HK1174270B - Compositions and methods for stimulating hair growth - Google Patents

Description

FIELD OF THE INVENTION

The present invention relates to compositions for stimulating the growth of hair. The compositions can be used to treat disorders involving hair loss.

BACKGROUND OF THE INVENTION

Dermatologists recognize many different types of hair loss, the most common being "alopecia" or "baldness" wherein humans (mostly males) begin losing scalp hair at the temples and on the crown of their head. However, hair loss may be due to many other disorders.

Hair loss is often accompanied by a change in the hair growth cycle. All mammalian hair passes through a life cycle that includes the anagen phase, the catagen phase and the telogen phase. The anagen phase is the period of active hair growth. In the scalp, this phase lasts from 3-5 years. The catagen phase is a short 1-2 week transitional phase between the anagen phase and the telogen phase. The final telogen phase is considered a "resting phase" where all growth ceases. This phase is also relatively short-lived lasting about 3-4 months before the hair is shed and a new one begins to grow. With the onset of baldness, a successively greater proportion of hairs are in the telogen phase with correspondingly fewer in the active growth anagen phase.

Additionally, different types of hair exist including terminal hairs, vellus hairs and modified terminal hairs. Terminal hairs are coarse, pigmented, long hairs in which the bulb of the hair follicle is seated deep in the dermis. Vellus hairs, on the other hand, are fine, thin, non-pigmented short hairs in which the hair bulb is located superficially in the dermis. Modified terminal hairs are seen in eye lashes and eye brows. As alopecia progresses, a transition takes place wherein the hairs themselves change from the terminal to the vellus type. Accordingly, alopecia (baldness) also includes a deficiency in terminal hairs

One non-drug treatment for alopecia is hair transplantation. Plugs of skin containing hair are transplanted from areas of the scalp where hair is growing to bald areas. This approach can be reasonably successful; however it is costly, time-consuming and painful. Other non-drug related approaches to treating alopecia include ultra-violet radiation, massage, psychiatric treatment and exercise therapy. None of these approaches, however, have been generally accepted as effective. Even such things as revascularization surgery or acupuncture have shown little, if any, effect.

US 2008/0070988 A1 discloses a hair-growth composition comprising bimatoprost and absolute alcohol, and discloses compositions comprising bimatoprost and propylene glycol.

SUMMARY OF THE INVENTION

An aspect of the present invention is a composition suitable for growing hair by topical application, the composition comprising bimatoprost and one or more penetration enhancers, wherein the composition comprises glycerol monooleate as a penetration enhancer.

In an embodiment, bimatoprost is contained in the composition at a concentration of about 0.001 - 1.5% w/w, from 0.01 - 1.0% w/w, 0.02 - 1.0% w/w, 0.03 to about 1.0% w/w, 0.03 - 0.9% w/w, 0.04 - 0.8% w/w, 0.05 - 0.7% w/w, 0.06% - 0.6% w/w, 0.07% - 0.5% w/w, 0.08 - 0.4% w/w, 0.09 - 0.3% w/w, 0.1 % w/w, 0.2% w/w, 0.3% w/w, 0.4% w/w, 0.5% w/w, 0.6% w/w, 0.7% w/w, 0.8% w/w, 0.9% w/w or 1.0% w/w. The following excipients maybe also be included: Carbomer at a concentration of about 0.05 - 1.0 % w/w; base at a concentration of about 0.01 to about 2.0 % w/w; ethanol at a concentration of about 10 to about 90 % w/w; glycerin at a concentration of about 1.0 to about 20 % w/w; diethylene glycol monoethyl ether at a concentration of about 1.0 to about 50 % w/w; polysorbate 20 at a concentration of about 0.1 to about 5.0 % w/w; polysorbate 40 at a concentration of about 0.1 to about 5.0 % w/w; polysorbate 60 at a concentration of about 0.1 to about 5.0 % w/w; polysorbate 80 at a concentration of about 0.1 to about 5.0 % w/w; PPG-5 ceteth-20 at a concentration of about 0.1 to about 5.0 % w/w; oleic acid at a concentration of about 0.1 to about 5.0 % w/w; isostearyl isostearate at a concentration of about 0.1 to about 10 % w/w; isopropyl myristate at a concentration of about 0.1 to about 10 % w/w; dipropylene glycol dimethyl ether at a concentration of about 1 to about 50 % w/w; diethylene glycol at a concentration of about 1 to about 50 % w/w; dipropylene glycol at a concentration of about 1 to about 50 % w/w; caprylic/capric at a concentration of about 0.1 to about 10 % w/w; benzyl alcohol at a concentration of about 0.1 to about 2.0 % w/w; silicone at a concentration of about 0.1 to about 10 % w/w; and/or water at a concentration of about 0 to about 90 % w/w.

