.00 USD
Methyl propiolate
922- 67-8


embedded image


C4H4O2
84.07456










Table 8 recites non-limiting, representative, examples of isocyanates suitable to be utilized as calcium sequestration or binding agents.














TABLE 8





Product Code & Pack Size
Product Name
CAS
Structure
MF
MW






















AC29669EA   AC29669EB
 10 GR    25 GR
 31.00 USD  59.00 USD
2-nitrophenyl isocyanante
3320-86-3


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C7H4N2O3
164.12036





AC29670EA   AC29670EB
 10 GR    25 GR
 65.00 USD  70.00 USD
4-nitrophenyl isocyanate
100-28-7


embedded image


C7H4N2O3
164.12036





AC30815DA
 1 GR
 31.00 USD
2,6-difluorophenyl isocyanate
65295-69-4


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C7H3F2NO
155.10372





AC30913DA
 1 GR
 19.00 USD
4-chloro-3- (trifluoromethyl)phenyl isocyanate
327-78-6


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C8H3ClF3NO
221.566129





AC30914DA   AC30914EA
 1 GR    10 GR
 27.00 USD 217.00 USD
2,5-difluorophenyl isocyanate
39718-32-6


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C7H3H2NO
155.103726





AC31411DA   AC31411EA
 1 GR    10 GR
 19.00 USD 155.00 USD
[1,1′-biphenyl]-2-yl isocyanate
17337-13-2


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Cl3H9NO
195.22056





AC31419DA   AC31419E   AC31419EB
 1 GR    10 GR    25 GR
 19.00 USD  74.00 177.00 USD
4-(methylsulfanyl)phenyl isocyanate
1632-84-4


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C8H7NOS
165.20968





AC31420DA
 1 GR
 19.00 USD
2-ethylphenyl isocyanate
40411-25-4


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C9H9NO
147.17656





AC31427EA   AC31427EB
 10 GR    25 GR
 81.00 USD 181.00 USD
4-methyl-3- nitrophenyl isocyanate
13471-69-7


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C8H6N2O3
178.14724





AC31429DA   AC31429EA   AC31429EB
 1 GR    10 GR    25 GR
 19.00 USD  95.00 USD 177.00 USD
2,4-dimethoxyphenyl isocyanate
84370-87-6


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C9H9NO3
179.17536





AC31435DA   AC31435EA
 1 GR    10 GR
 25.00 USD 198.00 USD
4- (chloromethyl)phenyl isocyanate
29173-65-7


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C8H6ClNO
167.59474





AC31931CB
250 MG
 55.00
2-fluoro-5- methylphenyl isocyanate
190774-50-6


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C8H6FNO
151.140143










Table 9 recites non-limiting, representative, examples of oximes suitable to be utilized as calcium sequestration or binding agents.














TABLE 9





Product Code & Pack Size
Product Name
CAS
Structure
MF
MF






















CD11194DA   CD11194EA
 1 GR    10 GR
 81.00 USD 432.00 USD
Azepan-2- one axime
19214-08-5


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C6H12N2O
128.17408





SPB04865DA   SPB04865EA   SPB04865EB
 1 GR    10 GR    25 GR
 51.00 USD  76.00 USD 142.00 USD
2,4- dichloro- benzaldehyde oxime
56843-28-8


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C7H5C12NO
190.0288





SPB04935EA   SPB04935FA
 10 GR   100 GR
321.00 USD 801.00 USD
3,4- dichloro- benzaldehyde oxime
5331-92-0


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C7H5C12NO
190.0288





CD00359DA   CD00359EA   CD00359EE
 1 GR    10 GR    50 GR
 42.00 USD  65.00 USD 232.00 USD
2-furaldehyde oxime
1121-47-7


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C5H5NO2
111.1002





SPB05555DA   SPB05555EA
 1 GR    10 GR
 55.00 USD 332.00 USD
4- (trifluoro- methoxy) benzaldehyde oxime
150162- 39-3


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C8H6F3NO2
205.136349





SPB05820DA   SPB05820EA SPB05820EE
 1 GR    10 GR    50 GR
 42.00 USD  65.00   232.00 USD
2,6-dichloro- benzaldehyde oxime
25185-95-9


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C7H5Cl2NO
190.0288





END00218DA
 1 GR
 53.00 USD
4-phenylbut- 3-en-2-one oxime
2887-98-1


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C10H11NO
161.20344





SPB08294DA   SPB08294EA   SPB08294EB
 1 GR    10 GR   25 GR
 19.00 USD 147.00 USD   275.00 USD
2-chloro-5- fluoro- benzaldehyde oxime
443-33-4


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C7H5ClFNO
173.574203





SPB08414DA   SPB08414EA
 1 GR    10 GR
 53.00 USD 321.00 USD
3,5-dibromo-4- hydroxy- benzaldehyde oxime
25952-74-3


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C7H5Br2NO2
294.9302





MO00284CB MO00284DA
250 MG    1 GR
 68.00   134.00 USD
2-bromo- 1-phenyl-1- ethanone oxime
14181-72-7


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C8H8BrNO
214.06162





KM08088DA
 1 GR
 53.00 USD
4-(3-hydroxy-3- methylbut-1-yn- yl)benzaldehyde oxime
175203-57-3


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Cl2H13NO2
203.24072





TL00712DA   TL00712EA   TL00712EB
 1 GR  10 GR    25 GR
 57.00 USD 337.00 USD 426.00 USD
(1E)-1-(5,6,7,8- tetrahydro- napthalen-2- yl)ethanone oxime
7357-12- 2


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C12H15NO
189.2572





BTB09548DA   BTB09548EA   BTB09548EB
 1 GR    10 GR    25 GR
 29.00 USD  65.00 USD  81.00 USD
3-phenyl- acrylaldehyde oxime
13372-81-1


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C9H9NO
147.17656










Table 10 recites non-limiting, representative, examples of sulfites suitable to be utilized as calcium sequestration or binding agents.














TABLE 10





Product Code & Pack Size
Product Name
CAS
Structure
MF
MF






















AC27651DA
 1 GR
 70.00 USD
1-methyl-1H- benzimidazole- 2- sulfonic acid
5533- 38-0


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C8H9N2O3S
212.223312





AC40114CA   AC40114CB
100 MG 250 MG
 74.00 USD 255.00 USD
Ammonium 7-chloro- 2,1,3- benzoxa- diazole- 4-sulfonate
81377- 14-2


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C6H2ClN2O4S•H4N
251.64434 (233.60588)





MO000766DA   MO00766DE
 1 GR  5 GR
142.00 USD 403.00 USD
6-chloro- imidazo[2,1- b]thiazole- 5-sulfonic acid amide
112582- 89-5


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C5H4ClN3O2S2
237.67866





BTB06262DA   BTB06262EA   BTB06262EB
 1 GR  10 GR  25 GR
 23.00 USD  65.00 USD 115.00 USD
8-chloro- naphthalene- 1-sulfonic acid
145-74- 4


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C10H7ClO3S
242.67678





BTB09138DA
 1 GR
 55.00 USD
2- {[amino(imino) methyl]amino}- ethane-1- sulfonic acid
543-18- 0


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C3H9N3O3S
167.18276





BTB13613DA   BTB13613EA
 1 GR  10 GR
 53.00 USD 321.00 USD
2-(4- aminophenyl)- 6-methyl-1,3- benzothiazole- 7- sulfonic acid
130-17- 6


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C14H12N2O3S2
320.38088





RJC04098DA   RJC04098EA
 1 GR  10 GR
 53.00 USD 321.00 USD
2,5-dichloro- 4-(5- hydroxy-3- methyl-1H- pyrazol-1-yl) benzenesulfonic acid dihydrate
306935- 68-2


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C10H8Cl2NO204S•2H2O
359.18108 (323.15052)





SB01747DA   SB01747EA   SB01747EB
 1 GR  10 GR  25 GR
 42.00 USD  65.00 USD 115.00 USD
3-amino-4- hydroxy-5- nitobenzene-1- sulfonic acid hydrate
175278- 60-1


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C6H6N2O6S•H2O
252.19872 (234.18344)










Table 11 recites non-limiting, representative, examples of sulfates suitable to be utilized as calcium sequestration or binding agents.














TABLE 11






Product






Product Code & Pack Size
Name
CAS
Structure
MF
MF






















AC10430DA   AC10430EA
 1 GR    10 GR
 25.00 USD 189.00 USD
3-amino- phenyl- boronic acid 0.5 sulfate
66472-86-4


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C6H8BNO2•0.5 H2O4S
185.98176 (136.94502)





AC33706CB
250 MG
 27.00 USD
Potassium 1H- indol-3-yl sulfate
2642-37-7


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C8H6NO4S•K
251.29824 (212.19994)










Table 12 recites non-limiting, representative, examples of hydrazines suitable to be utilized as calcium sequestration or binding agents.










TABLE 12









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3-Fluorophenyl- hydrazine hydrochloride







embedded image


4-Fluorophenyl- hydrazine hydrochloride







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4-Iodophenyl- hydrazine







embedded image


2-Nitrophenyl- hydrazine







embedded image


3-Nitrophenyl- hydrazine hydrochloride







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4-Nitrophenyl- hydrazine







embedded image


Phenylhydrazine







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Phenylhydrazine hydrochloride







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Diethyl 1,2- hydrazine- dicarboxylate









Table 13 recites non-limiting, representative, examples of carboxylic acids suitable to be utilized as calcium sequestration or binding agents.










TABLE 13









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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
2355text missing or illegible when filed
85.59
ALDRICH
2461text missing or illegible when filed
86.11










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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH

text missing or illegible when filed 36838

100.12
ALDRICH
277827
136.95










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text missing or illegible when filed indicates data missing or illegible when filed







Table 14 recites non-limiting, representative, examples of aryl carboxylic acids suitable to be utilized as calcium sequestration or binding agents.










TABLE 14









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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH

text missing or illegible when filed

132.42
ALDRICH

text missing or illegible when filed

25.11













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH

text missing or illegible when filed

122.11
ALDRICH

text missing or illegible when filed

120.10













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
P06609
120.10
ALDRICH
P13823
526.33













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
P3404
196.18
ALDRICH
A2244
149.12













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
41894
540.10
ALDRICH
182780
149.98













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
813886
159.14
ALDRICH

text missing or illegible when filed

182.43













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text missing or illegible when filed indicates data missing or illegible when filed







Table 15 recites non-limiting, representative, examples of cycloalkyl carboxylic acids suitable to be utilized as calcium sequestration or binding agents.










TABLE 15









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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW


ALDRICH

text missing or illegible when filed

924.94
ALDRICH
P24606
10839










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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
O1493
124.95
ALDRICH

text missing or illegible when filed

158.52













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
34847
115.12
ALDRICH
725803
126.23













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
56.034
126.17
ALDRICH
28085
129.12













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
81533
122.49
ALDRICH
12802
125.16













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
104950
129.18
ALDRICH
29055
148.39













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text missing or illegible when filed indicates data missing or illegible when filed







Table 16 recites non-limiting, representative, examples of heteroaryl and biaryl acids suitable to be utilized as calcium sequestration or binding agents.










