# Patent

## Title
Wax foamable vehicle and pharmaceutical compositions thereof

## Abstract

Unique foamable vehicles or carriers comprising at least one wax, waxy substance, counterpart or derivative, a stabilizer, water, and a propellant are provided. In some embodiments, the wax is a liquid wax. In some embodiments, the wax includes a solid wax and a liquid wax. The compositions are substantially free of crystals. The components are selected to provide a composition that is substantially resistant to aging and to phase separation, and/or can substantially solubilize and or stabilize active ingredients. Pharmaceutical and cosmetic compositions with potentially enhanced skin delivery and their uses are also provided.

## Background
This application is a continuation of and claims the benefit of priority to U.S. application Ser. No. 12/187,840 filed Aug. 7, 2008, which claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 60/954,525 filed Aug. 7, 2007, entitled “Wax Foamable Vehicle And Pharmaceutical Compositions Thereof”, which is incorporated in its entirety by reference.


BACKGROUND
This invention relates to foamable pharmaceutical and cosmetic compositions.
External topical administration is an important route for the administration of drugs in disease treatment. Many groups of drugs, including, for example, antibiotic, anti-fungal, anti-inflammatory, anesthetic, analgesic, antiallergic, corticosteroid, retinoid and anti-proliferative medications are preferably administered in hydrophobic media, namely ointment. However, ointments often form an impermeable barrier, so that metabolic products and excreta from the wounds to which they are applied are not easily removed or drained away. Furthermore, it is difficult for the active drug dissolved in the carrier to pass through the white petrolatum barrier layer into the wound tissue, so the efficacy of the drug is reduced. In addition, ointments and creams often do not create an environment for promoting respiration of the wound tissue and it is not favorable to the normal respiration of the skin. An additional disadvantage of petroleum jelly-based ointments and creams relates to the greasy feeling left following their topical application onto the skin, mucosal membranes and wounds.
Foams are considered a more convenient vehicle for topical delivery of active agents. There are several types of topical foams, including aqueous foams, such as commonly available shaving foams; hydroalcoholic foams, emulsion-based foams, comprising oil and water components, and oleaginous foams, which consist of high oil content. In skin therapy, oil containing foams are preferred, since oil contributes to skin protection and moisturization, which improve the therapeutic effect of the formulation.
Fatty acids and fatty alcohols counterparts and derivatives have been used in foamable formulations as foam adjuvants usually in low amounts of up to about 5% and may possibly have a therapeutic effect in the treatment of a variety of skin disorders and/or conditions. Some are waxy solids while others are liquid at room temperature and pressure. For example, in the case where the carbon backbone chain is 18C, stearic acid and stearyl alcohol are waxy solids whilst isostearic acid, oleic acid and oleyl alcohol are liquids. The significance of this difference in liquidity of molecules having the same or similar backbone chain on foamable compositions is investigated herein.
Jojoba oil has been used in foamable formulations usually in relatively low amounts of up to about 10% and may possibly have a therapeutic effect in the treatment of a variety of skin disorders and/or conditions.
Branched (i.e., non-straight chain) waxes like oleic acid are known to contribute to the skin penetration of an active agent.
Aldara, a commercially available topical cream containing imiquimod as active agent, uses 25% isostearic acid as a solubilizing agent.
Formulations comprising micronized imiquimod with fatty acids and fatty alcohols are known. The level of fatty acid in such formulations, however, is minimized to avoid idiosyncrasy. As such, these formulations are essentially free of isostearic acid. Moreover, such formulations are cream formulations and foam compositions of such formulations have not been specifically disclosed.
Emulsion based foam formulations comprising imiquimod and fatty acids in sufficient amount to solubilize imiquimod have been disclosed. These formulations are limited in the amount of isostearic acid that can be present in the formulation (typically 25% or less).
Aqueous foam compositions comprising partially neutralized fatty acids as organic solvents have been generally disclosed in the art. However, specific compositions containing additional components, such as polymers, surfactants, and liquid fatty acids have not been disclosed. The stability of such foams relies upon the presence of a component such as triethanolamine, as well as basic active components (such as imiquimod) to neutralize fatty acid and water foams.
Foam using very high amounts of anionic surfactants 20% to 95% with C10:0 (e.g., 1-decanol) fatty alcohol has been described in the art. The large amounts of surfactant result in a mesomorphic phase which solubilizes the propellant. The use of high levels of anionic surfactants and C10:0 fatty alcohol, which are irritants, renders these compositions unsuitable for use on the skin and eyes, and, in some cases, harmful, particularly in the eyes.
There remains an unmet need for improved, easy to use, vehicles and foam formulations, comprising wax, waxy substances, counterparts and derivatives thereof in preferably in substantial or higher concentrations which can effectively deliver and/or deposit various active agents into and onto the skin and/or other target sites and are relatively non-irritating and thus suitable for use by people having sensitive skin, body cavities and mucosal surfaces. Significantly there remains an unmet need for such vehicles and foam formulations that are substantially free from crystals. Accordingly, in some embodiments, the formulations described herein are free from crystals. In some embodiments, the formulations are free from an insoluble phase or, in some embodiments, free from insoluble matter. The presence of crystals indicates that one or more ingredients are not solubilized. In consequence amongst other things the formulation may be unstable, may be variable, may deliver unreliable amounts of active ingredients and may cause irritation and thus be unsuitable for therapeutic use. Additionally substantial crystal formation in a foamable formulation may interfere with foam release. In some embodiments, the formulations are free from crystals yet still include a suspension of solid matter or particles. In some embodiments, the solid matter or particles are not crystalline. Examples of such solid matter include, without limitation, microsponges, ground seed, metallic particles and active agents in particle form (e.g., benzyl peroxide).
There is a need for such vehicles and foam formulations in which there is a relatively low level of surfactants. Surfactants can be irritants particularly at higher levels. Repeated use of formulations with higher levels of surfactants on the skin can result in depletion of hydrophobic substances and dry skin.
High levels of surfactant can result in the formation of a mesomorphic phase. The mesomorphic phase can absorb propellant and may increase irritation, depletion of fats and dry skin. There is a need for such vehicles and foam formulations in which there is no mesomorphic phase
SUMMARY
The present invention relates to aqueous wax emulsion compositions.
In one aspect, foamable compositions are provided which include (a) a wax, (b) a stabilizer component, (c) water, and (d) a propellant. In some embodiments, the wax is a liquid wax. In other embodiments, the wax is a combination of a solid wax and a liquid wax. In some embodiments, the wax, for example the liquid wax or the solid wax, includes at least one fatty acid or at least one fatty alcohol. In some embodiments, when the liquid wax includes at least one fatty acid, the fatty acid is present in the composition at a concentration of at least about 35% by weight. In some embodiments, when the liquid wax includes at least one fatty alcohol, the fatty alcohol is present in the composition at a concentration of at least about 12% by weight. In some embodiments, when the composition includes a solid wax, the solid wax is present in the composition at a concentration of at least about 7% by weight. In one or more embodiments all the ingredients are dissolved. In further embodiments the composition is substantially free from crystals, e.g., free of an insoluble phase. Assessing whether a composition is free from crystals or free of an insoluble phase is performed by techniques known to those of skill in the art. One exemplary technique for assessing the presence of crystals or an insoluble phase in the compositions described herein is by visual inspection, e.g., using light microscopy, as described in further detail herein. In some embodiments the composition includes at least one active agent. In certain embodiments the active agent is soluble in the composition.
In one aspect, foamable compositions are provided which include (a) jojoba oil, (b) a stabilizer component, (c) water, and (d) a propellant. In some embodiments, the jojoba oil is present in the composition at a concentration of at least about 10% by weight.
In some embodiments, the stabilizer component includes a non-ionic surface active agent, a polymeric agent or a mixture of a non-ionic surface active agent and a polymeric agent. Exemplary polymeric agents include, without limitation a bioadhesive agent, a gelling agent, a film forming agent and a phase change agent. In some embodiments, the polymeric agent is present in the composition at a concentration of about 0.01% to about 5% by weight.
In some embodiments, the propellant is a liquefied hydrocarbon gas propellant. In some embodiments, the ratio of the combination of the wax, the stabilizer component and the water to the propellant is about 100:3 by weight to about 100:35 by weight.
In some embodiments, the composition is substantially free from crystals and is substantially flowable.
In some embodiments, the foamable composition is stored in a pressurized container. Upon release from the pressurized container, the resulting foam is breakable.
In one aspect, a foamable composition is provided that includes:
a. a liquid wax including at least one fatty acid or at least one fatty alcohol;
b. a stabilizer component including a non ionic surface-active agent, a polymeric agent or a mixture thereof;
c. water; and
d. a liquefied hydrocarbon gas propellant, wherein the ratio of the liquid wax, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight.
When the liquid wax includes at least one fatty acid, the fatty acid is present in the composition at a concentration of at least about 35% by weight. When the liquid wax includes at least one fatty alcohol, the fatty alcohol is present in the composition at a concentration of at least about 12% by weight. The composition is substantially free from crystals and is substantially flowable. When the stabilizer component includes a polymeric agent, the polymeric agent is present in the vehicle composition at a concentration of about 0.01% to about 5% by weight. The polymeric agent is a bioadhesive agent, a gelling agent, a film forming agent or a phase change agent. Upon release from a pressurized container, the foam produced is breakable.
In an embodiment the composition further includes a solid wax.
In another aspect, a foamable composition is provided that includes
a. at least about 7% by weight of a solid wax;
b. a liquid wax wherein the liquid wax includes at least one fatty acid or at least one fatty alcohol
c. a stabilizer including a non ionic surface-active agent, a polymeric agent or a mixture thereof;
d. water; and
e. a liquefied hydrocarbon gas propellant, wherein the ratio of the solid wax, the liquid wax, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight.
The composition is substantially free from crystals and is substantially flowable. When the stabilizer component includes a polymeric agent, the polymeric agent is present in the vehicle composition at a concentration of about 0.01% to about 5% by weight. The polymeric agent is a bioadhesive agent, a gelling agent, a film forming agent or a phase change agent. Upon release from a pressurized container, the foam produced is breakable.
In some embodiments, the composition includes at least one liquid fatty acid. The liquid fatty acid is present in the composition at a concentration of at least about 35% by weight. In some embodiments, the composition includes at least one liquid fatty alcohol. The liquid fatty alcohol is present in the composition at a concentration at least about 12% by weight.
In one or more embodiments the wax foamable compositions further include an active agent.
In a further aspect, a foamable composition is provided that includes:
a. at least about 10% by weight jojoba oil;
b. a stabilizer component including a surface-active agent, a polymeric agent or a mixture thereof;
c. water; and
d. a liquefied hydrocarbon gas propellant, wherein the ratio of the component, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight.
The composition is substantially free from crystals and is substantially flowable. When the stabilizer component includes a polymeric agent, the polymeric agent is present in the vehicle composition at a concentration of about 0.01% to about 5% by weight. The polymeric agent is a bioadhesive agent, a gelling agent, a film forming agent or a phase change agent. Upon release from a pressurized container, the foam produced is breakable.
In one or more embodiments the jojoba foamable composition further includes an active agent.
In some embodiments, there are provided vehicles and foam formulations in which the hydrophobic wax is liquid wax. In particular, in some embodiments, there are provided formulations where the wax includes a liquid fatty acid. Similarly there are provided in some embodiments formulations where the wax includes a liquid fatty alcohol. In other embodiments, there are further provided formulations where the liquid wax includes at least one fatty acid and at least one fatty alcohol. The fatty wax is present in the composition at a concentration of at least about 30 wt %; at least about 35 wt %; at least about 40 wt %; at least about 50 wt %; or at least about 60 wt %. The fatty alcohol is present in the composition at a concentration of at least about 7.5 wt %; at least about 10 wt %; at least about 20 wt %; at least about 30 wt %; at least about 40 wt %; at least about 50 wt %; or at least about 60 wt %.
In some embodiments, there are provided vehicles and foam formulations in which the hydrophobic wax is a combination of liquid wax and solid wax where the solid wax is at least about 7 wt %; at least about 10 wt %; at least about 20 wt %; at least about 30 wt %; or at least about 40 wt %.
In some embodiments, there are provided vehicles and foam formulations in which there is a high level of fatty acids. For example, in some embodiments the fatty acids are in excess of about 30%; in excess of about 40%; in excess of about 50%; or in excess of about 60% by weight of the formulation.
In some embodiments, there are provided vehicles and foam formulations in which there is a high level of fatty acids and fatty alcohols combined. For example, in some embodiments, the fatty acids and fatty alcohols are in excess of about 35%; in excess of about 37%; in excess of about 40% in excess of about 50%; and in excess of about 60%; by weight of the formulation.
In some embodiments, there are provided vehicles and foam formulations in which there is a high level of fatty acids and or fatty acids and fatty alcohols combined together with a non basic active agent (e.g., a neutral active agent or an acidic active agent). For example, in some embodiments, the fatty acids alone or combined with fatty alcohols are in excess of about 30%; in excess of about 35%; in excess of about 40%; in excess of about 50%; and in excess of about 60%; by weight of the formulation. By “non basic active agent” is meant an active agent that when present in a therapeutically effective amount does not cause a significant amount of neutralization of an acid formulation. By significant is intended to be about 20% or more neutralization.
In some embodiments, there are provided vehicles and foam formulations in which there is a high level of fatty acids alone or fatty acids and fatty alcohols combined wherein one of the fatty acids is solid and the presence of liquid wax enables the solid wax to solubilize at high concentrations. For example, in some embodiments, the fatty acids and fatty alcohols are in excess of about 37%; in excess of about 40%; in excess of about 50%; or in excess of about 60% by weight of the formulation.
In some embodiments, there are provided vehicles and foam formulations in which the amount of jojoba oil is more than 10% by weight of the formulation.
In some embodiments, there are provided vehicles and foam formulations in which the wax, stabilizer and water and amounts thereof generate an emulsion that is substantially resistant to phase reversal.
In some embodiments, there are provided vehicles and foam formulations in which the polymer or the polymeric agent is a polymeric surfactant.
In one or more embodiments any of the vehicles and foam formulations described herein also include an active agent. In some embodiments the formulations include at least one other active agent (i.e., two or more active agents in the composition).
In some embodiments, there is also provided a formulation of any of the compositions described above wherein the composition is in a non foam state.
In some embodiments, there is also provided a formulation of any of the compositions described above for use in the manufacture of a medicament.
In one aspect, a method of treating, ameliorating or preventing a disorder of a mammalian subject is provided. The method includes administering any of the compositions described herein to a target site.


DETAILED DESCRIPTION
The present invention relates to an aqueous composition comprising wax for use as vehicle, therapeutic, cosmetic or pharmaceutical composition.
According to one or more embodiments, the composition includes: a pharmaceutical or cosmetic vehicle composition comprising:

    
    
        a. at least one hydrophobic wax selected from the group consisting of a liquid wax, a solid wax and mixtures thereof;
        b. at least one stabilizer selected from the group consisting of a surface-active agent, a polymeric agent and mixtures thereof; and
        c. water,
    
    


wherein the vehicle is substantially free from crystals and is substantially flowable.
According to one or more embodiments, the hydrophobic wax comprises a liquid wax and a solid wax, wherein the liquid wax concentration in relation to the solid wax concentration is effective to dissolve any solid wax crystals in the composition. In an embodiment the composition further comprises a liquefied hydrocarbon gas propellant, wherein the ratio of the wax, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight, wherein upon release from a pressurized container the composition expands to form a breakable foam.
According to one or more embodiments, the composition includes: a foamable composition comprising:
a. a liquid wax comprising at least one fatty acid or at least one fatty alcohol;
b. a stabilizer component comprising a non ionic surface-active agent, a polymeric agent or a mixture thereof;
c. water; and
d. a liquefied hydrocarbon gas propellant, wherein the ratio of the liquid wax, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight;
wherein, when the liquid wax comprises at least one fatty acid, the fatty acid is present in the composition at a concentration of at least about 35% by weight and wherein, when the liquid wax comprises at least one fatty alcohol, the fatty alcohol is present in the composition at a concentration of at least about 12% by weight;

wherein the composition is substantially free from crystals and is substantially flowable;

wherein, when the stabilizer component comprises a polymeric agent, the polymeric agent is present in the vehicle composition at a concentration of about 0.01% to about 5% by weight and includes a bioadhesive agent, a gelling agent, a film forming agent and a phase change agent; and

wherein, upon release from a pressurized container, the foam produced is breakable.

In an embodiment the composition further comprises a solid wax.
According to one or more embodiments, the composition includes: a foamable composition comprising
a. at least about 7% by weight of a solid wax;
b. a liquid wax wherein the liquid wax comprises at least one fatty acid or at least one fatty alcohol
c. a stabilizer comprising a non ionic surface-active agent, a polymeric agent or a mixture thereof;
d. water; and
e. a liquefied hydrocarbon gas propellant, wherein the ratio of the solid wax, the liquid wax, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight;
wherein the composition is substantially free from crystals and is substantially flowable;
wherein, when the stabilizer component comprises a polymeric agent, the polymeric agent is present in the vehicle composition at a concentration of about 0.01% to about 5% by weight and includes a bioadhesive agent, a gelling agent, a film forming agent and a phase change agent; and

wherein, upon release from a pressurized container, the foam produced is breakable.

