United States Patent [19]
`Sun et al.
`
`US006042845A
`[11] Patent Number:
`[45] Date of Patent:
`
`6,042,845
`*Mar. 28, 2000
`
`54 ANTI FUNGAL TREATMENT OF NAILS
`
`P '
`y E ' —S
`l B
`rzmar xamzner amue arts
`
`[75] Inventors: Ying Sun, Somerville; Jue-Chen Liu,
`Neshanic; Elizabeth S. Kimbleton,
`princ?itoné Jonas C- T- Wang,
`Robbmsvlne’ an of NJ’
`[73] Assignee; Johnson & Johnson Consumer
`Products, Inc., Skillman, N].
`
`[57]
`
`ABSTRACT
`
`There is disclosed a method for the treatment of fungal
`diseases in nails, Which comprises the topical administration
`to the nail and, if desired, also to the surrounding skin, of (1)
`a sulfhydryl containing amino acid or a derivative thereof,
`
`[ *1 Notice
`'
`
`the pharmaceutically acceptable salts or esters thereof, or
`This atent issued on a Continued ms
`stereoisomers thereof, (2) urea, (1) and (2) being adminis
`ecutiopn application ?led under 37 PCFR
`tered in an amount suf?cient to enhance the permeation of
`1,53(d), and is subject to the twenty year
`Patent term Provisions of 35 USC antifungal drugs through nail tissue, either prior to or,
`154(aX2)‘
`preferably, concurrently With the topical administration to
`[21] AppL NO‘: 08/922,041
`the nail of (3) an effective amount of an antifungal drug.
`'
`Th'ld'ldbdgdpdfhp'l
`ere 1s aso 1scose a an a e a ate ort e to ica
`[22] Flled:
`administration of medication to the nail, said bandage com
`prising a T-shaped adhesive backing, and a ?exible pad
`having an impervious backing and a nail-shaped cavity
`backed by said impervious backing, Wherein said nail
`shaped cavity contains absorptive means having absorbed
`therein urea and a sulfhydryl Containing amino acid or a
`derivative thereof, a pharmaceutically acceptable salt or
`ester thereof, or a stereoisomer thereof.
`
`Sep‘ 2’ 1997
`Related US Application Data
`
`[63] g’tntglgagzggflzgplication Now/361741371360 22’ 1994’
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`........................ .. A61L 15/16
`[51] Int. Cl. ..
`ffijtgséaszf
`[52] US‘
`’
`514/252 562
`’
`[58] Field of Searc’h
`514/588, 946, 947, 953, 399; 424/446,
`447, 448
`
`5 Claims, 17 Drawing Sheets
`
`CFAD Exhibit 1005
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`U.S. Patent
`
`Mar. 28,2000
`
`Sheet 17 0f 17
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`6,042,845
`
`FIG. 13A
`
`18
`
`

`
`6,042,845
`
`2
`reaction that occurs betWeen the disul?de bonds in nail
`keratin and a thiol-containing compound (in this case,
`cysteine) is shoWn in the folloWing scheme:
`
`1
`ANTI FUNGAL TREATMENT OF NAILS
`
`This is a continuation, of application Ser. No. 08/361,
`413, ?led Dec. 22, 1994, Which is hereby incorporated by
`reference now US. Pat. No. 5,696,164.
`The invention relates to a method for the topical treat
`ment of fungal diseases in nails, and more particularly, to a
`composition and a method for enhancing the permeation rate
`of antifungal agents in nails. The invention also relates to a
`bandage adapted for use With the method of the invention.
`
`5
`
`CO
`
`CO 3
`
`BACKGROUND OF THE INVENTION
`
`Although signi?cant progress has been made in the devel
`opment of antifungal drugs, nail fungal infection (e.g.,
`onychomycosis) remains a disease most difficult to treat.
`The target sites for the treatment of onychomycosis reside in
`the nail plate, nail bed and nail matrix (see FIG. 1). Topical
`treatment has not been effective because antifungal drugs
`cannot readily penetrate the nail plate to reach the infection
`sites under the nail. Oral administration of antifungal drugs
`is the only effective Way to treat onychomycosis, Which has
`limited the use of some of the more potent antifungal drugs
`such as itraconaZole and ketoconaZole because of concern
`for possible side effects. It has been shoWn, hoWever, that if
`the nail barrier can be overcome or eliminated, topical
`antifungal drug treatment can be effective. For example,
`both miconaZole and ketoconaZole Were demonstrated to be
`effective in topically treating onychomycosis after nail avul
`sion. There is a need for a methodology for topical nail
`fungal treatment that does not require removal of the nail.