TABLE 16









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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
814654
186.58
ALDRICH
831588
158.19













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
813483
588.47
ALDRICH
834152
100.22













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
054829
188.72
ALDRICH
10847
279.96













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Catalog


Catalog



Brand
Number
MW
Brand
Number
MW





ALDRICH
107926
258.25
ALDRICH
109337
258.25













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Table 17 recites non-limiting, representative, examples of ureas suitable to be utilized as calcium sequestration or binding agents.












TABLE 17











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Urea









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Hydroxyurea









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Semicarbazide hydrochloride









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1-Cyanoisourea sodium salt









embedded image


Biuret









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N-Methylurea









embedded image


o-Methylisourea bisulfate










Table 18 recites non-limiting, representative, examples of hydrazones suitable to be utilized as calcium sequestration or binding agents.










TABLE 18









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Glyoxal mono- dimethyl- hydrazone







embedded image


Benz- aldehyde semi- carbazone







embedded image


Benz- aldehyde p- nitrophenyl- hydrazone







embedded image


Benzo- phenone hydrazone







embedded image


2-Hydroxy- benz- aldehyde phenyl- hydrazone







embedded image


Benzil mono- hydrazone







embedded image


2-Nitro- benz- aldehyde tosyl- hydrazone







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2′- Amino- aceto- phenone phenyl- hydrazone







embedded image


Valero- phenone tosyl- hydrazone









The “calcium sequestration agent” or “calcium binding agent” of the present invention is any agent capable of binding or sequestering calcium ion (CaII) such that the bound or sequestered calcium ion is prevented or inhibited (i.e., reduced) from interacting with other binding agents. In the context of the present invention, the calcium sequestration or binding agent, when administered to the skin of a patient in need of such treatment, binds or sequesters calcium ion in the local area of topical administration and regulates or modulates (i.e., prevents, limits, or inhibits) calcium from acting as a regulator in several (i.e., at least two) steps of melanogenesis and skin pigmentation.


The present composition contain a calcium sequestration or binding agent in an amount effective to reduce pigmentation. For example, the calcium sequestration or binding agent is present in the composition in an amount from about 0.1% to the solubility limit of the calcium sequestration or binding agent in the composition. Preferably, the calcium sequestration or binding agent is present in the composition in the amount of about 0.1% to about 25%, more preferably about 0.2% to about 10%, most preferably about 1% to about 5% by weight.


The pH range of any of the compositions containing a calcium sequestration or binding agent described herein is about 2.5 to about 9.0, preferably about 3.0 to about 7.0, more preferably about 4.0 to about 5.0. Solutions for adjusting pH to appropriate value, e.g., sodium hydroxide (NaOH), may be added to the composition of the present invention, as required.


Preferably, the agent capable of binding or sequestering calcium ion is a phosphate agent. A phosphate is defined as a form of phosphoric acid. The phosphate can contain one or more of phosphorus (P) atoms as follows:

    • i) one phosphorus atom (i.e., orthophosphates) such as H3PO4, any possible salts of H3PO4, or esters of H3PO4 as shown in FIG. 1
    • ii) two phosphorus atoms (i.e., pyrophosphates) such as H4P2O7, any possible salts of H4P2O7, or esters of H4P2O7
    • iii) three phosphorus atoms (i.e., tripolyphosphates) such H5P3O10, any possible salts of H5P3O10, or esters of H5P3O10
    • iv) more than three phosphorus atoms (i.e., polyphosphates) such as H(n+4)(PO3)(n+2), any possible salts of H(n+4)(PO3)(n+2), or esters of H(n+4)(PO3)(n+2)


The structural formula of orthophosphate esters is shown in Formula I, where R1, R2 and R3 are each chosen from branched or unbranched alkyl or alkenyl groups having one or more carbon atoms.




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As used herein, the terms “phosphate” or “phosphates” does not include phosphate derivatives of ascorbic acid, such as sodium or magnesium ascorbyl phosphate, aminopropyl ascorbyl phosphate and other known phosphate derivatives of ascorbic acid with antioxidant properties.


Preferably, the composition can be prepared contains a phosphate form substantially free of calciums such as the phosphoric acid glycerophosphoric acid (C3H9O6P). Glycerophosphoric acid can be present in two different chemical structures, including:

    • i) alpha-glycerophosphoric acid (also known as 3-glycerophosphate, 1-glycerophosphate, 3-phosphoglycerol, alpha-phosphoglycerol, glycerol-3-phosphate, glycerol 1-phosphate, glycerol-3-P, glycerophosphoric acid, 1-glycerophosphoric acid, alpha-glycerophosphate), and
    • ii) beta-glycerophosphoric acid (also known as glycerol 2-phosphate, beta-glycerol phosphate, beta-GP, 2-glycerophosphoric acid, glycerophosphoric acid II).


More preferably, the compositions of the present invention contain the sodium salts of glycerophosphoric acid. The term “glycerophosphoric acid” includes alpha-glycerophosphoric acid, beta-glycerophosphoric acid, or any mixture thereof. Sodium salts of glycerophosphoric can further include the monosodium sodium salt of glycerophosphoric acid (C3H8NaO6P), the disodium sodium salt of glycerophosphoric acid (C3H7Na2O6P), and/or any mixture of the mono- and disodium salts. Sodium salts of glycerophosphoric acid are herein referred as “sodium glycerophosphate”.


The sodium glycerophosphate may further contain some bound water and may be in its hydrated form. The bound water is present in an amount of about 20 to about 40%; preferably between about 25 to about 35% per weight. For the present invention, the sodium glycerophosphate in accordance to the descriptions provided in European Pharmacopoeia 6th Ed. (2007) represents one of the preferred forms and qualities of sodium glycerophosphate.


Excluding any calcium salts of glycerophosphoric acid, the composition may be prepared with other possible salts of glycerophosphoric acid such as the potassium salts of glycerophosphoric acid, the magnesium salts of glycerophosphoric acid, the manganese salts of glycerophosphoric acid, and/or any possible combination thereof including the sodium salts of glycerophosphoric acid. Those skilled in the art will recognize that calcium glycerophosphate or any other calcium salts of phosphoric acid are not phosphates free of calcium and, therefore, are not used in the present invention.


The compositions of the invention contain phosphate(s) in an amount effective to reduce pigmentation. For example, phosphate is present in the composition in an amount from about 0.1% to the solubility limit of the phosphate in the composition. Preferably, the phosphate is present in the composition in the amount of about 0.1% to about 25%, more preferably about 0.2% to about 10%, most preferably about 1% to about 5% by weight.


Preferably, the composition is prepared with sodium glycerophosphate (C3H7Na2O6P×H2O according to specifications provided in European Pharmacopoeia 6th Ed. (2007)) between about 1% to about 5% by weight.


The present invention also provides a skin lightening composition, which is well tolerated. Preferably, such skin lightening compositions provide less skin irritation than is commonly observed with several of the skin lightening products containing hydroquinone; in particular those skin lightening products with additionally contain chemicals with known human skin irritant properties such as retinoic acid, tretinoin, retinol, alpha hydroxy acids such as glycolic or lactic acid, beta hydroxyl acids such as salicylic acid, azelaic acid, free short chain fatty acids, free short chain fatty acid esters, ionic surfactants such as SLS or SLES. Examples of skin lightening products containing hydroquinone along with chemicals with known human skin irritant properties, include, but are not limited to, Tri-Luma® (from Galderma), EpiQuin® Micro (from SkinMedica), Obagi Nu-Derm® Clear and Obagi Nu-Derm® Blender (both from OMP, Inc.) and Lustra® Hydroquinone USP 4% (from TaroPharma).


Specifically, the compositions of the present invention are well tolerated and do not (or only minimally) lead to visibly noticeable skin redness (i.e., erythema, contact dermatitis) or rash (i.e., edema, contact allergy, uticaria) when used once to twice daily for a prolonged period of time (i.e., more than two weeks) under normal in use conditions typical of a skincare or dermatological product. More specifically, the compositions of the present invention provide less skin irritation as compared to skin lightening products containing hydroquinone as observed in repetitive skin irritancy patch tests in humans or animals realized according to the art-recognized models described in J. Toxicol.—Ot. & Ocular Toxicol., 1(2); 109-115. 1982; Contact Dermatitis, 20(1); 3-9. 1989; Lanman, B. M., E. B. Elvers, and C. J. Howard, 1968, “The Role of Human Patch Testing in a Product Development Program,” Joint Conference on Cosmetic Sciences, The Toilet Goods Association (currently, the Cosmetic, Toiletry and Fragrance Association), Washington, D.C., Apr. 21-23, 1968 and Patel, S. M., E. Patrick, and H. I. Maibach, 1976, “Animal, Human, and In Vitro Test Methods for Predicting Skin Irritation,” Dermatotoxicology, Chpt. 33, 5th Ed., Eds. F. N. Marzulli, H. I. Maibach, Taylor, and Frances) (each of which are incorporated herein by reference).


Preferably, the present invention provides methods and compositions for skin depigmentation which are effective in concentrations not resulting in significant skin irritancy as determined by the art-recognized models described herein. Preferably, the present invention provides compositions which are substantially free of calcium, steroids, parabens, anti-microbial preservatives and/or formaldehyde releasers The term “substantially free” as used herein means that the composition of interest (e.g., calcium) is present in the composition in an amount less than 0.1% per weight, preferably less than 0.5% by weight and most preferably less than 0.01% per weight. Preferably, the present invention provides compositions which are suitable for topical application, cosmetically elegant and fast absorbing. That is, the compositions of the present invention do not provide sticky, oily, greasy or otherwise unpleasant feeling when applied onto skin after about one to maximum of about two minutes of application; in case applied as dose per skin area typical for skincare or dermatological products (typically less than 1 mg of composition per cm2).


Additional Active Agents

The present invention also provides stable skin lightening composition, which contain at least one calcium sequestration or binding agent, as described above, and which may further contain at least one additional active agent capable or modulating or reducing (as assessed in vitro and/or in vivo) at least one of the following steps in melanogenesis:


i) uptake of L-tyrosine into melanocytes, and/or


ii) uptake of L-phenylalanine into melanocytes, and/or


iii) turnover of phenylalanine into tyrosine by phenylalanine hydroxylase, and/or


iv) uptake of L-tyrosine into melanosmes, and/or


v) turnover of L-tyrosine into L-Dopa by tyrosinase or tyrosine hydroxylase, and/or


vi) turnover of L-Dopa into dopaquinone by tyrosinase, and/or


vii) transfer of melanosme from melanocytes to keratinocytes.