In one or more embodiments when the composition comprises at least one liquid fatty acid, the liquid fatty acid is present in the composition at a concentration of at least about 35% by weight and when the composition comprises at least one liquid fatty alcohol, the liquid fatty alcohol is present in the composition at a concentration at least about 12% by weight.
According to one or more embodiments, the polymeric agent is about 0.01% to about 5% by weight and is selected from the group consisting of a bioadhesive agent, a gelling agent, a film forming agent and a phase change agent;
According to one or more embodiments, the wax, stabilizer and water are selected to provide a composition that satisfies one, two, three, four or all of the following
a) substantially resistant to aging;
b) substantially resistant to phase separation;
c) substantially resistant to phase reversal;
d) can substantially stabilize or solubilize active ingredients; or
e) can improve skin penetration.
In one embodiment a) to e) above are satisfied.
In one or more embodiments the composition is contained in a pressurized container and further comprises a liquefied hydrocarbon gas propellant. In one or more embodiments, the composition provides a foam upon release. In one or more embodiments, the composition and/or the foam is substantially flowable. In some embodiments, the wax, stabilizer, solvent and propellant are selected to generate a breakable foam of good to excellent quality.
In one embodiment the propellant is added to the total amount of composition, wherein the ratio of the components comprising hydrophobic component, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight. In another embodiment the ratio of the components comprising hydrophobic component, the stabilizer and water to the gas propellant is about 100:5 by weight to about 100:25 by weight; or about 100:7 by weight to about 100:20 by weight.
In one or more embodiments there is provided a composition wherein the hydrophobic wax is at a concentration of at least about 30 wt %; 35 wt % 37 wt %; 40 wt %; 45 wt %; 50 wt %; 55 wt %; or 60 wt %.
In one or more embodiments there is provided a composition in which the hydrophobic wax includes at least one liquid wax present at a concentration of at least about 20 wt % and the composition is substantially free of crystals, wherein the at least one liquid wax comprises a fatty alcohol. In some embodiments, the fatty alcohol is at least about 7.5 wt %; 10 wt %; 12 wt %; or 15 wt % of the composition.
In one or more embodiments there is provided a composition in which the hydrophobic wax includes at least one liquid wax present at a concentration of at least about 30 wt % and the composition is substantially free of crystals, wherein the at least one liquid wax comprises a fatty alcohol. In an alternative embodiment the at least one liquid wax comprises a fatty acid. In some embodiments, the fatty alcohol is at least about 7.5 wt %; 10 wt %; 12 wt %; 15 wt %; 20 wt %; or 25 wt % of the composition.
In one or more embodiments there is provided a composition in which the hydrophobic wax includes at least one liquid wax present at a concentration of at least about 35 wt % and the composition is substantially free of crystals, wherein the at least one liquid wax comprises a fatty alcohol. In an alternative embodiment the at least one liquid wax comprises a fatty acid. In some embodiments, the fatty alcohol is at least about 7.5 wt %; 10 wt %; 12 wt %; 15 wt %; 20 wt %; 25 wt %; or 30 wt %. of the composition
In one or more embodiments there is provided a composition in which the hydrophobic wax includes at least one liquid wax present at a concentration of at least about 40% by weight and the composition is substantially free of crystals wherein the at least one liquid wax comprises a fatty alcohol. In an alternative embodiment the at least one liquid wax comprises a fatty acid. In some embodiments, the fatty alcohol is at least about 7.5 wt %; 10 wt %; 12 wt %; 15 wt %; 20 wt %; 25 wt %; 30 wt % or 35 wt % of the composition.
In one or more further embodiments the liquid wax is at least about 45 wt %; and the fatty alcohol comprises at least about 7.5 wt %; 10 wt %; 15 wt %; 20 wt %; 25 wt %; 30 wt %; 35 wt % or 40 wt %; or the liquid wax is at least about 50 wt %; and the fatty alcohol comprises at least about 7.5 wt %; 10 wt %; 15 wt %; 20 wt %; 25 wt %; 30 wt %; 35 wt %; 40 wt %; or 45 wt % or the liquid wax is at least about 55 wt %; and the fatty alcohol comprises at least about 7.5 wt %; 10 wt %; 15 wt %; 20 wt %; 25 wt %; 30 wt %; 35 wt %; 40 wt %; 45 wt %; 50 wt % or the liquid wax comprises at least about 60 wt %; and the fatty alcohol comprises at least about 7.5 wt %; 10 wt %; 12 wt %; 15 wt %; 20 wt %; 25 wt %; 30 wt %; 35 wt %; 40 wt %; 45 wt %; 50 wt %; or 55 wt %.
In one or more embodiments there is provided a composition in which the hydrophobic wax includes at least one liquid wax present at a concentration of at least about 30%, about 35% about 40% or about 45% by weight and the composition is substantially free of crystals and is substantially flowable.
In one or more embodiments there is provided a composition in which the hydrophobic wax present in the composition includes at least one solid wax and at least one liquid wax, wherein the liquid wax is at a concentration of at least about 20 wt %; 25 wt %; 30 wt %; 35 wt % 37 wt %; 40 wt %; 45 wt %; 50 wt %; 55 wt %; or 60 wt % by weight and the composition is substantially free of crystals.
In one or more embodiments there is provided a composition in which the hydrophobic wax present in the composition is at a concentration of at least about 40% by weight and comprises at least one solid wax and the composition is substantially free of crystals.
In one or more embodiments there is provided a composition in which the hydrophobic wax comprises at least one liquid wax and at least one solid wax present at a concentration of at least about 40% by weight and the composition is substantially free of crystals, wherein the liquid wax is a fatty acid.
In one or more embodiments there is provided a composition in which the hydrophobic wax present in the composition comprises at least about 7 wt % of at least one solid wax and at least one liquid wax, and the composition is substantially free of crystals. In some embodiments, the solid wax is at a concentration of at least about 7.5 wt %; 10 wt %; 15 wt %; 20 wt %; 25 wt %; 30 wt %; 35 wt % or 40 wt %. In a further embodiment where the solid wax is at least about 7% or more the liquid wax is at a concentration of at least about 7.5 wt %; 10 wt %; 15 wt %; 20 wt %; 25 wt %; 30 wt %; 35 wt % or 40 wt %.
In one or more embodiments there is provided a composition substantially free of crystals, wherein the hydrophobic wax comprises at least one liquid wax and at least one solid wax present at a concentration of at least about 36% by weight, wherein the amount of solid wax is at least about 8% or wherein the ratio of liquid wax to solid wax is between about 9:2 to about 1:6. For example, in one embodiment, the amount of hydrophobic wax is about 36% and the amount of solid wax is at least about 8% and the amount of liquid wax is about 28%. Similarly, in one embodiment the amount of solid wax is about 10% and the amount of liquid wax is 26%. Likewise, if the amount of hydrophobic wax is about 38% and the amount of solid wax is about at least 8% then the liquid wax is about 30%. Similarly, if the amount of solid wax is about 10% the amount of liquid wax is 28% and so on. More particularly the ratio of liquid wax to solid was is about 9:2; about 4:1; about 3:1; about 2:1; about 1:1; about 1:2; about 1:3; about 1:4 about 1:5 or about 1:6 or anything in between these ratios.
In one or more embodiments the ratio of fatty alcohol to fatty acid is between about 10:9 to about 8:1
In one or more embodiments the ratio of liquid wax to solid wax is between about 10:1 to about 1:10. In one or more other embodiments the ratio of liquid wax to solid wax is between about 5:1 to about 1:5. In one or more further embodiments the ratio of liquid wax to solid wax is between about 1:1 to about 3:1. Alternatively in one or more embodiments the ratio of liquid wax to solid wax is between about 3:1 to about 1:1.
In one or more embodiments there is provided a composition in which the hydrophobic wax includes at least one liquid wax, wherein the liquid wax comprises at least about 10% jojoba oil.
In one or more embodiments there is provided a composition in which the hydrophobic wax comprises at least one liquid wax present at a concentration of at least about 20% by weight, wherein the liquid wax comprises at least about 10% jojoba oil;
In one or more embodiments there is provided a composition in which the hydrophobic wax comprises at least one liquid wax present at a concentration of at least about 30% by weight, wherein the liquid wax comprises at least about 20% jojoba oil.
In one or more embodiments there is provided a composition in which the hydrophobic wax comprises at least about 20% jojoba oil; at least about 30% jojoba oil; at least about 40% jojoba oil; at least about 50% jojoba oil; at least about 60% jojoba oil; or at least about 70% jojoba oil;
In one or more embodiments there is provided a composition in which the hydrophobic wax combination comprises solid wax at a concentration of about 30 wt % or more and the composition is substantially free of crystals.
In one or more embodiments there is provided a composition in which the solid wax is at a concentration of about or less than 37 wt %. In one or more embodiments the compositions described herein further include an active agent.
In an embodiment the active agent is soluble in the composition at an acidic pH. In another embodiment the active agent is non basic or does not cause significant neutralization of the composition. In an embodiment the active agent is solubilized by first dissolving the active agent directly in organic hydrophobic liquid wax or an organic wax or a combination thereof.
In one or more embodiments the compositions described herein include a solvent. Exemplary solvents include, without limitation an organic carrier, a hydrophilic solvent; a hydrophobic solvent; a potent solvent; a polar solvent, a silicone, an emollient, and mixtures thereof.
In one or more embodiments there is provided a composition, wherein the wax, stabilizer and water are selected to generate a surfactant layer or interphase with substantially organized chaos.
In one or more embodiments there is provided a composition, wherein the breakable foam comprises a micro or nano emulsion.
In one or more embodiments there is provided a composition, which is substantially resistant to one or more Freeze-Thaw cycles (FTC).
In one or more embodiments the surface-active agent is a solid, a liquid or a mixture thereof.
Exemplary surface active agents for use in the compositions described herein include a polysorbate, polyoxyethylene (20) sorbitan monostearate, polyoxyethylene (20) sorbitan monooleate, a polyoxyethylene fatty acid ester, Myrj 45, Myrj 49, Myrj 52, Myrj 59, a polyoxyethylene alkynyl ether, polyoxyethylene cetyl ether, polyoxyethylene palmityl ether, polyethylene oxide hexadecyl ether, polyethylene glycol cetyl ether, brij 38, brij 52, brij 56 and brij W1, a sucrose ester, a partial ester of sorbitol, sorbitan monolaurate, sorbitan monolaurate a monoglyceride, a diglyceride, isoceteth-20, a sucrose ester, steareth 2, glyceryl monostearate/PEG 100 stearate, Glyceryl Stearate, Steareth-21, peg 40 stearate, polysorbate 60, polysorbate 80, sorbitan stearate, laureth 4, Sorbitan monooleate, ceteareth 20, steareth 20, ceteth 20, Macrogol Cetostearyl Ether, ceteth 2, PEG-30 Dipolyhydroxystearate, sucrose distearate, polyoxyethylene (100) stearate, PEG 100 stearate, PEG 40 stearate, laureth 4, cetomacrogol ether, Cetearyl alcohol, Cetearyl glucoside, Oleyl alcohol, Steareth-2, Diisopropyl adipate, Capric/caprilic triglicerides, Polysorbate 20; Montanov 68 (CETEARYL ALCOHOL (and) CETEARYL GLUCOSIDE.), Sharonmix 824 (a liquid blend of methyl paraben, ethyl paraben and propyl paraben—in phenoxyethanol), Simusol 165 (Glyceryl stearate and PEG-100 stearate). Methyl glucose sequistearate, Peg 30 dipolyhydroxystearate, sucrose stearic acid esters, sorbitan laureth, sorbitan stearate and mixtures thereof.
In one or more embodiments there is provided a composition, wherein the surface active agent comprises a polysorbate.
In one or more embodiments there is provided a composition, wherein the surface active agent comprises PEG 30 dipolyhydroxysearate.
In one or more embodiments there is provided a composition, wherein the surface active agent also functions as a solvent.
In one or more embodiments there is provided a composition, wherein the polymeric agent is selected from the group consisting of carbopol 934, pemulen TR2, klucel EF, xanthan gum, methocel A4M, and carboxy methyl cellulose or selected from the group consisting of locust bean gum, sodium alginate, sodium caseinate, egg albumin, gelatin agar, carrageenin gum, sodium alginate, xanthan gum, quince seed extract, tragacanth gum, guar gum, cationic guars, hydroxypropyl guar gum, starch, an amine-bearing polymer, chitosan, alginic acid, hyaluronic acid, a chemically modified starch, a carboxyvinyl polymer, polyvinylpyrrolidone, polyvinyl alcohol, a polyacrylic acid polymer, a polymethacrylic acid polymer, polyvinyl acetate, a polyvinyl chloride polymer, a polyvinylidene chloride polymer, methylcellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, hydroxyethyl cellulose, hydroxy propylmethyl cellulose, methylhydroxyethylcellulose, methylhydroxypropylcellulose, hydroxyethylcarboxymethylcellulose, carboxymethyl cellulose, carboxymethylcellulose carboxymethylhydroxyethylcellulose, a cationic cellulose, aluminum starch octenylsuccinate (ASOS), sodium starch octenylsuccinate, PEG 1000, PEG 4000, PEG 6000 and PEG 8000.
In one or more embodiments there is provided a composition, wherein the polymeric agent is a derivatized polymeric emulsifier. In one or other embodiments the polymer is a polymeric surfactant. Non limiting examples are a poloxamer or a pemulen.
The foamable composition can be an emulsion, or microemulsion, including an aqueous phase and an organic carrier phase, which comprises at least one hydrophobic solvent, which is a wax, selected from the group consisting of (1) a fatty alcohol; (2) a fatty acid; and (3) certain naturally occurring waxes. The wax, according to the present invention is hydrophobic. A “hydrophobic solvent” as used herein refers to a material having solubility in distilled water at ambient temperature of less than about 1 gm per 100 mL, in some embodiments less than about 0.5 gm per 100 mL, and in other embodiments less than about 0.1 gm per 100 mL. It is semi-solid or liquid at ambient temperature. The identification of a “hydrophobic solvent”, as used herein, is not intended to characterize the solubilization capabilities of such solvent for any specific active agent or any other component of the foamable composition. Rather, such information is provided to aid in the identification of materials suitable for use as a hydrophobic component in the foamable compositions described herein.
Examples of waxes, suitable as hydrophobic solvents in accordance to the present invention include, but are not limited, to the following:
In one or more embodiments there is provided a composition, wherein the wax is a C8 to C22 fatty acid or fatty alcohol.
In one or more embodiments there is provided a composition, wherein the wax is a C16 to C20 fatty acid or fatty alcohol.
In one or more embodiments there is provided a composition, wherein the wax is a branched chain fatty acid or fatty alcohol.
In one or more embodiments there is provided a composition, wherein the wax is a straight chain fatty acid or fatty alcohol.
In one or more embodiments there is provided a composition, wherein the wax is a saturated fatty acid or fatty alcohol.
In one or more embodiments there is provided a composition, wherein the wax is an unsaturated fatty acid or fatty alcohol.
In one or more embodiments there is provided a composition, wherein the wax is selected from the group consisting of isostearic acid, oleic acid, oleyl alcohol, stearic acid, cetyl alcohol, stearyl alcohol, erucic acid, linoleic acid, arachidonic acid and linolenic acid.
In one or more embodiments there is provided a composition, wherein the wax is selected from the group consisting of: lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, 12-hydroxystearic acid, undecylenic acid, tall acid, isostearic acid, linoleic acid, linolenic acid, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and an equivalent fatty alcohol thereof.
In one or more embodiments there is provided a composition, wherein the wax is selected from the group consisting of animal waxes, spermaceti, lanolin (wool wax), insect waxes, beeswax, chinese wax, vegetable waxes, candelilla wax, castor wax, jojoba oil, rice bran wax; petroleum waxes, paraffin waxes, microcrystalline wax; synthetic waxes, polyethylene waxes, Fischer-Tropsch waxes, chemically modified and substituted waxes; and mineral waxes.
In one or more embodiments there is provided a composition, wherein the wax is selected from the group consisting of coconut oil, palm oil, tallow and jojoba oil.
In one or more embodiments there is provided a composition, wherein the wax is jojoba oil.
In one or more embodiments there is provided a composition further comprising an additional active agent.
In one or more embodiments there is provided a composition, further containing a foam adjuvant. In one or more embodiments certain hydrophobic waxes can function as a foam adjuvant. Solid hydrophobic waxes are preferred. Thus, In addition to the hydrophobic wax acting as the main “oil” phase it can contribute to the foam stability and quality. Mixtures of solid wax with liquid wax can be ideal where for example, depending on the actual ingredients used, a solid wax primarily acts as the adjuvant and a liquid wax as the solvent and co adjuvant.
In one or more embodiments there is provided a composition further containing at least one organic carrier (other than wax) selected from the group consisting of a hydrophobic organic carrier, an emollient and mixtures thereof, at a concentration of about 2% to about 50% by weight.
In one or more embodiments there is provided a composition, wherein the organic carrier is selected from the group consisting of mineral oil, triglycerides, medium chain triglyceride (MCT) oil, capric/caprylic triglyceride, alkyl esters of fatty acids such as isopropyl palmitate, isopropyl myristate, isopropyl isostearate, poly propylene glycol 15-stearly ether, octyl palmitate, cetyl lactate, cetyl ricinoleate, tocopheryl acetate, acetylated lanolin alcohol, cetyl acetate, phenyl trimethicone, glyceryl oleate, tocopheryl linoleate, wheat germ glycerides, arachidyl propionate, myristyl lactate, decyl oleate, ricinoleate, isopropyl lanolate, pentaerythrityl tetrastearate, neopentylglycol dicaprylate/dicaprate, isononyl isononanoate, isotridecyl isononanoate, myristyl myristate, triisocetyl citrate, octyl dodecanol, maleated soybean oil, unsaturated or polyunsaturated oils, such as olive oil, corn oil, soybean oil, canola oil, cottonseed oil, coconut oil, sesame oil, sunflower oil, borage seed oil, syzigium aromaticum oil, hempseed oil, herring oil, cod-liver oil, salmon oil, flaxseed oil, wheat germ oil, evening primrose oils; essential oils; and silicone oils, such as dimethicone, cyclomethicone, polyalkyl siloxane, polyaryl siloxane, polyalkylaryl siloxane, a polyether siloxane copolymer and a poly(dimethylsiloxane)-(diphenyl-siloxane) copolymer and a polypropylene glycol alkyl ether.
In one or more embodiments there is provided a composition further containing at least one polar solvent.
In one or more embodiments there is provided a composition, wherein the polar solvent is selected from the group consisting of dimethyl isosorbide, glycerol, propylene glycol, hexylene glycol, diethylene glycol, propylene glycol n-alkanols, terpenes, di-terpenes, tri-terpenes, limonene, terpene-ol, 1-menthol, dioxolane, ethylene glycol, other glycols, oleyl alcohol, alpha-hydroxy acids, such as lactic acid and glycolic acid, sulfoxides, such as dimethylsulfoxide (DMSO), dimethylformanide, methyl dodecyl sulfoxide, dimethylacetamide, azone (1-dodecylazacycloheptan-2-one), 2-(n-nonyl)-1,3-dioxolane, alkanols, such as dialkylamino acetates, and admixtures thereof.
In one or more embodiments there is provided a composition, wherein the organic carrier is capric/caprylic triglyceride.
In one or more embodiments there is provided a composition, wherein the wax, stabilizer and water are selected to generate an emulsion that can produce a substantially strong and closed packed barrier between the oil and the water phases whilst maintaining a fluid constitution and a surfactant layer or interphase with substantially organized chaos.
In one or more embodiments there is provided a composition, further comprising an additional component selected from the group consisting of a modulating agent, a polar solvent, an anti perspirant, an anti-static agent, a buffering agent, a bulking agent, a chelating agent, a colorant, a conditioner, a deodorant, a diluent, a dye, an emollient, fragrance, a humectant, an occlusive agent, a penetration enhancer, a perfuming agent, a permeation enhancer, a pH-adjusting agent, a preservative, a skin penetration enhancer, a sunscreen, a sun blocking agent, a sunless tanning agent, and a vitamin.
In one or more embodiments there is provided a therapeutic or pharmaceutical composition comprising:

    
    
        i. at least one hydrophobic wax selected from the group consisting of a liquid wax, a solid wax and mixtures thereof;
        ii. at least one stabilizer selected from the group consisting of a surface-active agent, a polymeric agent and mixtures thereof;
        iii. water;
        iv. an active agent; and
        v. a liquefied hydrocarbon gas propellant, wherein the ratio of the solid wax, the liquid wax, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight;
    
    


wherein the vehicle is substantially free from crystals, is substantially flowable and upon release from a pressurized container provides a breakable foam.
The term therapeutic composition includes pharmaceutical composition and both these terms can be used interchangeably.
In an embodiment where the pharmaceutical composition comprises a liquid wax and a solid wax, the stabilizer comprises about 1% to about 5% of at least one surface-active agent and about 1% to about 5% of at least one polymeric agent.
In one or more embodiments there is provided a therapeutic composition, wherein the active agent is selected from the group consisting of active herbal extracts, acaricides, age spot and keratose removing agents, allergen, analgesics, local anesthetics, antiacne agents, antiallergic agents, antiaging agents, antibacterials, antibiotics, antiburn agents, anticancer agents, antidandruff agents, antidepressants, antidermatitis agents, antiedemics, antihistamines, antihelminths, antihyperkeratolyte agents, antiinflammatory agents, antiirritants, antilipemics, antimicrobials, antimycotics, antiproliferative agents, antioxidants, anti-wrinkle agents, antipruritics, antipsoriatic agents, antirosacea agents antiseborrheic agents, antiseptic, antiswelling agents, antiviral agents, antiyeast agents, antiwart agents, astringents, topical cardiovascular agents, chemotherapeutic agents, corticosteroids, dicarboxylic acids, disinfectants, fungicides, hair growth regulators, hormones, hydroxy acids, immunosuppressants, immunoregulating agents, insecticides, insect repellents, keratolytic agents, lactams, metals, metal oxides, mitocides, neuropeptides, steroids, non-steroidal anti-inflammatory agents, oxidizing agents, pediculicides, photodynamic therapy agents, retinoids, sanatives, scabicides, self tanning agents, skin whitening agents, vasoconstrictors, vasodilators, vitamins, vitamin D derivatives, wound healing agents and wart removers as well as agents having activity against superficial basal cell carcinomas, actinic keratoses, Bowen's disease and or other squamous cell carcinomas and molluscum contagiosum.
In one or more embodiments there is provided a therapeutic composition, wherein the wax is present in the composition in an amount sufficient to solubilize the active agent.
In one or more embodiments there is provided a therapeutic composition, wherein the active agent is selected from the group consisting of at least one of imiquimod, resiquimod, gardiquimod, an interferon, an immunomodulator, podophyllin (anti-mitotic), podofilox, 5-fluorouracil (5-FU), and trichloroacetic acid (TCA), fluorouracil, afovirsen, inosine pranobex, podophyllum, trichloroacetic acid, thiotep, diclofenac, 5-aminolevulinic acid and derivatives, tretinoin, a cyclic peptide, cyclosporine, tacrolimus, tresperimus, pimecrolimus, sirolimus, verolimus, laflunimus and laquinimod.
In one or more embodiments there is provided a therapeutic composition, wherein the active agent is imiquimod.
In one or more embodiments there is provided a therapeutic composition, wherein the active agent is used against herpes simplex virus infections, other viral infections and eczema and as a vaccine adjuvant.
In one or more embodiments there is provided a therapeutic composition, wherein imiquimod is used in combination with at least one of the group consisting of meglumine antimoniate; cryotherapy; acyclovir; 5-aminolevulinic acid; fluorouracil; salicylic acid a COX inhibitor and sulindac.
In one or more embodiments there is provided a therapeutic composition, wherein the active agent is a steroid.
In one or more embodiments there is provided a therapeutic composition, wherein the steroid is selected from the group consisting of hydrocortisone, hydroxyltriamcinolone, alpha-methyl dexamethasone, dexamethasone-phosphate, beclomethsone dipropionate, clobetasol valemate, desonide, desoxymethasone, desoxycorticosterone acetate, dexamethasone, dichlorisone, diflorasone diacetate, diflucortolone valerate, fluadrenolone, fluclorolone acetonide, fludrocortisone, flumethasone pivalate, fluosinolone acetonide, fluocinonide, flucortine butylester, fluocortolone, fluprednidene (fluprednylidene) acetate, flurandrenolone, halcinonide, hydrocortisone acetate, hydrocortisone butyrate, methylprednisolone, triamcinolone acetonide, cortisone, cortodoxone, flucetonide, fludrocortisone, difluorosone diacetate, fluradrenolone acetonide, medrysone, amcinafel, amcinafide, betamethasone and the balance of its esters, chloroprednisone, chlorprednisone acetate, clocortelone, clescinolone, dichlorisone, difluprednate, flucloronide, flunisolide, fluoromethalone, fluperolone, fluprednisolone, hydrocortisone valerate, hydrocortisone cyclopentylpropionate, hydrocortmate, mepreddisone, paramethasone, prednisolone, prednisone, beclomethasone dipropionate, and triamcinolone.
In one or more embodiments there is provided a therapeutic composition, wherein the active agent is an immunomodulator.
In one or more embodiments there is provided a therapeutic composition, wherein the immunomodulator is selected from the group consisting of a cyclic peptide, cyclosporine, tacrolimus, tresperimus, pimecrolimus, sirolimus, verolimus, laflunimus, laquinimod and imiquimod.
In one or more embodiments there is provided a therapeutic composition, wherein the wax is present in the composition in an amount sufficient to solubilize the immunomodulator.
In one or more embodiments there is provided a therapeutic composition, wherein the composition further comprises a solvent selected from the group consisting of an organic carrier, a hydrophilic solvent; a hydrophobic solvent; a potent solvent; a polar solvent, a silicone, an emollient, and mixtures thereof.
In one or more embodiments there is provided a therapeutic composition, wherein the wax, stabilizer and water are selected to generate an emulsion that is substantially resistant to phase reversal.
In one or more embodiments there is provided a therapeutic composition, wherein the wax, stabilizer and water are selected to generate a surfactant layer or interphase with substantially organized chaos.
In one or more embodiments there is provided a method of treating, ameliorating or preventing a disorder of a mammalian subject, comprising: administering a foamable therapeutic composition to a target site, the composition comprising:

    a. a therapeutically effective amount of an active agent;
    b. at least one hydrophobic wax selected from the group consisting of a liquid wax, a solid wax and mixtures thereof;
    c. at least one stabilizer selected from the group consisting of a surface-active agent, a polymeric agent and mixtures thereof; and
    d. water;
    e. a liquefied hydrocarbon gas propellant, wherein the ratio of the solid wax, the liquid wax, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight;

wherein the vehicle is substantially free from crystals, is substantially flowable and upon release from a pressurized container provides a breakable foam.



In one or more embodiments there is provided a method of treating, wherein the composition is contained in a pressurized container and further comprises a liquefied hydrocarbon gas propellant at a concentration of about 3% to about 35% by weight of the total composition, is substantially flowable and provides a foam upon release and wherein the wax, stabilizer and water are selected to generate a breakable foam of good to excellent quality.
In one or more embodiments there is provided a method of treating, wherein the target site is selected from the group consisting of the skin, a body cavity, a mucosal surface, the nose, the mouth, the ear canal, the vagina and the rectum.
In one or more embodiments there is provided a method of treating, wherein the disorder is selected from the group consisting of dermatological pain, dermatological inflammation, acne, acne vulgaris, inflammatory acne, non-inflammatory acne, acne fulminans, nodular papulopustular acne, acne conglobata, dermatitis, bacterial skin infections, fungal skin infections, viral skin infections, parasitic skin infections, skin neoplasia, skin neoplasms, pruritis, cellulitis, acute lymphangitis, lymphadenitis, erysipelas, cutaneous abscesses, necrotizing subcutaneous infections, scalded skin syndrome, folliculitis, furuncles, hidradenitis suppurativa, carbuncles, paronychial infections, rashes, erythrasma, impetigo, eethyma, yeast skin infections, warts, molluscum contagiosum, trauma or injury to the skin, post-operative or post-surgical skin conditions, scabies, pediculosis, creeping eruption, eczemas, psoriasis, pityriasis rosea, lichen planus, pityriasis rubra pilaris, edematous, erythema multiforme, erythema nodosum, granuloma annulare, epidermal necrolysis, sunburn, photosensitivity, pemphigus, bullous pemphigoid, dermatitis herpetiformis, keratosis pilaris, callouses, corns, ichthyosis, skin ulcers, ischemic necrosis, miliaria, hyperhidrosis, moles, Kaposi's sarcoma, melanoma, malignant melanoma, basal cell carcinoma, squamous cell carcinoma, poison ivy, poison oak, contact dermatitis, atopic dermatitis, rosacea, purpura, moniliasis, candidiasis, baldness, alopecia, Behcet's syndrome, cholesteatoma, Dercum disease, ectodermal dysplasia, gustatory sweating, nail patella syndrome, lupus, hives, hair loss, Hailey-Hailey disease, chemical or thermal skin burns, scleroderma, aging skin, wrinkles, sun spots, necrotizing fasciitis, necrotizing myositis, gangrene, scarring, and vitiligo; and wherein the active agent is suitable for treating said disorderm or is selected from the group consisting of chlamydia infection, gonorrhea infection, hepatitis B, herpes, HIV/AIDS, human papillomavirus (HPV), genital warts, bacterial vaginosis, candidiasis, chancroid, granuloma Inguinale, lymphogranuloma venereum, mucopurulent cervicitis (MPC), molluscum contagiosum, nongonococcal urethritis (NGU), trichomoniasis, vulvar disorders, vulvodynia, vulvar pain, yeast infection, vulvar dystrophy, vulvar intraepithelial neoplasia (VIN), contact dermatitis, pelvic inflammation, endometritis, salpingitis, oophoritis, genital cancer, cancer of the cervix, cancer of the vulva, cancer of the vagina, vaginal dryness, dyspareunia, anal and rectal disease, anal abscess/fistula, anal cancer, anal fissure, anal warts, Crohn's disease, hemorrhoids, anal itch, pruritus ani, fecal incontinence, constipation, polyps of the colon and rectum; warts; herpes simplex virus infections, other viral infections, superficial basal cell carcinomas, actinic keratoses, Bowen's disease and/or other squamous cell carcinomas, molluscum contagiosum and eczema, and wherein the active agent is suitable for treating said disorder.
In one or more embodiments there is provided a method of treating, wherein the disorder is a dermatological disorder, which can be treated, ameliorated or prevented by a topical steroid, an immunomodulator or an anti-infective agent.
In one or more embodiments there is provided a method of treating, wherein the active agent is selected from the group consisting of imiquimod, resiquimod, gardiquimod, an interferon, an immunomodulator, podophyllin (anti-mitotic), podofilox, 5-fluorouracil (5-FU), and trichloroacetic acid (TCA), fluorouracil, afovirsen, inosine pranobex, podophyllum, trichloroacetic acid, thiotep, diclofenac, 5-aminolevulinic acid and derivatives, tretinoin, a cyclic peptide, cyclosporine, tacrolimus, tresperimus, pimecrolimus, sirolimus, verolimus, laflunimus and laquinimod.
In one or more embodiments there is provided a pharmaceutical composition, further comprising an additional component selected from the group consisting of a modulating agent, a polar solvent, an anti perspirant, an anti-static agent, a buffering agent, a bulking agent, a chelating agent, a colorant, a conditioner, a deodorant, a diluent, a dye, an emollient, fragrance, a humectant, a moisturizer, an occlusive agent, a penetration enhancer, a perfuming agent, a permeation enhancer, a pH-adjusting agent, a preservative, a skin penetration enhancer, a sunscreen, a sun blocking agent, a sunless tanning agent,
In one or more embodiments there is provided a pharmaceutical composition comprising:

    
    
        i. a liquid wax selected from the group consisting of isostearic acid, oleyl alcohol, octyldodecanol, isostearyl alcohol and jojoba oil;
        ii. a stabilizer comprising about 1% to about 5% of at least one surface-active agent comprising a liquid surfactant and about 0.1% to about 5% of at least one polymeric agent;
        iii. water; and
        iv. an active agent,

wherein the composition is substantially free from crystals, is substantially flowable and upon release from a pressurized container provides a breakable foam;

wherein the liquid wax is about 7% to about 70% by weight of the composition.

    
    


In one or more embodiments there is provided a pharmaceutical composition comprising:

    
    
        i. a liquid wax selected from the group consisting of isostearic acid, oleyl alcohol, octyldodecanol, isostearyl alcohol, and jojoba oil and a solid wax selected from the group consisting of stearic acid, cetyl alcohol and stearyl alcohol;
        ii. a stabilizer comprising about 1% to about 5% of at least one surface-active agent comprising a liquid surfactant and about 0.1% to about 5% of at least one polymeric agent;
        iii. water; and
        iv. an active agent,

wherein the vehicle is substantially free from crystals, is substantially flowable and upon release from a pressurized container provides a breakable foam.