`Such topical treatment Would then permit the use of the more
`potent antifungal drugs in the treatment of fungal-infected
`nails.
`
`The nail plate is too thick and too dense for drugs to
`penetrate at a practical rate. Although nail is similar to
`stratum corneum of the skin in that it is derived from
`epidermis, it is mainly composed of hard keratin (highly
`disul?de-linked) and is approximately 100-fold thicker than
`stratum corneum. In order to deliver a sufficient amount of
`drug into the nail plate, the permeability of the nail plate to
`the drug needs to be enhanced. The permeation-related
`properties of the nail differ from those observed in stratum
`corneum primarily in three respects: (a) the total lipid
`content of the nail is much less than the lipid content of
`stratum corneum; (b) the nail has a high sulphur content
`(cystine) in its hard keratin domain Whereas the stratum
`corneum does not; (c) under average conditions, the nail
`contains much less Water than the stratum corneum.
`
`The chemical composition of nail and experimental evi
`dence indicate that the aqueous pathWay plays a dominant
`role in drug penetration into nail. Water is the principal
`plasticiZer for the nail. Upon being hydrated, hard nail plates
`become softer and more ?exible. Nail hydration is in?u
`enced by many factors, such as solution pH and certain
`chemicals. Keratolytic agents, such as urea and salicylic acid
`are often used to soften nail plates. Urea and a combination
`of urea and salicylic acid Were reported to be used for
`nonsurgical avulsion of nail dystrophies in clinical studies
`prior to topical treatment of onychomycosis With satisfac
`tory results.
`Nail plates have high sulphur content in the form of
`disul?de bonds. Certain reducing agents, e.g., cysteine or a
`derivative thereof, can break the disul?de bond in keratin to
`increase the ability of the nail to hydrate. The chemical
`
`15
`
`25
`
`35
`
`45
`
`55
`
`This invention provides a delivery means for topical
`treatment of fungal diseases of the nail Which delivers an
`effective dose of drug to (a) the diseased nail plate (and
`consequently, the underlying nail bed), of Which the hydra
`tion capability has been signi?cantly increased to enhance
`drug permeability (nail route); and (b) the surrounding skin
`tissues, including nail bed and matrix via the eponychium
`and hyponychium (skin route—see FIG. 1).
`
`BRIEF SUMMARY OF THE INVENTION
`
`The invention provides a method for the treatment of
`fungal diseases in nails, Which comprises the topical admin
`istration to the nail and, if desired, also to the surrounding
`skin, of (1) a sulfhydryl containing amino acid or a deriva
`tive thereof, the pharmaceutically acceptable salts or esters
`thereof, or stereoisomers thereof, (2) urea, (1) and (2) being
`administered in an amount sufficient to enhance the perme
`ation of antifungal drugs through nail tissue, either prior to
`or, preferably, concurrently With the topical administration
`to the nail of (3) an effective amount of an antifungal drug.
`The invention also provides a composition comprising (1),
`(2) and (3), as described above.
`The invention further provides a bandage adapted for the
`topical administration of medication to the nail, said ban
`dage comprising a T-shaped adhesive backing, and a ?exible
`pad having an impervious backing and a nail-shaped cavity
`backed by said impervious backing, Wherein said nail
`shaped cavity contains absorptive means having absorbed
`therein urea and a sulfhydryl containing amino acid or a
`derivative thereof, a pharmaceutically acceptable salt or
`ester thereof, or a stereoisomer thereof.
`
`THE PRIOR ART
`
`65
`
`The reduction reaction betWeen keratin disul?de bonds
`and thioglycolates are frequently utiliZed in the cosmetic
`industry, e.g., for cold Waving and depilatory of hair, and
`enhancing cosmetic appearance of the nail.
`
`19
`
`

`
`3
`Olthoff et al., in EP 440298 A1, disclose the use of
`sulfur-containing amino acid derivatives in topical prepara
`tions for treatment of nail diseases such as onychomycosis.
`KaWase et al (EP 472858 A2 Mar. 4, 1992) describe a hair
`treatment composition containing siloXanes and penetration
`enhancers such as ammonium thioglycolate, Which gives the
`treated hair a good gloss and a reduced number of hair splits.