Several compounds can be described as compounds capable of competing with the transport (active uptake into cell or cell organelle) of L-tyrosine into melanocytes and/or into melanosmes, what may result in a reducing or limiting pool of L-tyrosine for melanogenesis.


Amino Acids

Several amino acids are known competitively inhibit the uptake of L-tyrosine into melanocytes and/or melanosmes. Amino acids L-alanine, glycine, L-isoleucine, L-leucine, but not their D-forms, were described to have hypopigmenting effects in an in vitro assay using B16F0 melanoma cells as cell model for studying melanogenesis. (See Biol Pharm Bull 30, 2007, pp. 677-681). These amino acids were shown not to function as inhibitors of tyrosinase.


Another compound potentially inhibiting tyrosine transport is the sulfur homologue of tyrosine 4-S-cysteinylphenol. (See Biochem J 280, 1991, pp. 721-725). 4-S-cysteinylphenol may also act as substrate of tyrosinase and can therefore be also regarded as inhibitor of tyrosinase. There is some evidence that amino acids L-phenylalanine and L-tryptophan also compete for tyrosine transport. (See Biochem J 280, 1991, pp. 721-725; J Biol Chem 271, 1996, pp. 4002-4008). However, phenylalanine is a precursor of melanin and is therefore excluded in the present invention. L-Tyrosine is formed from L-phenylalanine in the presence of enzyme phenylalanine hydroxylase in melanocytes. Similarly, tryptophan is excluded in the present invention.


Thus, the compositions of the present invention can contain at least one calcium sequestration or binding agent and can further contain L-alanine, glycine, L-isoleucine, L-leucine or a combination thereof. L-alanine, glycine, L-isoleucine, L-leucine can also include esters (e.g. R—COOR′ with R=from amino acid and R′=branched or not branched alky/aryl side chain consisting of up to 18 carbons), amides (R—NH(C═O)—R′), with R=from amino acid and R′=branched or not branched alky/aryl side chain consisting of up to 18 carbons) or both to increase their skin bioavailability. These amino acids also include zwitterions with a sodium or potassium as positive ion (cation).


The present composition can also contain amino acids or their respective derivatives (esters, amides, etc.) in an amount effective to reduce pigmentation or reduce the transport of L-tyrosine either into the melanocyte and/or into the melanosome. For example, the amino acid is present in the composition in an amount from about 0.001% to the solubility limit of the amino acid in the composition. Preferably, the amino acid is present in the composition in the amount of about 0.01% to about 10%, more preferably about 0.05% to about 5%, most preferably about 0.1% to about 2% by weight.


In one embodiment, the invention provides a composition containing one or more phosphates, substantially free of calcium, and further containing L-leucine in an amount of about 0.1% to about 2% by weight. Preferably, the present invention provides a composition containing sodium glycerophosphate (C3H7Na2O6P×H2O; according to specifications provided in Ph. Eur. 6th Ed.) in an amount of about 1% to 5% by weight and further contains L-leucine in an amount of about 0.1% to 2% by weight.


Tyrosinase Inhibitors

The compositions of the present invention can contain at least one calcium sequestration or binding agent and may further contain one or more compounds capable of reducing (as assessed in vitro and/or in vivo) the turnover of L-tyrosine into L-Dopa by tyrosinase or tyrosine hydroxylase, and/or the turnover of L-Dopa into dopaquinone by tyrosinase. Compounds which reduce the turnover of L-tyrosine into L-Dopa and/or reduce the turnover of L-Dopa into dopaquinone are generally referred as tyrosinase inhibitors meaning that they inhibit of tyrosinase activity, tyrosinase gene expression, and/or tyrosine protein formation and/or maturation.


For example, the following compounds have been described to act as tyrosinase inhibitors as assessed in diverse in vitro enzymatic and cellular assays (see Journal of Medicinal Chemistry 42 (2007) 1370-1381 [including supporting information mentioned under Appendix A]; Pigment Cell Res 19, 2006, pp. 550-571) (incorporated herein by reference) and are therefore suitable to be incorporated, either alone or in combination, into the compositions described herein: hydroquinone (1,4-benzenediol); diphenylmethane derivatives (see WO 2004/105736; incorporated herein by reference) including but not limited to 4-(1-phenylethyl)1,3-benzenediol (phenylethyl resorcinol); kojic acid; alpha-arbutin; beta-arbutin; deoxyarbutin, L-mimosine; monobenzyl ether of hydroquinone; hydroquinone fatty esters; L-tropolone; ascorbic acid; benzoic acid; oxyresveratrol (i.e., 2,4,3′,5′-tetrahydroxystilbene); quercetin; benzaldehyde; aloesin; trans-resveratrol; anisaldehyde; cinnamic acid; gnetol; dihydrognetol; 3,3′,4-hydroxy-trans-stilbene; 3,3′,4,4′-hydroxy-trans-stilbene; 3-amino-L-tyrosine, 2-aminophenol; isoliquiritigenin; 4-hydroxychalcone; butein; 4′-hydroxychalcone; 2′,4′-dihydroxychalcone; 2′,4-dihydroxychalcone; trans-4-azobenzene carboxylic acid; cis-4-azobenzene carboxylic acid; trans-4,4′-azobenzene dicarboxylic acid; cis-4,4′-azobenzene dicarboxylic acid; castanospermine; deosynojirimycin; Ko-YGC; Ko-YGV; Ko-YGE; Ko-YGT; Ko-YGL; Ko-YGW; Ko-YGF; Ko-YGH; Ko-YGN; Ko-YGD; Ko-YGG; Ko-YIG; Ko-YYG; Ko-YSG; Ko-YMG; Ko-YQG; Ko-YRG; Ko-YHG; Ko-YNG; Ko-YDG; Ko-FIY; Ko-FRY; Ko-FYY; Ko-FWY; Ko-FFY; Ko-KWY; Ko-KRY; Ko-KKY; Ko-KIY; Ko-FWW; Ko-FWF; Ko-FWI; Ko-FWD; Ko-WWY; glabridin; N-cyclopenthyl-N-nitrosohydroxyl-amine; N-benzyl-N-nitrosohydroxylamine; N-benzyl-N-nitrosohydroxylamine; N-cyclopenthyl-N-nitrosohydroxyl-amine; 3,5-dihydroxy-4′-methoxystilbene; 3,4′-dimethoxy-5-hydroxystilbene; piceid; rhapontigenin; rhaponticin; kurarinone; kushnol F; 4-hydroxyanisol; 2-hydroxy-4-methoxy benzaldehyde; cuminaldehyde; artocarbene; norartocarpanone; 4-propylresorcinol; 3,4-dihydroxybenzonitrile; 3,4,2,4-trans-stilbene; artogomezianol; andalasin; crocusatins H; crocin-1; crocin-3; 3,4-dihydroxycinnamic acid; 4-hydroxy-3-methoxycinnamic acid; anisic acid; 2-methoxycinnamic acid; 3-methoxycinnamic acid; 4-methoxycinnamic acid; kaempferol; glabrene; pyridoxine; Pyridoxamine; Pyridoxal; Pyridoxamine 5′-phosphate; Protocatechuic acid methyl ester; Protocatechuic acid; m-coumaric acid; 3-caffeoylquinic acid; 4-caffeoylquinic acid; 5-caffeoylquinic acid; 3,4-dicaffeoylquinic acid; Caffeic acid; Fisetin; 3,7,4′-trihydroxyflavone; Morin; Luteolin; Apigenin; Galangin; Diethyldithiocarbamate; Phenylthiourea; Phloroglucinol; Eckstolonol; Eckol; Phlorofucofuroeckol; Dieckol; HPABS; Gluthatione; B-Mercaptoethanol; Protocatechualdehyde; 8′-epi-cleomiscosin A; 3,4-Dihydroxybenzaldoxime; 3-Hydroxy-4-methoxybenzaldoxime; 3,4,5-Trihydroxybenzaldoxime; 4-Hydroxy-3-methoxy benzaldoxime; 3-Ethoxy-4-hydroxy benzaldoxime; 4-Hydroxybenzaldoxime; 3,4-Dihydroxy-benzaldehyde-O-ethyloxime; 3,4-Dihydroxybenzaldehyde-O-(4-methylbenzyl)-oxime; 3-Hydroxy-4-methoxy benzaldehyde-O-ethyloxime; 3,4,5-Trihydroxybenzaldehyde-O-ethyloxime; 4-Hydroxy-3-methoxybenzaldehyde-O-ethyloxime; 3-Ethoxy-4-hydroxybenzaldehyde-O-ethyloxime; 4-Hydroxybenzaldehyde-O-ethyloxime; 4-Hydroxy-3-methylbenzaldehyde-O-ethyloxime; 3,5-Dimethyl-4-hydroxybenzaldehyde-O-ethyloxime; (+)-Androst-4-ene-3,17-dione; Androsta-1,4-diene-3,17-dione; 17β-Hydroxyandrosta-1,4-dien-3-one; 11α-Hydroxyandrost-4-ene-3,17-dione; 17β, 11α-Dihydroxyandrost-4-en-3-one; Esculetin; Lappaconitine; Stigmast-5-ene-3β,26-diol; Stigmast-5-ene-3β-ol; Campesterol; arctostaphylos uva ursi (bearberry) leaf extract; glycyrrhiza glabra (licorice) extract; sanguisorba officinalis (burnet) extract; scutellaria baicalensis root (skull cap) extract; and morus alba (mulberry) extract; pinosylvin, dihydropinosylvin; gallic acid; gentisic acid; methyl gentisate; epigallocatechin-3-O-gallate; epigallocatechin; green tea leave extract; ellagic acid; pyognol; myrica rubra leave extract; and/or octadecenedioic acid.


In addition to these recited tyrosinase inhibitors, any biological precursors (pro-forms) of above chemicals can also be included in the present invention. Biological precursors can be simple esters (i.e. methyl-, ethyl-, propyl-, or butyl-esters) of inhibitors with carboxy group. Also included are derivatives of ascorbic acid, such as aminopropyl ascorbyl phosphate, magnesium ascorbyl phosphate, alkyl esters of L-ascorbic acid such as L-ascorbyl palmitrate, L-ascorbyl isopalmitate, L-ascorbyl dipalmitate, L-ascorbyl isostearate, L-ascorbyl distearate, L-ascorbyl diisostearate, L-ascorbyl myristate, L-ascorbyl isomyristate, L-ascorbyl 2-ethylhexanoate, L-ascorbyl di-2-ethylhexanoate, L-ascorbyl oleate and L-ascorbyl dioleate; phosphates of L-ascorbic acid such as L-ascorbyl-2-phosphate and L-ascorbyl-3-phosphate; sulfates of L-ascorbic acid such as L-ascorbyl-2-sulfate and L-acorbyl-3-sulfate; as well as their sodium, potassium, magnesium and/or manganese salts.