    
    


In one or more embodiments the ranges of an ingredient can be between any two figures mentioned for that ingredient.
In one or more embodiments the ranges of a ratio between two substances A:B can be between any two sets of figures mentioned for that ratio.
In one or more embodiments there is provided a vehicle or a therapeutic or a pharmaceutical composition in a non foam state.
In one or more embodiments there is also provided a formulation of any of the compositions described herein for use in the manufacture of a medicament.
In one aspect, a method of treating, ameliorating or preventing a disorder of a mammalian subject is provided. The method includes administering any of the compositions described herein to a target site.
All % values are provided on a weight (w/w) basis.
Wax
In an embodiment, the organic carrier comprises a wax. By wax is meant in the wider sense, waxes, waxy substances, counterparts and derivatives thereof. Waxes may be natural such as beeswax, carnauba and paraffin or artificial. Some artificial materials that exhibit similar properties are also described as wax or waxy. Chemically, a wax may be an ester of ethylene glycol (ethan-1,2-diol) and two fatty acids, as opposed to a fat which is an ester of glycerin (propan-1,2,3-triol) and three fatty acids. It may also be a combination of other fatty alcohols with fatty acids. Non limiting examples of: animal waxes are spermaceti and lanolin (wool wax); insect waxes are beeswax and chinese wax; vegetable waxes are candelilla wax, castor wax, jojoba oil and rice bran wax; petroleum waxes are paraffin waxes and microcrystalline wax; synthetic waxes are polyethylene waxes Fischer-Tropsch waxes, chemically modified and substituted waxes; and mineral waxes. Formerly waxes were fatty acid esters with monohydric fatty alcohols having wax like properties, however, the category has been widely extended to include any organic material having wax-like properties. Some typical characteristics of waxes are water repellency being hydrophobic, relatively low viscosity when liquid, and plasticity. In the context herein, a wax can be a solid wax or a liquid wax and includes waxy substances, like fatty acids and their fatty alcohol counterparts, which can be short, medium and long chain. The fatty acid or alcohol backbone may be straight, branched, saturated, unsaturated, or hydrogenated, unhydrogenated, natural, or synthetic. Where one type of backbone produces a waxy substance then molecules with the substantially the same backbone are also deemed as being part of the wax family or being a waxy substance counterpart or derivative thereof. For example, stearic acid and stearyl alcohol are waxy solids with a C18 backbone. In other cases, however, where the carbon backbone chain is also C18, such as isostearic acid, oleic acid and oleyl alcohol, they are liquids but are likewise considered to be waxy substances, having a commonality with regards to the number of carbon atoms in the formula. Also considered within the scope is where hydrogenation would form a wax or waxy substance. The significance of this difference in liquidity of molecules having the same or similar backbone chain on foamable compositions is investigated herein. Other non limiting examples of fatty acids and fatty alcohols having a commonality of formula of backbone C chain are shown in Table 1:















TABLE 1





Saturated
Solid = S
C Formula
Unsaturated
Solid = S
C Formula
Fatty
Solid = S
C Formula


Acid
Liquid = L
Backbone
Acid
Liquid = L
Backbone
Alcohol
Liquid = L
Backbone







Butyric
L
C4:0*








Caproic
L
C6:0


Caprylic
L
C8:0



capryl
L
C8:0


Capric
S
C10:0



1-nonanol
L
C9:0








Capric
L
C10:0








(strong








skin








irritant can








be








harmful)








undecanol
L
C11:0


Lauric
S
C12:0



1
S
C12:0








dodecanol


Myristic
S
C14:0
Myristoleic
S
C14:1
myristyl
S
C14:0





acid:


Palmitic
S
C16:0



cetyl
S
C16:0





Palmitoleic
L
C16:1
palmitoleyl

C16:1





acid:


Stearic
S
C18:0
Oleic acid:
L
C18:1
stearyl
S
C18:0


Isostearic
L
C18:B



isostearyl
L
C18:B








oleyl
L
C18:1





Linoleic
L
C18:2





acid:





Alpha-
L
C18:3





linolenic





acid:


Arachidic
S
C20:0
Arachidonic
L
C20:4
arachidyl
S
C20:0





acid


Behenic
S
C22:0
Eicosapentaenoic
S
C20:5
behenyl
S
C22:0





acid





Erucic acid:
S
C22:1





Docosahexaenoic
S
C22:6





acid





*The carbon backbone formula is interpreted as follows: the first number is the number of carbons in the backbone, while the second number is the degree of unsaturation (i.e., number of double bonds). Accordingly, C18:0 refers to a 18-carbon straight chain, while C18:1 refers to 18-carbon straight chain with one double bond and C18:2 refers to 18-carbon straight chain with two double bonds. “B” refers to a branched chain (i.e., C18:B refers to 18-carbon branced chain).






As will be appreciated only those fatty acids and fatty alcohols that are suitable for application to the skin, eyes or body cavity may be used in a pharmaceutical or cosmetic formulation. Capric alcohol for example is known to cause high irritability to skin and eyes and if splashed into the eyes it can cause permanent damage and its use can be harmful. Accordingly, it is excluded from the scope herein.
In selecting a wax in order to make a foamable formulation careful thought must be given not only to whether it is liquid or solid, but also to its length, its shape and its usability in a therapeutic composition. Usability should be looked at both from the aspect of the suitability for the target to which the formulation is to be applied and also from the aspect of whether it can act as a destabiliser or defoamer in the proposed formulation.
In an embodiment, one or both of the fatty alcohol and fatty acid are a straight-chain molecules. In another embodiment one or both are branched. In a further embodiment one or both are saturated and in another embodiment one or both are unsaturated. When unsaturated one or both may be cis or trans unsaturated. Further one or both may be polyunsaturated. In an additional embodiment one or both are hydrogenated and in a different embodiment one or both are unhydrogenated. In an embodiment mixtures of two or more types may be combined.
Additional members are derived from natural products or from synthesis.
As can been seen from Table 1, long, straight chain saturated fatty acids (C10:0 and higher) are solid at room temperature, which does not make them suitable as solvents and makes them difficult to use in higher concentrations for foamable formulations and foam despite their useful properties. The unsaturated long chain fatty acids like e.g. oleic acid are liquid at room temperature, so they are potentially suitable as solvents and easier to use at higher concentrations, but are potentially unstable because of the existence of double bond(s). Branched fatty acids mimic the properties of the straight chain unsaturated fatty acids in many respects. However, they do not have the disadvantage of being unstable. For example branched C18:0 fatty acid (commercially known as isostearic acid) is liquid at room temperature, but is not as unstable as its C18:1 unsaturated counterpart, since unsaturated bonds are absent in branched C18:0. Therefore, branched fatty acids are for many applications more desirable than straight chain fatty acids. (The term “branched fatty acids” is herein to be understood to comprise fatty acids which contain one or more alkyl side groups, which can be attached to the carbon chain at any position. Such alkyl groups are generally short (e.g., having 1-6 carbon atoms, 1-5 carbon atoms, 1-4 carbon atoms, or 1-3 carbon atoms). Branched fatty acids (and similarly branched fatty alcohols) due to their irregular shape can be more chaotic than their straight chain counterparts as is explained in more detail below.
In one or more embodiments the wax, waxy substance, counterpart or derivative thereof is a saturated branched fatty acid or fatty alcohol.
In one embodiment fatty acids which may be used in the fatty acid waxy substances, counterparts or derivatives include those having an alkyl or alkenyl group having 12 or more carbon atoms, in some embodiments 14 to 22 carbon atoms, and in other embodiments 16-22 carbon atoms. Examples of such fatty acid waxes are fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, 12-hydroxystearic acid, undecylenic acid, tall acid, isostearic acid, linoleic acid, linolenic acid, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), or the equivalent fatty alcohols.
In another embodiment composite fatty acids such as from coconut oil, palm oil, tallow and jojoba oil may be used.
In one or more embodiments, the waxes can be solid substances and in one or more embodiments they may be liquid. In other embodiments a combination of liquid and solid molecules is used.
In an embodiment a saturated fatty acid such as isostearic acid or stearic acid, is preferable due to the stability and the easy overlapping application. These fatty acids may be used alone or in any mixture thereof. For example, for higher concentrations isostearic acid can be used alone or in combination with stearic acid. Indeed, skin feeling can be improved when two or more fatty acids such as stearic acid and isostearic acid are used in combination. The same reasoning is applicable with appropriate changes to fatty alcohols.
In one or more embodiments, the waxes can act as a solvent.
In one or more embodiments, the waxes can act as an emollient.
In one or more embodiments, the waxes can act as a penetration enhancer.
In one or more embodiments, where they are branched or unsaturated they can provide some substantially organized chaos by virtue of their non linear shape enabling both shakability and flowability of the wax formulation and potentially enhanced skin penetration.
Nature moves or tends towards chaos although passing through certain stable states on the way. In a foamable formulation comprising an oil phase and a water phase it is desirable to form a stable emulsion by use of surfactants. Where the surfactant comprises for example, fatty acid or alcohol chains it can form a reasonably tightly packed layer where the said fatty acid or alcohol chains are straight chain and saturated. Relatively speaking such a layer can be considered organised. If unsaturated chains or branched are introduced or used then the molecules are not straight and the backbone can have a mild “v” shape like in oleic acid or in erucic acid or a more pronounced “v” as in linoleic acid or a “u” shape as in arachidonic acid or a half “w” shape as in linolenic acid or a “t” shape in isostearic acid. Without being bound by any theory by using such non linear molecules in forming a foamable composition the surfactant layer or interphase is likely to be less packed and more disrupted making the surfactant layer or interphase in very general terms more fluid and fluidizing, which in turn may improve the flowability of the formulation and or also skin or mucosal membrane penetration. The presence of fatty acids or fatty alcohols in the formulation can interfere with the packing of the surfactant layer or interphase and depending on the surfactants and fatty acids and or alcohols used can improve or disrupt the packing and intern the oil/water interphase. By substantially organized with reference to a surfactant layer of an oil and water or wax and water emulsion is meant a relatively organised well packed layer holding the oil and water or wax and water phases together. By substantially organized chaos it is meant to refer to and to describe a surfactant layer or interphase where comparatively it is to some extent being disrupted and tending towards some chaos or increased liquidity and fluidization or being less tightly packed, due to the selected use of such non linear molecules in the composition. The effect of this substantially organised chaos may vary from formulation to formulation and may be influenced by surface and interfacial tensions. In other words whilst there is an overall structuring effect in the formulation due to the stabiliser and or the fatty acids and or fatty alcohols the effect can be modulated or partially or temporarily disrupted by introducing a non linear molecule which facilitates for example liquidity, fluidization and or penetration. In addition this phenomenon can have an effect on the solubility of certain active agents both in the formulation and or in the interphase.
In one or more embodiments, certain waxes can act as a foam adjuvant.
In one or more embodiments, the fatty alcohol is oleyl alcohol.
Oleyl alcohol occurs as a pale yellow oily liquid and is sometimes used as an antifoaming agent; solubilizing agent/dissolution enhancer; emollient; emulsifying agent; skin penetrant; and sustained-release agent. Oleyl alcohol is mainly used in topical pharmaceutical formulations and has been used in transdermal delivery formulations. It has been utilized in aerosol formulations of insulin and albuterol. Therapeutically, it has been suggested that oleyl alcohol may exhibit antitumor properties via transmembrane permeation. Oleyl alcohol is soluble in ethanol (95%), and ether but practically insoluble in water and should be stored in a well-closed container in a cool, dry, place. Oleyl alcohol is mainly used in topical pharmaceutical formulations and is generally regarded as a nontoxic and nonirritant material at the levels employed as an excipient although contact dermatitis due to oleyl alcohol has been reported. Oleyl alcohol and propylene glycol are miscible although they are hydrophobic and hydrophilic and therefore it is predicted that it should be possible to make waterless waxy or waxy substances foamable compositions and foam. To the extent that isostearic acid and propylene glycol or stearic acid and propylene glycol are likewise miscible the same will apply to them.
In one or more embodiments, the fatty acid is isostearic acid.
Isostearic acid is a naturally occurring fatty acid, primarily comprising methyl branched isomers of octadecanoic acid. It main uses in the cosmetic and pharmaceutical industries are as a binding agent as an emulsifier/surfactant and as a lubricant It is a nearly water-white liquid with a very low odor. Isostearic acid is an emollient that can form a lipid film on the skin that is permeable to water vapor, oxygen, and carbon dioxide. Isostearic acid is recommended for use in moisturizing cosmetics and is similar to waxes secreted by birds for feather maintenance. Isostearic acid, provides a combination of the properties (from the C18 chain length) including retaining the stability of stearic acid the with the liquidity, solubility and physical properties conferred by oleic acid but without the disadvantage of the unsaturation.
In one or more embodiments, the fatty acid is oleic acid.
Oleic acid is a yellowish to pale brown, oily liquid that has been used as an emulsifying agent in topical pharmaceutical formulations. It has also been used as a penetration enhancer in transdermal formulations. It is miscible with ethanol (95%), ether, hexane, and fixed and volatile oils; but practically insoluble in water. On exposure to air, oleic acid gradually absorbs oxygen and darkens in color. At atmospheric pressure, it decomposes when heated at 80-100° C. Oleic acid should be stored in a well-filled, well-closed container, protected from light, in a cool, dry place. Oleic acid is incompatible with aluminum, calcium, heavy metals, iodine solutions, perchloric acid, and oxidizing agents and also reacts with alkalis to form soaps.
In one or more embodiments, the fatty acid is stearic acid.
Stearic acid (octadecanoic acid) is a straight chain fatty acid and may contain palmitic acid. Stearic acid is widely used in oral and topical pharmaceutical formulations and in cosmetics It has been used as an emulsifying agent and solubilizing agent; as a foam adjuvant, a lubricant, and binder. Stearic acid has also been suggested as a sustained-release drug carrier. When partially neutralized with alkalis or triethanolamine, stearic acid is used in the preparation of creams. It is soluble in ethanol (95%), hexane, and propylene glycol but is practically insoluble in water. Stearic acid is incompatible with most metal hydroxides and may be incompatible with oxidizing agents. Studies have suggested possible drug incompatibilities, e.g. with naproxen. Nevertheless, it is generally regarded as a nontoxic and nonirritant material, although it is combustible.
In one or more embodiments, isostearic acid and stearic acid are used in combination.
In one or more embodiments, oleyl alcohol and stearic acid are used in combination.
In one or more embodiments, oleyl alcohol and stearic acid are used in combination.
In one or more embodiments, at least any two from the group consisting of caprilic acid, capryl alcohol, capric acid, capric alcohol, palmitic acid, cetyl alcohol, stearic acid, isostearic acid, stearyl alcohol, and oleyl alcohol are used in combination.
In one or more embodiments, a fatty alcohol is used in combination with a fatty acid. In an embodiment the amount of fatty alcohol is in excess of the amount of fatty acid. In an embodiment the ratio of fatty alcohol to fatty acid is about 10:9, about 5:4, about 4:3, about 3:2, about 2:1, about 3:1, about 4:1, about 5:1, about 8:1, about 10:1, about 20:1, about 40:1, about 80:1, or is any ratio between these ratios.
In one or more embodiments, a liquid wax is used in combination with a solid wax. In an embodiment the amount of liquid wax is in excess of the amount of solid wax. In an embodiment the ratio of liquid wax to solid wax is about 5:4, about 4:3, about 3:2, about 2:1, about 3:1, about 4:1, about 5:1, about 10:1, about 20:1, about 40:1, about 80:1, or is any ratio between these ratios. In another embodiment the amount of solid wax is in excess of the amount of liquid wax. In an embodiment the ratio of solid wax to liquid wax is about 5:4, about 4:3, about 3:2, about 2:1, about 3:1, about 4:1, about 5:1, about 6:1, about 7:1, about 8:1, about 10:1, or is any ratio between these ratios.
In one or more embodiments, the fatty acid and the fatty alcohol can be linked by a linker. A natural example is found in jojoba oil.
Jojoba oil (pronounced “ho-HO-bah”) is the liquid wax produced in the seed of the Jojoba (Simmondsia chinensis) plant. Jojoba oil is a straight chain wax ester, 36 to 46 carbon atoms in length. Each molecule consists of a fatty acid and a fatty alcohol joined by an ester bond. Each molecule has two points of cis-unsaturation, both located at the 9th carbon atom from either end of the molecule. Jojoba oil comprises approximately 66-71% eicosenoic acid, 14-20% docosenoic acid and 10-13% oleic acid. Refined jojoba oil is colorless and odorless. The melting point of jojoba oil is approximately 10° C. Jojoba oil is relatively shelf-stable when compared with other vegetable oils. Unlike common vegetable oils, jojoba oil is chemically very similar to human sebum. Most jojoba oil is used as an ingredient in cosmetics and personal care products, especially skin care and hair care. Therapeutically it can aid in the healing process.
Sebum acts to protect and waterproof hair and skin, and keep them from becoming dry, brittle and cracked. It can also inhibit the growth of microorganisms on skin. It is thought that likewise, formulations with substances such as waxes that can mimic sebum for example like jojoba oil, stearic acid, isostearic acid, oleyl alcohol and the like including combinations thereof and especially in higher concentrations can provide protection to the hair and skin.
In one embodiment a foamable composition as described herein includes (a) at least about 10% by weight jojoba oil; (b) a stabilizer component comprising a surface-active agent, a polymeric agent or a mixture thereof; (c) water; and (d) a liquefied hydrocarbon gas propellant.
In one embodiment a foamable composition as described herein includes (a) at least about 10% by weight jojoba oil; (b) a stabilizer component comprising a surface-active agent, a polymeric agent or a mixture thereof; (c) water; and (d) a liquefied hydrocarbon gas propellant, in which the ratio of the component, the stabilizer and water to the gas propellant is about 100:3 by weight to about 100:35 by weight;
wherein the composition is substantially free from crystals and is substantially flowable; and
in which, when the stabilizer component comprises a polymeric agent, the polymeric agent is present in the vehicle composition at a concentration of about 0.01% to about 5% by weight and includes a bioadhesive agent, a gelling agent, a film forming agent and a phase change agent; and

wherein, upon release from a pressurized container, the foam produced is breakable.

In another embodiment the jojoba foamable composition further includes a solid wax. In an alternative embodiment the jojoba foamable composition includes another liquid wax. In a further embodiment the jojoba foamable composition includes another liquid wax and a solid wax
In further embodiment the jojoba composition includes a liquid wax, wherein the concentration of the liquid wax and the jojoba oil together in the composition is at least about 20% by weight. In one or more further embodiments the concentration is at least about 25% by weight; 30% by weight; 35% by weight; or 40% by weight.
In a still further embodiment the jojoba composition comprises a liquid wax and a solid wax wherein the concentration of the liquid wax, the solid wax and the jojoba oil together in the composition is at least about 20% by weight. In one or more further embodiments the concentration is at least about 25% by weight; 30% by weight; 35% by weight; or 40% by weight.
In one or more embodiments, the fatty acid or alcohol is a biologically active. For example, benhenyl alcohol has some antiviral properties. In an embodiment, biologically active fatty acid or alcohol possesses keratolytic activities.
In an embodiment, the waxy substance is incorporated in the foamable composition in a safe and effective amount. The term “safe and effective” means an amount of an active agent that exerts a therapeutic effect on a specific disorder, without causing adverse effects that may prohibit the use of said active agent in the treatment of said disorder.
Although the presence of fatty acids and or fatty alcohol in the formulations may be high the formulations are substantially non irritating for one or more of the following reasons. By providing and applying the wax formulations in a low density foam preparation only relatively small amounts may be needed to cover a target surface when compared to a cream. Low levels of surfactants preferably non ionic are used. Non or low irritant waxes are selected that are safe and effective. By providing formulations in which the waxes and any active ingredients are dissolved the formulations are substantially free from crystals or particles which can irritate the skin.
In one or more embodiments, the wax, waxy substance, counterpart or derivative thereof contributes to the foam structure.
In one or more embodiments, the fatty acid is present in the composition in an ionized state.
In one or more embodiments, the ratio of wax to water is about 1:50; about 1:25, about 1:10; about 1:9; about 1:5; about 1:3; about 2:5; about 1:2; about; 3:5; about 2:3; about 1:1; about 3:2; about 5:3 about 2:1 about 3:1; about 4:1; about 5:1; about 9:1; or about 10:1.
The sensory properties of foams containing a waxy substance are favorable.
Foam Adjuvant
Optionally, the foamable vehicle further includes a foam adjuvant selected from the group consisting of a fatty alcohol having 15 or more carbons in their carbon chain; a fatty acid having 16 or more carbons in their carbon chain; fatty alcohols, derived from beeswax and including a mixture of alcohols, a majority of which has at least 20 carbon atoms in their carbon chain; a fatty alcohol having at least one double bond; a fatty acid having at least one double bond; a branched fatty alcohol; a branched fatty acid and a fatty acid substituted with a hydroxyl group and mixtures thereof and wherein the foam adjuvant is solid or waxy at room temperature or if a mixture at least one of the mixture is solid or waxy at room temperature.
In one or more embodiments the foam adjuvant is a wax, waxy substance, counterparts or derivative thereof.
Additional Organic Carrier
Optionally, the foamable vehicle further includes at least one additional organic carrier selected from the group consisting of a hydrophobic organic carrier, an emollient and mixtures thereof, at a concentration of about 2% to about 50% by weight. The hydrophobic solvent and/or the emollient can be selected from the group consisting of mineral oil, triglycerides, capric/caprylic triglyceride, alkyl esters of fatty acids such as isopropyl palmitate, isopropyl isostearate, octyl palmitate, cetyl lactate, cetyl ricinoleate, tocopheryl acetate, acetylated lanolin alcohol, cetyl acetate, phenyl trimethicone, glyceryl oleate, tocopheryl linoleate, wheat germ glycerides, arachidyl propionate, myristyl lactate, decyl oleate, ricinoleate, isopropyl lanolate, pentaerythrityl tetrastearate, neopentylglycol dicaprylate/dicaprate, isononyl isononanoate, isotridecyl isononanoate, myristyl myristate, triisocetyl citrate, octyl dodecanol, maleated soybean oil, unsaturated or polyunsaturated oils, such as olive oil, corn oil, soybean oil, canola oil, cottonseed oil, coconut oil, sesame oil, sunflower oil, borage seed oil, syzigium aromaticum oil, hempseed oil, herring oil, cod-liver oil, salmon oil, flaxseed oil, wheat germ oil, evening primrose oils; essential oils; and silicone oils, such as dimethicone, cyclomethicone, polyalkyl siloxane, polyaryl siloxane, polyalkylaryl siloxane, a polyether siloxane copolymer and a poly(dimethylsiloxane)-(diphenyl-siloxane) copolymer.
In an embodiment, the organic carrier is a polypropylene glycol alkyl ether (PPG alkyl ether). PPG alkyl ethers are liquid, water-insoluble propoxylated fatty alcohols, having the molecular formula of RO(CH2CHOCH3)n; wherein “R” is a straight-chained or branched C4 to C22 alkyl group; and “n” is in the range between 4 and about 50. They are organic liquids that function as skin-conditioning agent in pharmaceutical and cosmetic formulations. Non-limiting exemplary PPG alkyl ethers include PPG stearyl ethers and PPG Butyl Ether. Preferred PPG alky ethers according to the present invention include PPG-15 Stearyl Ether, PPG-2 Butyl Ether, PPG-9-13 Butyl Ether and PPG-40 Butyl Ether.
In an embodiment, the organic carrier is a paraffin, glycerin or a petrolatum, which is also termed “white petrolatum” and “Vaseline”. Preferably, one or more of paraffin, glycerin or petroleum used at between about 1% to about 5%.
Polymeric Agent
In some embodiments, the composition contains a polymeric agent selected from the group consisting of a bioadhesive agent, a gelling agent, a film forming agent and a phase change agent. A polymeric agent enhances the creation of foam having fine bubble structure, which does not readily collapse upon release from the pressurized aerosol can. The polymeric agent serves to stabilize the foam composition and to control drug residence in the target organ.
Exemplary polymeric agents include, in a non-limiting manner, naturally-occurring polymeric materials, such as locust bean gum, sodium alginate, sodium caseinate, egg albumin, gelatin agar, carrageenin gum, sodium alginate, xanthan gum, quince seed extract, tragacanth gum, guar gum, cationic guars, hydroxypropyl guar gum, starch, amine-bearing polymers such as chitosan; acidic polymers obtainable from natural sources, such as alginic acid and hyaluronic acid; chemically modified starches and the like, carboxyvinyl polymers, polyvinylpyrrolidone, polyvinyl alcohol, polyacrylic acid polymers, polymethacrylic acid polymers, polyvinyl acetate polymers, polyvinyl chloride polymers, polyvinylidene chloride polymers and the like.
Additional exemplary polymeric agents include semi-synthetic polymeric materials such as cellulose ethers, such as methylcellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, hydroxyethyl cellulose, hydroxy propylmethyl cellulose, methylhydroxyethylcellulose, methylhydroxypropylcellulose, hydroxyethylcarboxymethylcellulose, carboxymethyl cellulose, carboxymethylcellulose carboxymethylhydroxyethylcellulose, and cationic celluloses, carbomer (homopolymer of acrylic acid is crosslinked with an allyl ether pentaerythritol, an allyl ether of sucrose, or an allyl ether of propylene, such as Carbopol® 934, Carbopol® 940, Carbopol® 941, Carbopol® 980 and Carbopol® 981, pemulen, klucel, and aluminum starch octenylsuccinate (ASOS) or other derivatized polymers. Polyethylene glycol, having molecular weight of 1000 or more (e.g., PEG 1,000, PEG 4,000, PEG 6,000 and PEG 10,000) also have gelling capacity and while they are considered herein as “secondary polar solvents”, as detailed herein, they are also considered polymeric agents.
In one or more embodiments the polymeric agents have emulsifying properties. In certain preferred embodiments the polymeric agent is a derivatized hydrophilic polymer with hydrophobic alkyl moieties Other types that may also a similar stabilizing effect are silicone copolymers and derivatized starch aluminum starch octenyl succinate (ASOS).
In an embodiment the polymeric agent is a polymeric surfactant Poloxamer. Poloxamer is a synthetic block copolymer of ethylene oxide and propylene, having the general formula of:




For the generic term “Poloxamer”, these copolymers are commonly named with the letter “P” (for Poloxamer) followed by three digits, the first two digits×100 give the approximate molecular mass of the polyoxypropylene core, and the last digit×10 gives the percentage polyoxyethylene content. For example, P407 is a Poloxamer with a polyoxypropylene molecular mass of 4,000 g/mol and a 70% polyoxyethylene content. A non limiting list is 124, 181, 182, 183, 184, 185, 188, 212, 215, 217, 231, 234, 235, 237, 238, 331, 333, 334, 3338, 335, 401, 402, 403 and 407.
Mixtures of the above polymeric agents are contemplated.
The concentration of the polymeric agent should be selected so that the composition, after filling into aerosol canisters, is flowable, and can be shaken in the canister. In one or more embodiments, the concentration of the polymeric agent is selected such that the viscosity of the composition, prior to filling of the composition into aerosol canisters, is about or less than 12,000 CPs, and more preferably, less than 10,000 CPs. Nevertheless where waxy substances are used in the composition especially in higher concentrations the viscosity may substantially exceed these figures.
In one or more embodiments the polymeric agent is a water miscible polymeric agent.
In one or more embodiments the polymeric agent is selected from at least one of the group consisting of pemulen, carboxymethyl cellulose (CMC), carbomer, klucel, hydroxyl propyl methyl cellulose and xantham gum.
Surface Active Agent
In some embodiments, the composition contains a surface-active agent. Surface-active agents (also termed “surfactants”) include any agent linking oil and water in the composition, in the form of emulsion. A surfactant's hydrophilic/lipophilic balance (HLB) describes the emulsifier's affinity toward water or oil. HLB is defined for non-ionic surfactants. The HLB scale ranges from 1 (totally lipophilic) to 20 (totally hydrophilic), with 10 representing an equal balance of both characteristics. Lipophilic emulsifiers form water-in-oil (w/o) emulsions; hydrophilic surfactants form oil-in-water (o/w) emulsions. The HLB of a blend of two emulsifiers equals the weight fraction of emulsifier A times its HLB value plus the weight fraction of emulsifier B times its HLB value (weighted average). In many cases a single surfactant may suffice. In other cases a combination of two or more surfactants is desired. Reference to a surfactant in the specification can also apply to a combination of surfactants or a surfactant system. As will be appreciated by a person skilled in the art which surfactant or surfactant system is more appropriate is related to the vehicle and intended purpose. In general terms a combination of surfactants is usually preferable where the vehicle is an emulsion. In an emulsion environment a combination of surfactants can be significant in producing breakable forms of good quality. It has been further discovered that the generally thought considerations for HLB values for selecting a surfactant or surfactant combination are not always binding for emulsions and that good quality foams can be produced with a surfactant or surfactant combination both where the HLB values are in or towards the lipophilic side of the scale and where the HLB values are in or towards the hydrophilic side of the scale. Surfactants also play a role in foam formation where the foamable formulation is a single phase composition.
According to one or more embodiments the composition contains a single surface active agent having an HLB value between about 2 and 9, or more than one surface active agent and the weighted average of their HLB values is between about 2 and about 9. Lower HLB values may in certain embodiments be more applicable to water in oil emulsions.
According to one or more embodiments the composition contains a single surface active agent having an HLB value between about 7 and 14, or more than one surface active agent and the weighted average of their HLB values is between about 7 and about 14. Mid range HLB values may in certain embodiments be more suitable for oil in water emulsions.
According to one or more other embodiments the composition contains a single surface active agent having an HLB value between about 9 and about 19, or more than one surface active agent and the weighted average of their HLB values is between about 9 and about 19.
Preferably, the composition contains a non-ionic surfactant. Nonlimiting examples of possible non-ionic surfactants include a polysorbate, polyoxyethylene (20) sorbitan monostearate, polyoxyethylene (20) sorbitan monooleate, a polyoxyethylene fatty acid ester, Myrj 45, Myrj 49, Myrj 52 and Myrj 59; a polyoxyethylene alkyl ether, polyoxyethylene cetyl ether, polyoxyethylene palmityl ether, polyethylene oxide hexadecyl ether, polyethylene glycol cetyl ether, steareths such as steareth 2, brij 21, brij 721, brij 38, brij 52, brij 56 and brij W1, a sucrose ester, a partial ester of sorbitol and its anhydrides, sorbitan monolaurate, sorbitan monolaurate, a monoglyceride, a diglyceride, isoceteth-20 and mono-, di- and tri-esters of sucrose with fatty acids. In certain embodiments, suitable sucrose esters include those having high monoester content, which have higher HLB values. In an embodiment the alkyl or fatty acid polyoxyalkylene ether or ester respectively is not less than C14.
In certain embodiments with wax as emollient, surfactants are selected which can provide a close packed surfactant layer separating the oil and water phases. To achieve such objectives combinations of at least two surfactants are selected. Preferably, they should be complex emulgators and more preferably they should both be of a similar molecular type. For example, a pair of ethers, like steareth 2 and steareth 21, or a pair of esters, such as, PEG-40 stearate and polysorbate 80 may be used. In Certain circumstances POE esters cannot be used and a combination of sorbitan laurate and sorbitan stearate or a combination of sucrose stearic acid ester mixtures and sodium laurate may be used. All these combinations due to their versatility and strength may also be used satisfactorily and effectively with wax formulations, although the amounts and proportion may be varied according to the formulation and its objectives as will be appreciated by a man of the art.
It has been discovered also that by using a derivatized hydrophilic polymer with hydrophobic alkyl moieties as a polymeric emulsifier such as pemulen it is possible to stabilize the emulsion better about or at the region of phase reversal tension. Other types of derivatized polymers like silicone copolymers, derivatized starch [Aluminum Starch Octenylsuccinate (ASOS)]/[DRY-FLO AF Starch], and derivatized dexrin may also a similar stabilizing effect.
A series of dextrin derivative surfactants prepared by the reaction of the propylene glycol polyglucosides with a hydrophobic oxirane-containing material of the glycidyl ether are highly biodegradable. [Hong-Rong Wang and Keng-Ming Chen, Colloids and Surfaces A: Physicochemical and Engineering Aspects Volume 281, Issues 1-3, 15 Jun. 2006, Pages 190-193].
Non-limiting examples of non-ionic surfactants that have HLB of about 7 to about 12 include steareth 2 (HLB ̃4.9); glyceryl monostearate/PEG 100 stearate (Av HLB ̃11.2); stearate Laureth 4 (HLB ̃9.7) and cetomacrogol ether (e.g., polyethylene glycol 1000 monocetyl ether).
Non-limiting examples of preferred surfactants, which have a HLB of 4-19 are set out in the Table below:














Surfactant
HLB



















steareth 2
~4.9



glyceryl monostearate/PEG 100 stearate
Av ~11.2



Glyceryl Stearate
~4



Steareth-21
~15.5



peg 40 stearate
~16.9



polysorbate 80
~15



sorbitan stearate
~4.7



laureth 4
~9.7



Sorbitan monooleate (span 80)
~4.3



ceteareth 20
~15.7



steareth 20
~15.3



ceteth 20
~15.7



Macrogol Cetostearyl Ether
~15.7



ceteth 2 (Lipocol C-2)
~5.3



PEG-30 Dipolyhydroxystearate
~5.5



sucrose distearate (Sisterna SP30)
~6



polyoxyethylene (100) stearate
~18.8










More exemplary stabilizing surfactants which may be suitable for use in the present invention are found below.
PEG-Fatty Acid Monoester Surfactants















Chemical name
Product example name
HLB




















PEG-30 stearate
Myrj 51
>10



PEG-40 laurate
Crodet L40 (Croda)
17.9



PEG-40 oleate
Crodet O40 (Croda)
17.4



PEG-45 stearate
Nikkol MYS-45 (Nikko)
18



PEG-50 stearate
Myrj 53
>10



PEG-100 stearate
Myrj 59, Arlacel 165 (ICI)
19










PEG-Fatty Acid Diester Surfactants:













Chemical name
Product example name
HLB

















PEG-4 dilaurate
Mapeg .RTM. 200 DL (PPG),
7



Kessco .RTM.PEG 200 DL (Stepan),



LIPOPEG 2-DL (Lipo Chem.)


PEG-4
distearate Kessco .RTM. 200 DS
5



(Stepan.sub)


PEG-32 dioleate
Kessco .RTM. PEG 1540 DO (Stepan)
15


PEG-400 dioleate
Cithrol 4DO series (Croda)
>10


PEG-400 disterate
Cithrol 4DS series (Croda)
>10


PEG-20 glyceryl oleate
Tagat .RTM. O (Goldschmidt)
>10









Transesterification Products of Oils and Alcohols













Chemical name
Product example name
HLB







PEG-30 castor oil
Emalex C-30 (Nihon Emulsion)
11


PEG-40 hydrogenated
Cremophor RH 40 (BASF),
13


castor oil
Croduret (Croda), Emulgin



HRE 40 (Henkel)









Polyglycerized Fatty Acids, Such as:
















Chemical name
Product example name
LB









Polyglyceryl-6
Caprol .RTM. 6G20 (ABITEC);
8.5



dioleate
PGO-62 (Calgene), PLUROL




OLEIQUE CC 497 (Gattefosse)Hodag










PEG-Sorbitan Fatty Acid Esters
















Chemical name
Product example name
HLB









PEG-20 sorbitan
Tween-20 (Atlas/ICI), Crillet 1
17



monolaurate
(Croda), DACOL MLS 20




(Condea)



PEG-20 sorbitan
Tween 40 (Atlas/ICI), Crillet 2
16



Monopalmitate
(Croda)



PEG-20 sorbitan
Tween-60 (Atlas/ICI), Crillet 3
15



monostearate
(Croda)



PEG-20 sorbitan
Tween-80 (Atlas/ICI), Crillet 4
15



monooleate
(Croda)










Polyethylene Glycol Alkyl Ethers













Chemical name
Product example name
HLB

















PEG-2 oleyl ether
oleth-2 Brij 92/93 (Atlas/ICI)
4.9


PEG-3 oleyl ether
oleth-3 Volpo 3 (Croda)
<10


PEG-5 oleyl ether
oleth-5 Volpo 5 (Croda)
<10


PEG-10 oleyl ether
oleth-10 Volpo 10 (Croda), Brij
12



96/97 (Atlas/ICI)


PEG-20 oleyl ether
oleth-20 Volpo 20 (Croda), Brij
15



98/99 (Atlas/ICI)


PEG-4 lauryl ether
laureth-4Brij 30 (Atlas/ICI)
9.7


PEG-23 lauryl ether
laureth-23Brij 35 (Atlas/ICI)
17


PEG-10 stearyl ether
Brij 76 (ICI)
12


PEG-2 cetyl ether
Brij 52 (ICI)
5.3









Sugar Ester Surfactants
















Chemical name
Product example name
HLB









Sucrose distearate
Sisterna SP50, Surfope 1811
11










Sorbitan Fatty Acid Ester Surfactants













Chemical name
Product example name
HLB







Sorbitan monolaurate
Span-20 (Atlas/ICI), Crill 1
8.6



(Croda), Arlacel 20 (ICI)


Sorbitan monopalmitate
Span-40 (Atlas/ICI), Crill 2
6.7



(Croda), Nikkol SP-10 (Nikko)


Sorbitan monooleate
Span-80 (Atlas/ICI), Crill 4
4.3



(Croda), Crill 50 (Croda)


Sorbitan monostearate
Span-60 (Atlas/ICI), Crill 3
4.7



(Croda), Nikkol SS-10 (Nikko)