The composition can be manufactured using a general procedure in which non-aqueous components (e.g. bimatoprost, ethanol, glycols) are combined in a beaker and stirred using a propeller type overhead mixer until the solution is clear, water is added to the non-aqueous mixture followed by the addition of a polymeric thickening agent, and, upon dispersion of the thickening agent, a base is added to neutralize the polymer and thicken the solution into a gel other desired composition.

Another aspect of the invention is a composition as defined above for use in a therapeutic method of treating a hair loss disorder in a mammal by topical administration of the composition.

A further aspect of the invention is a non-therapeutic method for stimulating hair growth in a mammal, the method comprising topical application of a composition as defined above.

DETAILED DESCRIPTION

Bimatoprost is a moderately soluble compound intended for topical delivery to the skin to stimulate hair growth. Hair growth includes, without limitation, stimulating the conversion of vellus hair to growth as terminal hair as well as increasing the rate of growth of terminal hair. The composition of the invention comprises bimatoprost and one or more penetration enhancers which include glycerol monooleate. The penetration enhancers facilitate active component penetration and/or maintenance at their site of action in the skin. Formulations disclosed herein can be self-preserved or contain an antimicrobial agent such as benzyl alcohol.

The active compound is cyclopentane N-ethyl heptanamide-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, [1_α,2_β,3_α,5_α], also known as bimatoprost and sold under the name of LUMIGAN® by Allergan, Inc., California, USA. This compound has the following structure:

The synthesis of the above compound has been disclosed in U.S. Pat. No. 5,607,978 .

Effective amounts of bimatoprost can be determined by one of ordinary skill in the art, but will vary depending on the frequency of application and desired result. The amount will generally range from about 1 x 10^-7 to about 50% w/w of the composition, in one embodiment from about 0.001 to about 50% w/w of the composition and in another embodiment from about 0.1 to about 30% w/w of the composition. Ranges of about 10-50% w/w, about 20-50% w/w and about 30-40% w/w, and an amount of about 35% are also included.

The pharmaceutical formulations disclosed herein include one or more penetration enhancers. The phrase "penetration enhancers" includes any agent that facilitates the transfer of active components to their site of action or maintains them at their site of action. Non-limiting examples of classes of appropriate penetration enhancers include alcohols, glycols, fatty acids, ethers, esters, occlusive agents and surface active agents. Representative examples of these classes are provided below.

Alcohols include, without limitation, ethanol, propanol, N-propanol, isopropanol, butyl alcohol, octanol, benzyl alcohol and acetyl alcohol, in one embodiment, as described in U.S. Pat. No. 5,789,244 . Fatty alcohols include, for example, stearyl alcohol and oleyl alcohol.

Glycols include, without limitation, glycerine, propyleneglycol, polyethyleneglycol and other low molecular weight glycols such as glycerol and thioglycerol.

Fatty acids, esters and ethers include, besides glycerol monooleate, oleic acid, palmitoleic acid, straight chain C₄-C₂₀ saturated monocarboxylic and dicarboxylic acids, octanoic and decanoic acids, methyl laurate, ethyl oleate, polyethylene glycol monolaurate, propylene glycol monolaurate, propylene glycerol dilaurate, glycerol monolaurate, isopropyl n-decanoate, octyldodecyl myristate, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether and compounds wherein a C₂-C₄ alkane diol or triol is substituted with one or two fatty ether substituents.