`Puri (WO 8600013 A1 Jan. 3, 1986) discloses that the
`condition of hair, skin and nails is improved by treatment
`With an aqueous ammonium thioglycolate solution, folloWed
`by treatment With a protein hydrolyZate.
`Rothman (WO 8907930 A1 Sep. 8, 1989) describes a
`storage-stable protein-containing composition and a method
`for treating keratinous tissues. The protein-containing com
`position contains reducing agents such as ammonium
`thioglycolate. The composition is said to be useful for
`conditioning horny keratinous tissues of mammals such as
`human hair and nail, and the hooves and fur of animals, to
`improve their strength and appearance and to promote hair
`and nail groWth.
`An enhanced transdermal drug permeation in rats has
`been reported for theophylline
`Kushida et al., Chem.
`Pharm. Bull., 32, 1 (1984) 268—274] and insulin
`Sun et
`al., Ann. NeW York Academy of Sciences, 1990, 596; Y. Sun
`et al., Proceed. Intern. Sym. Control. Rel. Bioactive Mat., 17
`(1990) 202; and J. C. Liu et al., in Drug Permeation
`Enhancement: Theory and Applications, p247—272, (D. S.
`Hsieh, Ed.) Marcel Dekker, Inc., 1994] by pretreating the
`skin With aqueous calcium thioglycolate solution. On the
`other hand, direct addition of calcium thioglycolate into an
`ointment containing the calcium salt of indomethacin dra
`matically decreased the absorption of the drug [T. Ogiso et
`al., J. Pharmcobio-Dyn., 9 (1986) 517—525].
`Konno et. al. (EP 152281 A2 Aug. 21, 1985) describes a
`transdermal formulation of nicardipine hydrochloride con
`taining urea and thioglycol.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 shoWs the treatment target sites of a fungus
`infected nail;
`FIG. 2 is a graph displaying the effect of area on nail
`sWelling using aqueous urea solutions of various concentra
`tions at pH 4.5;
`FIG. 3a is a graph shoWing comparisons of the nail
`sWelling enhancement among several thiol-containing
`amino acid and analogs after nail clippings Were immersed
`in the formulation at 32° C. for 48 hours;
`FIG. 3b is a graph shoWing comparisons of the partition
`ing of itraconaZole into nail among several thiol-containing
`amino acid and analogs after nail clippings Were immersed
`in the formulation at 32° C. for 48 hours;
`FIGS. 4a, 5a and 6a are graphs shoWing the effect of
`N-acetyl-1-cysteine and urea on nail sWelling in different
`formulations;
`FIGS. 4b, 5b and 6b are graphs shoWing the effect of
`N-acetyl-1-cysteine and urea on itraconaZole partitioning
`into nail in different formulations;
`FIG. 7 is a graph shoWing nail sWelling and miconaZcle
`nitrate partitioning into nail in a miconaZole nitrate cream
`formulation;
`FIG. 8 is a graph shoWing the nail sWelling—pH pro?le
`With nail clippings immersed in a formulation containing
`urea, propylene carbonate, propylene glycol, N-acetyl-1
`cysteine and Water, at differing pH values;
`FIG. 9 is a graph shoWing the permeation pro?les of
`itraconaZole from three formulations With various compo
`sitions;
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`55
`
`60
`
`65
`
`6,042,845
`
`4
`FIG. 10 is a graph shoWing the amount of itraconaZole
`penetrated through the nail plate, as Well as the amount
`retained in the nail plate, for three different formulations;
`FIG. 11 is a graph shoWing the permeation pro?le of
`miconaZole nitrate through the nail plate for three formula
`tions;
`FIG. 12 is a graph that shoWs the amount of miconaZole
`nitrate penetrated through the nail plate, as Well as the
`amount retained in the nail plate, for three formulations; and
`FIG. 13 shoWs three vieWs of a device designed for
`topical drug delivery to nails.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`The invention relates to a method for the treatment of
`fungal diseases in nails, Which comprises the topical admin
`istration to the nail of (1) a sulfhydryl containing amino acid
`or a derivative thereof, the pharmaceutically acceptable salts
`or esters thereof, or stereoisomers thereof, (2) urea, (1) and
`(2) being administered in an amount suf?cient to enhance the
`permeation of antifungal drugs through nail tissue, either
`prior to or, preferably, concurrently With the topical admin
`istration to the nail of (3) an effective amount of an anti
`fungal drug.