In one or more embodiments the surface active agent is a combination of two or more surface active agents that can be more effective than a single surfactant and provides a more stable emulsion or improved foam quality than a single surfactant. For example and by way of non-limiting explanation it has been found that by choosing say two surfactants, one hydrophobic and the other hydrophilic the combination can produce a more stable emulsion than a single surfactant. Preferably, the complex emulgator comprises a combination of surfactants wherein there is a difference of about 4 or more units between the HLB values of the two surfactants or there is a significant difference in the chemical nature or structure of the two or more surfactants. Without being bound by any theory by appropriate selection of a liquid wax and or a solid wax to use with a surfactant pair (and vice versa) the packing of the surfactant layer or interphase can be effected and may result in a less packed and more disrupted layer or interphase by choosing a branched and or unsaturated wax or a more packed less disrupted layer or interphase by selecting straight chain saturated waxes. Nevertheless, an appropriate single surfactant with a liquid wax or a solid wax or mixtures thereof can also have a similar effect on the surfactant layer or interphase.
Specific non limiting examples of surfactant systems are, combinations of polyoxyethylene alkyl ethers, such as Brij 59/Brij 10; Brij 52/Brij 10; Steareth 2/Steareth 20; Steareth 2/Steareth 21 (Brij 72/Brij 721); combinations of polyoxyethylene stearates such as Myrj 52/Myrj 59; combinations of sucrose esters, such as Surphope 1816/Surphope 1807; combinations of sorbitan esters, such as Span 20/Span 80; Span 20/Span 60; combinations of sucrose esters and sorbitan esters, such as Surphope 1811 and Span 60; combinations of liquid polysorbate detergents and PEG compounds, such as Tween 80/PEG-40 stearate; methyl glucaso sequistearate; polymeric emulsifiers, such as Permulen (TRI or TR2); liquid crystal systems, such as Arlatone (2121), Stepan (Mild RM1), Nikomulese (41) and Montanov (68) and the like.
In certain embodiments the surfactant is preferably one or more of the following: a combination of steareth-2 and steareth-21 on their own or in combination with glyceryl monostearate (GMS); in certain other embodiments the surfactant is a combination of polysorbate 80 and PEG-40 stearate. In certain other embodiments the surfactant is a combination of glyceryl monostearate/PEG 100 stearate. In certain other embodiments the surfactant is a combination of two or more of stearate 21, PEG 40 stearate, and polysorbate 80. In certain other embodiments the surfactant is a combination of two or more of laureth 4, span80, and polysorbate 80. In certain other embodiments the surfactant is a combination of two or more of GMS and ceteareth. In certain other embodiments the surfactant is a combination of two or more of steareth 21, ceteareth 20, ceteth 2 and laureth 4 In certain other embodiments the surfactant is a combination of ceteareth 20 and polysorbate 40 stearate. In certain other embodiments the surfactant is a combination of span 60 and GMS. In certain other embodiments the surfactant is a combination of two or all of PEG 40 stearate, sorbitan stearate and polysorbate 60
In certain other embodiments the surfactant is one or more of sucrose stearic acid esters, sorbitan laureth, and sorbitan stearate.
Without being bound by any particular theory or mode of operation, it is believed that the use of non-ionic surfactants with significant hydrophobic and hydrophilic components, increase the emulsifier or foam stabilization characteristics of the composition. Similarly, without being bound by any particular theory or mode of operation, using combinations of surfactants with high and low HLB's to provide a relatively close packed surfactant layer may strengthen the emulsion.
In one or more embodiments the stability of the composition can be improved when a combination of at least one non-ionic surfactant having HLB of less than 9 and at least one non-ionic surfactant having HLB of equal or more than 9 is employed. The ratio between the at least one non-ionic surfactant having HLB of less than 9 and the at least one non-ionic surfactant having HLB of equal or more than 9, is between 1:8 and 8:1, or at a ratio of 4:1 to 1:4. The resultant HLB of such a blend of at least two emulsifiers is preferably between about 9 and about 14.
Thus, in an exemplary embodiment, a combination of at least one non-ionic surfactant having HLB of less than 9 and at least one non-ionic surfactant having HLB of equal or more than 9 is employed, at a ratio of between 1:8 and 8:1, or at a ratio of 4:1 to 1:4, wherein the HLB of the combination of emulsifiers is preferably between about 5 and about 18.
In certain cases, the surface active agent is selected from the group of cationic, zwitterionic, amphoteric and ampholytic surfactants, such as sodium methyl cocoyl taurate, sodium methyl oleoyl taurate, sodium lauryl sulfate, triethanolamine lauryl sulfate and betaines.
Many amphiphilic molecules can show lyotropic liquid-crystalline phase sequences depending on the volume balances between the hydrophilic part and hydrophobic part. These structures are formed through the micro-phase segregation of two incompatible components on a nanometer scale. Soap is an everyday example of a lyotropic liquid crystal. Certain types of surfactants tend to form lyotropic liquid crystals in emulsions interface (oil-in-water) and exert a stabilizing effect
In one or more embodiments the surfactant is a surfactant or surfactant combination is capable of or which tends to form liquid crystals. Surfactants which tend to form liquid crystals may improve the quality of foams. Non limiting examples of surfactants with postulated tendency to form interfacial liquid crystals are: phospholipids, alkyl glucosides, sucrose esters, sorbitan esters.
In one or more embodiments the at least one surface active agent is liquid.
In one or more embodiments the liquid surfactant is a polysorbate, preferably polysorbate 80 or 60.
In one or more embodiments the at least one surface active agent is solid, semi solid or waxy.
In one or more embodiments the surfactant can be, a surfactant system comprising of a surfactant and a co surfactant, a waxy emulsifier, a liquid crystal emulsifier, an emulsifier which is solid or semi solid at room temperature and pressure, or combinations of two or more agents in an appropriate proportion as will be appreciated a person skilled in the art. Where a solid or semi solid emulsifier combination is used it can also comprise a solid or semi solid emulsifier and a liquid emulsifier.
In one or more embodiments, the surface-active agent includes at least one non-ionic surfactant. Ionic surfactants are known to be irritants. Therefore, non-ionic surfactants are preferred in applications including sensitive tissue such as found in most mucosal tissues, especially when they are infected or inflamed. Non-ionic surfactants alone can provide formulations and foams of good or excellent quality in the carriers and compositions.
Thus, in some embodiments, the composition contains a non-ionic surfactant. In other embodiments the composition includes a mixture of non-ionic surfactants as the sole surface active agent. Yet, in additional embodiments, the foamable composition includes a mixture of at least one non-ionic surfactant and at least one ionic surfactant in a ratio in the range of about 100:1 to 6:1. In one or more embodiments, the non-ionic to ionic surfactant ratio is greater than about 6:1, or greater than about 8:1; or greater than about 14:1, or greater than about 16:1, or greater than about 20:1. In further embodiments, surface active agent comprises a combination of a non-ionic surfactant and an ionic surfactant, at a ratio of between 1:1 and 20:1.
In one or more embodiments, a combination of a non-ionic surfactant and an ionic surfactant (such as sodium lauryl sulphate and cocamidopropylbetaine) is employed, at a ratio of between 1:1 and 20:1, or at a ratio of 4:1 to 10:1; for example, about 1:1, about 4:1, about 8:1, about 12:1, about 16:1 and about 20:1 or at a ratio of 4:1 to 10:1, for example, about 4:1, about 6:1, about 8:1 and about 10:1.
In selecting a suitable surfactant or combination thereof it should be borne in mind that the upper amount of surfactant that may be used may be limited by the shakability of the composition. If the surfactant is non liquid, it can make the formulation to viscous or solid. This can be particularly significant if the formulation has high molecular weight, e.g., a high molecular weight PEG or polymeric agents or petroleum or if the surfactants are large. Solvents and polymeric agents which have high molecular weight and are very viscous or solid or waxy (e.g., Peg 1500, 2000, etc. or petrolatum) can exacerbate the effect of a waxy or solid surfactant on shakability or flowability. In general terms, as the amount of non-liquid surfactant is increased the shakability of the formulation reduces until a limitation point is reached where the formulation becomes non shakable and unsuitable. Thus in one embodiment, an effective amount of surfactant may be used provided the formulation remains shakable. In other certain exceptional embodiments the upper limit may be determined by flowability such as in circumstances where the composition is marginally or apparently non-shakable. The formulation is sufficiently flowable to be able to flow through an actuator valve and be released and still expand to form a good quality foam.
In certain embodiments the amount of surfactant or combination of surfactants may be between about 0.05% to less than about 20%; between about 0.05% to about 15%. or between about 0.05% to about 10%. Although these higher amounts of surfactants may be used nevertheless the amount of surfactants should be reduced or kept low to avoid potential irritation; depletion of fatty substances from the skin; and dry skin from repeated use of the formulations. Thus in some embodiments the concentration of surface active agent is lower, e.g., between about 0.2% and about 8%. In a further embodiment the concentration of surface active agent is between about 1% and about 5%. By selecting hydrophobic waxes which can also function as a foam adjuvant in the formulation or as a co surfactant giving support to the surfactant in stabilizing the emulsion and or in producing better foam it is possible to use a smaller amount of surfactant. In a preferred embodiment the hydrophobic waxes are a mixture of a liquid and a solid hydrophobic wax at least one of which can function as a foam adjuvant. In a more preferred embodiment the formulation comprises a liquid and a solid wax both of which can also function as a foam adjuvant.
High levels of surfactants which can form a mesomorphic phase should be avoided. Thus, in an embodiment the amount of surfactant or combination of surfactants is less than that needed to form a mesomorphic phase.
In some embodiments, it is desirable that the surface active agent does not contain a polyoxyethylene (POE) moiety, such as polysorbate surfactants, POE fatty acid esters, and POE alkyl ethers, because the active agent is incompatible with such surface active agents. For example, the active agent pimecrolimus is not stable the presence of POE moieties, yet benefits greatly from the use of dicarboxylic esters as penetration enhancers. In such cases, alternative surface active agents are employed. In an exemplary manner, POE—free surfactants include non-ethoxylated sorbitan esters, such as sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate, sorbitan trioleate, sorbitan monolaurate and sorbitan sesquioleate; glycerol fatty acid esters, such as glycerol monostearate and glycerol monooleate; mono-, di- and tri-esters of sucrose with fatty acids (sucrose esters), sucrose stearate, sucrose distearate sucrose palmitate and sucrose laurate; and alkyl polyglycosides, such as lauryl diglucoside. In an embodiment the surfactant is not a polyoxyethylene fatty acid ester. In an embodiment the surfactant is not a polyoxyethylene alkyl ether. In an embodiment the surfactant is not a polyoxyethylene lauryl ether.
If the composition as formulated is a substantially non shakable composition it is nevertheless possible as an exception in the scope for the formulation to be flowable to a sufficient degree to be able to flow through an actuator valve and be released and still expand to form a good quality foam. This surprising and unusual exception may be due one or more of a number of factors such as the high viscosity, the softness, the lack of crystals, the pseudoplastic or semi pseudo plastic nature of the composition and the dissolution of the propellant into the composition.
In one or more embodiments, the surface-active agent includes mono-, di- and tri-esters of sucrose with fatty acids (sucrose esters), prepared from sucrose and esters of fatty acids or by extraction from sucro-glycerides. Suitable sucrose esters include those having high monoester content, which have higher HLB values.
Phase Inversion and Tension
Phase inversion is a factor in the preparation and stabilization of emulsions and can be both an aid and a detriment. Phase inversion involves the change of emulsion type from o/w to w/o or vice versa. Prior to phase inversion occurring there is a tension in the emulsion which if destabilized or driven will lead to phase inversion and if controlled or ameliorated or dissipated will result in a more stable emulsion. The occurrence of phase inversion during preparation can be a sign of instability. If controlled, it can result in a finer product but if due to other factors after the emulsion was prepared it can cause problems. Inversion can occur by for example adding calcium chloride to an o/w emulsion stabilized with sodium stearate to form calcium stearate. Inversion can also occur as the product of changes to the phase-volume ratio. For example if a small amount of water is added to surfactant mixed with oil and agitated a w/o emulsion is formed. As the amount of water added is gradually increased a point will be reached where the water and emulsifier envelop the oil as small droplets to form an o/w emulsion. The amount of each ingredient including the surfactants will have their part to play in the phenomenon.
Substantially Alcohol-Free
According to one or more embodiments, the foamable composition is substantially alcohol-free, i.e., free of short chain alcohols. Short chain alcohols, having up to 5 carbon atoms in their carbon chain skeleton and one hydroxyl group, such as ethanol, propanol, isopropanol, butaneol, iso-butaneol, t-butaneol and pentanol, are considered less desirable solvents or polar solvents due to their skin-irritating effect. Thus, the composition is substantially alcohol-free and includes less than about 5% final concentration of lower alcohols, preferably less than about 2%, more preferably less than about 1%.
Substantially Non Aqueous
In certain cases, the active agent degrades in the presence of water, and therefore, in such cases the present of water in the composition is not desirable. Thus, in certain preferred embodiments, the composition is substantially non-aqueous. The term “substantially non-aqueous” or “substantially waterless” is intended to indicate that the composition has a water content below about 25%.
Shakability
‘Shakability’ means that the composition contains some or sufficient flow to allow the composition to be mixed or remixed on shaking. That is, it has fluid or semi fluid properties. In some very limited cases it may exceptionally be possible to have a foamable composition which is flowable but not apparently shakable.
Breakability
A breakable foam is one that is thermally stable, yet breaks under sheer force.
The breakable foam is not “quick breaking”, i.e., it does not readily collapse upon exposure to body temperature environment. Sheer-force breakability of the foam is clearly advantageous over thermally induced breakability, since it allows comfortable application and well directed administration to the target area.
Modulating Agent
The term modulating agent is used to describe an agent which can improve the stability of or stabilize a foamable carrier or composition and or an active agent by modulating the effect of a substance or residue present in the carrier or composition.
In one or more embodiments the modulating agent is used in a water in oil or oil in water emulsion
In certain embodiments the substance or residue may for example be acidic or basic and potentially alter pH in an emulsion environment or it may be one or more metal ions which may act as a potential catalyst in an emulsion environment.
In one or more embodiments the modulating agent is used to describe an agent which can affect pH in an aqueous solution. The agent can be any of the known buffering systems used in pharmaceutical or cosmetic formulations as would be appreciated by a man of the art. It can also be an organic acid, a carboxylic acid, a fatty acid an amino acid, an aromatic acid, an alpha or beta hydroxyl acid an organic base or a nitrogen containing compound.
In one or more further embodiments the modulating agent is used to describe an agent, which is a chelating or sequestering or complexing agent that is sufficiently soluble or functional in the solvent to enable it to “mop up” or “lock” metal ions.
In an embodiment modulating agent is used to describe an agent which can effect pH in an aqueous solution the term modulating agent more particularly means an acid or base or buffer system or combinations thereof, which is introduced into or is present in and acts to modulate the ionic or polar characteristics and any acidity or basesity balance of an emulsion carrier, composition, foamable carrier or foamable composition or resultant foam.
In one or more embodiments the composition does not contain a modulating agent. In other embodiments the composition does not contain a neutralizing agent. In further embodiments the composition is not partially neutralized.
In one or more embodiments the modulating agent comprises an organic compound.
In one or more embodiments the modulating agent is used to acidify the formulation. In one embodiment it is used to provide an acidic pH, which is similar to or within the pH range found in healthy skin or in a healthy body cavity.
In an embodiment the vehicles and foam formulations are further acidified with an organic acid, preferably a liquid organic acid, more preferably an alpha hydroxy acid.
In one or more embodiments the chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), hydroxyethylenediaminetriacetic acid (HEDTA), nitrilotriacetic acid (NTA), O,O′-bis(2-aminoethyl)ethyleneglycol-N,N,N′,N′-tetraacetic acid (EGTA), trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid (CyDTA) or a pharmaceutically acceptable salt thereof (normally as a sodium salt), more preferably EDTA, HEDTA and their salts; most preferably EDTA and its salts.
In one or more embodiments a non limiting example of the chelating agent is EDTA. Typically, the chelating and sequestering agent is present in the composition at a level of up to about 5.0%, preferably 1.0 percent, by weight, of the composition.
In one or more embodiments the modulating agent may also be a preservative or an antioxidant or an ionization agent. Any preservative, antioxidant or ionization agents suitable for pharmaceutical or cosmetic application may be used. Non limiting examples of antioxidants are tocopherol succinate, propyl galate, butylated hydroxy toluene and butyl hydroxy anisol. Ionization agents may be positive or may be negative depending on the environment and the active agent or composition that is to be protected. Ionization agents may for example act to protect or reduce sensitivity of active agents. Non limiting examples of positive ionization agents are benzyl conium chloride, and cetyl pyridium chloride. Non limiting examples of negative ionization agents are sodium lauryl sulphate, sodium lauryl lactylate and phospholipids.
Humectant
A humectant is a substance that helps retain moisture and also prevents rapid evaporation. Non limiting examples are propylene glycol, propylene glycol derivatives, glycerin, hydrogenated starch hydrosylate, hydrogenated lanolin, lanolin wax, D mannitol, sorbitol, sodium 2-pyrrolidone-5-carboxylate, sodium lactate, sodium PCA, soluble collagen, dibutyl phthalate, and gelatin. Other examples may be found in the Handbook of Pharmaceutical Additives published by Gower.
Moisturizers
A moisturizer, is a substance that helps retain moisture or add back moisture to the skin. Examples include, without limitation, allantoin, petrolatum, urea, lactic acid, sodium PCV, glycerin, shea butter, caprylic/capric/stearic triglyceride, candelilla wax, propylene glycol, lanolin, hydrogenated oils, squalene, sodium hyaluronate and lysine PCA. Other examples may be found in the Handbook of Pharmaceutical Additives published by Gower.
Pharmaceutical compositions may in one or more embodiments usefully comprise in addition a humectant or a moisturizer or combinations thereof.
Polar Solvent
Optionally, the foamable vehicle further includes at least one polar solvent.
A “polar solvent” is an organic solvent, typically soluble in both water and oil. Certain polar solvents, for example propylene glycol and glycerin, possess the beneficial property of a humectant.
In one or more embodiments, the polar solvent is a humectant.
In one or more embodiments, the polar solvent is a polyol. Polyols are organic substances that contain at least two hydroxy groups in their molecular structure.
In one or more embodiments, the polar solvent contains an diol (a compound that contains two hydroxy groups in its molecular structure), such as propylene glycol (e.g., 1,2-propylene glycol and 1,3-propylene glycol), butanediol (e.g., 1,4-butaneediol), butanediol (e.g., 1,3-butaneediol and 1,4-butenediol), butynediol, pentanediol (e.g., 1,5-pentanediol), hexanediol (e.g., 1,6-hexanediol), octanediol (e.g., 1,8-octanediol), neopentyl glycol, 2-methyl-1,3-propanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol and dibutylene glycol.
In one or more embodiments, the polar solvent contains a triol (a compound that contains three hydroxy groups in its molecular structure), such as glycerin and 1,2,6-Hexanetriol.
Other non-limiting examples of polar solvents include pyrrolidones, (such as N-methyl-2-pyrrolidone and 1-methyl-2-pyrrolidinone), dimethyl isosorbide, 1,2,6-hexapetriol, dimethyl sulfoxide (DMSO), ethyl proxitol, dimethylacetamide (DMAc) and alpha hydroxy acids, such as lactic acid and glycolic acid.
According to still other embodiments, the polar solvent is a polyethylene glycol (PEG) or PEG derivative that is liquid at ambient temperature, including PEG200 (MW (molecular weight) about 190-210 kD), PEG300 (MW about 285-315 kD), PEG400 (MW about 380-420 kD), PEG600 (MW about 570-630 kD) and higher MW PEGs such as PEG 4000, PEG 6000 and PEG 10000 and mixtures thereof.
Polar solvents are known to enhance the penetration of active agent into the skin and through the skin, and therefore, their inclusion in the composition can be desirable, despite their undesirable skin drying and irritation potential. There is at one level a commonality between the different polar solvents and their penetration enhancement properties. Lower molecular weight alcohols can sometimes be more potent as a solvent, for example by extracting lipids from the skin layers more effectively, which characteristic can adversely affect the skin structure and cause dryness and irritation. Therefore the selection of lower molecular weight alcohols is ideally avoided.
Polar solvents, such as detailed below possess high solubilizing capacity and contribute to the skin penetration of an active agent. Non limiting examples include dimethyl isosorbide polyols, such as glycerol (glycerin), propylene glycol, hexylene glycol, diethylene glycol, propylene glycol n-alkanols, terpenes, di-terpenes, tri-terpenes, limonene, terpene-ol, 1-menthol, dioxolane, ethylene glycol, other glycols, oleyl alcohol, alpha-hydroxy acids, such as lactic acid and glycolic acid, sulfoxides, such as dimethylsulfoxide (DMSO), dimethylformanide, methyl dodecyl sulfoxide, dimethylacetamide, azone (1-dodecylazacycloheptan-2-one), 2-(n-nonyl)-1,3-dioxolane, alkanols, such as dialkylamino acetates, and admixtures thereof. In certain preferred embodiments, the polar solvent is selected from the group consisting of dimethyl isosorbide glycerol (glycerin), propylene glycol, hexylene glycol, terpene-ol, oleyl alcohol, lactic acid and glycolic acid.
Skin Penetration Enhancer
In some embodiments, the compositions described herein include one or more skin penetration enhancers. A “skin penetration enhancer”, also termed herein “penetration enhancer,” is an organic solvent, typically soluble in both water and oil. Examples of penetration enhancer include polyols, such as glycerol (glycerin), propylene glycol, hexylene glycol, diethylene glycol, propylene glycol n-alkanols, terpenes, di-terpenes, tri-terpenes, terpen-ols, limonene, terpene-ol, 1-menthol, dioxolane, ethylene glycol, hexylene glycol, other glycols, sulfoxides, such as dimethylsulfoxide (DMSO), dimethylformanide, methyl dodecyl sulfoxide, dimethylacetamide, dimethylisosorbide, monooleate of ethoxylated glycerides (with 8 to 10 ethylene oxide units), azone (1-dodecylazacycloheptan-2-one), 2-(n-nonyl)-1,3-dioxolane, esters, such as isopropyl myristate/palmitate, ethyl acetate, butyl acetate, methyl proprionate, capric/caprylic triglycerides, octylmyristate, dodecyl-myristate; myristyl alcohol, lauryl alcohol, lauric acid, lauryl lactate ketones; amides, such as acetamide oleates such as triolein; various alkanoic acids such as caprylic acid; lactam compounds, such as azone; alkanols, such as dialkylamino acetates, and admixtures thereof.
According to one or more embodiments, the penetration enhancer is a polyethylene glycol (PEG) or PEG derivative that is liquid at ambient temperature
Potent Solvent
In one or more embodiments, the foamable composition includes a potent solvent, in addition to or in place of one of the hydrophobic solvents, polar solvents or emollients of the composition. A potent solvent is a solvent other than mineral oil that solubilizes a specific active agent substantially better than a hydrocarbon solvent such as mineral oil or petrolatum. For example, a potent solvent solubilizes the active agent 5 fold better than a hydrocarbon solvent; or even solubilizes the active agent 10-fold better than a hydrocarbon solvent.
In one or more embodiments, the composition includes at least one active agent in a therapeutically effective concentration; and at least one potent solvent in a sufficient amount to substantially solubilize the at least one active agent in the composition. The term “substantially soluble” means that at least 95% of the active agent has been solubilized, i.e., 5% or less of the active agent is present in a solid state. In one or more embodiments, the concentration of the at least one potent solvent is more than about 40% of the at least one solvent of the composition; or even more than about 60%.
Non-limiting examples of pairs of active agent and potent solvent include: Betamethasone valerate: Practically insoluble in mineral oil (<0.01%); soluble more than 1% in glycofurol; Hydrocortisone butyrate: Practically insoluble in mineral oil (<0.01%); soluble more than 1% in glycofurol; Metronidazole: Practically insoluble in mineral oil (<0.01%); soluble more than 1% in dimethyl isosorbide; Ketoconazole: Practically insoluble in mineral oil (<0.01%); soluble more than 1% in glycofurol, propylene glycol and dimethyl isosorbide; Mupirocin: Practically insoluble in mineral oil (<0.01%); soluble more than 1% in glycofurol, hexylene glycol, dimethyl isosorbide, propylene glycol and polyethylene glycol 400 (PEG 400); Meloxicam, a nonsteroidal anti-inflammatory agent: Practically insoluble in mineral oil (<0.001%); soluble in propylene glycol: 0.3 mg/mL; and in PEG 400: 3.7 mg/mL; and Progesterone: Practically insoluble in mineral oil (<0.001%); soluble in PEG 400: 15.3 mg/mL.
A non-limiting exemplary list of solvents that can be considered as potent solvents includes polyethylene glycol, propylene glycol, hexylene glycol, butanediols and isomers thereof, glycerol, benzyl alcohol, DMSO, ethyl oleate, ethyl caprylate, diisopropyl adipate, dimethylacetamide, N-methylpyrrolidone, N-hydroxyethylpyrrolidone, polyvinylpyrrolidone, isosorbide derivatives, such as dimethyl isosorbide, glycofurol and ethoxydiglycol (transcutol) and laurocapram.
The use of a potent solvent in a foam composition provides an improved method of delivering poorly soluble therapeutic agents to a target area. It is known that low drug solubility results in poor bioavailability, leading to decreased effectiveness of treatment. Foam compositions, for which the solvent includes a potent solvent, increase the levels of the active agent in solution and thus, provide high delivery and improved therapy.
Potent solvents, as defined herein, are usually liquid. Formulations comprising potent solvents and active agents are generally disadvantageous as therapeutics, since their usage involves unwanted dripping and inconvenient method of application; resulting in inadequate dosing. Surprisingly, the foams, which are drip-free, provide a superior vehicle for such active agents, enabling convenient usage and accurate effective dosing.
In one or more embodiments the present invention the foamable pharmaceutical composition may additionally include a mixture of two or more of the solvents selected from the group of hydrophobic solvents, silicone oils, emollients, polar solvents and potent solvents in an appropriate proportion as would be appreciated to a person skilled in the art.
In one or more embodiments, the PPG alkyl ether may act as a potent solvent
Additional Components
In an embodiment, a composition includes one or more additional components. Such additional components include but are not limited to anti perspirants, anti-static agents, buffering agents, bulking agents, chelating agents, cleansers, colorants, conditioners, deodorants, diluents, dyes, emollients, fragrances, hair conditioners, humectants, pearlescent aids, perfuming agents, permeation enhancers, pH-adjusting agents, preservatives, protectants, skin penetration enhancers, softeners, solubilizers, sunscreens, sun blocking agents, sunless tanning agents, viscosity modifiers and vitamins. As is known to one skilled in the art, in some instances a specific additional component may have more than one activity, function or effect.
Propellants
Suitable propellants include volatile hydrocarbons such as butane, propane, isobutane and fluorocarbon gases, or mixtures thereof.
In an embodiment the propellant is AP 70 which is a mixture of propane, isobutene and butane.
The propellant makes up about 5-25 wt % of the foamable composition (i.e., the ratio of the propellant to components that make up the foamable vehicle range from about 5:100 to about 25:100). In some circumstances the propellant may be up to about 35% or as low as about 3% (i.e., the ratio of the propellant to components that make up the foamable vehicle is from about 3:100 to about 35:100). The propellants are used to generate and administer the foamable composition as a foam. The total composition including propellant, foamable compositions and optional ingredients is referred to as the foamable composition.
Alcohol and organic solvents render foams inflammable. It has been surprisingly discovered that fluorohydrocarbon propellants, other than chloro-fluoro carbons (CMOs), which are non-ozone-depleting propellants, are particularly useful in the production of a non-flammable foamable composition. A test according to European Standard prEN 14851, titled “Aerosol containers—Aerosol foam flammability test” revealed that compositions containing an organic carrier that contains a hydrophobic organic carrier and/or a polar solvent, which are detected as inflammable when a hydrocarbon propellant is used, become non-flammable, while the propellant is an HFC propellant.
Such propellants include, but are not limited to, hydrofluorocarbon (HFC) propellants, which contain no chlorine atoms, and as such, fall completely outside concerns about stratospheric ozone destruction by chlorofluorocarbons or other chlorinated hydrocarbons. Exemplary non-flammable propellants according to this aspect of the invention include propellants made by DuPont under the registered trademark Dymel, such as 1,1,1,2 tetrafluoroethane (Dymel 134), and 1,1,1,2,3,3,3 heptafluoropropane (Dymel 227). HFCs possess Ozone Depletion Potential of 0.00 and thus, they are allowed for use as propellant in aerosol products.
Notably, the stability of foamable emulsions including HFC as the propellant can be improved in comparison with the same composition made with a hydrocarbon propellant.
In one or more embodiments foamable compositions comprise a combination of a HFC and a hydrocarbon propellant such as n-butane or mixtures of hydrocarbom propellants such as propane, isobutane and butane. In one or more embodiments the hydrocarbon mixture of propane, isobutane and butane is AP70.
In one or more embodiments the foamable compositions are not self foaming.
Microemulsions and Nanoemulsions
In some embodiments, the compositions described herein are microemulsions or nanoemulsions. Microemulsions and nanoemulsion are monophasic, transparent (or slightly translucent) dispersions of oil and water. Unlike conventional emulsions, microemulsions and nanoemulsion are thermodynamically stable, making them a favorable vehicle for pharmaceutical compositions, which have to maintain stability for long periods of time. They and a method of manufacture are more particularly described in US2006/0233721 which is incorporated herein by way of reference. As will be appreciated by a person of skill in the art the methodology may be adapted according to the type of carrier composition.
Aging
In order to project the potential shelf life and stability of the compositions and their ingredients particularly active or benefit agents the compositions can subjected to a number of tests, including centrifugation to look for resistance to creaming, phase separation; one or more freeze thaw cycles, standing at room and higher temperatures as an indicator of resistance to aging.
Composition and Foam Physical Characteristics and Advantages
A pharmaceutical or cosmetic composition manufactured using the foamable carrier is very easy to use. When applied onto the afflicted body surface of mammals, i.e., humans or animals, it is in a foam state, allowing free application without spillage. Upon further application of a mechanical force, e.g., by rubbing the composition onto the body surface, it freely spreads on the surface and is rapidly absorbed.
The foamable composition is stable, having an acceptable shelf-life of at least one year, or preferably, at least two years at ambient temperature, as revealed in accelerated stability tests. The foamable compositions according to the present invention are stable. Following accelerated stability studies, they demonstrate desirable texture; they form fine bubble structures that do not break immediately upon contact with a surface, spread easily on the treated area and absorb quickly.
The composition should also be free flowing, to allow it to flow through the aperture of the container, e.g., and aerosol container, and create an acceptable foam.
Foam quality can be graded as follows:
Grade E (excellent): very rich and creamy in appearance, does not show any bubble structure or shows a very fine (small) bubble structure; does not rapidly become dull; upon spreading on the skin, the foam retains the creaminess property and does not appear watery.
Grade G (good): rich and creamy in appearance, very small bubble size, “dulls” more rapidly than an excellent foam, retains creaminess upon spreading on the skin, and does not become watery.
Grade FG (fairly good): a moderate amount of creaminess noticeable, bubble structure is noticeable; upon spreading on the skin the product dulls rapidly and becomes somewhat lower in apparent viscosity.
Grade F (fair): very little creaminess noticeable, larger bubble structure than a “fairly good” foam, upon spreading on the skin it becomes thin in appearance and watery.
Grade P (poor): no creaminess noticeable, large bubble structure, and when spread on the skin it becomes very thin and watery in appearance.
Grade VP (very poor): dry foam, large very dull bubbles, difficult to spread on the skin.
Topically administrable foams are typically of quality grade E or G, when released from the aerosol container. Smaller bubbles are indicative of more stable foam, which does not collapse spontaneously immediately upon discharge from the container. The finer foam structure looks and feels smoother, thus increasing its usability and appeal.
As further aspect of the foam is breakability. The breakable foam is thermally stable, yet breaks under sheer force. Sheer-force breakability of the foam is clearly advantageous over thermally induced breakability. Thermally sensitive foams immediately collapse upon exposure to skin temperature and, therefore, cannot be applied on the hand and afterwards delivered to the afflicted area.
Another property of the foam is specific gravity, as measured upon release from the aerosol can. Typically, foams have specific gravity of less than 0.12 g/mL; or less than 0.10 g/mL; or less than 0.08 g/mL, depending on their composition and on the propellant concentration.
Pharmaceutical Composition
The foamable carrier is an ideal vehicle for active pharmaceutical ingredients and active cosmetic ingredients. In the context, active pharmaceutical ingredients and active cosmetic ingredients are collectively termed “active agent” or “active agents.” The active agents can be used in the formulation as a suspended solid or in solution, alone or in combination with other active agents.
In one or more embodiments the active ingredient is an immune response modifier or antiviral agent selected from the group consisting of imiquimod, resiquimod, and gardiquimod.
Imiquimod (4-Amino-1-isobutyl-1H-imidazo[4,5-c]quinoline) an imidazoquinoline amine, is an immune response modifier used topically in the treatment of external genital and perianal warts, superficial basal cell carcinomas, and actinic keratoses. It is applied as a 5% cream, with the frequency and period varying depending on the disease. Imiquimod is under investigation for the treatment of Bowen's disease and of other squamous cell carcinomas. Adverse effects after topical application of imiquimod include local skin erosion, erythema, excoriation, flaking, and oedema. There have been reports of localised hypopigmentation and hyperpigmentation. Skin reactions away from the site of application have been reported. Imiquimod is used topically for the treatment of external genital and perianal exophytic warts (condylomata acuminata) caused by human papillomavirus (HPV). Potentially it may have application for treating body cavity warts urethral, intravaginal, cervical, rectal, intra-anal, or oral HPV warts. Imiquimod has been used topically for the treatment of molluscum contagiosum and for the treatment of actinic keratoses. It may also have potential for the topical treatment of verruca vulgaris (common warts). Alternative regimens include intralesional interferon alfa and laser surgery. There is some evidence that warts located on moist surfaces and/or in intertriginous areas appear to respond better to topical treatments. On this basis in one or more embodiments, the imiquimod formulation further comprises a moisturizer and or a humectant.
Other members of the imiquimod family are resiquimod (used against herpes simplex virus infections, including genital herpes and is a potential treatment of various other diseases, including other viral infections and eczema and as a vaccine adjuvant) and gardiquimod (a potential antiviral).
In one or more embodiments, imiquimod is the active ingredient. It can be used in the formulation as a suspended solid or in solution, alone or in combination with other active agents. As is known to one skilled in the art, in some instances a specific active agent may have more than one activity, function or effect.
Suitable active agents for use in the vehicles and formulations described herein alone or in conjunction with imiquimod include, but are not limited to, active herbal extracts, acaricides, age spot and keratose removing agents, allergen, analgesics, local anesthetics, antiacne agents, antiallergic agents, antiaging agents, antibacterials, antibiotics, antiburn agents, anticancer agents, antidandruff agents, antidepressants, antidermatitis agents, antiedemics, antihistamines, antihelminths, antihyperkeratolyte agents, antiinflammatory agents, antiirritants, antilipemics, antimicrobials, antimycotics, antiproliferative agents, antioxidants, anti-wrinkle agents, antipruritics, antipsoriatic agents, antirosacea agents antiseborrheic agents, antiseptic, antiswelling agents, antiviral agents, antiyeast agents, astringents, topical cardiovascular agents, chemotherapeutic agents, corticosteroids, dicarboxylic acids, disinfectants, fungicides, hair growth regulators, hormones, hydroxy acids, interferons, immunosuppressants, immunoregulating agents, insecticides, insect repellents, keratolytic agents, lactams, metals, metal oxides, mitocides, neuropeptides, steroids, non-steroidal anti-inflammatory agents, oxidizing agents, pediculicides, photodynamic therapy agents, retinoids, sanatives, scabicides, self tanning agents, skin whitening agents, vasoconstrictors, vasodilators, vitamins, vitamin D derivatives, wound healing agents and wart removers as well as agents having activity against superficial basal cell carcinomas, actinic keratoses, Bowen's disease and or other squamous cell carcinomas and molluscum contagiosum. As is known to one skilled in the art, in some instances a specific active agent may have more than one activity, function or effect.
In one or more embodiments, the formulation includes a steroidal anti-inflammatory agent. In an embodiment the wax, waxy substance, counterpart or derivative thereof is present in the composition in an amount sufficient to solubilize the steroid. Exemplary steroidal anti-inflammatory agents include, but are not limited to, corticosteroids such as hydrocortisone, hydroxyltriamcinolone, alpha-methyl dexamethasone, dexamethasone-phosphate, beclomethsone dipropionate, clobetasol valemate, desonide, desoxymethasone, desoxycorticosterone acetate, dexamethasone, dichlorisone, diflorasone diacetate, diflucortolone valerate, fluadrenolone, fluclorolone acetonide, fludrocortisone, flumethasone pivalate, fluosinolone acetonide, fluocinonide, flucortine butylester, fluocortolone, fluprednidene (fluprednylidene) acetate, flurandrenolone, halcinonide, hydrocortisone acetate, hydrocortisone butyrate, methylprednisolone, triamcinolone acetonide, cortisone, cortodoxone, flucetonide, fludrocortisone, difluorosone diacetate, fluradrenolone acetonide, medrysone, amcinafel, amcinafide, betamethasone and the balance of its esters, chloroprednisone, chlorprednisone acetate, clocortelone, clescinolone, dichlorisone, difluprednate, flucloronide, flunisolide, fluoromethalone, fluperolone, fluprednisolone, hydrocortisone valerate, hydrocortisone cyclopentylpropionate, hydrocortmate, mepreddisone, paramethasone, prednisolone, prednisone, beclomethasone dipropionate, triamcinolone, and mixtures thereof.
In one embodiment, the formulation includes an immunomodulator. In an embodiment the wax, waxy substance, counterpart or derivative thereof is present in the composition in an amount sufficient to solubilize the immunomodulator. Immunomodulators are chemically or biologically-derived agents that modify the immune response or the functioning of the immune system (as by the stimulation of antibody formation or the inhibition of white blood cell activity). Immunomodulators include, among other options, cyclic peptides, such as cyclosporine, tacrolimus, tresperimus, pimecrolimus, sirolimus (rapamycin), verolimus, laflunimus, laquinimod and imiquimod. Such compounds, delivered in the foam, are especially advantageous in skin disorders such as psoriasis, eczema and atopic dermatitis, where the large skin areas are to be treated.
In one embodiment, the formulation includes an interferon. In an embodiment the wax, waxy substance, counterpart or derivative thereof is present in the composition in an amount sufficient to solubilize the interferon.
In one embodiment, the formulation includes an podophyllin (anti-mitotic), In an embodiment the wax, waxy substance, counterpart or derivative thereof is present in the composition in an amount sufficient to solubilize the podophyllin (anti-mitotic).
In one embodiment, the formulation includes a podofilox. In an embodiment the wax, waxy substance, counterpart or derivative thereof is present in the composition in an amount sufficient to solubilize the podofilox.
In one embodiment, the formulation includes a 5-fluorouracil (5-FU). In an embodiment the wax, waxy substance, counterpart or derivative thereof is present in the composition in an amount sufficient to solubilize the 5-fluorouracil (5-FU).
In an embodiment, the active agent is selected from at least one of imiquimod, an interferon, an immunomodulator, podophyllin (anti-mitotic), podofilox, 5-fluorouracil (5-FU), and trichloroacetic acid (TCA).
In an embodiment, the active agent is selected from at least one of Fluorouracil, afovirsen, inosine pranobex, podophyllum, trichloroacetic acid, thiotep, diclofenac, 5-aminolevulinic acid and derivatives, and tretinoin.
In one or more embodiments imiquimod is used in combination with meglumine antimoniate (for cutaneous leishmaniasis); cryotherapy [liquid nitrogen] (for plantal and periungual warts/actinic keratoses); acyclovir (genital hsv-2 infection); 5-aminolevulinic acid (for genital bowenoid papulosis); fluorouracil (anal and perianal squamous cell carcinoma; salicylic acid (anal and genital warts); a COX inhibitor sulindac (for squamous cell carcinoma).
In one or more embodiments the composition does not contain a basic active agent. In one or more embodiments the composition does not contain an acidic active agent. In other embodiments the composition does not contain a neutralizing active agent. In further embodiments the composition is not partially neutralized by the active agent. In alternative embodiments the active agent may be basic. In still further alternative embodiments the active agent may be acidic. In one or more embodiments the active agent is dissolved in the liquid wax. In one or more preferred embodiments the liquid wax is a fatty acid. In one or more further embodiments the solubilizing power of the liquid wax is boosted by the addition of an organic acid in combination with fatty acid. In other embodiments the solubilizing power of the liquid wax is boosted by the addition of an organic acid in combination with fatty acid and fatty alcohol. Solubilization may also be helped by the presence of an organic hydrophobic solvent such as capric/caprylic triglycerides. In a preferred embodiment the organic acid is a hydroxy acid. Non limiting examples of alpha hydroxy acids are glycolic, lactic, citric, malic and tartaric acid. Beta hydroxy acids include salicylic acid, beta-hydroxybutyric acid, beta-hydroxy beta-methylbutyrate, carnitine, tropic acid trethocanic acid and 3-Hydroxypropionic acid. In a preferred embodiment the hydroxy acids are liquid. In another embodiment the organic acid is a sugar acid including aldonic, uronic and aldaric acids. Particular examples of sugar acids are ascorbic and glucoronic acids. Included are the corresponding salts and pharmaceutically-acceptable derivatives; or any combination of any of the foregoing.
Because of the multiple therapeutic properties of waxes, waxy substances, counterparts and derivatives thereof the combination of such waxes, waxy substances, counterparts and derivatives thereof with imiquimod or another active agents can result in a synergistic therapeutic benefit.
Encapsulation of an Active Agent
In one or more embodiments, the active agent is encapsulated in particles, microparticles, nanoparticles, microcapsules, microspheres, nanocapsules, nanospheres, liposomes, niosomes, polymer matrix, silica-gel, graphite, nanocrystals or microsponges. Such particles can have various functions, such as (1) protection of the active agent from degradation; (2) modification of the active agent release rate from the composition; (3) control of skin penetration profile; and (4) mitigation of adverse effects, due to the controlled release of the active agent from the encapsulation particles.
For example, in one embodiment, the active agent is imiquimod. Imiquimod is difficult to solubilize. For example large amounts of liquid fatty acid isostearic acid are required to solubilize the active agent. Therefore in certain embodiments imiquimod is encapsulated in particles, microparticles, nanoparticles, microcapsules, microspheres, nanocapsules, nanospheres, liposomes, niosomes, polymer matrix, silica-gel, graphite, nanocrystals or microsponges. Such particles can have various functions, such as (1) protection of the imiquimod from degradation; (2) modification of the imiquimod release rate from the composition; (3) control of skin penetration profile; and (4) mitigation of adverse effects, due to the controlled release of the imiquimod from the encapsulation particles.
“Microsponges” are rigid, porous and spongelike round microscopic particles of cross-linked polymer macroporous beads (e.g., polystyrene, copolymers thereof; methyl methacrylate/glycol dimethacrylate crosspolymer), each defining a substantially noncollapsible pore network. Microsponges have a size range in between 5 to 300 μm (typically 10-25 microns) in diameter. The Microsponges can be loaded with an active ingredient and can provide enhanced control, spreadability, safety, stability and improved aesthetic properties including controlled time release of the active ingredient to skin or to a mucosal membrane upon application of the formulation. Release is triggered, for example, by application to the skin surface such as through rubbing and or higher than-ambient skin temperature. The slow release is intended to reduce irritation by the active. Microsponge® delivery technology was developed by Advanced Polymer Systems. Examples of drugs that have been incorporated in microsponges include ibuprofen ketoprofen (non-steroidal anti-inflammatory agent), benzyl peroxide (an anti-acne agent), retinoids, such as retinoic acid and retinol, fluconazole (an antifungal agent). They can also reduce perceived oiliness. Microsponges, when applied to the skin, release the active agent on a time mode and also in response to other stimuli (rubbing, temperature, pH, etc). By delivering the active gradually to the skin, microsponge-benzoyl peroxide formulations, for example, have excellent efficacy with minimal irritation. Microsponges collect on the skin or mucosal surface and slowly release the entrapped agent. The empty spheres are washed away with cleansing.
Microsponges may be incorporated in wide ranges of foam formulations. In one or more embodiments microsponges may be incorporated into the formulations exemplified and described herein. In an embodiment the amount of microsponges may be varied from about 1% to about 25% of the formulation. In some embodiments they are from about 3% to about 15%. In other embodiments they are from about 5% to about 15%. In an embodiment any active agent suitable for loading in microsponges may be used. In specific embodiments active agents such as benzyl peroxide (BPO), tretinoin, hydroquinone, ketoprofen, retinol, fluconazole, ibuprofen, trolamine, a vitamin, imiquimod and the like may be used. As can be noted from above and herein different types of active agents may be loaded into the microsponges. Accordingly, the foam formulation selected in which to disperse the microsponges should be adapted so that the active agent remains substantially entrapped in the microsponges. In certain embodiments the active agent is present both in the foam formulation and in the microsponges so that some of the active agent is available for immediate penetration on application of the foam and that other amounts of active agent are provided by slow or controlled release from the microsponges now sitting on the topical surface. In an embodiment where the active ingredient is insoluble in water and is entrapped in the microsponges there is provided true wax in water emulsion, where the active ingredient is only exposed to the external water phase and does not access the internal wax phase. In an embodiment the foam formulation includes a large amount of hydrophobic surfactant which can form a tight close surfactant layer surrounding the wax droplets sitting in the water phase to separate but still holding the water and wax phases together as an emulsion, thereby preventing or at least substantially reducing any leakage of active agent into the wax phase.
Fields of Applications
The foamable carrier is suitable for treating any inflicted surface. In one or more embodiments, foamable carrier is suitable for administration to the skin, a body surface, a body cavity or mucosal surface, e.g., the cavity and/or the mucosa of the nose, mouth, eye, ear, respiratory system, vagina or rectum (severally and interchangeably termed herein “target site”).
In one embodiment, the disorder is a dermatological disorder, which can be treated by an active agent or can prevent or ameliorate the disorder. In another embodiment the disorder is a mucosal disorder.
In another embodiment, the disorder is a dermatological disorder that benefits from the use of imiquimod in conjunction with another active agent. The wax, waxy substance, counterpart or derivative thereof may be of benefit by improving the solubility of the active agent or increasing the penetration of the active agent. The wax, waxy substance, counterpart or derivative thereof may also provide a synergistic therapeutic effect in combination with the active agent.
By selecting a suitable active agent, or a combination of two or more active agents, the foamable composition is useful in treating an animal or a human patient having any one of a variety of dermatological disorders, including dermatological pain, dermatological inflammation, acne, acne vulgaris, inflammatory acne, non-inflammatory acne, acne fulminans, nodular papulopustular acne, acne conglobata, dermatitis, bacterial skin infections, fungal skin infections, viral skin infections, parasitic skin infections, skin neoplasia, skin neoplasms, pruritis, cellulitis, acute lymphangitis, lymphadenitis, erysipelas, cutaneous abscesses, necrotizing subcutaneous infections, scalded skin syndrome, folliculitis, furuncles, hidradenitis suppurativa, carbuncles, paronychial infections, rashes, erythrasma, impetigo, eethyma, yeast skin infections, warts, molluscum contagiosum, trauma or injury to the skin, post-operative or post-surgical skin conditions, scabies, pediculosis, creeping eruption, eczemas, psoriasis, pityriasis rosea, lichen planus, pityriasis rubra pilaris, edematous, erythema multiforme, erythema nodosum, granuloma annulare, epidermal necrolysis, sunburn, photosensitivity, pemphigus, bullous pemphigoid, dermatitis herpetiformis, keratosis pilaris, callouses, corns, ichthyosis, skin ulcers, ischemic necrosis, miliaria, hyperhidrosis, moles, Kaposi's sarcoma, melanoma, malignant melanoma, basal cell carcinoma, squamous cell carcinoma, poison ivy, poison oak, contact dermatitis, atopic dermatitis, rosacea, purpura, moniliasis, candidiasis, baldness, alopecia, Behcet's syndrome, cholesteatoma, Dercum disease, ectodermal dysplasia, gustatory sweating, nail patella syndrome, lupus, hives, hair loss, Hailey-Hailey disease, chemical or thermal skin burns, scleroderma, aging skin, wrinkles, sun spots, necrotizing fasciitis, necrotizing myositis, gangrene, scarring, and vitiligo.
Likewise, the foamable composition is suitable for treating a disorder of a body cavity or mucosal surface, e.g., the mucosa of the nose, mouth, eye, ear, respiratory system, vagina or rectum. Non limiting examples of such conditions include chlamydia infection, gonorrhea infection, hepatitis B, herpes, HIV/AIDS, human papillomavirus (HPV), genital warts, bacterial vaginosis, candidiasis, chancroid, granuloma Inguinale, lymphogranuloma venereum, mucopurulent cervicitis (MPC), molluscum contagiosum, nongonococcal urethritis (NGU), trichomoniasis, vulvar disorders, vulvodynia, vulvar pain, yeast infection, vulvar dystrophy, vulvar intraepithelial neoplasia (VIN), contact dermatitis, pelvic inflammation, endometritis, salpingitis, oophoritis, genital cancer, cancer of the cervix, cancer of the vulva, cancer of the vagina, vaginal dryness, dyspareunia, anal and rectal disease, anal abscess/fistula, anal cancer, anal fissure, anal warts, Crohn's disease, hemorrhoids, anal itch, pruritus ani, fecal incontinence, constipation, polyps of the colon and rectum.
In an embodiment, the disorder is a dermatological disorder, which can be treated, ameliorated or prevented by a wax, waxy substance, counterpart, or derivative thereof.
In an embodiment, the disorder is a dermatological disorder, which can be treated, ameliorated or prevented by at least one of imiquimod, an interferon, an immunomodulator, podophyllin (anti-mitotic), podofilox, 5-fluorouracil (5-FU), and trichloroacetic acid (TCA).
In an embodiment, the disorder is a dermatological disorder, which can be treated by a topical steroid.
In an embodiment, the disorder is a dermatological disorder, which can be treated by an immunomodulator.
In an embodiment, the disorder is a dermatological disorder, which can be treated by an anti-infective agent, such as an antibacterial agent, and antibiotic, an antifungal agent and an antiviral agent.
In an embodiment, the disorder is a dermatological disorder, which is common in children. Foam is advantageous in the topical treatment of children, who are sensitive to treatment with a cream or ointment.
In an embodiment, the disorder is atopic dermatitis and the active agent is a steroid.
In an embodiment, the disorder is psoriasis and the active agent is a steroid, optionally further including a DCA or DCA ester to stabilize or solubilize the topical steroid.
In an embodiment, the disorder is selected from psoriasis and atopic dermatitis and the active agent comprises a steroid and an additional non-steroidal active agent, such as a vitamin D derivative, optionally further including a DCA or DCA ester to stabilize or solubilize the topical steroid and/or non-steroidal active agent.
In an embodiment, the disorder is selected from psoriasis and atopic dermatitis and the active agent comprises an immunomodulator, optionally further including a DCA or DCA ester to stabilize or solubilize the immunomodulator.
In an embodiment, the composition is useful for the treatment of an infection. In one or more embodiments, the composition is suitable for the treatment of an infection, selected from the group of a bacterial infection, a fungal infection, a yeast infection, a viral infection and a parasitic infection.
In an embodiment, the composition is useful for the treatment of wound, ulcer and burn.
The composition is also suitable for administering a hormone to the skin or to a mucosal membrane or to a body cavity, in order to deliver the hormone into the tissue of the target organ, in any disorder that responds to treatment with a hormone.
Other foamable compositions and components for foamable compositions are described in: U.S. Publication No. 05-0232869, published on Oct. 20, 2005, entitled NONSTEROIDAL IMMUNOMODULATING KIT AND COMPOSITION AND USES THEREOF; U.S. Publication No. 05-0205086, published on Sep. 22, 2005, entitled RETINOID IMMUNOMODULATING KIT AND COMPOSITION AND USES THEREOF; U.S. Publication No. 06-0018937, published on Jan. 26, 2006, entitled STEROID KIT AND FOAMABLE COMPOSITION AND USES THEREOF; U.S. Publication No. 05-0271596, published on Dec. 8, 2005, entitled VASOACTIVE KIT AND COMPOSITION AND USES THEREOF; U.S. Publication No. 06-0269485, published on Nov. 30, 2006, entitled ANTIBIOTIC KIT AND COMPOSITION AND USES THEREOF; U.S. Publication No. 07-0020304, published on Jan. 25, 2007, entitled NON-FLAMMABLE INSECTICIDE COMPOSITION AND USES THEREOF; U.S. Publication No. 06-0193789, published on Aug. 31, 2006, entitled FILM FORMING FOAMABLE COMPOSITION; U.S. patent application Ser. No. 11/732,547, filed on Apr. 4, 2007, entitled ANTI-INFECTION AUGMENTATION OF FOAMABLE COMPOSITIONS AND KIT AND USES THEREOF; U.S. Provisional Patent Application No. 60/789,186, filed on Apr. 4, 2006, KERATOLYTIC ANTIFUNGAL FOAM; U.S. Provisional Patent Application No. 0/815,948, filed on Jun. 23, 2006, entitled FOAMABLE COMPOSITIONS COMPRISING A CALCIUM CHANNEL BLOCKER, A CHOLINERGIC AGENT AND A NITRIC OXIDE DONOR; U.S. Provisional Patent Application No. 60/818,634, filed on Jul. 5, 2006, entitled DICARBOXYLIC ACID FOAMABLE VEHICLE AND PHARMACEUTICAL COMPOSITIONS THEREOF; U.S. Provisional Patent Application No. 60/843,140, filed on Sep. 8, 2006, entitled FOAMABLE VEHICLE AND VITAMIN PHARMACEUTICAL COMPOSITIONS THEREOF, all of which are incorporated herein by reference in their entirety. More particularly any of the active ingredients; the solvents; the surfactants; foam adjuvants; penetration enhancers; humectants; moisturizers; and other excipients as well as the propellants listed therein can be applied herein and are incorporated by reference.
The following examples further exemplify the benefits provided by foamable pharmaceutical carriers described in the present application, as well as the benefits of pharmaceutical compositions thereof, methods for preparing the same, and therapeutic uses of the compositions. The examples are for the purposes of illustration only and are not intended to be limiting. Many variations may be carried out by one of ordinary skill in the art and are contemplated within the full scope.
Methodology
A general procedure for preparing foamable compositions is set out in WO 2004/037225, which is incorporated herein by reference.
Emulsion Foam