The present composition may contain at least one tyrosinase inhibitor in an amount effective to reduce pigmentation or reduce the turnover of L-tyrosine into L-Dopa by tyrosinase or tyrosine hydroxylase, and/or the turnover of L-Dopa into dopaquinone by tyrosinase. For example, the tyrosinase inhibitor can be present in the composition in an amount from about 0.001% to the solubility limit of the tyrosinase inhibitor in the composition. Preferably, the tyrosinase inhibitor is present in the composition in the amount of about 0.01% to about 15%, more preferably about 0.05% to about 10%, most preferably about 0.1% to about 5% by weight. The present invention provides a composition containing one or more phosphates, substantially free of calcium, and further containing: a) hydroquinone (1,4-benzenediol) in an amount of about 0.1% to about 10% by weight, b) 4-(1-phenylethyl)1,3-benzenediol (phenylethyl resorcinol) in an amount of about 0.1% to about 5% by weight, c) arbutin in an amount of about 0.1% to about 10% by weight, d) bearberry leaf extract in an amount of about 0.1% to about 10% by weight, e) kojic acid in an amount of about 0.1% to about 5% by weight, f) oxyresveratrol in an amount of about 0.1% to about 5% by weight, and/or g) gnetol in an amount of about 0.1% to about 5% by weight.


The compositions of the invention may contain, in some embodiments, one or more phosphates, substantially free of calcium, and may further contain hydroquinone (1,4-benzenediol) in an amount of about 1% to about 10% by weight and/or may further contain 4-(1-phenylethyl)1,3-benzenediol (phenylethyl resorcinol) in an amount of about 0.1% to about 5% by weight


Melanosome Transfer Inhibitors

In some embodiments, the compositions of the present invention contain at least one calcium sequestration or binding agent and may additionally contain one or more compounds capable of reducing (as assessed in vitro and/or in vivo) the transfer of melanosmes from melanocytes to keratinocytes. Inhibitors of the transfer of melanosomes from melanocytes to keratinocytes have been described previously (see Pigment Cell Res 19, 2006, pp. 550-571) and include, for example, niacinamide (vitamin B3); centaureidine; lectins; neoglycoproteins and certain inhibitors of serine proteases. In addition, N-acetyl-glucosamine may also reduce melanosme transfer.


The present composition may contain at least one melanosme transfer inhibitor in an amount effective to reduce pigmentation or reduce the transfer of melanosmes from melanocytes to keratinocytes. For example, the melanosme transfer inhibitor can be present in the composition in an amount from about 0.001% to the solubility limit of the melanosme transfer inhibitor in the composition. Preferably, the melanosme transfer inhibitor is present in the composition in the amount of about 0.01% to about 12%, more preferably about 0.05% to about 6%, most preferably about 0.1% to about 3% by weight.


The invention provides a composition containing one or more phosphates, substantially free of calcium, and may further contain hydroquinone in an amount of about 0.1% to about 10% by weight, and further containing a melanosome transfer inhibitor in an amount of about 0.1% to about 3% by weight.


For example, the present invention also provides a composition including one or more phosphates, substantially free of calcium, and also includes 4-(1-phenylethyl)1,3-benzenediol (phenylethyl resorcinol) in an amount of about 0.1% to about 5% by weight, and may also include a melanosome transfer inhibitor in an amount of about 0.1% to about 3% by weight.


In one embodiments, the invention additionally provides a composition containing one or more phosphates, substantially free of calcium; hydroquinone in an amount of about 0.1% to about 10% by weight; 4-(1-phenylethyl)1,3-benzenediol (phenylethyl resorcinol) in an amount of about 0.1% to about 5% by weight: and a melanosome transfer inhibitor in an amount of about 0.1% to about 3% by weight.


Melanocortin Receptor 1 Inhibitors

The compositions of the present invention can contain at least one calcium sequestration or binding agent and can further contain one or more compounds capable of decreasing (as assessed in vitro and/or in vivo) melanocortin receptor 1 (MC1R) activity. For instance, agouti signaling protein regulates skin pigmentation by antagonizing the binding of α-MSH to MC1R. (See Abdel-Malek et al., J. Cell Sci. 2001, 114 (Pt.5):1019-24; Jordan and Jackson, Bioessays. 1998, 20(8):603-606; Voisey and Van Daal, Pigment Cell Res. 2002; 15(1):10-18; Wolff, Pigment Cell Res. 2003, 16(1):2-15). The signaling inhibition through the receptor results from two effects (i) a direct competition at the binding site, and (ii) a downregulation of the receptor signaling. (See Barsh et al., Pigment Cell Res., 2000, 13 Suppl. 8:48-53). As an example, undecylenoyl phenylalanine was described to have an affinity towards MC1R and was shown to act as antagonist of α-MSH in vitro.


In some embodiments, the present composition contains at least one α-MSH antagonist in an amount effective to antagonizing the binding of α-MSH to MC1R. For example, the α-MSH antagonist is present in the composition in an amount from about 0.001% to the solubility limit of the α-MSH antagonist in the composition. Preferably, the α-MSH antagonist is present in the composition in the amount of about 0.01% to about 10%, more preferably about 0.05% to about 5%, most preferably about 0.1% to about 4% by weight.


In one embodiment, the present invention provides a composition containing one or more phosphates, substantially free of calcium, and also contains hydroquinone in an amount of about 0.1% to about 10% by weight and an α-MSH antagonist in an amount of about 0.1% to about 4% by weight. By way of non-limiting example, the α-MSH antagonist is undecylenoyl phenylalanine (with chemical structure: CH2═CH—(CH2)8—CO—NH—CH(—COOH)(—CH2—C6H5), as described in WO2003/061768].


Preferably, the present invention additionally provides a composition containing one or more phosphates, substantially free of calcium; 4-(1-phenylethyl)1,3-benzenediol by weight in an amount of about 0.1% to about 5% by weight; and an α-MSH antagonist in an amount of about 0.1% to about 4% by weight. By way of non-limiting example, the α-MSH antagonist is undecylenoyl phenylalanine.


Alternatively, the present invention also provides a composition including one or more phosphates, substantially free of calcium; hydroquinone in an amount of about 0.1% to about 10% by weight; 4-(1-phenylethyl)1,3-benzenediol by weight in an amount of about 0.1% to about 5% by weight; and an α-MSH antagonist in an amount of about 0.1% to about 4% by weight. Preferably, the α-MSH antagonist is undecylenoyl phenylalanine.


Also provided are compositions containing one or more phosphates, substantially free of calcium; hydroquinone in an amount of about 0.1% to about 10% by weight; 4-(1-phenylethyl)1,3-benzenediol by weight in an amount of about 0.1% to about 5% by weight; and an α-MSH antagonist in an amount of about 0.1% to about 4% by weight. For example, the α-MSH antagonist is undecylenoyl phenylalanine. These compositions may additionally contain a melanosome transfer inhibitor in an amount of about 0.1% to about 3% by weight.


Dermatological Drugs, Biologics and Skin Care Additives

Any of the compositions of the present invention can include at least one calcium sequestration or binding agent and can further include one or more compounds, skincare actives or dermatology drugs and/or biologics other than calcium containing chemicals known in the arts of the treatment of skin pigmentation; general dermatology; cosmetic dermatology; skincare such as, for example skin moisturization; or rejuvenation, including but not limiting to, transforming growth factor (including TGF-beta1, TGF-beta2, TGF-beta3); collagen stimulators such as certain growth factors (e.g. PDGFs, FGFs, etc.) and/or certain peptides (e.g., Matrixyl-3000); stimulators of keratinocyte proliferation such as (e.g. EGF, KGFs, etc.); inhibitors of collagen degrading enzymes (e.g., natural or synthetic inhibitors of MMPs); inhibitors of elastin degrading enzymes (e.g., natural or synthetic inhibitors of elastase); appropriate antioxidants (such as vitamin C, vitamin E, ferulic acid, lipoic acid, polyphenols, ergothioneine, etc.) and their derivatives; appropriate sunscreens and/or solar UV reflectors (e.g., spheres and/or microparticles made of polymers, etc.); anti-inflammatory agents (e.g., steroids, non-steroidal anti-inflammatory agents, anti-inflammatory interleukins, IL-1ra, etc.); emollients; humectants (e.g., glycerin, urea, hyaluronic acid, natural moisturizing factors, etc.); inhibitors of neurotransmitter release; skin penetration agents (e.g., oleic acid, propylene glycol, etc.); skin protectants (e.g., allantoin, calamine, coca butter, cod liver oil, colloidal oatmeal, dimethicone, glycerin, hard fat, kaolin, lanolin, mineral oil, petrolatum, topical starch, white petrolatum, etc.); vitamins (e.g., vitamin B3, vitamin B5, vitamin B6, vitamin D, vitamin F, etc.) and derivatives thereof; keratolytic agents (e.g., urea, alpha-hydroxyl acids (e.g., lactic acid, glycolic acid, citric acid, etc.), beta-hydroxyl acids (e.g., salicylic acid, etc.), and polyhydroxyacids, etc.)); external analgesic agents (e.g., benzocaine, butamben picrate, dibuccaine, diemethisoquin, dyclonine, lidocaine, pramoxine, tetracaine, etc.) and their respective salts; antipruritic agents; cell metabolism stimulants (e.g., pantothenic acid, niacin, nicotinic acid esters, etc.); appropriate anti-acne agents; astringents; counter irritants; antihistamine agents; azelaic acid; retinoic acid, retinol and/or derivatives; natural oils (e.g., jojoba oil, shea butter, etc.); appropriate biological components (e.g., cell lysate, human dermal fibroblast lysate, conditioned cell culture medium, stem cell components, etc.); mixtures of growth factors (e.g., PSP® from Neocutis Inc, Nouricel-MD® from SkinMedica Inc., etc.); and/or wound healing agents.


Formulations and Modes of Administration

Those skilled in the art will recognize that any of the compositions of the present invention can contain at least one calcium sequestration or binding agent and can further contain one or more compounds capable of chemically stabilizing any of the ingredients present in the composition. Compounds that help to chemically stabilize any of the ingredients may include, but are not limited to, sodium metabisulfite; sodium bisulfate; BHT; BHA; propyl gallate; disodium EDTA; lemon extract; antioxidants, including ascorbic acid (vitamin C) and its derivatives such as phosphate derivatives of ascorbic acid including sodium or magnesium ascorbyl phosphate, aminopropyl ascorbyl phosphate, and other known phosphate derivatives of ascorbic acid having antioxidant properties; and tocopherol and derivatives of tocopherol such as, sodium vitamin E phosphate (VEP), lauryl imino dipropionic acid tocopheryl phosphate, tocopheryl glucoside, tocopheryl succinate, tocophersolan (tocopheryl polyethylene glycol 1000 succinate), disodium lauriminodipropionate tocopheryl phosphates, tocophereth-5,10,12,18, and 50 (polyethylene glycol (PEG) tocopheryl ethers. Sulfites such as sodium metabisulfite, and/or sodium bisulfate are particularly useful to stabilize hydroquinone or other chemically labile (i.e., easily being oxidized) compounds present in the said composition. In general, the compositions may contain between about 0.05 to 0.5% sulfites by weight.