`The term “nail” means the horny cutaneous plate on the
`dorsal surface of the distal end of a ?nger or toe. FIG. 1 is
`a schematic diagram shoWing the basic anatomic structure of
`human nail and its surrounding tissues. The topical antifun
`gal drug treatment for nail fungal disease (onychomycosis)
`contemplated by this invention is intended to deliver anti
`fungal drug to the nail plate (the stratum corneum unguis)
`and to the nail bed (the modi?ed area of epidermis beneath
`the nail, over Which the nail plate slides as it groWs) through
`the nail plate. Desirably, antifungal drug is also concurrently
`administered to the nail matrix (the proXimal portion of the
`nail bed from Which groWth chie?y proceeds) and nail bed
`through the skin of the eponychium (commonly called the
`cuticle) and the hyponychium (the thickened epidermis
`underneath the free distal end of the nail).
`The topical treatment of the invention may be employed
`in combination With systemic treatment With an antifungal
`drug such as griseofulvin or other antifungal drug that can be
`given orally over long periods of time, either concurrently
`during the entire systemic treatment regimen, or concur
`rently during a portion (usually the latter phase) of the
`systemic treatment regimen, or folloWing such systemic
`treatment.
`The fungal diseases of the nail that can be treated in
`accordance With the invention are those that are called
`“onychomycosis”, Which is usually an infection by Epider
`mophyton ?occosum, several species of Trichophyton, or
`Candida albicans.
`The antifungal drugs that can be used in the invention
`include miconaZole nitrate, ketoconaZole, itraconaZole,
`?uconaZole, econaZole, terconaZole, saperconaZole,
`amorol?ne, ciclopiroX, oXiconaZole, clotrimaZole,
`terbina?ne, nafti?ne, and other antifungal drugs that are
`available in a topical formulation. The preferred antifungal
`drugs for use in the process of the invention are itraconaZole,
`ketoconaZole and miconaZole nitrate. If desired, the topical
`formulation containing the antifungal drug may include an
`agent such as hydroXypropyl-[3-cyclodeXtrin that enhances
`the Water-solubility of the antifungal drug, in order to better
`utiliZe the aqueous pathWay through the nail, as discussed
`above. The anti-fungal drugs are used in anti-fungally effec
`tive amounts. For example, anti-fungally effective amounts
`
`20
`
`

`
`6,042,845
`
`5
`are usually from about 0.5% to about 10%, by weight, and
`preferably from about 1% to about 5%, by weight, of the
`formulation that is applied to the nail or surrounding dermal
`tissue.
`
`Urea is employed in the invention. It is believed that
`urea’s principal contribution to the efficacy of the formula-
`tion used in tlie invention is to inhibit the nail keratin from
`returning to its original densely packed cross—linked state
`(such return to the original densely packed cross—linked state
`would be caused by oxidation from the oxygen in the
`atmosphere), so that the nail remains more permeable to the
`antifungal drug over a longer period of time. (The ability of
`urea to inhibit the nail keratin from returning to its original
`densely packed cross—linked state probably stems from
`urea’s ability to disrupt non—covalent interactions in nail
`keratin.) One beneficial effect of the use of urea is that the
`sulfhydryl-containing amino acid or derivative thereof can
`be used in a lower concentration, thereby reducing (although
`probably not eliminating) the potential of the amino acid or
`derivative thereof for irritation of the skin.
`
`The invention employs a sulfhydryl containing amino
`acid or a derivative thereof, the pharmaceutically acceptable
`salts or esters thereof, or stereoisomers thereof. Such com-
`pounds can be represented by Formula (I):
`
`Hs—(CH2),,
`
`H——R
`NHRi
`
`(1)
`
`the pharmaceutically acceptable salts or esters thereof,
`and stereoisomers thereof,
`wherein:
`
`R=H, CONHCHZCOOH, NH2 or COORZ wherein R2
`is H or C1_4alkyl;
`R1=H, COCH3, CONH2, or CO(CH2)mCH(NH2)
`(COOH) wherein m is 1 or 2; and
`n=a number having a value of from 1 to 4.