Occlusive agents include, without limitation, silicones, mineral oils and greases, long chain acids, animal fats and greases, vegetable fats and greases, water insoluble polymers, paraffin, paraffin oil, liquid paraffin, petrolatum, liquid petrolatum, white petrolatum, yellow petrolatum, microcrystalline wax and ceresin.

Surface active agents include without limitation, polysorbate 20, 40, 60 and 80, TWEEN® (20, 40, 60, 80), POLOXAMER® (231, 182, 184), sodium dodecyl sulfate (SDS), lecithin, lysolecithin, nonylphenoxypolyoxyethylene, lysophosphatidylcholine, polyethylenglycol 400, polyoxyethylene ethers, polyglycol ether surfactants, DMSO, sodium laurate, sodium lauryl sulfate, cetyltrimethylammonium bromide, and benzalkonium chloride.

Additional penetration enhancers will be known to those of ordinary skill in the art of topical drug delivery, and/or are described in the pertinent texts and literature.

Embodiments disclosed herein can also include viscosity increasing agents. Appropriate agents include, without limitation, methylcellulose, polyvinyl alcohol, polyvinyl pyrrolidone, hyaluronic acid and chondroitin sulfate.

Certain embodiments disclosed herein can include preservatives including, without limitation, benzyl alcohol, benzalkonium chloride, chlorhexidine, chlorobutanol, methyl-, propyl-, or butyl- parahydroxybenzoic acids, phenylmercuric salts including, without limitation, nitrate, chloride, acetate, and borate, and betaine.

Various other additives may be included in the compositions of the present invention in addition to those identified above. These include, but are not limited to, antioxidants, astringents, perfumes, emollients, pigments, dyes, humectants, propellants, and sunscreen agents, as well as other classes of materials whose presence may be cosmetically, medicinally or otherwise desirable. The compositions and formulations may also be taken in conjunction with minoxidil and propecia.

Compositions can also be formulated as "slow-releasing" formulations so that the activity of active components is sustained for a longer period of time between treatments.

While particular embodiments disclosed herein can include each of the components discussed above, other particular embodiments can be required to be "substantially free" of one or more of these components in various combinations. "Substantially free", as used herein, means that the component is not added to a formulation and cannot be present in any amount greater than about 1% w/w.

While not limiting the scope of express exclusion of the preceding paragraph, particular embodiments disclosed herein can be substantially free of one or more of bimatoprost, carbomer, NaOH (s), TEA, ethanol, glycerin, diethylene glycol, monoethyl ether, propylene glycol, polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 80, PPG-5 ceteth-20, oleic acid, isostearyl isostearate, isopropyl myristate, dipropylene glycol dimethyl ether, diethylene glycol, dipropylene glycol, triglycerides, caprylic/capric, benzyl alcohol, silicone and water.

All components of formulations described herein will be included in amounts that are dermatologically acceptable. As used herein, "dermatologically acceptable" means that the compositions or components thereof are suitable for use in contact with human skin without undue toxicity, incompatibility, instability, allergic response, and the like. As used in herein as applied to active agents and excipients, the term "about" refers to variations in concentrations which are considered to be bioequivalent.