The compounds, compositions and formulations of the instant invention can be administered by any means known in the art. Preferably, the compositions of the present invention are formulated as a topical preparation or dosage form. Topical preparations are ointments, creams, gels and lotions. The definition of these topical dosage forms is given by Bhuse L. et al. (Int J Pharm 295: 2005, 101-112) (incorporated by reference). The carrier can also be a liquid, a foam, a mousse, a spray, an aerosol, an oil-in-water emulsion, a water-in-oil emulsion, a triple emulsion, a nanoemulsion, a microemulsion, a hydrogel, a solution, a paste, a jelly, a patch, a wipe, a cloth, and/or a dispersion or suspension. The carrier may contain niosomes, liposomes, nanospheres, microspheres, nanoparticles, microparticles, lipid droplets, solid particles, pigments and/or water droplets.


In one preferred embodiment, the carrier is a cream. In various embodiments, the cream may be either an oil-in-water mixture, or a water-in-oil based carrier. In another preferred embodiment, the carrier is a gel or hydrogel.


Those skilled in the art will recognize that any reference herein to a composition of the invention includes any composition containing one or more phosphates free of calcium in conjunction with a carrier.


Those skilled in the art will also recognize that additional agents can be added in any of the methods and compositions of the invention. These agents may include, but are not limited to, e.g., antimicrobial agents (e.g., parabens, phenoxyethanol, chlorophenesin, propylene glycol, butylene glycol, ethylhexylglycerin, imidazolidinyl urea, methylchloroisothiazolinone, potassium benzoate, DMDM hydantoin, etc.), etc.), color additives, fragrances, sensory stimulating agents, polymers, surfactants, water, oils, etc. Information regarding the preparation of compositions, can be found, e.g., in Volume 3: Liquid Products, Volume 4: Semisolid Products and Volume 5: Over-the-Counter Products, of the ‘Handbook of Pharmaceutical Manufacturing Formulations’ (edited by S. K. Niazi, CRC Press, Boca Raton, 2004). Moreover, information regarding the preparation of cosmetic or cosmeceutical compositions may be found in the formulary archive of the Happy Magazine (see http://www.happi.com/formulary). In addition, formulary information for cosmetic or cosmeceutical compositions can be also obtained from diverse ingredient suppliers such as Croda, Ciba, BASF, Dow Chemicals, etc.


The present invention provides stable and none to little irritating (i.e., no or only limited and acceptable skin irritancy) compositions for topical application to the skin to treat skin pigmentation disorders, such as melasma, post-inflammatory hyperpigmentation, pigmentation changes due to skin aging, or any other skin conditions related with normal such as skin of color or abnormal pigmentation such as hypo- or hyper-pigmentation in humans.


Stable compositions can be obtained by (1) selecting appropriate calcium sequestration or binding agent concentration(s), (2) selecting appropriate salt form(s) of the agent other than calcium salt(s), (3) adjusting the pH of the composition, (4) selecting appropriate type of formulation (e.g., liquid, a foam, a mousse, a spray, an aerosol, an oil-in-water emulsion, a water-in-oil emulsion, a triple emulsion, a nanoemulsion, a microemulsion, a hydrogel, a solution, a paste, a jelly, a patch, a wipe, a cloth, and/or a dispersion or suspension) for the composition, (5) selecting appropriate ingredients allowing to stabilize the composition, (6) selecting and appropriate container for composition suitable for topical administration (e.g., tube, airless pump, jar, vial, monodose, etc.), and/or (7) selecting conditions allowing the preparation of a stable preparation (e.g., preparation of composition under inert gas, etc.).


The term “stable” when applied to the compositions of the instant invention is defined as having a comparable color when the composition is placed on a flat and inert surface (i.e., removed from its container) under normal ambient air and light conditions (i.e., air and light conditions as normally exist in the living room at home) when kept for at least one month at room temperature (about 25° C.).


Other than the above-defined color stability, stability of the composition may further include physical stability (e.g., viscosity, odor, appearance, texture, etc.) and chemical stability of the selected active(s) such as a drug active (e.g., calcium sequestration agent, hydroquinone, etc.). Chemical stability can be assessed using HPLC or other appropriate analytical methods. When the composition is placed (e.g., filled) into a suitable container (e.g., a tube, pump, jar, etc.), the composition should be chemically stable (i.e., less than a ±10% change in the content as compared to the baseline value) for at least a year under normal storage condition (i.e., room temperature; or common temperature fluctuations occurring in house/living room/bath room due to changes in season or geographical region). Stability may also be tested under accelerated conditions at elevated temperatures (e.g., 40° C. or higher) in order to predict stability of the composition at room temperature (about 25° C.).


The compositions of the present invention may be applied to the entire body, including the face. These compositions may be applied as needed or alternatively, as part of a skin care routine. Preferably, the composition is applied weekly. More preferably, the composition is applied once daily at night at least half an hour before bedtime. However, it can be also applied twice daily, with the preferred mode being once in the morning and once in the evening. When compositions are applied twice daily, the compositions may be the same or different for each application. For example, the same composition may be applied twice daily or alternately, one composition may be applied in the morning and a second, different composition, may be applied in the evening. The compositions can be applied to any mammal (e.g., a primate, rodent, feline, canine, domestic livestock (such as cattle, sheep, goats, horses, and pigs). Preferably, the compositions are applied to humans.


In some embodiments, a sunscreen formulation offering a SPF 15 or higher is used in addition during day time in order to protect skin from sun exposure or damage. Additionally, the compositions of the present invention may further contain one or more sunscreen active agents, such as those that provide a UV-B filter and, in some embodiments, additionally a UV-A filter. Examples of suitable UV-A and UV-B filters include those described in U.S. Pat. No. 7,078,022 (incorporated herein by reference).


Preferably, the compositions of the invention dry quickly and cleanly (without visible residue or significant stickiness) after application of a normal amount (i.e., 0.2 to 2 mg composition per cm2) on the skin.


The examples as set forth herein are meant to exemplify the various aspects of carrying out the invention and are not intended to limit the invention in any way. Unless otherwise specified, it is to be understood that the concentrations of the component ingredients in the compositions of the invention are in %, w/w, based on the total weight of the composition.


Example 1

Exemplary compositions formulated in accordance with the present invention are presented in Table 19. These compositions serve as illustrative formulations which provide several of the advantageous features of the invention, namely, mildness to the skin after application with no or only limited skin irritancy; clearness and non-greasiness upon application (transparent) to face and other skin areas other than the palms and the soles; and quick-drying, particularly when the compositions are preferably formulated as water-in-oil formulations.














TABLE 19







INGREDIENT


% BY


NO.
PHASE
(TRADE NAME)
INCI DESIGNATION
SUPPLIER
WEIGHT




















1
A
DEIONIZED WATER
WATER (AQUA)

63.310


2
A
NA2EDTA
DISODIUM EDTA
AKZO/DEWOLF
0.100


3
A
KELTROL CG-T
XANTHAN GUM
CP KELCO/
0.300






UNIVAR


4
B
LIPOWAX D
CETEARYL ALCOHOL
LIPO
8.250





CETEARETH-20


5
B
LIPO GMS 450
GLYCERYL STEARATE
LIPO
6.000


6
B
CERAPHYL 230
DIISOPROPYL ADIPATE
ISP SUTTON
5.000


7
B
DC TORAY FZ-3196
CAPRYLYL METHICONE
DOW CORNING/
3.000






UNIVAR


8
B
DC 200 FLUID 100 CST
DIMETHICONE
DOW CORNING/
1.000






UNIVAR


9
B
LIPOVOL J

SIMMONDSIA

LIPO
1.000






CHINENSIS (JOJOBA)






SEED OIL


10
B
SHEA BUTTER HMP

BUTYROSPERMUM

EARTH SUPPLIED
1.000






PARKII (SHEA BUTTER)

PRODUCTS


11
B
VITAMIN E ACETATE OIL
DL-ALPHA
BASF/
0.200




(USP, FCC)
TOCOPHERYL ACETATE
CHEMCENTRAL


12
C
DEIONIZED WATER
WATER (AQUA)

0.100


13
C
ELESTAB CPN ULTRA PURE
CHLORPHENESIN
COGNIS
0.300


14
C
PHENOXETOL
PHENOXYETHANOL
CLARIANT
0.600


15
C
SEPIWHITE MSH
UNDECYLENOYL
SEPPIC
0.500





PHENYLALANINE


16
C
SODIUM GLYCEROPHOSPHATE
SODIUM
DR. PAUL
3.000




(Ph. Eur. 6 Ed, Item# 500012045500)
GLYCEROPHOSPHATE
LOHMANN


17
C
L-LEUCINE
LEUCINE
AJINOMOTO
1.000


18
C1
CITRIC ACID 50% SOLUTION
CITRIC ACID
PCI
1.920




(TO pH 4.5-5.0)


19
C2
GLYCERIN 99.7% (USP)
GLYCERIN
ACME-HARDESTY
2.000


20
C2
SYMWHITE 377
PHENYLETHYL
KAH/SYMRISE
0.500





RESORCINOL


21
C2
VITAGEN
AMINOPROPYL
BASF
0.500





ASCORBYL PHOSPHATE


22
D
SIMULGEL INS 100
HYDROXYETHYL
SEPPIC
0.420





ACRYLATE/SODIUM





ACRYLOYLDIMETHYL





TAURATE COPOLYMER





ISOHEXADECANE





POLYSORBATE 60




TOTAL




100.00









Such compositions (e.g., Table 19) were generally prepared in a clean and sanitized stainless steel vessel, which was suitable for blending products containing hydroquinone, as described herein below:

  • PHASE A: DISPERSE KELTROL IN WATER, MIX UNTIL ALL HYDRATES;
    • ADD REMAINING PHASE A INGREDIENTS, HEAT TO ABOUT 75° C. WHILE MIX UNTIL ALL DISSOLVES.
  • PHASE B: COMBINE PHASE B INGREDIENTS IN A SEPARATE VESSEL AND MIX WHILE HEATING TO 75° C.; ONCE ALL WAXES MELT AND PHASE IS AT TEMP AND UNIFORM, SLOWLY ADD TO PHASE A; COOL TO 35° C.
  • PHASE C: COMBINE PHASE C INGREDIENTS WITH MECHANICAL STIRRING UNIT AND MIX WITH MODERATE AGITATION
  • PHASE C1: USE PHASE C1 TO ADJUST pH OF PHASE C TO 4.0-4.5
  • PHASE C2: COMBINE PHASE C2 AND MIX WHILE HEATING SLIGHTLY TO 40° C.; CONTINUE MIXING UNTIL POWDERS DISSOLVE THEN ADD TO PHASE C; ADD PHASE C TO BATCH WITH MODERATE AGITATION
  • PHASE D: ADD PHASE D TO BATCH, MIX UNTIL UNIFORM;
    • HOMOGENIZE THE BATCH AT 3500 RPM FOR 5 MINUTES; SWITCH TO IMPELLER MIXING; COOL TO ROOM TEMPERATURE.