`Illustrative examples of compounds of Formula (I)
`include those shown in the following table:
`
`TABLE 1
`
`Cysteine (1-cysteine, d-cysteine, d1-cysteine)
`
`IISTCII2—CIITCOOII
`
`NH;
`
`N-Acetyl-1-cysteine
`
`HSTCH2—CH—COOH
`NH
`
`(|:OCH3
`d1-Homocysteine
`
`IIS:CII2—CII2—CII:COOII
`
`NI-I1
`
`1-Cysteine methyl ester (methyl cysteine)
`
`IIS—CII2—CIIiCOOCII2
`
`NH;
`
`6
`
`TABLE l—continued
`
`1-Cysteine ethyl ester (ethyl cysteine)
`
`HS:CHg—CH'—COOCHzCH3
`
`NI-I2
`
`N-Carbamoyl cysteine
`
`HS:CH2—CH: COOH
`NI-I
`
`Co—NH2
`
`Glu ta thione
`
`cnZ—sn
`
`Hc—Co.\IHcH2CooH
`
`NHCOCH2CH2CHNH2
`COOH
`
`Cysteamine
`HS—CHZ—CH2—NH2
`
`The preferred compounds for use in the invention are
`N-acetyl-1-cysteine and cysteine.
`The urea and the sulfhydryl-containing amino acid or
`derivative thereof are employed in amounts sulficient to
`enhance the permeation of antifungal drugs through nail
`tissue. Thus, the topical composition that is applied to the
`nail will ordinarily contains from about 1% to about 50%,
`and preferably from about 5% to about 20%, (by weight)
`urea, and from about 0.1% to about 40%, and preferably
`from about 3% to about 20%, (by weight) of the sulfhydryl-
`containing amino acid or derivative thereof, the percentages
`being based upon the total weight of the fomiulation being
`applied to the nail. The pH range of the formulation is
`usually from about pH 2 to pH 10, and preferably from about
`pH 3 to pH 8.
`
`EXPERIMENTAL
`a. Effect of Nail Penetration Enhancers on Nail Swelling and
`Drug Partitioning into Nail
`The ability of a drug in a formulation to penetrate nail
`plate should be reflected by the rate and extent of the nail
`uptake of the formulation (i.e., nail swelling in the
`formulation), as well as by the amount of the drug migration
`into the nail (drug partitioning into nail). In vitro experi-
`ments were conducted to examine the e ect of drug formu-
`lation containing nail penetration enhancer on nail swelling
`and drug partitioning.
`The experimental procedure was the following: Clean
`human nail clippings were equilibrated to a constant weight
`by placing them in a desiccator over saturated CaCl2~6II2O
`solution (29% relative humidity at room temperature) for at
`least 48 hours before use. Approximately 30 mg of human
`nail clippings were weighed into a glass vial. The exact
`initial weight was recorded. Four grams of the test formu-
`lation (pre-warmed to 32° C.) was added into the vial and
`maintained at 32° C. under stirring in a Heating/Stirring
`Module (Reacti—Therm III, Pierce). The changes in nail
`weights were monitored at predetermined intervals over 48
`hours. At the end ofthe swelling experiment, the nail sample
`was rinsed with a mixture of N,N—dimethylformamide and
`methanol ( 1:1)
`to remove surface-bound drug. The nail
`
`21
`
`

`
`6,042,845
`
`7
`sample was then digested, and the drug concentration in nail
`was determined by high pressure liquid chromatography
`method as described by Badcock and Davies, Assay of
`itraconazole in nail clippings by reversed phase, high per-
`formance liquid chromatography, Ann. Clin. Biochem, 27
`(1990) 506-508.
`Several terms were used to describe the data. The nai
`swelling was expressed by the percentage of the initial nai
`weight (i.e., 100% of the initial nail weight means no
`swelling, and 200% means a nail swelling doubling the
`original weight, etc). An enhancement factor is used to show
`the increase in nail swelling due to the presence of nai
`penetration enhancer in comparison to the control, which
`were calculated according to the formula: enhancemen
`factor=(”/n weight gain of the test nail sample)/(% wcigh
`gain of control nail sample, i.e., no enhancer & urea in the
`formulation). Similarly,
`the enhancement factor for
`the
`enhanced itraconazole partitioning into nail is defined as:
`enhancement factor=(drug concentration in the test nai
`sample)/(drug concentration in the control nail sample). The
`drug concentration in nail was calculated by dividing the
`amount of the drug in nail (mg) by the weight of the initia
`nail clipping (i.e., dry nail weight in gram). This expression
`of drug nail concentration is used herein unless specifiec
`otherwise.
`The effect of urea on nail swelling was investigated, using
`aqueous urea solutions of various concentrations at pH 4.5.
`The graph shown as FIG. 2 shows that as urea concentration
`increased from 20% to 40%, nail hydration increased from
`30% to 50%. For this reason, it is believed that the use of
`urea alone will not cause significant enhancement of drug
`permeation through the nail.