Embodiments disclosed herein find application in mammalian species, including both humans and animals. In humans, the compounds of embodiments disclosed herein can be applied without limitation, to the scalp, face, beard, head, pubic area, upper lip, eyebrows, and eyelids. The compositions of the present inventions may be used for treating various hair loss disorders including but not limited to alopecia areata, telogen effluvium, anagen effluvium, cicatricial alopecia and scarring alopecia; hair shaft abnormalities such as trichorrexis nodosa, loose anagen syndrome, trichotillomania and traction alopecia; infectious hair disorders such as tiniea capitis, sebohorreic dermatitis, and follicullitus of the scalp; genetic disorders such as androgenetic alopecia and patients undergoing hair loss due to chemotherapy, hormonal imbalance (e.g., thyroid conditions such as hypothyroidism and hyperthyroidism, pregnancy, child birth, discontinuation of birth control pills and changes in menstrual cycle), fungal infection of the scalp such as ringworm, medicines which cause hair loss such as anti-coagulants, medicine for gout, depression, high blood pressure and certain heart medications. The formulations of the present invention may be used to treat hair loss related to other disease such as diabetes, lupus, and poor nutrition, mental and physical stress such as due to surgery, illness and high fever. Hair loss may be due to environmental factors and chemicals used in hair treatment (dying, tinting and bleaching).

In animals raised for their pelts, e.g., mink, the formulations can be applied over the entire surface of the body to improve the overall pelt for commercial reasons. The process can also be used for cosmetic reasons in animals, e.g., applied to the skin of dogs and cats having bald patches due to mange or other diseases causing a degree of alopecia.

The compositions and methods of the present invention may be applied to patients suffering from hair loss or in healthy patients simply wanting to increase hair growth in any part of the body.

The compositions disclosed herein are formulated for topical administration. The term "topical administration" as used herein includes applying a formulation as described herein to the outer skin or hair. The application will generally occur at or near the area of desired hair growth.

Accordingly, appropriate formulation or composition types include, without limitation, solutions, gels, ointments, foams, films, liniments, creams, shampoos, lotions, pastes, jellies, sprays and aerosols. Such formulation types can be applied in swaths, patches, applicators or through the use of impregnated dressings depending on the situation and part of the body to be treated.

Typically, the formulations described herein will be applied repeatedly for a sustained period of time to the part of the body to be treated. In particular embodiments, formulations disclosed herein can include one or more applications daily, one or more applications weekly, one or more applications monthly or one or more applications yearly for a period of treatment of at least one day, at least one week, at least one month, at least one year or until the treatment has achieved or achieved and maintained a desired result.

Formulations described herein will be administered in safe and effective amounts. As used herein, "safe and effective amounts" include an amount sufficient so that the composition provides the desired hair growth stimulation effect at a reasonable benefit/risk ratio attendant with any medical treatment. Within the scope of sound medical judgment, the amount of active components used can vary with the particular condition being treated, the severity of the condition, the cause of the condition, the duration of the treatment, the specific active component employed, its concentration, the specific vehicle utilized, the general health of the patient, the tolerance of the patient to various effects of the administration, other drugs being administered to the patient, and like factors within the specific knowledge and expertise of the patient or attending physician.

For daily administration, an appropriate dose can include, without limitation, about 0.1 ng to about 100 mg, about 1 ng to about 10 mg per day or in another embodiment about 10 ng to about 1 mg per day.

Non-limiting examples of some components with their appropriate concentration ranges and function are provided in Table 1 below. Table 1: Example Components with Function and Concentration Ranges

bimatoprost	Active	0.03 - 1.0
carbomer	Thickener	0.05 - 1.0
base	Neutralizing Agent	0.01 - 2.0
ethanol		10-90
glycerin		1.0 - 20
diethylene glycol monoethyl ether		1.0 - 50
propylene glycol		1 - 50
polysorbate 20		0.1 - 5.0
polysorbate 40		0.1 - 5.0
polysorbate 60		0.1 - 5.0
polysorbate 80	Penetration enhancers	0.1 - 5.0
PPG-5 ceteth-20		0.1 - 5.0
oleic acid		0.1 - 5.0
isostearyl isostearate		0.1 - 10
isopropyl myristate		0.1 - 10
dipropylene glycol dimethyl ether		1 - 50
diethylene glycol		1 - 50
dipropylene glycol		1 - 50
caprylic/capric triglycerides		0.1-10
benzyl alcohol	Preservative	0.1 - 2.0
silicone	Occlusive Agent	0.1 - 10
water	Vehicle	0-90

REFERENCE EXAMPLES EXAMPLE I. Preparations of Bimatoprost Scalp Hair Growth Gel Compositions