The composition obtained as described in Example 1 was then filled into an airless pump container (e.g., 30 ml TopFill airless pump from MegaPlast—Mega Pumps) and then tested for physical stability (color, odor, viscosity, pH, appearance, etc.) under accelerated conditions (40 to 50° C.) for up to three months. During this period of time, the composition filled into the airless pump was stable (i.e., color, odor, viscosity, pH and appearance did not change or only changed to a limited and acceptable extent (±10% from baseline)).


The composition obtained as described in Example 1 does not leave greasy or oily residues on the skin and dries quickly and cleanly (without visible residue or significant stickiness) within one to two minutes after application on the skin.


Example 2

Additional compositions formulated in accordance with the present invention are presented in Table 20. Again, these compositions serve as illustrative formulations which provides the advantageous features of the invention, namely, mildness to the skin after application with no or only limited skin irritancy; clearness and non-greasiness upon application (transparent) to face and other skin areas other than the palms and the soles; and quick-drying, particularly when the compositions are preferably formulated as water-in-oil formulations.














TABLE 20







INGREDIENT


% BY


NO.
PHASE
(TRADE NAME)
INCI DESIGNATION
SUPPLIER
WEIGHT




















1
A
DEIONIZED WATER
WATER (AQUA)

59.680


2
A
NA2EDTA
DISODIUM EDTA
AKZO
0.100


3
A
KELTROL CG-T
XANTHAN GUM
CP KELCO
0.300


4
A
ELESTAB CPN ULTRA PURE
CHLORPHENESIN
COGNIS
0.300


5
A
PHENOXETOL
PHENOXYETHANOL
CLARIANT
0.600


6
A
SEPIWHITE MSH
UNDECYLENOYL
SEPPIC
0.500





PHENYLALANINE


7
A
SODIUM GLYCEROPHOSPHATE
SODIUM
DR. PAUL
3.000




(Ph. Eur. 6 Ed, Item# 500012045500)
GLYCEROPHOSPHATE
LOHMANN


8
A
L-LEUCINE
LEUCINE
AJINOMOTO
1.000


9
B
LIPOWAX D
CETEARYL ALCOHOL
LIPO
6.000





CETEARETH-20


10
B
LIPO GMS 450
GLYCERYL STEARATE
LIPO
6.000


11
B
CERAPHYL 230
DIISOPROPYL ADIPATE
ISP SUTTON
3.000


12
B
DC TORAY FZ-3196
CAPRYLYL METHICONE
DOW CORNING
3.000


13
B
DC 200 FLUID 100 CST
DIMETHICONE
DOW CORNING/
1.000






UNIVAR


14
B
LIPOVOL J

SIMMONDSIA

LIPO
1.000






CHINENSIS (JOJOBA)






SEED OIL


15
B
SHEA BUTTER HMP

BUTYROSPERMUM

EARTH SUPPLIED
1.000






PARKII (SHEA BUTTER)

PRODUCTS


16
B
VITAMIN E ACETATE OIL
DL-ALPHA
BASF/
0.200




(USP, FCC)
TOCOPHERYL ACETATE
CHEMCENTRAL


17
C
CITRIC ACID 50% SOLUTION
CITRIC ACID
PCI
1.920




(TO pH 4.5-5.0)


18
D
EASTMAN ™ HYDROQUINONE
HYDROQUINONE
EASTMAN/
4.000




(USP GRADE)

CHEMPOINT


19
E
SODIUM METABISULFITE
SODIUM
UPI
0.400




(NF/FCC)
METABISULFITE


20
F
GLYCERIN 99.7% (USP)
GLYCERIN
ACME-HARDESTY
2.000


21
F
SYMWHITE 377
PHENYLETHYL
KAH/SYMRISE
0.500





RESORCINOL


22
F
VITAGEN
AMINOPROPYL
BASF
0.500





ASCORBYL PHOSPHATE


23
G
SIMULGEL INS 100
HYDROXYETHYL
SEPPIC
4.000





ACRYLATE/SODIUM





ACRYLOYLDIMETHYL





TAURATE COPOLYMER





ISOHEXADECANE





POLYSORBATE 60




TOTAL




100.00









Such compositions (e.g., Table 20) were generally prepared in a clean and sanitized stainless steel vessel, which was suitable for blending products containing hydroquinone, as described herein below:

  • PHASE A: DISPERSE KELTROL IN WATER, MIX UNTIL ALL HYDRATES; ADD EDTA, MIX UNTIL ALL DISSOLOVES;
    • ADD REMAINING PHASE A INGREDIENTS, HEAT TO 75° C. WHILE MIX UNTIL ALL DISSOLVES.
  • PHASE B: COMBINE PHASE B INGREDIENTS, HEAT TO 75° C., MIX UNTIL ALL MELTED AND UNIFORM;
    • WHEN BOTH PHASE A AND PHASE B AT 75° C., ADD PHASE B INTO PHASE A WITH AGITATION MIX FOR 10 MINUTES, START COOLING TO 50° C.
  • PHASE C: ADJUST pH WITH PHASE C TO pH 4.5-5.0, COOL TO 45° C.
  • PHASE D: ADD PHASE D TO BATCH WITH MIX, MIX UNTIL ALL DISSOLVES AND UNIFORM.
  • PHASE E: ADD PHASE E TO BATCH WITH MIXING, MIX UNTIL ALL DISSOLVES.
  • PHASE F: COMBINE PHASE F INGREDIENTS, SLIGHTLY HEAT AND MIX UNTIL ALL DISSOLVES, ADD TO THE BATCH.
  • PHASE G: ADD PHASE G TO BATCH, MIX UNTIL UNIFORM;
    • HOMOGENIZE THE BATCH AT 3500 RPM FOR 5 MINUTES, SWITCH TO IMPELLER MIXER, MIX;
    • ADJUST pH WITH PHASE C TO pH 4.5-5.0 IF NECESSARY.


The composition obtained as described in Example 2 was then filled into aluminum tubes (or aluminum coated plastic tubes) and then tested for physical stability (color, odor, viscosity, pH, appearance) and chemical stability (by HPLC) of hydroquinone under accelerated conditions (40 to 50° C.) for up to three months. During this period of time, the composition filled into aluminum tubes was stable (i.e., color, odor, viscosity, pH and appearance did not change or only changed to a limited and acceptable extent (±10% from baseline) and the hydroquinone content remained between 3.84% to 4.24% (weight %).


The composition obtained as described in Example 2 does not leave greasy or oily residues on the skin and dries quickly and cleanly (without visible residue or significant stickiness) within one to two minutes after application on the skin.


Example 3

Additional compositions formulated in accordance with the present invention are presented in Table 21. These compositions serve as illustrative formulations, which provide the advantageous features of the invention, namely, stability of the composition, mildness to the skin after application with no or only limited and acceptable skin irritancy; clearness and non-greasiness upon application (transparent) to face and other skin areas other than the palms and the soles; and quick-drying, particularly when the compositions are preferably formulated as water-in-oil formulations.













TABLE 21







INGREDIENT

% BY


NO.
PHASE
(TRADE NAME)
INCI DESIGNATION
WEIGHT



















1
A
DEIONIZED WATER
WATER (AQUA)
59.680


2
A
NA2EDTA
DISODIUM EDTA
0.100


3
A
KELTROL CG-T
XANTHAN GUM
0.300


4
A
ELESTAB CPN ULTRA PURE
CHLORPHENESIN
0.300


5
A
PHENOXETOL
PHENOXYETHANOL
0.600


6
A
SEPIWHITE MSH
UNDECYLENOYL PHENYLALANINE
0.500


7
A
SODIUM GLYCEROPHOSPHATE (Ph.
SODIUM GLYCEROPHOSPHATE
3.000




Eur. 6 Ed, Item# 500012045500)


8
A
L-LEUCINE
LEUCINE
1.000


9
B
CITRIC ACID 50% SOLUTION
CITRIC ACID
1.920




(TO pH 4.5-5.0)


10
C
LIPOWAX D
CETEARYL ALCOHOL CETEARETH-20
6.000


11
C
LIPO GMS 450
GLYCERYL STEARATE
6.000


12
C
CERAPHYL 230
DIISOPROPYL ADIPATE
3.000


13
C
DC TORAY FZ-3196
CAPRYLYL METHICONE
3.000


14
C
DC 200 FLUID 100 CST
DIMETHICONE
1.000


15
C
LIPOVOL J

SIMMONDSIA CHINENSIS (JOJOBA) SEED OIL

1.000


16
C
SHEA BUTTER HMP

BUTYROSPERMUM PARKII (SHEA BUTTER)

1.000


17
C
VITAMIN E ACETATE OIL
DL-ALPHA TOCOPHERYL ACETATE
0.200




(USP, FCC)


18
D
EASTMAN ™ HYDROQUINONE (USP
HYDROQUINONE
4.000




GRADE)


19
E
SODIUM METABISULFITE (NF/FCC)
SODIUM METABISULFITE
0.400


20
F
GLYCERIN 99.7% (USP)
GLYCERIN
2.000


21
F
SYMWHITE 377
PHENYLETHYL RESORCINOL
0.500


22
F
VITAGEN
AMINOPROPYL ASCORBYL PHOSPHATE
0.500


23
G
SIMULGEL INS 100
HYDROXYETHYL ACRYLATE/SODIUM
4.000





ACRYLOYLDIMETHYL TAURATE





COPOLYMER ISOHEXADECANE





POLYSORBATE 60



TOTAL



100.00









Such compositions (e.g., Table 21) were generally prepared in a clean and sanitized stainless steel vessel, which was suitable for blending products containing hydroquinone, as described herein below:

  • PHASE A: WEIGHT WATER AND HEAT TO 70° C.
    • DISPERSE KELTROL IN WATER, MIX UNTIL ALL HYDRATES; ADD EDTA, MIX UNTIL ALL DISSOLOVES;
    • THEN ADD REMAINING PHASE A INGREDIENTS ONE BY ONE; MIX UNTIL ALL DISSOLVES.
  • PHASE B: ADD CITRIC ACID 50% SOLUTION TO PHASE A; MIX WELL; CHECK pH OF BATCH; pH SHOULD BE BETWEEN 4.5-5.0
  • PHASE C: COMBINE PHASE C INGREDIENTS;
    • HEAT TO 60° C., MIX UNTIL ALL MELTED AND UNIFORM;
    • WHEN BOTH, COMBINED PHASES A & B AND PHASE C ARE AT 60° C., ADD PHASE C INTO COMBINED PHASES A & B WITH AGITATION MIX FOR 10 MINUTES; START COOLING TO 45° C.
  • PHASE D: ADD PHASE D TO BATCH WITH MIX, MIX UNTIL ALL DISSOLVES AND UNIFORM.
  • PHASE E: ADD PHASE E TO BATCH WITH MIXING, MIX UNTIL ALL DISSOLVES.
  • PHASE F: COMBINE PHASE F INGREDIENTS, SLIGHTLY HEAT AND MIX UNTIL ALL DISSOLVES, ADD TO THE BATCH.
  • PHASE G: ADD PHASE G TO BATCH, MIX UNTIL UNIFORM;
    • HOMOGENIZE THE BATCH AT 3500 RPM FOR 5 MINUTES, SWITCH TO IMPELLER MIXER, MIX FOR 5 to 10 MINUTES;
    • CHECK FINAL pH;
    • ADJUST pH WITH PHASE B TO pH 4.5-5.0 IF NECESSARY.