`TABLE I, above, shows the names and chemical struc-
`tures of the thiol-containing amino acids and derivatives
`thereof that were investigated. To examine the eflects of
`these nail penetration enhancers on nail swelling and drug
`
`8
`itraconazole and miconazole nitrate
`partitioning, several
`formulations were prepared with an enhancer in each for-
`mulation (TABLE 2, below, displays the formulations). In
`the control experiment, there was no penetration enhancer
`(“E”) or urea (“U”) in the formulation. In the experiments
`discussed below,
`the following abbreviations and com-
`pounds were used:
`Ac Cyst=N-acetyl-1-cysteine
`Cysteine=1—cysteine
`Homocyst=d1-homocysteine
`Cysteam=cysteamine
`MethylCy=1-cysteine methyl ester
`EthylCyst=l-cysteine ethyl ester
`Itra=itraconazole
`
`Repl:nd=replenished every n days
`SA=salicylic acid (keratolytic agent; pH control)
`PG=propylene glycol (solvent)
`PC=propylene carbonate (solvent)
`EDTA=etl1yler1edian1ine tetraacetic acid (disodium salt—
`chelating agent)
`KLUCEL=hydroxypropylcellulose thickener)
`BHT=butylated hydroxy toluene (anti—oxidant)
`Mic.Nit.=miconazole nitrate
`
`BHA=Butylated hydroxyanisole
`Labrifil M 1944 CS=Unsaturated polyglycolized glycer-
`ides obtained by partial alcoholysis of apricot kernel oil,
`consisting of glycerides and polyethylene glycol esters—an
`amphiphilic oil, solvent and/or emulsifier.
`TEFOSE 63=Ethylene glycol and polyoxyethylene glycol
`palmitostearate; CTFA adopted name is PEG 6 stearate (and)
`PEG-32 stearate (and) glycol stearate—a non-ionic self-
`emulsifying base for oil/water emulsioned preparations.
`
`FORMULATIONS
`
`IN WEIGHT‘ %
`
`TABLE 2
`
`ENPLXNCER
`
`ITRA ENHANCER SA UREA PC
`
`PG
`
`0
`10
`10
`10
`10
`10
`
`(.3VA
`
`I»(4)u.U|
`L»>(..)bJU|U|Ut
`
`
`
`U~)l.A)(2~)(r)b~)b~1l.m)(A~)bJ(r)v)(2~)§NUI‘.l|UIU|U|Vt’J|U|VtU|'J|UIU|
`
`-J:-.l>-J:.l:-_cr\_o_a\_<:\<:CJC><3.J>..J>.J>.¢>..J:-J>-tsUIUVJIUI
`
`‘IIan0
`Lnuum
`
`kII‘.I|UIOU\U\’J\®<3C>C>®UI
`
`moounutooutunoounLnUnutunun<:
`
`vi
`
`-40-5
`No E&U
`-33-3
`Ac Cyst
`-34-1
`Cysteine
`-34-2
`Homocyst
`5 -34-3
`Cysteam
`-34-4
`MelhylCy
`' -34-5
`EthylCys
`5 -40-1
`No Ac&U
`5 -40-2
`No AL:
`-40-3
`No U
`-23
`Ac-#23
`5 -40-4
`No Ac&U
`-33-1
`‘.70 No Ac
`-33-2
`No U
`5 -26
`Ac-#26
`-40-5
`No Ac&U
`805--33-4
`No Ac
`8054 -33-5
`No U
`8054-33-3
`Ac-#33-3
`ITRACONAZOLE
`NAIL Pl:'RMEAl'I()l\
`
`’
`
`Repl:3d
`Replzld
`Repl:1d
`
`2138-41
`2138-136
`2138-137
`
`EDTA BHT KLCCEL
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`0.05
`
`OOOOOGOOCOOOOOOCOOC
`
`H20
`47.85
`27.85
`27.85
`27.85
`27.85
`27.85
`27.85
`51.85
`31.85
`46.85
`26.85
`45.35
`30.35
`35.35
`25.35
`47.85
`32.85
`37.85
`27.85
`
`TOTAL
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`98
`
`2435*
`26.85
`30.85
`
`100
`100
`100
`
`22
`
`

`
`6,042,845
`
`FORMULATIONS
`
`TABLE 2—continued
`
`IN WEIGI-IT %
`
`ENHANCER
`
`ITRA ENHANCER SA UREA PC
`
`PG
`
`EDTA BHT KLUCEL
`
`MICONAZOLE NITRATE
`NAIL PERMEATION
`
`2138-69
`2138-70
`2138-70
`
`Rcpl:3d
`Repl:3d
`Repl:7d
`‘Includes 0.1% ascorbic acid.