    
    
        1. Mix oily phase ingredients and heat to 75° C. to melt all ingredients and obtain homogeneous mixture.
        2. Mix polymers, if any, in water with heating or cooling as appropriate for specific polymer. Whilst the polymers may be added instead into the oily phase it was found to be advantageous to prepare them in the water phase.
        3. Add all other water soluble ingredients to water-polymer solution and heat to 75° C.
        4. Add slowly internal phase to external phase at 75° C. under vigorous mixing and homogenize to obtain fine emulsion. Alternatively the external phase is added slowly to the internal phase.
        5. Cool to below 40° C. and add sensitive ingredients with mild mixing.
        6. Cool to room temperature.
    
    


The above methodology may be used for the wax emulsion formulations. Reasonable changes or variations to the methodology may be introduced as will be appreciated by someone of the art to fit a specific formulation. Specific non limiting examples appear in the Examples section below.
The methodology of loading microsponges with active agent and amounts that can be loaded are described in WO 01/85102, which is incorporated herein by way of reference.
Canisters, Filling and Crimping
The canisters are then filled with the formula prior to addition of propellant, sealed and crimped with a valve and pressurized with the propellant. A nonlimiting exemplary procedure includes the following steps:

    
    
        1. Each aerosol canister 35×70 mm is filled with 30±5% g of the composition;
        2. Each canister is closed with an aerosol valve, using a vacuum crimping machine;
        3. Propellant (e.g., mix of propane, butane and isobutane) is added to each of the canisters. Canisters are then warmed for about 30 sec in a warm bath at about 50° C. and well shaken immediately thereafter.

Closure Integrity Test.

    
    


Each pressurized canister can be subjected to bubble and crimping integrity testing by immersing the canister in a 60° C. water bath for 2 minutes. Canisters are observed for leakage as determined by the generation of bubbles. Canisters releasing bubbles are rejected.
Production Under Vacuum
Optionally, the foamable formulation may be produced under nitrogen and under vacuum. Whilst the whole process can be carried out under an oxygen free environment, it can be sufficient to apply a vacuum after heating and mixing all the ingredients to obtain an emulsion or homogenous liquid. Preferably the production chamber is equipped to apply a vacuum but if not the formulation can be for example placed in a dessicator to remove oxygen prior to filing and crimping.
Tests
By way of non limiting example the objectives of hardness, collapse time and FTC stability tests are briefly set out below as would be appreciated by a person of the art.
Hardness
LFRA100 instrument is used to characterize hardness. A probe is inserted into the test material. The resistance of the material to compression is measured by a calibrated load cell and reported in units of grams on the texture analyzer instrument display. Preferably at least three repeat tests are made. The textural characteristics of a dispensed foam can effect the degree of dermal penetration, efficacy, spreadability and acceptability to the user. The results can also be looked at as an indicator of softness. Note: the foam sample is dispensed into an aluminum sample holder and filled to the top of the holder.
Collapse Time
Collapse time (CT) is examined by dispensing a given quantity of foam and photographing sequentially its appearance with time during incubation at 36° C. It is useful for evaluating foam products, which maintain structural stability at skin temperature for at least 1 min. Foams which are structurally stable on the skin for at least one minute are termed “short term stable” compositions or foams.
Viscosity
Viscosity is measured with Brookfield LVDV-II+PRO with spindle SC4-25 at ambient temperature and 10, 5 and 1 RPM. Viscosity is usually measured at 10 RPM. However, at about the apparent upper limit for the spindle of  ̃>50,000 CP, the viscosity at 1 RPM may be measured, although the figures are of a higher magnitude.
FTC (Freeze Thaw Cycles)
To check the foam appearance under extreme conditions of repeated cycles of cooling, heating, (first cycle) cooling, heating (second cycle) etc., commencing with −10° C. (24 hours) followed by +40° C. (24 hours) measuring the appearance and again repeating the cycle for up to three times.
Microscopic Examination
The procedure used for evaluating the compositions by microscope examination is as follows:

    
    
        1) A homogenous formulation or foam produced from a homogenous formulation is taken and a representative sample drop of foam or pre foamed formulation as appropriate is taken and placed on a glass slide using a capillary tube.
        2) The drop is carefully covered with a deck glass cover slide
        3) The sample is placed under a light microscope (Nikon eclipse 50i) for observation, using a polarizer at a magnification of ×200. Multiple points over the area of the sample are checked.
        4) The presence or absence of crystals is noted.
        5) If no crystals are observed visually in the sample the formulation is considered to be substantially free of crystals. However, this term does not exclude the possibility of crystals being observed at a higher magnification or occasionally in other samples
    
    


Sensation
Healthy volunteers selected at random were give a sample of foam formulation and applied it to the skin on their hand or forearm and were asked for their observations.
Bubble Size
Foams are made of gas bubbles entrapped in liquid. The bubble size and distribution reflects in the visual texture and smoothness of the foam. Foam bubble size is determined by dispensing a foam sample on a glass slide, taking a picture of the foam surface with a digital camera equipped with a macro lens. The diameter of about 30 bubbles is measured manually relatively to calibration standard template. Statistical parameters such as mean bubble diameter, standard deviation and quartiles are then determined. Measuring diameter may also be undertaken with image analysis software. The camera used was a Nikon D40X Camera (resolution 10 MP) equipped with Sigma Macro Lens (ref: APO MACRO 150 mm F2.8 EX DG HSM). Pictures obtained are cropped to keep a squared region of 400 pixels×400 pixels. The light microscope enables observing and measuring particles from about a few millimeters down to about one micron. Light microscope is limited by the visible light wavelength and therefore is useful to measuring size of particles above 800 nanometers and practically from 1 micron (1,000 nanometers).
Shakability
“Shakability” represents the degree to which the user is able to feel/hear the presence of the liquid contents when the filled pressurized canister is shaken. Shaking is with normal mild force without vigorous shaking or excessive force. When the user cannot sense the motion of the contents during shaking the product may be considered to be non shakable. This property may be of particular importance in cases where shaking is required for affecting proper dispersion of the contents.
Shakability Scoring:













Good shakability (conforms to required quality specification)
2


Moderate shakability (conforms to required quality specification)
1


Not or hardly shakable but may still be flowable and allow foam
0


formation of quality


Is substantially not able to pass through valve
Block









Aging or Creaming by Centrifugation
Aging or creaming was evaluated by centrifugation, as described below:
1. Principle of Test


    
    
        The centrifugation used in this procedure serves as a stress condition simulating the aging of the liquid dispersion under investigation. Under these conditions, the centrifugal force applied facilitates the coalescence of dispersed globules or sedimentation of dispersed solids, resulting in loss of the desired properties of the formulated dispersion. The presence of some creaming at the enormous centrifugal forces imposed on the formulations does not derogate from the fact that the compositions have not phase separated and can still be understood as being resistant to creaming and provides a good indication of the long term stability of the formulations. To the extent that good quality stable formulations are achieved, which are resistant to creaming or such that no creaming is observed, the formulations are considered as exceptionally stable. The procedure is as follows:
        1.1. Following preparation of the experimental formulation/s, allow to stand at room temperature for ≧24 h.
        1.2. Handle pentane in the chemical hood. Add to each experimental formulation in a 20-mL glass vial a quantity of pentane equivalent to the specified quantity of propellant for that formulation, mix and allow formulation to stand for at least 1 h and not more than 24 h.
        1.3. Transfer each mixture to 1.5 mL microtubes. Tap each microtube on the table surface to remove entrapped air bubbles.
        1.4. Place visually balanced microtubes in the centrifuge rotor and operate the centrifuge at about 300 rpm for 10 min. about 1,000 rpm for 10 min. or at about 3,000 rpm for 10 min or at about 10,000 rpm for 10 min. The centrifuge can be a BHG HEMLE Z 231 M.
        1.5. Centrifugation can also be executed at a higher rpm for a shorter period or a lower rpm for a longer period bearing in mind the G force experienced by the formulations is many fold greater than the one G to which a formulation would be exposed to during its shelf life.
    