Compositions obtained as described in Example 3 were then filled into aluminum tubes (or aluminum coated plastic tubes) and then tested for physical stability (color, odor, viscosity, pH, appearance) and chemical stability (by HPLC; following USP protocol for hydroquinone analysis) of hydroquinone under accelerated conditions (40 to 50° C.) for up to three months. During this period of time, the composition was stable and the hydroquinone content remained between 3.84% to 4.24% (weight %).


These compositions do not leave greasy or oily residues on the skin and dries quickly and cleanly (without visible residue or significant stickiness) within one to two minutes following application on the skin.


Example 4

The results of skin tolerability testing (e.g., no or only limited and acceptable skin irritancy) of the compositions formulated in accordance with the present invention are presented below.


The compositions of the present invention can be evaluated by acute (1 day) or repetitive (more than one day) human irritancy patch test to assess the skin irritation potential. The repetitive human irritancy patch test provides “exaggerated” irritation data since the test material is applied repetitively at a rather large dose (i.e., >20 mg per cm2) under occlusive (i.e., allowing no water diffusion from skin surface to air) or semi-occlusive conditions (i.e., allowing limited water diffusion from skin surface to air). Therefore, the repetitive human irritancy patch test allows easily distinguishing skin irritation (i.e., skin irritation potential) of different compositions.


The composition obtained as described in Example 3 was evaluated by repetitive human irritancy patch test over a period of three weeks (with 15 observations (i.e., evaluation of patch application sites for severity of skin irritation); one observation before patch application at beginning of study followed by 14 additional observations; see below for more details) on the back of 25 subjects. The test was performed according to standard irritancy patch testing by an independent contract organization specialized in consumer product testing. Several currently commercialized skin lightening prescription products with 4% hydroquinone were also evaluated under identical conditions for comparison. The repetitive human irritancy patch test demonstrated that the composition obtained as described in Example 3 was equally or better tolerated than a series of currently commercialized skin lightening prescription products with 4% hydroquinone. (See FIG. 1)


As shown in FIG. 1, the following compositions were evaluated:

    • i) Composition described in Example 3
    • ii) Composition A: composition with 4% hydroquinone and further containing sodium lauryl sulfate and lactic acid (OBAGI NU-DERM® Blender® (PM 5) by OMP Inc., Long Beach, CA 90802; Lots: 6K2423 and 8E1677)
    • iii) Composition B: composition with 4% hydroquinone and further containing sodium lauryl sulfate and lactic acid (OBAGI-C RX SYSTEM™ C-Therapy Night Cream (PM) by OMP Inc., Long Beach, CA 908020; Lot: 8E1440)
    • iv) Composition C: composition with 4% hydroquinone and further containing glycolic acid (LUSTRA® Hydroquinone USP 4% by Taro Pharmaceuticals U.S.A, Hawthorne, NY 10532; Lot: H8114)
    • v) Composition D: composition with 4% hydroquinone and further containing sodium lauryl sulfate (GLYTONE Skin Bleaching/Clarifying Cream Hydroquinone USP 4% by Pierre Fabre/Genesis Pharmaceutical Inc., Parsippany N.J. 07054; Lot: 1058/01)


      The following standard method was used to assess skin irritation:


The upper back between the scapulae served as treatment area. Approximately 0.2 grams of each test material was applied to the 1 inch×1 inch absorbent pad portion of an adhesive strip. When secured to the appropriate treatment site, these dressings formed semi-occlusive patches. Each test material was applied to the appropriate treatment site Monday through Friday to maintain twenty-one (21) consecutive days of direct skin contact. Patches applied on Friday remained n place until the following Monday. Evaluations of the test sites were conducted prior to each patch application. It was noted that due to inclement weather, two of the 25 subjects were unable to report, as scheduled. They were instructed to keep their patches in place and return on the following day. If a test site had been observed to exhibit an evaluation score of a “3” or higher, the application of test material to this site would have been discontinued and the observed score of “3” (or higher) would be recorded for the remaining study days.


The following evaluation key was used: (0) no visible skin reaction; (+) barely perceptible or spotty erythema; (1) mild erythema covering most of the test site; (2) moderate erythema, possible presence of mild edema; (3) marked erythema, possible edema; (4) severe erythema, possible edema, vesiculation, bullae and/or ulceration.


Example 5

The results of color stability of the compositions formulated in accordance with the present invention are presented below. In Examples 1, 2 and 3, the color of the compositions of the present invention is described as being stable (e.g., characteristic white color of compositions does not significantly change for up to three months at elevated temperatures as evaluated visually with the naked eye) when the composition is placed (i.e., filled) into an adequate container.


In this Example, the color stability was evaluated after the composition was removed from its typical (e.g., commercialized) container such as aluminum tube, aluminum coated plastic tube, or airless pump. A pea size amount was placed onto a flat, inert, white surface (e.g., porcelain dish) and left under normal environmental conditions (i.e., temperature, light, air, etc.) of a room (i.e., living room) in a household for at least two weeks. The color of the composition was documented by standard, digital color photography at beginning and at end of the observation period. Several currently commercialized skin lightening prescription products with 4% hydroquinone were also evaluated under identical conditions for comparison.


As shown in FIG. 2, the following compositions were evaluated:

    • i) Composition A: composition described in Example 3
    • ii) Composition B: composition with 4% hydroquinone and further containing retinol (EpiQuin® Micro by SkinMedica, Carlsbad, Calif. 92010)
    • iii) Composition C: composition with 4% hydroquinone and further containing 0.01% fluocinolone acetonide and 0.05% tretinoin (Tri-Luma® Cream by Galderma Laboratories, Fort Worth, Tex. 76177)
    • iv) Composition D: composition with 4% hydroquinone and further containing sodium lauryl sulfate and lactic acid (OBAGI NU-DERM® Blender® (PM 5) by OMP Inc., Long Beach, CA 90802)


The compositions were removed from their typical container and placed onto porcelain dish and left under normal environmental conditions (i.e., temperature, light, air, etc.) of a room (i.e., living room) in a household for 17 days. The composition of the present invention (Composition A) did not show any significant color change after 17 days as judged by photography or visually. However, Compositions B, C and D showed all significant (i.e., clearly visible) color changes (i.e., color is changing from white to brown or brownish, or becoming darker, more brownish, or darker yellow) after 17 days. These color changes became more visible with time. The color changes are mainly due to oxidation of hydroquinone, which is a constituent of Compositions B, C and D. While hydroquinone is also a constituent of Composition A, this experiment thus illustrates that the hydroquinone of Composition A is stable under the conditions of this experiment.


Although the color changes described in this Example for Composition B, C and D generally occurs when the composition is placed outside its typical container, these observed color changes are not desirable, as such color changes may affect the efficacy of the product (i.e., composition being exposed to air and light after it is applied onto skin). Furthermore, thee color changes would occur after short time once some composition adheres to the outside of the container (e.g., the tube outlet or pump head) after the first and all subsequent uses of the composition. All of these factors make the composition less desirable to use, which consequently affects the patient's adherence to the recommended course of treatment (i.e., patient compliance) and therefore reduces the likelihood for an efficient treatment outcome.


Example 6

The compositions obtained as described in Examples 1, 2, and 3 were evaluated for tolerability and efficacy in treating skin pigmentation disorders, such as melasma, post-inflammatory hyperpigmentation, pigmentation changes due to skin aging, or any other skin conditions related with normal such as skin of color or abnormal pigmentation such as hypo- or hyper-pigmentation in humans. The compositions were generally applied to the affected skin area(s) either once daily in the evening (at least about half an hour before bedtime) or twice daily in the morning and in the evening. A sunscreen offering at least a sun protection factor of 15 (SPF15) (e.g., JOURNÉE Bio-restorative Day Cream by Neocutis Inc., San Francisco, Calif. 94123) was used during daytime to protect skin from sun. In case the compositions were also used at daytime, the subjects were instructed to apply the sunscreen after having applied the said compositions; preferentially at least half an hour after having applied the compositions.


The studies lasted at least three months (i.e., 12 weeks) and were continued over a longer period of time depending on severity of the skin pigmentation disorder. Epidermal melasma can be treated (i.e. skin pigmentation is visibly reduced at site of application) within about one to three months, whereas dermal melasma, mixed type melasma, post-inflammatory hyperpigmentation (e.g., hyperpigmentation originating after inflammation of skin such as related to skin burns, wounds, acne, use of certain medications, dermatitis, etc.), pigmentation changes due to skin aging (e.g., freckles, age or liver spots, etc.), or any other skin conditions related with normal such as skin of color (e.g., skin of individual with Hispanic, Asian, African or American/African origins), or abnormal pigmentation such as hypo- or hyper-pigmentation in humans may require generally at least a three month treatment period to see results (i.e. skin pigmentation is visibly reduced at site of application) when using compositions formulated in accordance with the present invention; eventually in combination with the use of a sunscreen product.


Results demonstrating the efficacy of the compositions formulated in accordance with the present invention are presented in FIG. 3.


Study with Composition Described in Example 1:


After a one month wash-out period where the subjects were allowed to only use JOURNÉE Bio-restorative Day Cream (offering SPF30+), the subjects applied the composition described in Example 1 twice daily (morning and evening) to their entire face after washing the face with a gentle skin cleanser (i.e., NEO-CLEANSE Gentle Cleanser by Neocutis). In the morning, they continued to use JOURNÉE Bio-restorative Day Cream.


Assessment of global melasma severity was performed by the investigator according to the following 4-point visual scoring system: 0=absent (color of the melasma lesions is close to that of surrounding skin; 1=mild (color is slightly darker than that of normal skin); 2=moderate (color is moderately darker); and 3=severe (color is markedly darker than surrounding normal skin). In addition, melasma was quantified with the help of the so-called MASI index (see Arch Dermatol 130, 1994, 727-733).