`
`FIG. 3a shows a comparison of the nail swelling enhance-
`ment effect and FIG. 3b shows a comparison of the itra-
`conazole partitioning enhancement effect of the thiol-
`containing amino acids and derivatives thereof of nail
`clippings after immersion in the test formulations at 32° C.
`for 48 hours.
`the thiol-
`The results in the FIG. 3a show that all
`containing amino acid and derivatives thereof investigated
`increased nail swelling in the itraconazole formulations,
`with the enhancement factors ranging from 1.82 to 4.57. The
`highest nail swelling enhancement was found with
`l—cysteine, followed by N—acetyl—l—cysteine and cysteamine.
`As shown in FIG. 3b, tl1e sanie rank order was observed
`among the penetration enhancers for their ability in enhanc-
`ing itraconazole partitioning into nail. The drastic increase in
`itraconazole migration into the nafl (approximately 100-
`fold) indicates that incorporation of the penetration enhancer
`into a topical itraconazole formulation will definitely facili-
`tate the antifungal drug reaching its target sites in the nail
`plate and the nail bed.
`The graphs displayed in FIGS. 441-60 and 417-619 show the
`elfect of N-acetyl-1-cysteine as penetration enhancer, and
`
`urea as adjuvant synergist on the nafl swelling and itracona-
`zole partitioning. The compositions of the formulations are
`tabulated in Table 3, below. All three itraconazole formula-
`tions contain 1% itraconazole, 5% N—acetyl—1—cysteine, and
`di erent concentration of urea and other components. The
`pH of these formulations was adjusted to 3.0. As can be seen
`from these figures, by adjusting the composition of a
`formulation, one can obtain the desired performance from
`the formulation, as reflected by nail swelling and itracona-
`zole partitioning. The benefit of incorporating urea into the
`formulations is demonstrated by a clear trend shown in
`4a—6a and 4b—6b. As can be seen, the increase of itracona-
`zole partitioning into nail owing to the presence of urea is
`higher than the increase of nail swelling in all three formu-
`lations.
`
`TABLE 3
`
`FORMULATIONS
`
`ENHANCER
`
`SVVELLING ("/0 wt x 100)
`AVG
`STD
`Enh. F
`
`ITRA PARTITIONING (rn
`AVG
`ST 3
`E
`
`No E&U
`Ac Cyst
`Cysteine
`Ilomocyst
`Cysteani
`Metl1ylCy
`EthylCys
`No Ac&U
`No Ac
`No U
`Ac-#23
`l\ 0 Ac& U
`No Ac
`No U
`Ac-#26
`No AL'& U
`No A:
`No U
`Ac-#33-3
`
`8054-40-5
`8054-33-3
`8054-34-1
`8054-34-2
`8054-34-3
`8054-34-4
`8054-34-5
`8054-40-5
`8054-40-2
`8054-40-3
`8054-23
`8054-40-4
`8054-33-1
`8054-33-2
`8054-26
`8054-40-5
`8054-33-4
`8054-33-5
`8054-33-3
`
`1.35
`2.11
`2.59
`1.71
`2.06
`1.73
`1.64
`1.43
`1.43
`3.32
`3.61
`1.36
`1.42
`1.80
`2.06
`1.35
`1.52
`1.90
`2.11
`
`0.01
`0.04
`0.03
`0.05
`0.01
`0.04
`0.05
`0.03
`0.06
`0.23
`0.39
`0.06
`0.05
`0.06
`0.06
`0.01
`0.02
`0.06
`0.04
`
`1
`3.18
`4.57
`2.04
`3.03
`2.09
`1.82
`1
`1.01
`5.45
`6.12
`1
`1.18
`2.26
`2.97
`1
`1.5
`2.57
`3.18
`
`0.047
`4.365
`4.897
`1.097
`2.632
`1.430
`1.221
`0.061
`0.068
`0.990
`0.853
`0.059
`0.670
`2.132
`3.293
`0.047
`0.940
`2.281
`4.365
`
`>->—x
`
`0.0
`0.52
`.C >_x »\::o>—n
`0.23
`0.18
`Lnkp>—lO
`0.07
`0.2
`0.03
`0.03
`0.40
`0.1
`0.0
`0.15
`0.09
`0.30
`0.0
`0.167
`0.339
`0.520
`
`>—nLpL/ukplutqun
`
`U\t\>>—t\o>—n
`Lp>—k>—\>—\>—‘>—k>—kbJLp
`
`on
`
`\oJ>-Mu
`
`PERME/5nTI()l\
`
`ITRACONAZOLE IN NAIL
`
`ITRACONAZOLE
`NAIL PERMEATION
`
`Repl:3d
`Repl:1d
`Repl:1d
`
`2138-41
`2138-136
`2138-137
`
`(ug/cniz)
`AVG
`
`22.28
`49.05
`0.00
`
`STD
`
`8.66
`31.79
`0.00
`
`(ug/cmz)
`AVG
`
`.