Ethyl alcohol is weighed into a suitable media jar equipped for mixing, and bimatoprost is then added to the ethyl alcohol and stirred at moderate speed until the bimatoprost is dissolved. Into a separate mixing tank, water for injection, glycerin, diethylene glycol monoethyl ether, and propylene glycol are added and mixed until the solvents are dispersed. The ethyl alcohol/bimatoprost solution is then added into the water mixture and mixed until the components are homogenously mixed (about 5 minutes of mixing). To the mixture the carbomer thickener is added and mixed until well dispersed. Once dispersed a base is added to thicken the solution into a gel. Representative formulations made according to the method above are shown in Table 2 below. Table 2: Bimatoprost Scalp Hair Growth Topical Gel Formulations

Bimatoprost	Active	0.03	0.1	0.3	0.2
Propylene glycol	Penetration enhancer	10.0	10.0	10.0	10.0
Diethylene glycol monoethyl ether		10.0	10.0	10.0	10.0
Ethyl alcohol		30.0	30.0	30.0	30.0
Glycerin		2.0	2.0	2.0	2.0
Carbomer (Ultrez 10)	Thickener	0.15	0.15	0.15	0.15
Triethanolamine	Neutralizing agent	0.16	0.16	0.16	0.16
Purified water	Vehicle	47.66	47.59	47.39	47.49

EXAMPLE II. In Vivo Treatment

A study is initiated to systematically evaluate the appearance of hair on the scalp and eyebrows administered with bimatoprost gel formulations as in Table 2. The study involves 10 subjects, 5 male, 5 female, average age 70 years, (ranging from 50-94 years). Each subject is treated daily by the topical application of bimatoprost by the 0.3% w/w bimatoprost formulation of Table 2.

The study is limited to subjects who have administered bimatoprost for more than 3 months. The mean duration of exposure to the 0.3% w/w bimatoprost gel formulation prior to assessing the parameter of hair or eyebrow growth between the control and study eye is 129 days (range 90-254 days). Observations are made under high magnification at a slit lamp biomicroscope. Documentation of differences between the control and treatment areas is accomplished using a camera specially adapted for use with a slit lamp biomicroscope.

The results of the observations will be as follows:

Length of hair and eyebrows: Increased length of hair in both groups is regularly observed. The difference in length varies from approximately 10% to as much as 30%.

Number of hairs: Increased numbers of hairs are observed on the scalp and eyebrows of each patient. The difference in number of hairs varies from approximately 5% to as much as 30%. Whether statistically significant or not, bimatoprost with a penetration enhancer will provide better and/or faster results than bimatoprost without a penetration enhancer.

The foregoing observations will establish that 0.03% w/w bimatoprost composition penetrates skin and grows hair.

Claims (6)

1. A composition suitable for growing hair by topical application, the composition comprising bimatoprost and one or more penetration enhancers, wherein the composition comprises glycerol monooleate as a penetration enhancer.
2. A composition according to Claim 1, which is in the form of a solution, a gel, an ointment, a foam, a film, a liniment, a cream, a shampoo, a lotion, a paste, a jelly, a spray or an aerosol.
3. A composition according to Claim 1 or Claim 2 for use in a therapeutic method of treating a hair loss disorder in a mammal by topical administration of the composition.
4. A composition for use according to Claim 3, wherein the method comprises applying the composition at least once daily to the scalp.
5. A composition for use according to Claim 3 or Claim 4, wherein the hair loss disorder is selected from alopecia areata, telogen effluvium, anagen effluvium, cicatricial alopecia, scarring alopecia, a hair shaft abnormality such as trichorrexis nodosa, loose anagen syndrome, trichotillomania and traction alopecia, an infectious hair disorder such as tiniea capitis, sebohorreic dermatitis and follicullitus of the scalp, and androgenetic alopecia.
6. A non-therapeutic method for stimulating hair growth in a mammal, the method comprising topical application of a composition as defined in Claim 1 or Claim 2.