    


Intra-Canister Uniformity
Representative product containers are collected, sample test solutions are prepared and the content of the analyte is determined according to standard methods in the art. Variability of content is characterized as percent difference or relative standard deviation, as appropriate, according to the number of samples evaluated.
The results ascertain variability or uniformity within a given container in content of analytes (primarily active pharmaceutical ingredients, but also preservatives) taken from different parts of a pressurized canister drug products
Two full canisters were shaken according to product instructions. About 1-3 g of Foam was dispensed from each canister and discarded. Foam sufficient for two replicate sample solution preparations was then dispensed into a glass beaker. This represents the initial sample. A middle portion is then dispensed from each canister being about half the canister contents. This middle dispensed portion may be discarded or collected for testing purposes, as necessary. Foam sufficient for two replicate sample solution preparations was then dispensed into a glass beaker. This represents the final sample. A small amount of formulation remains in the canister. The foam samples were stirred to remove gas/air bubbles. From both the initial and final foam portions from each canister 4 separate sample solutions are prepared and analyzed, 2 from the initial portion and 2 from the final portion. The percent difference is calculated as follows:




  
    
      
        
          
            
              
                Difference
                ⁢
                
                  
                
                ⁢
                between
                ⁢
                
                  
                
                ⁢
                content
                ⁢
                
                  
                
                ⁢
                determined
                ⁢
                
                  
                
                ⁢
                in
                ⁢
                
                  
                
                ⁢
                initial
              
              ⁢
              
                
              
              &
            
          
        
        
          
            
              final
              ⁢
              
                
              
              ⁢
              portions
            
          
        
      
      ⁢
      
        
      
    
    
      
        
          Mean
          ⁢
          
            
          
          ⁢
          of
          ⁢
          
            
          
          ⁢
          content
          ⁢
          
            
          
          ⁢
          of
          ⁢
          
            
          
          ⁢
          initial
        
        ⁢
        
          
        
        &
      
      ⁢
      
        
      
      ⁢
      final
      ⁢
      
        
      
      ⁢
      portions
    
  
  ×
  100




and the intra canister uniformity evaluated from the results.
Stock Compositions
Non-limiting examples of how stock solutions are made up with and without API. Other stock solutions may be made using the same methodology by simply varying adding or omitting ingredients as would be appreciated by one of the ordinary skills in the art.
EXAMPLES
The invention is described with reference to the following examples. This invention is not limited to these examples and experiments. Many variations will suggest themselves and are within the full intended scope of the appended claims.
Section A—Aqueous Liquid Wax Formulations
A1—Example 1—Vehicle Composition Containing Isostearic Acid
The following foamable vehicles were prepared and the quality of the resultant foam was ascertained.

















036
007
010
032
040





















Ingredients







Isostearic acid
20
30
50
60
60


Pemulen TR-2
0.62
0.4
0.4
0.3
—


Polysorbate 80
3
3
3
3
3


Purified water
76.38
66.6
46.6
36.7
37


Total:
100
100
100
100
100


Propellant
8
8
8
8
8


AP70


Results


PFF (pre foam


formulation)


Centrifugation
30% cr.
80% cr
90% cr
stable
60% cr.


3K
10% sep.


Centrifugation



50% cr.


10K


Microscopic
No
No
No
No
Yes


Observation
Crystals
Crystals
Crystals
Crystals
Crystals


Foam


Appearance
E
E
E−
G
E


Color
White
White
White
White
white


Odor
1
very faint
very faint
1
1




odor
odor


Shakability
G = Good
Good
Good
Good
Good


Density (g/mL)
0.045
n/a
n/a
0.063
0.045


Microscopic
No
No
No
No
Yes


Observation
Crystals
Crystals
Crystals
Crystals
Crystals


Collapse time
>300/FG
>300/G
>300/FG
>300/FG


36° C. (sec)


Foam pH
3.93
n/a
n/a
4.08


(diluted 1:5)









Compositions contain 20%, 30%, 50%, 60%, isostearic acid to provide; (1) solubilizing capacity; and (2) potentially enhanced skin delivery of an active agent and (3) some emolliency and or (4) some substantially organized chaos by virtue of its non linear shape enabling both shakability and flowability of the wax formulation and potentially enhanced skin penetration.
The compositions contain from about 66% to about 37% water. Therefore, they can provide a good skin feeling effect even at high concentrations.
Up to about 60% isostearic acid the compositions are believed to be wax in water emulsions. The 60% formulation was examined by water addition test was found to be liquid wax in water emulsion despite the fact that the amount of liquid wax phase was approximately double that of the aqueous phase. Liquid wax in water emulsion is maintained and stabilized by selecting a surfactant that favors liquid wax in water emulsions over water in liquid wax emulsions. Hence, the skin feeling of the composition is favorable.
At about 70% isostearic acid there is significant tension to form a water in liquid wax emulsion. Using 0.4% permulen with 3% polysorbate 80, which favours a liquid wax in water emulsion, did not release foam at these levels of isostearic acid. Reducing the permulen to half resulted in a poor foam. By using PEG 30 dipolyhydroxysearate (Arlacel P-135) it is possible to form a water in liquid wax emulsion, however it produced a poor foam with or without polymer. It is predicted though, (based on 70% oleyl alcohol foam exemplified below in Example 3), that at about 70% isostearic acid with polysorbate 80 as surfactant and no polymer, a foam of quality can still be produced.
Without being bound to any particular theory the physical change in the formulation may be due to isostearic acid reaching a concentration where phase reversal from wax in water to water in wax emulsion is possible. Also at this concentration range of isostearic acid removal of the polymeric agent, which itself can absorb water may—without being bound by any theory—perhaps reduce internal emulsion tensions resulting from the presence of the thickening polymeric agent and thereby unexpectedly resulting in improved foam quality even though polymeric agents are normally added to strengthen foam quality. Also as the concentration of isostearic acid increased and consequently the amount of water decreased it may be that the amount of surfactant required can be reduced as the external water phase is thinner.
It further appears to be the case that—without being limited by any theory—for any given emulsion system as the liquid wax phase is increased with a corresponding decrease in the water phase the internal tension or pressure for phase reversal will increase and the point at which the phase reversal can occur can be retarded by selective use of non traditional derivatized polymeric agents with emulsifying properties, such as permulen that can stabilize the formulation and help improve resistance to creaming they may in small amounts be able to push back the point at which pressure for phase reversal might otherwise occur but subject to the caveat that whilst removal of polymer may improve visual foam appearance it can result in a lesser resistance to creaming. By fine tuning of the formulations and or addition of other stabilising substances as can be seen in Examples 2, 3, 4 and Example 8 the resistance to creaming can be improved.
A foam of quality was not achieved with only permulen and isostearic acid.
These compositions can be used as a vehicle for pharmaceutical and cosmetic agents especially those soluble in liquid waxes or water. For example imiquimod is soluble in isostearic acid.
In order to create a foamable composition, the composition is filled into an aerosol canister and pressurized using a liquefied or gas propellant can be added at a concentration of about 3% to about 25%.
A1—Example 2—Vehicle Composition Containing Isostearic Acid, Oleyl Alcohol and Active Agent
The following foamable pharmaceutical compositions were prepared and the quality of the resultant foam was ascertained.














002
003


















Ingredients




Isostearic acid
30
30


Caprilic/capric triglycerides
2.5
2.5


Oleyl alcohol
7.5
7.5


Sorbitan Stearate
0.65
0.65


Imiquimod
5
5


Benzyl alcohol
2
2


Xanthan gum
0.35
—


Hydroxypropyl methylcellulose
0.35
—


Glycerin
2
2


Polysorbate 60
2.5
2.5


Methyl hydroxybenzoate
0.2
0.2


Propyl hydroxybenzoate
0.02
0.02


Purified water
46.93
47.63


Total:
100
100


Propellant AP70
8
8


Results


PFF (pre foam formulation)


Centrifugation 3K
stable
55


Viscosity (cPs)
12806
18.2


Microscopic Observation
No Crystals
No Crystals


Foam


Visual inspection
Homogeneous
Homogeneous


(pressurized glass bottle)


Appearance
G
G


Color
White
White


Odor
very faint odor
very faint odor


Shakability
moderate
Good


Density (g/mL)
0.051
0.039


Microscopic Observation
No Crystals
No Crystals


Collapse time 36° C. (sec)
>300/FG
>300/FG









These compositions contain 30% isostearic acid and 7.5% oleyl alcohol and 2.5% capric caprylic triglycerides to provide (1) emolliency; (2) solubilizing capacity; and (3) potentially enhanced skin delivery of an active agent and or (4) some organized chaos by virtue of the non linear shape of the liquid waxes enabling both shakability and flowability of the wax formulation and potentially enhanced skin penetration.
Formulation 02 was found to be stable to centrifugation at 3000 rpm for 10 minutes indicating that it should be substantially resistant to aging and physically shelf stable.
The compositions contain about 47% water. Therefore, they provide a good skin feeling effect.
The compositions are oil in water emulsions. Hence, the skin feeling of the composition is favorable.
The compositions can be used for topical therapy of a skin disorder treatable by imiquimod, which can include treating, containing, ameliorating or preventing actinic keratosis, superficial basal cell carcinoma and external genital warts.
These compositions can be used as a vehicle for other pharmaceutical and cosmetic agents especially those soluble in liquid waxes or water.
In order to create a foamable composition, the composition is filled into an aerosol canister and pressurized using a liquefied or gas propellant can be added at a concentration of about 3% to about 25%.
A2—Example 3—Vehicle Composition Containing Oleyl Alcohol
The following foamable vehicles were prepared and the quality of the resultant foam was ascertained.
(a) Oleyl alcohol alone from 20% to 70%

















Ingredients
037
006
009
015
031
039
044






















Oleyl alcohol
20
30
50
60
60
60
70


Pemulen TR-2
0.62
0.4
0.4
0.4
0.3
—
—


Polysorbate 80
3
3
3
3
3
3
3


Purified water
76.38
66.6
46.6
36.6
36.7
37
27


Total:
100
100
100
100
100
100
100


Propellant
8
8
8
8
8
8
8


AP70







Results PFF (pre foam formulation)














Centrifugation
20% cr.
80% cr
90% cr
—
stable
60% cr.
60% cr.


3K
20% sep.


Centrifugation



—
50% cr.


10K


Microscopic
No
No
No
—
No
No
No


Observation
Crystals
Crystals
Crystals

Crystals
Crystals
Crystals


Foam



—


Appearance
E =
E
E
FG =
G =
G
G+



excellent


fairly
Good






good


Color
White
White
White
—
White
white
white


Odor
1
very faint
very faint
—
1
1
1




odor
odor


Shakability
Good
Good
Good
—
Good
Good
Good


Density (g/mL)
0.045
n/a
n/a
—
0.062
0.041
0.059


Microscopic
No
No
No
—
No
No
No


Observation
Crystals
Crystals
Crystals

Crystals
Crystals
Crystals


Collapse time
>300/FG
>300/FG
>300/FG
—


36° C. (sec)


Foam pH
3.89



4.16


(diluted 1:5)









The compositions contain 20%, 30%, 50%, 60%, and 70% oleyl alcohol to provide: (1) solubilizing capacity; and (2) potentially enhanced skin delivery of an active agent and (3) some emolliency and/or (4) some substantially organized chaos by virtue of its non linear shape enabling both shakability and flowability of the wax formulation and potentially enhanced skin penetration.
The compositions contain from about 66% to about 27% water. Therefore, they can provide a good skin feeling effect even at high concentrations.
Up to about 70% oleyl alcohol the compositions are believed to be wax in water emulsions, The 60% and 70% formulations were examined by water addition test and were found to be liquid wax in water emulsions despite the fact that the amount of liquid wax phase was approximately more than double that of the aqueous phase. Liquid wax in water emulsion is maintained and stabilized by selecting a surfactant that favors liquid wax in water emulsions over water in liquid wax emulsions. Preferably, the surfactant is or comprises a non ionic surfactant. More preferably the non ionic surfactant has a HLB (or average weighted HLB if more than one) reasonably close to the required HLB (or average weighted required HLB if more than one) of the liquid wax. Other factors in the selection of the surfactants are those in which the hydrophilic end is more dominant than the hydrophobic end; those containing a fatty acid chain at its hydrophobic end which is not dissimilar to the fatty chains of the liquid wax; or is a polymeric surfactant; or is a combination of surfactants each with one or more of these properties. Hence, the skin feeling of the composition is favorable.
Interestingly, the method of manufacture is significant in producing a foam of good quality. For example, at 60% isostearic acid, if the polymer is dispersed in the liquid wax phase then only fairly good foam is achieved but if instead the polymer is added the water phase to form a gel and the surfactant is then added to the gel and finally the liquid wax phase is added to the composition (as described in the methodology) then a foam of good quality is produced even though the polymer is reduced.
At about 60% there may be tension to form a water in liquid wax emulsion and at about 70% oleyl alcohol there is significant tension to form a water in liquid wax emulsion. Surprisingly, by removing the polymer at 60% and at 70% oleyl alcohol the foam quality is improved.
Using 0.4% permulen with 3% polysorbate 80, which favours a liquid wax in water emulsion, did not release foam at 70% of oleyl alcohol. Increasing the surfactant to 5% or reducing the permulen to half resulted in a poor foam.
By using PEG 30 dipolyhydroxysearate instead of polysorbate 80 it is possible to form a water in liquid wax emulsion, however it produces poor foam with polymer and without polymer. On the other hand if polysorbate 80 is used as surfactant, which favours a liquid wax in water emulsion then a foam of excellent quality is achieved without polymer at 60% and at 70%.
Without being bound to any particular theory the physical change in the formulation may be due to oleyl alcohol reaching a concentration where phase reversal from liquid wax in water to water in liquid wax emulsion is possible. Also at this concentration range of oleyl alcohol removal of the polymeric agent, which itself can absorb water may—without being bound by any theory—perhaps reduce internal emulsion tensions resulting from the presence of the thickening polymeric agent and thereby unexpectedly resulting in improved foam quality even though polymeric agents are normally added to strengthen foam quality. Also as the concentration of oleyl alcohol increased and consequently the amount of water decreased it may be that the amount of surfactant required can be reduced as the external water phase is thinner.
It further might possibly be the case that—without being limited by any theory—for a given emulsion system as the liquid wax phase is increased with a corresponding decrease in the water phase the internal tension or pressure for phase reversal will increase and the point at which the phase reversal can occur can be retarded by selective use of non traditional derivatized polymeric agents with emulsifying properties, such as permulen that can stabilize the formulation and help improve resistance to creaming, they may in small amounts be able to push back the point at which pressure for phase reversal might otherwise occur but subject to the caveat that whilst removal of polymer may improve visual foam appearance it can result in a lesser resistance to creaming. By fine tuning of the formulations and or addition of other stabilizing substances resistance to creaming can be improved.
These compositions can be used as a vehicle for pharmaceutical and cosmetic agents especially those soluble in liquid waxes or water. For example imiquimod is soluble in isostearic acid.
Formulations 06, 09, 31, 39 and 44 were found to be substantially resistant to creaming when subjected to centrifugation at 3000 rpm for 10 minutes. With adjustment these formulations could be stable to centrifugation as can be seen from formulation 31, indicating that they should be substantially resistant to aging and physically shelf stable.
Oleyl alcohol is a defoamer and is therefore harder to formulate in foam formulations than octyldodecanol or isostearyl alcohol, which are also liquid fatty alcohols. Thus, by way of prophetic example the above formulations may be made with either octyldodecanol or isostearyl alcohol alone or in combination.
In order to create a foamable composition, the composition is filled into an aerosol canister and pressurized using a liquefied or gas propellant can be added at a concentration of about 3% to about 25%.
3(b) 12% Oleyl Alcohol (Liquid) with 8% Isostearyl Acid (Liquid) or 8% Stearic Acid (Solid)















HLB/RHLB
012
013



















Ingredients





Isostearic acid
13
8.00


Stearic acid
15.5

8.00


Oleyl alcohol
14
12.00
12.00


Ceteareth-20
15.2
0.90


Polysorbate 80
15

1.30


Glyceryl stearate
3.8
1.40
1.00


PEG 100 stearate
18.8
2.40
2.40


Purified water

75.30
75.30


Total

100.00
100.00


Propellant (AP-70)

8.00
8.00


Appearance


Quality

Good-Excellent
Good-Excellent


Color

White
White


Odor

No odor
No odor


Shakability

Good
Good


Microscope

No Crystals
No Crystals


Density

0.038
0.044


Bubble size (μM)

144.00
93.00


Bubble size

0.00
0.00


(above 500 μM)









Comments: Formulations with 12% oleyl alcohol as liquid wax were able to achieve good to excellent foam in combination either a liquid fatty acid or a solid fatty acid at 8%. As oleyl alcohol can have destabilising or defoaming properties especially as the concentration increases then prophetically replacing oleyl alcohol with another liquid alcohol such as octyldodecanol or isostearyl alcohol would be expected to yield foamable formulations which are similar or perhaps even better. Formulation 12 had good spreadabiliy, good skin feeling and quick absorption without a waxy sensation. Formulation 13 also had good spreadabiliy, good skin feeling and relatively quick absorption with a delicate waxy sensation.
A1—Example 4—Vehicle Compositions Containing Jojoba Oil
The following foamable vehicles were prepared and the quality of the resultant foam was ascertained.
















038
021
025
033




















Ingredients






Jojoba Oil
20
50
60
70


Pemulen TR-2
0.62
0.4
0.3
0.22


Polysorbate 80
3
3
3
3


Purified water
76.38
46.6
36.7
26.78


Control:
100
100
100
100


Propellant AP70
8
8
8
8


Results


PFF (pre foam


formulation)


Centrifugation 3K
20% cr.
40% cr.
10% cr.
stable



20% sep


Centrifugation 10K



30% cr.


Viscosity (cPs)

4025
6117


Microscopic
No
No
No
No


Observation
Crystals
Crystals
Crystals
Crystals


Foam


Appearance
G
G−
G−
G


Color
Yellowish
cream
cream
Yellowish


Odor
1
1
1
1


Shakability
Good
Moderate
Moderate
Moderate


Density (g/mL)
0.05
0.102
0.093
0.067


Microscopic
No
No
No
No


Observation
Crystals
Crystals
Crystals
Crystals


Collapse time
>300/G


>300/G


36° C. (sec)


Foam pH
3.79
3.93
4.08
4.19


(diluted 1:5)









These compositions contain 20%, 30%, 50%, 60%, and 70% of jojoba oil (otherwise is known as liquid wax), which somewhat resembles sebum in nature to provide (1) solubilizing capacity; and (2) potentially enhanced skin delivery of an active agent and (3) some emolliency and or (4) some organized chaos by virtue of its non linear shape enabling both shakability and flowability of the wax formulation and potentially enhanced skin penetration.
The compositions contain from about 66% to about 27% water. Therefore, they can provide a good skin feeling effect even at high concentrations.
Up to about 70% jojoba the compositions are believed to be wax in water emulsions, Liquid wax in water emulsion is maintained and stabilized by selecting a surfactant that favors liquid wax in water emulsions over water in liquid wax emulsions. Hence, the skin feeling of the composition is favorable.
Although at 70% oleyl alcohol and at 70% isostearic acid there is significant tension to form a water in liquid wax emulsion at 70% jojoba oil the composition can still form a liquid wax in water emulsion despite that water is only about a quarter of the composition. The extra stability of the emulsion may, without being bound to any particular theory, be ascribed to its much longer fatty chain back bone being about double of that of oleyl alcohol and of isostearic acid.
Also at this concentration range of jojoba oil removal of the polymeric agent, which itself can absorb water may—without being bound by any theory—perhaps reduce internal emulsion tensions resulting from the presence of the thickening polymeric agent and thereby unexpectedly resulting in improved foam quality even though polymeric agents are normally added to strengthen foam quality. Also as the concentration of jojoba oil increased and consequently the amount of water decreased it may be that the amount of surfactant required can be reduced as the external water phase is thinner.
It further appears to be the case that—without being limited by any theory—for any given emulsion system as the liquid wax phase is increased with a corresponding decrease in the water phase the internal tension or pressure for phase reversal will increase and the point at which the phase reversal can occur can be retarded by selective use of non traditional derivatized polymeric agents with emulsifying properties, such as permulen that can stabilize the formulation and help improve resistance to creaming, they may in small amounts be able to push back the point at which pressure for phase reversal might otherwise occur but subject to the caveat that whilst removal of polymer may improve visual foam appearance it can result in a lesser resistance to creaming. By fine tuning of the formulations and or addition of other stabilising substances resistance to creaming can be improved.
A foam of quality was not achieved with only permulen and oleyl alcohol.
These compositions can be used as a vehicle for pharmaceutical and cosmetic agents especially those soluble in liquid waxes or water. For example, imiquimod is soluble in isostearic acid.
In order to create a foamable composition, the composition is filled into an aerosol canister and pressurized using a liquefied or gas propellant can be added at a concentration of about 3% to about 25%.
Example 5
Fatty Alcohol Combination Emulsion Formulations















HLB/RHLB
002
004



















Ingredients





Oleyl alcohol
14
19.00
19.00


Isostearyl alcohol
~13
19.00
19.00


Octyldodecanol
~14
19.00
19.00


Cetearyl alcohol
15.5
2.00
3.00


Ceteareth-20
15.2

2.90


Polysorbate 60
14.9
4.00


Polysorbate 80
15

2.40


Glyceryl stearate
3.8
1.00
0.70


PEG 100 stearate
18.8
1.00


Sorbitane stearate
4.7


PEG-30 dipolyhydroxystearate
5.5


Purified water

35.00
34.00


Total

100.00
100.00


Propellant (AP-70)

8.00
8.00


Appearance


Quality

Poor
Good+


Color


White


Odor


No odor


Shakability


Good


Bubble size (μm)


149.00


Bubble size


0.00


(above 500 μm)


Hardness


13.13









Comments: It is possible to achieve good quality foam with high concentrations (about 60%) of fatty alcohol emulsion formulation by using only surfactants. The foam quality was greatly improved by increasing the solid fatty alcohol from 2% to 3% and changing the surfactants. The formulations may comprise a single fatty alcohol (See Example 3) or combinations of two or three or more fatty alcohols (See Example 5).
Example 6:  ̃57% Isostearic Acid and 5% Imiquimod Using a Polymeric Surfactant Pemulen













009 (cf 032)



















Ingredients




Isostearic acid
56.90



Pemulen TR-2
0.30



Polysorbate 80
3.00



Purified water
34.80



Imiquimod
5.00



Total
100.00



Propellant AP70
8.00



Results



Foam quality
Good



Color
White



Odor
No Odor



Shakability
Good



Microscopic
No Crystals



Observation










Comments: This formulation is based on the vehicle 32 of Example 1 which produced good quality foam. The addition of imiquimod did not destabilize the formulation and the imiquimod was fully dissolved with no crystals being microscopically observed.
Section B—Aqueous Solid Wax Formulations
B1—Example 7—Vehicle Composition Containing Stearic Acid
The following foamable vehicles were prepared and the quality of the resultant foam was ascertained.













024



















Ingredients




Stearic acid
30



Polysorbate 80
10



Purified water
60



Control:
100



Propellant Butane
20



Results



PFF (pre foam formulation)



Microscopic Observation
Crystals



Foam



Appearance
G



Color
white



Microscopic Observation
Crystals










Compositions contain up to about 30% stearic acid to provide (1) some emolliency; (2) body as a waxy thickener; (3) possibly some solubilizing capacity; and (4) possibly enhanced skin delivery of an active agent.
The compositions are wax in water emulsions and contain from about 60% water. Therefore, they can provide a good skin feeling effect even at high stearic acid concentrations.
As a foam adjuvant in foamable formulations stearic acid is used at concentrations of up to about 5% and preferably between about 1% and about 3%. Beyond 5% it is used as a thickening agent although usually at levels of not more than at about 8%. Its use beyond about 9% for foamable compositions was thought inappropriate since it would tend to support the formation of a solid block from which it was not possible to make a foam especially where traditional types of polymeric agents and or solid surfactants, were used in the formulations for example, CMC at levels of say up to or about 5% and or steareth 21 at levels of say up to or about 5%. Surprisingly it was discovered that is was possible to use much higher levels of stearic acid to produce foamable compositions of good quality by avoiding the use of polymeric agents, by using liquid surfactants and by use of higher levels of hydrophobic propellant. As the level of stearic acid approaches about 30% it tends towards not releasing foam. However, by selective use of liquid surfactants in higher concentrations and or higher levels of hydrophobic propellants it was possible to achieve a shakable flowable composition, which produced good quality foam. Thus, the upper limit of stearic acid that can be used in a foamable composition is determined by its shakability and more importantly its flowability.
For example, where stearic acid is 30% and only 3% Polysorbate 80 is used poor foam is obtained. However, by increasing the liquid surfactant to about 10% so it acts as both as a solvent and as a surfactant and raising the propellant to 20% then surprisingly it was possible to obtain a foam of good quality based on a wax/water/surfactant composition even at such high levels of solid wax in water. However crystals were observed. This problem was overcome by formulating liquid with solid wax. Thus as can be seen in Example 7 in the presence of liquid wax no crystals were observed in 30% stearic acid formulations.
Solid waxes form a wax in water emulsion when heated in the presence of surfactant with agitation, however unlike liquid wax or liquid waxy substances they cool to form solid lipid like suspensions having unique roundish particles that cannot be obtained from milling, which suspensions nevertheless appear to be like emulsions.
A foam of quality was not achieved with only permulen and 30% stearic acid. Addition of polysorbate 80, a liquid surfactant, did not appear to make a significant difference at a usual surfactant level of 3%.
These compositions can be used as a vehicle for pharmaceutical and cosmetic agents especially those soluble in waxes or water.
In order to create a foamable composition, the composition is filled into an aerosol canister and pressurized using a liquefied or gas propellant can be added at a concentration of about 3% to about 35%. Preferably between 12% to 25%.
Section C—Aqueous Formulation with Liquid and Solid Wax
C1—Example 8—Vehicle Composition Containing Oleyl Alcohol, Stearyl Alcohol, Cetyl Alcohol and Stearic Acid
The following foamable vehicles were prepared and the quality of the resultant foam was ascertained.