`. 6
`.
`
`STD
`
`.
`.
`5. 2
`
`(ug/cnij *)
`AVG
`
`1096.5
`691.6
`221.9
`
`STD
`
`516.1
`230.1
`138.4
`
`23
`
`

`
`11
`
`6,042,845
`
`TABLE 3—continued
`PERMEATION
`MICONAZOLE NITRATE IN NAIL
`
`MICONAZOI F. NITRATF.
`NAII, PFRMEATTOV
`
`(lug/cm’)
`AVG
`
`STD
`
`(u.ycn1))
`AVG
`
`(u.g/cur‘ *)
`AVG
`
`221654
`99384
`99998
`
`2138-69
`2138-70
`2138-70
`
`4484
`1889
`1431
`
`Repl:3d
`Rcpl:3d
`Rcpl:7d
`‘Calculation based on the initial volume of the untreated nail.
`‘jug/cm3 = ;zg’cm2 /nail thickness (cm)
`
`952
`278
`147
`
`11215
`4924
`6001
`
`Anail swelling and drug partitioning experiment was also
`conducted for miconazole nitrate using procedures analo-
`gous to those described above. The graphed results shown in
`FIG. 7 show tl1at, similar to itraconazole data, significant
`nail swelling coincided with substantial miconazole parti-
`tioning into the nail, using the following formulation:
`1% Miconazole nitrate, 0.005% BHA, 1.5% heavy n1in-
`eral ofl, 1.5% peglicol 5 oleate (LABRAFIL M 1944 CS),
`10% pegoxol 7 stearate (TEFOSE 63), 0.05% EDTA, 20%
`urea, 10% N-acetyl-1-cysteine, and 55.9% Water, with pH
`adjusted to 9.0 with NaOH, as required.
`It should be noted that, unlike the itraconazole formula-
`tions discussed above, which Were tested at pH 3, the pH
`value of the miconazole nitrate formulation was set at pH 9.
`The significant nail swelling and coinciding high
`miconazole-nail partitioning indicate that N-acetyl-1-
`cysteine has a wide worldng pH range. This was confirmed
`by the swelling-pH profile shown in FIG. 8, using the
`following formulation:
`20% urea, 35% propylene carbonate, 10% propylene
`glycol, 10% N-acetyl-1-cysteine and 25% water, with pH
`adjusted with HCl or NaOH, as required, to pH 3.2, 4.0, 5.0,
`6.0 and 7.0. The experimental temperature was 32° C.
`b. E ect of Nail Penetration Enhancers on Drug Permeation
`Through Nail and the Drug Retention and Distribution in the
`Nail Plate
`the enhancement effect of N-acetyl-1-cysteine
`To test
`containing itraconazole formulation,
`itraconazole perme-
`ation experiments were conducted using human cadaver
`nails. Briefly, a nail plate was mounted on a nail dilIusion
`cell (exposed nail area=0.1202 cmz)
`in which the nail
`separated a donor chamber from a receptor chamber. The /
`donor chamber was then charged with an itraconazole for-
`mulation of 100-200 mg. To simulate the clinical situation,
`the drug formulation in the donor chamber was removed,
`and replenished with fresh drug formulation according to a
`predetermined time schedule. The solution in the receptor _
`chamber was 20% aqueous hydroxypropyl—[3—cyclodextrin
`(5 n1l, pH 4) to ensure sink conditions. [“Sink condition” is
`defined as a condition wherein the concentration of the
`
`permeant (in this case, itraconazole) in the receptor solution
`is lower than 10% of its solubility in the receptor solution—
`the idea is to drive the equilibrium such that the permeation
`of the permeant into the receptor solution is favored.