Three areas of the face were evaluated: forehead (F), malar region (M), and chin (C) corresponding to 30%, 60% and 10% of total face The involvement of melasma in the area of forehead, malar region, and chin were given a numerical value (AF, AM, AC): 0=no involvement; 1=less than 10% involvement; 2=10% to <30%; 3=30% to <50%; 4=50% to <70%; 5=70% to <90%; 6=90% to 100%. Severity was based on two factors: darkness (D) of melasma compared with normal skin; and homogeneity (H) of hyperpigmentation. Patients were assessed on a scale from 0 through to 4 as follows; the darkness (D) scale: 0=absent; 1=slight; 2=mild; 3=marked; 4=maximum; and the homogeneity (H) scale: 0=minimal; 1=slight; 2=mild; 3=marked; 4=maximum. To calculate the MASI score, the sum of the severity rating of darkness (D) and homogeneity (H) was multiplied by the numerical value of the respective areas involved (A) and by the various percentages of the three facial areas. These values were added to obtain the MASI score as follows: MASI=0.3(DF+HF)AF+0.6(DM+HM)AM+0.1(DC+HC)AC. Additionally, the number of age and liver spots were counted in face. Those evaluations were performed at the beginning of study (i.e., before wash-out period), after the one month wash-out period (i.e., before starting with the treatment with composition), and at the end of the study period (i.e., after 12 weeks of use of composition), respectively.













TABLE 22







Reduction in Global
Reduction in
Reduction in



Melasma Severity as
Melasma as
total Number



assessed by Investiga-
assessed by
of Age/Liver



tor Global Assessment
MASI-Scoring
Spots



















After one month
0 ± 0%
2 ± 3%
0 ± 0%


wash-out period


After 12 weeks
20 ± 27%
56 ± 33%
55 ± 22%


of use of


composition









Table 22 shows the efficacy of the composition described in Example 1 in treating skin pigmentation disorders and diseases. The average and standard deviation in the reduction from baseline (i.e., data before wash-out) from five female subjects who completed the study is shown in percentage (%) of reduction from baseline.


This study shows that the composition leads to a reduction in melasma severity and in the number (and intensity) of age or liver spots in face. Thus, the composition is effective for treating (i.e., reducing) symptoms of skin pigmentation disorders and diseases. The composition was further well tolerated. As further shown in this study, the use of a sunscreen (i.e., JOURNÉE Bio-restorative Day Cream) alone did not result in any significant reduction in symptoms of skin pigmentation disorders and diseases.


Study with Composition Described in Example 3:


The subjects applied the composition described in Example 3 once daily (evening) to either the right, or to the left side of their face (the side was randomly assigned) after washing the face with a gentle skin cleanser (i.e., Cetaphil by Galderma). In the morning, they additionally used JOURNÉE Bio-restorative Day Cream.


Assessment of global melasma severity was performed by the investigator according to the following 4-point visual scoring system: 0=absent (color of the melasma lesions is close to that of surrounding skin; 1=mild (color is slightly darker than that of normal skin); 2=moderate (color is moderately darker); and 3=severe (color is markedly darker than surrounding normal skin). In addition, melasma was quantified with the help of the so-called MASI index (Arch Dermatol 130, 1994, 727-733). Three areas of the face were evaluated: forehead (F), malar region (M), and chin (C) corresponding to 30%, 60% and 10% of total face; or 15%, 30% and 5% of half of the face, respectively. The involvement of melasma in the area of forehead, malar region, and chin were given a numerical value (AF, AM, AO: 0=no involvement; 1=less than 10% involvement; 2=10% to <30%; 3=30% to <50%; 4=50% to <70%; 5=70% to <90%; 6=90% to 100%. Severity was based on two factors: darkness (D) of melasma compared with normal skin; and homogeneity (H) of hyperpigmentation. Patients were assessed on a scale from


through to 4 as follows; the darkness (D) scale: 0=absent; 1=slight; 2=mild; 3=marked; 4=maximum; and the homogeneity (H) scale: 0=minimal; 1=slight; 2=mild; 3=marked; 4=maximum. To calculate the MASI score for a half-face (MASIHalf-Face), the sum of the severity rating of darkness (D) and homogeneity (H) was multiplied by the numerical value of the respective areas involved (A) and by the various percentages of the three facial areas. These values were added to obtain the MASI score as follows: MASI=0.15(DF+HF)AF+0.3(DM+HM)AM+0.05(DC+HC)AC. Those evaluations were performed at the beginning of study (i.e., before starting with the treatment with composition), and at the end of the study period (i.e., after 12 weeks of use of composition), respectively.












TABLE 23







Reduction in Global
Reduction in



Melasma Severity as
Melasma as



assessed by Investigator
assessed by



Global Assessment
MASI-Scoring


















After 12 weeks of
38 ± 37%
74 ± 20%


use of composition









Table 23 shows the efficacy of the composition described in Example 3 in treating skin pigmentation disorders and diseases. The average and standard deviation in the reduction from baseline (i.e., data before starting with the treatment with composition) from ten female subjects who completed the study is shown in percentage (%) of reduction from baseline.



FIG. 3 is a photograph showing the reduction of pigmentation in the skin of a patient using the compounds of the present invention (e.g. the composition described in Example 3). Panel A shows the hyperpigmentation of the patient's skin prior to administration of a compound of the present invention. Panel B shows the reduction in skin pigmentation following 12 weeks of treatment with a composition of the present invention.


The results of this study show that the composition leads to a reduction in melasma severity in treated area of face. Thus, the composition is effective for treating (i.e., reducing) symptoms of skin pigmentation disorders and diseases. The composition was further well tolerated.


Study with Composition Described in Example 2:


As shown in diverse in use studies, the composition obtained as described in Example 2 was also shown to be well tolerated and efficient in treating skin pigmentation disorders, such as melasma, post-inflammatory hyperpigmentation, pigmentation changes due to skin aging, or any other skin conditions related with normal such as skin of color or abnormal pigmentation such as hypo- or hyper-pigmentation in humans. Female and male human subjects were included in this study.


These studies demonstrated that the compositions obtained as described in Examples 1, 2 and 3 are effective for treating (i.e., reducing) symptoms of skin pigmentation disorders and diseases and are well tolerated under in use conditions.


Example 7

A human study showed that the composition described in Example 3 does not cause an acnegenic/comedogenic response. Thus, the use of this composition did not result in a significant increase in the number and severity of comedones/acne.


Prior to initiation of the study, each subject was examined and the facial skin condition, including counts of non-inflammatory and inflammatory lesions, were recorded. Severity of comedones/acne were determined by the following lesion count categories:


Grade I (mild)=Less than 10 comedones (including open: blackheads; closed: micropapules and whiteheads and/or inflammatory papulopustular lesions on one or both sides of the face.


Grade II (moderate)=10-25 comedones (including open: blackheads; closed: micropapules and whiteheads) and/or inflammatory papulopustular lesions on one or both sides of the face.


Grade III (severe)=More than 25 comedones (including open: blackheads; closed: micropapules and whiteheads) and/or inflammatory papulopustular lesions on one or both sides of the face.


Subjects were evaluated before and after four weeks of treatment (once daily in evening) with the composition. Differences between baseline and final dermatological evaluations were considered statistically significant, if the probability of obtaining the result by chance is less than or equal to 0.05 using analysis of variance and/or appropriate t-Test statistics. All assessments of facial skin condition and lesion counts were made by a Board Certified Dermatologist. The study was performed by an independent clinical research organization.


OTHER EMBODIMENTS

While the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims.

Claims
  • 1. A composition for treating or ameliorating at least one symptom of a skin pigmentation disorder or condition comprising at least one calcium sequestering or calcium binding agent.
  • 2. The composition of claim 1, wherein the at least one calcium sequestering or calcium binding agent is a phosphate free of calcium.
  • 3. The composition of claim 2, wherein the phosphate is glycerophosphoric acid or a non-calcium salt thereof.
  • 4. The composition of claim 3, wherein the phosphate is sodium glycerophosphate.
  • 5. The composition of claim 1, wherein the at least one calcium sequestering or calcium binding agent is present in an amount of about 0.1% to about 25% by weight.
  • 6. The composition of claim 2, wherein the phosphate free of calcium is present in an amount of about 1% to about 5% by weight.
  • 7. The composition of claim 1, wherein the composition further comprises at least one additional agent that modulates or regulates at least one step of melanogenesis.
  • 8. The composition of claim 7, wherein the at least one additional agent is selected from the group consisting of L-alanine, glycine, L-isoleucine, L-leucine, hydroquinone, 4-(1-phenylethyl) 1,3-benzenediol, arbutin, bearberry leaf extract, kojic acid, oxyresveratrol, gnetol, a melanosome transfer inhibitor, and an α-MSH antagonist.
  • 9. The composition of claim 1, wherein the composition further comprises at least one skin moisturization and skin rejuvenation agent.
  • 10. The composition of claim 9, wherein the skin moisturization and skin rejuvenation agent is selected from the group consisting of ascorbic acid, vitamin E, jojoba oil, shea butter, human fibroblast lysate, retinoic acid, retinol, and any derivatives thereof.
  • 11. The composition of claim 1, wherein said composition is suitable for topical administration to a subject in need thereof.
  • 12. The composition of claim 1, wherein said composition is in the form of a solution, an oil-in-water emulsion, a water-in-oil emulsion, a gel, an ointment, a patch, a paste, a liquid, a foam, a mousse, a spray, an aerosol, a triple emulsion, a nanoemulsion, a microemulsion, a hydrogel, a jelly, a dispersion, a suspension, and a tape.
  • 13. The composition of claim 1, wherein said composition is substantially free of calcium.
  • 14. The composition of claim 1, wherein said composition is stable, does not cause an acnegenic or comedogenic response, and produces minimal skin irritation in said subject.
  • 15. A method of treating or ameliorating a skin pigmentation disorder comprising administering an effective amount of the composition of claim 1 to a patient suffering therefrom.
  • 16. The method of claim 15, wherein the skin pigmentation disorder is selected from the group consisting of melasma, post-inflammatory hyper-pigmentation, pigmentation changes due to skin aging, age or liver spots, freckles, hypo-pigmentation, and hyper-pigmentation.
  • 17. The method of claim 15, wherein the patient is a human.
  • 18. The method of claim 15, wherein the composition is administered to the patient topically.
  • 19. The method of claim 15, wherein, following administration, the composition reduced skin pigmentation in the patient.
  • 20. A pharmaceutical formulation comprising the composition of claim 1 and at least one pharmaceutically acceptable carrier.
  • 21-32. (canceled)
RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 12/688,107, filed Jan. 15, 2010 which claims priority to U.S. Ser. No. 61/145,325, filed Jan. 16, 2009, both of which are herein incorporated by reference in their entirety.

Provisional Applications (1)
Number Date Country
61145325 Jan 2009 US
Continuations (1)
Number Date Country
Parent 12688107 Jan 2010 US
Child 14794462 US