001



















Ingredients




Stearic acid
30



Cetyl alcohol
4



Stearyl alcohol
3



Caprilic/capric triglycerides
2.5



Oleyl alcohol
7.5



Sorbitan Stearate
0.65



Benzyl alcohol
2



Xanthan gum
0.35



Hydroxypropyl methylcellulose
0.35



Glycerin
2



Polysorbate 60
2.5



Methyl hydroxybenzoate
0.2



Propyl hydroxybenzoate
0.02



Purified water
44.93



Control:
100



Propellant AP70
8



Results



PFF (pre foam formulation)



Microscopic Observation
No Crystals



Foam



Visual inspection
Homogeneous



(pressurized glass bottle)



Appearance
G



Color
White



Odor
no odor



Shakability
poor



Density (g/mL)
0.04



Microscopic Observation
No Crystals



Collapse time 36° C. (sec)
>300/G



Foam pH (diluted 1:5)
4.65










Surprisingly it was possible to make aqueous foam compositions of good quality with solid wax of up to about 37% by addition of about 7.5% liquid wax. The upper amount of solid wax that may be added is such that the formulation remains substantially flowable. Also by using (and increasing the amount of) surfactant in which the solid wax dissolves—preferably a liquid surfactant—it may be possible to increase further the amount of solid wax in the formulation.
C1—Example 9—Vehicle Composition Containing Isostearic Acid and Stearic Acid
The following foamable vehicles were prepared and the quality of the resultant foam was ascertained.
















023
027
029
030




















Ingredients






Isostearic acid
40
45
55
50


Stearic acid
30
25
15
20


Arlacel P-135
2
2
2
2


Sodium Chloride
0.5
0.5
0.5
0.5


Purified water
27.5
27.5
27.5
27.5


Control:
100
100
100
100


Propellant AP70 (except in 23)
10 butane
8
8
8


Results


PFF (pre foam formulation)


Centrifugation 3K
—
90% cr.
—
—


Centrifugation 10K
—

—
—


Viscosity (cPs)
—
12407
—
—


Microscopic Observation
—
No Crystals
—
—


Foam
—

—
—


Appearance
FG/G
G
FG
FG


Color
—
White
—
—


Odor
—
1
—
—


Shakability
—
Good
—
—


Microscopic Observation
—
No Crystals
—
—









By making effective use of and combining the surprising properties of liquid waxes with the special characteristics of solid waxes it was surprisingly found possible to make formulations of about 70% waxes, which are shakable, flowable and form foams of fairly good and of good quality even where solid wax is present at a concentration of 30%.
Such compositions contain 40% to 55% isostearic alcohol to provide (1) solubilizing capacity; and (2) potentially enhanced skin delivery of an active agent and (3) some emolliency and or (4) some substantially organized chaos by virtue of its non linear shape enabling both shakability and flowability of the wax formulation and potentially enhanced skin penetration. In one particular embodiment, the ratio of isostearic acid to stearic acid is about 9:5.
It is believed that even higher concentrations of isostearic acid may be reached by reducing the water alone or in combination with a reduction of stearic acid. It is also expected that replacement of isostearic acid with oleyl alcohol would produce similar results save that—as oleyl alcohol produces formulations which are a little thicker than those with the same amount of isostearic acid—possibly the oleyl alcohol formulations might not be able to accommodate as higher level of stearic acid as can isostearic acid. Formulations with lower levels of isostearic acid are clearly possible.
The compositions in the example contain about 27% water. Therefore, they can provide a relatively good skin feeling effect even at such high wax concentrations.
Formulation 27 was examined by water addition test and was found to be water in liquid wax emulsion. By use of a surfactant favoring wax in water emulsions as seen elsewhere in the Examples it may be possible to achieve a water in liquid wax emulsion even at these high concentrations.
These compositions can be used as a vehicle for pharmaceutical and cosmetic agents especially those soluble in liquid waxes or water. For example imiquimod is soluble in isostearic acid.
In order to create a foamable composition, the composition is filled into an aerosol canister and pressurized using a liquefied or gas propellant can be added at a concentration of about 3% to about 25%.
C1—Example 10—Vehicle Composition Containing Isostearic Acid, One or More of Oleyl Alcohol, Cetyl Alcohol and Stearyl Alcohol, and Active Agent
The following foamable vehicles were prepared and the quality of the resultant foam was ascertained.
















003
005
006
007




















Ingredients






Isostearic acid
30
25
25
25


Cetyl alcohol
4
2.2
2.2
—


Stearyl alcohol
3
3.1
3.1
3.1


Caprilic/capric
2.5
—
—
—


triglycerides


Oleyl alcohol
7.5
—
—
—


White soft
—
3
3
3


paraffin


Sorbitan Stearate
0.65
0.6
0.6
0.6


PEG-40 Stearate
—
—
—
1


Imiquimod
5
5
5
5


Benzyl alcohol
2
2
2
2


Xanthan gum
0.35
0.5
0.25
0.25


Hydroxypropyl
0.35
0.5
0.25
0.25


methylcellulose


Glycerin
2
2
2
2


Polysorbate 60
2.5
3.4
3.4
3.4


Methyl
0.2
0.2
0.2
0.2


hydroxybenzoate


Propyl
0.02
0.02
0.02
0.02


hydroxybenzoate


Purified water
39.93
52.48
52.98
54.18


Control:
100
100
100
100


Propellant AP70
8
8
8
8


Results


Foam Quality
G
G/block
FG
G


Shakability
shakable
No
shakable
shakable




shakability




but some




flowability


Color
White
White
White
White


Odor
No odor
No odor
No odor
No odor


Density
0.068
0.071
0.059
0.049


Collapse time
>300
—
>300
>300


(sec)


Microscopic
No
No
No
No


observation
crystals
crystals
crystals
crystals


Centrifugation
homo-
homo-
homo-
homo-


3000 rpm
geneous
geneous
geneous
geneous









These compositions contain 30% isostearic acid and about 3% stearyl alcohol. Optionally they may also contain one or more of some cetyl alcohol, oleyl alcohol and capric caprylic triglycerides to provide (1) emolliency; (2) solubilizing capacity; and (3) potentially enhanced skin delivery of an active agent and or (4) some organized chaos by virtue of the non linear shape of the liquid waxes enabling both shakability and flowability of the wax formulation and potentially enhanced skin penetration.
The compositions contain about 40% to about 55% water. Therefore, they provide a good skin feeling effect.
The compositions are oil in water emulsions. Hence, the skin feeling of the composition is favorable.
The compositions can be used for topical therapy of a skin disorder treatable by imiquimod, which can include treating, containing, ameliorating or preventing actinic keratosis, superficial basal cell carcinoma and external genital warts.
These compositions can be used as a vehicle for other pharmaceutical and cosmetic agents especially those soluble in liquid waxes or water.
In order to create a foamable composition, the composition is filled into an aerosol canister and pressurized using a liquefied or gas propellant can be added at a concentration of about 3% to about 25%.
Example 11: Isostearic Acid and Stearic Acid Emulsion Formulations—Minimum Ingredients















Ex. 7 (029)
Ex. 7 (029)


cf
HLB/RHLB
001-
003


















Isostearic acid
13
55.00
55.00


Stearic acid
15.5
15.00
15.00


Ceteareth-20
15.2

2.50


Polysorbate 80
15
2.60


Sorbitane oleate
4.3
0.40


Sorbitane stearate
4.7

0.50


Purified water

27.00
27.00


Total

100.00
100.00


Propellant (AP-70)

8.00
8.00


Appearance


Quality

Good−
Good+


Color

White
White


Odor

No odor
No odor


Shakability

Good
Good









Comments: It is possible to achieve good quality foam with high concentrations (70%) of fatty acids by using only surfactants. In the two formulations the ratio of solid to liquid fatty acids is about 3:11.
Methodology for formulations 001-006 in Examples 5, 11, 12 and for formulations 012 and 013 in Example 3(b):

    
    
        1) Heat all ingredients (other than water) to 60-70 C to complete dissolution.
        2) Heat water to 60-70 C.
        3) Add water to 1 while mixing. Mix for about 10 minutes.
        4) Cool to RT while mixing. Add water to adjust formulation to 100% while mixing.
    
    


Methodology for formulation 007 in Example 12:

    
    
        1) Heat all ingredients (other than water, xanthan gum, hydroxypropyl methylcellulose, benzyl alcohol and glycerin) to 60-70 C to complete dissolution.
        2) Add Xanthan gum and Hydroxypropyl methylcellulose to water at RT to dissolve. Heat to 60-70 C.
        3) Add 2 to 1 while mixing. Mix for about 10 minutes. Alternatively 1 can be added to 2.
        4) Cool to RT while mixing. Add Benzyl alcohol and Glycerin. Add water to adjust formulation to 100% while mixing.
    
    


Methodology for formulation 008 in Example 13:

    
    
        1) Heat Isostearic acid to 60-70 C. Add Imiquimod to complete dissolution. Add Stearic acid and PEG-30 dipolyhydroxystearate to complete dissolution.
        2) Add Sodium Chloride to water at RT to dissolve. Heat to 60-70 C.
        3) Add 2 to 1 while mixing. Mix for about 10 minutes. Alternatively 1 can be added to 2.
        4) Cool to RT while mixing. Add water to adjust formulation to 100% while mixing.
    
    


Methodology for formulation 009 in Example 6:

    
    
        1) Heat Isostearic acid to 60-70 C. Add Imiquimod to complete dissolution.
        2) Add Pemulen TR-2 to water at RT to dissolve. Heat to 60-70 C. Add Polysorbate 80 to complete dissolution.
        3) Add 2 to 1 while mixing. Mix for about 10 minutes. Alternatively 1 can be added to 2.
        4) Cool to RT while mixing. Add water to adjust formulation to 100% while mixing.
    
    


Methodology for formulation 31 in Example 5 which can be applied to the other formulations in Example 5:

    
    
        1) Heat Oleyl alcohol to 60-70 C.
        2) Add Pemulen TR-2 to water at RT to dissolve. Heat to 60-70 C. Add Polysorbate 80 to complete dissolution.
        3) Add 2 to 1 while mixing. Mix for about 10 minutes. Alternatively 1 can be added to 2.
        4) Cool to RT while mixing. Add water to adjust formulation to 100% while mixing.
    
    


Example 12: Combination of High Fatty Acid and Fatty Alcohols Emulsion Formulations
















Ex. 6
Ex. 6
Ex. 6




(001)
(001)
(001)


cf
HLB/RHLB
005
006
007



















Caprilic/capric
5
2.50
2.50
10.00


triglycerides


Stearic acid
15.5
30.00
30.00
30.00


Oleyl alcohol
14
7.50
7.50


Cetyl alcohol
15.5
4.00
4.00
4.00


Stearyl alcohol
15.5
3.00
3.00
3.00


Polysorbate 60
14.9


2.70


Polysorbate 80
15
3.00
4.00


Sorbitane oleate
4.3
0.60
0.10


Sorbitane stearate
4.7


0.50


PEG 100 stearate
18.8
1.40


Purified water

48.00
48.90
45.10


Benzyl alcohol



2.00


Glycerin



2.00


Xanthan gum



0.35


Hydroxypropyl



0.35


methylcellulose






Total

100.00
100.00
100.00


Propellant

8.00
8.00
8.00


(AP-70)


Appearance


Quality

Good
Good
Good


Color

White
White
White


Odor

No odor
No odor
No odor


Shakability

Poor
Poor
Poor


Microscope

Not
Not
No




measured
measured
crystals









It is possible to achieve good foam in high concentration (47%) of fatty alcohol, fatty acid and emollient emulsion formulations by using only surfactants. Crystals are seen with 30% stearic acid without fatty alcohol. Surprisingly, the addition of fatty alcohols to a high level of fatty acid (30%) which is otherwise insoluble results in the absence of crystals on microscopic observation. The presence of liquid hydrophobic solvent may contribute to this effect.
Example 13: Emulsion Formulations with Solid and Liquid Fatty Acids

















Ex. 7 (027)



cf
HLB/RHLB
008




















Isostearic acid
13
42.70



Stearic acid
15.5
23.70



PEG-30 dipolyhydroxystearate
5.5
2.00



Purified water

26.10



Sodium Chloride

0.50



Imiquimod

5.00



Total

100.00



Propellant (AP-70)

8.00



Appearance



Quality

Good



Color

White



Odor

No odor



Shakability

Poor



Microscope

No crystals










It is possible to achieve good foam with high concentrations (66.4%) of solid and liquid fatty acids combined using only one surfactant. The ratio of solid to liquid fatty acids is about 1:2. While using liquid hydrophobic solvent, no crystals of Imiquimod were observed.
Section D—Pharmaceutical and Cosmetic Formulations
D1—Example 14—Exemplary Prophetic Foams Containing Active Pharmaceutical Ingredients (API)
Exemplary concentrations of active ingredients in foamable compositions are set out in Table 2 and in the following additional prophetic examples. Each active ingredient is added into, for example, any of the carriers listed in any of the above Examples in a therapeutically effective concentration and amount. The methodology of addition is well known to those of the art. The composition is adjusted in each case so that it is made up to 100% w/w by addition or reduction of water or a wax or waxy substance, counterpart or derivative or other solvent as is appropriate to the active agents concerned.
A—Exemplary Concentration Ranges of Some APIs which are Addable to Foams









TABLE 2






Concentra-



Class
tion
Exemplary Use







Hydrocortisone
1%
Steroid responsive inflammation


acetate

and psoriasis or atopic dermatitis


Betamethasone
0.12%  


valerate


Clobetasol
0.05%  


proprionate


Acyclovir
5%
Viral infection, herpes


Ciclopirox
1%
Fungal infection, seborrhea,




dandruff,


Clindamycin
 1-2%
Bacterial infection, acne, rosacea,


Azelaic acid
15% 
Acne, rosacea, pigmentation




disorder and various dermatoses


Metronidazol
0.25%-2%   
Rosacea, bacterial infections and




parasite infestations


Diclofenac
1%
Osteoarthritus, joint pain


Tacrolimus
0.2%  
Atopic dermatitis, eczema and




inflammation


Caffeine
5%
anti-cellulite


Clotrimazole
1%
Fungal infection


Lidocaine base
2%
Local anaesthetic


Terbinafine HCL
1%
Fungal infection


Gentamycin
0.1%  
Bacterial skin infections, burns or




ulcers


Dexpanthenol
5%
Wounds, ulcers, minor skin




infections


Urea
 5-10%
Emollient and keratolytic




Atopic dermatitis, eczema,




ichthyosis and hyperkeratotic skin




disorders


Ammonium lactate
 12%-17.5%
Dry scaly conditions of the skin




including ichthyosis


Povidone-iodine
10% 
Antimicrobial - antiseptic


Benzoyl peroxide
1%-10%
Acne


Alpha-hydroxy
1%-20%
Aging, wrinkles


acids


Salicylic acid
1%-10%
Acne


Hydroquinone
1%-10%
Pigmentation disorders


Calcipotriol
0.005
Psoriasis


Ilmiquimod
1%-5% 
Skin cancers, genital warts









B—Prophetic Steroid Compositions

The following steroids can be included in carriers, compositions and foams: betamethasone valerate 0.12%, clobetasol propionate 0.05%, betamethasone dipropionate 0.05%, fluocinolone acetonide 0.025%, hydrocortisone acetate 0.5% and hydrocortisone butyrate 0.1%.
C—Prophetic Vitamin and Steroid Compositions
Additionally, one or more of the following vitamins can be included in the carriers, compositions and foams: vitamin C (ascorbic acid) between 0.1 and 5%; for example, 0.1% 1%, 2% 3%, 4%, or 5%; vitamin C (magnesium ascorbyl phosphate) 3%, retinol 1%, retinoic acid 0.1%, niacinamide 2% and tocopherol 1% and Vitamin K. between 0.1 and 2%, for example, 0.1% or 1% or 2%.
D—Prophetic Vitamin Compositions with or without an Additional Therapeutic Agent
Foamable vitamin compositions at 0.1%, 1%, 2%, 3%, 4%, or 5%, by weight of composition are made up with or without an active agent and added to any of the vehicles or compositions illustrated in the above Examples.
E—Prophetic Microsponge Formulations.
The following microsponges can be included in any of the carriers, compositions and foams described herein or exemplified in any of the preceding examples.















Ingredients
w/w %
w/w %
w/w %
w/w %
w/w %




















Microsponge
1.00
3.00%
5.00%
10.00%
15.00


polymer


hydrophobic
99.00
97.00
95.00
90.00
85.00


wax in water


emulsion



Total
100.00
100.00
100.00
100.00
100.00


Propellant
8-00
8-00
8-00
8-00
8-00


AP-70%









Procedure to prepare formulations with microsponge polymer.
1.) Prepare a hydrophobic wax in water emulsion as described herein.
2.) When the formulation is at room temperature, the microsponge polymer encapsulating the active agent(s) is added and the formulation is mixed for about 5 to about 10 minutes until a uniform dispersion is obtained.
Note: Where Drug Microsponge X % w/w is provided it refers to the microsponges including the trapped drug and any other ingredients incorporated when loading the microsponges.
E—Different Drug Classes
All the above examples represent different drug classes and it is to be understood that other drugs belonging to each of the classes represented above or described elsewhere in the specification may be included and may be used in the compositions in a safe and effective amount.

## Claims

1. A foamable composition for a pharmaceutical comprising:
A. a carrier comprising:
a. at least about 20% by weight of a liquid wax comprising one or more free fatty acids, wherein at least one free fatty acid is oleic acid and wherein the oleic acid is at least about 20% by weight of the carrier;
b. a surface-active agent;
c. a polymeric agent; and
d. a solid wax comprising a solid paraffin wax;

wherein the ratio of liquid wax to solid wax is about 3:1 to about 10:1, and
B. a liquefied hydrocarbon gas propellant at a concentration of about 3% to about 35% by weight of the foamable composition;
wherein the composition has a water content less than about 5% by weight;
wherein the composition is not an emulsion; and
wherein, upon release from a pressurized container, a breakable foam is produced.

2. The foamable composition of claim 1, wherein the solid wax further comprises a solid wax selected from the group consisting of a fatty acid, a fatty alcohol, a microcrystalline wax, a petroleum wax, a polyethylene wax, a beeswax, a candelilla wax, a castor wax, a Chinese wax, a Fischer-Tropsch wax, a rice bran wax, a tallow, a wool wax, and a mixture of any two or more thereof.

3. The foamable composition of claim 2, wherein the solid wax further comprises a solid wax selected from the group consisting of stearic acid, cetyl alcohol, behenyl alcohol, stearyl alcohol, and a mixture of any two or more thereof.

4. The foamable composition of claim 1, wherein the liquid wax enables the solid wax to solubilize.

5. The foamable composition of claim 1, wherein solid wax crystals are not visible and the composition is flowable through an aerosol valve.

6. The foamable composition of claim 1, wherein the polymeric agent is present in the composition at a concentration of about 0.01% to about 5% by weight of the carrier and is selected from the group consisting of a bioadhesive agent, a gelling agent, a film forming agent, and a phase change agent.

7. The foamable composition of claim 1, wherein the surface-active agent is selected from the group consisting of a polysorbate, polyoxyethylene (20) sorbitan monostearate, polyoxyethylene (20) sorbitan monooleate, a polyoxyethylene fatty acid ester, polyoxyethylene (8) stearate, polyoxyethylene (20) stearate, polyoxyethylene (40) stearate, polyoxyethylene (100) stearate, a polyoxyethylene alkyl ether, a polyoxyethylene cetyl ether, polyoxyethylene (23) cetyl ether, polyoxyethylene (2) cetyl ether, polyoxyethylene (10) cetyl ether, a sucrose ester, a partial ester of sorbitol, sorbitan monolaurate, a monoglyceride, a diglyceride, isoceteth-20, steareth 2, glyceryl stearate, steareth-21, sorbitan stearate, laureth 4, sorbitan monooleate, ceteareth 20, steareth 20, ceteth 20, macrogol cetostearyl ether, PEG-30 dipolyhydroxystearate, sucrose distearate, cetomacrogol ether, cetearyl glucoside, polysorbate 20; methyl glucose sesquistearate, a sucrose stearic acid ester, a phospholipid, and a mixture of any two or more thereof.

8. The foamable composition of claim 7, wherein the surface-active agent is selected from the group consisting of sorbitan stearate, glyceryl monostearate, and a mixture thereof.

9. The foamable composition of claim 1, wherein the surface active agent also functions as a solvent.

10. The foamable composition of claim 1, wherein the polymeric agent is selected from the group consisting of a cross-linked polyacrylate polymer, acrylates/C10-30 alkyl acrylate crosspolymers, a locust bean gum, sodium alginate, sodium caseinate, an egg albumin, a gelatin agar, a carrageenin gum, a xanthan gum, a quince seed extract, a tragacanth gum, a guar gum, a cationic guar, a hydroxypropyl guar gum, a starch, an amine-bearing polymer, a chitosan, an alginic acid, a hyaluronic acid, a chemically modified starch, a carboxyvinyl polymer, a polyvinylpyrrolidone, a polyvinyl alcohol, a polyacrylic acid polymer, a polymethacrylic acid polymer, a polyvinyl acetate, a polyvinyl chloride polymer, a polyvinylidene chloride polymer, a methylcellulose, a hydroxypropyl cellulose, a hydroxypropyl methylcellulose, a hydroxyethyl cellulose, a methylhydroxyethylcellulose, a carboxymethylcellulose, a hydroxyethylcarboxymethylcellulose, a cationic cellulose, an aluminum starch octenylsuccinate, a sodium starch octenylsuccinate, and a mixture of any two or more thereof.

11. The foamable composition of claim 1, wherein the composition further comprises a solvent selected from the group consisting of an organic carrier, a hydrophilic solvent, a hydrophobic solvent, a potent solvent, a polar solvent, a silicone, an emollient, and a mixture thereof.

12. The foamable composition of claim 11, wherein the solvent comprises dimethyl sulfoxide.

13. The foamable composition of claim 11, wherein the solvent comprises a polyethylene glycol.

14. The foamable composition of claim 1, wherein the surface active agent is between about 0.2% to about 8% by weight.

15. The foamable composition of claim 1, further comprising an additional component selected from the group consisting of a modulating agent, a polar solvent, an anti perspirant, an anti-static agent, a buffering agent, a bulking agent, a chelating agent, a colorant, a conditioner, a deodorant, a diluent, a dye, an emollient, fragrance, a humectant, an occlusive agent, a penetration enhancer, a perfuming agent, a permeation enhancer, a pH-adjusting agent, a preservative, a skin penetration enhancer, a sunscreen, a sun blocking agent, a sunless tanning agent, a vitamin, and a mixture of any two or more thereof.

16. The foamable composition of claim 1, further comprising an active agent.

17. The foamable composition of claim 16, wherein at least 95% of the active ingredient has been solubilized.

18. The foamable composition of claim 16, wherein the active agent is selected from the group consisting of an active herbal extract, an acaricide, an age spot and keratose removing agent, an allergen, an analgesic, a local anesthetic, an antiacne agent, an antiallergic agent, an antiaging agent, an antibacterial, an antibiotic, an antiburn agent, an anticancer agent, an antidandruff agent, an antidepressant, an antidermatitis agent, an antiedemic, an antihistamine, an antihelminth, an antihyperkeratolyte agent, an antiinflammatory agent, an antiirritant, an antilipemic, an antimicrobial, an antimycotic, an antiproliferative agent, an antioxidant, an anti-wrinkle agent, an antipruritic, an antipsoriatic agent, an antirosacea agent, an antiseborrheic agent, an antiseptic agent, an antiswelling agent, an antiviral agent, an antiyeast agent, an astringent, a topical cardiovascular agent, a chemotherapeutic agent, a corticosteroid, a dicarboxylic acid, a disinfectant, a fungicide, a hair growth regulator, a hormone, a hydroxy acid, an immunosuppressant, an immunoregulating agent, an immunomodulatory, an insecticide, an insect repellent, a keratolytic agent, a lactam, a metal oxide, a mitocide, a neuropeptide, a steroid, a non-steroidal anti-inflammatory agent, an oxidizing agent, a pediculicide, a photodynamic therapy agent, a retinoid, a sanative, a scabicide, a vasoconstrictor, a vasodilator, a vitamin, a vitamin D derivative, a wound healing agent, a wart remover; an agent having activity against superficial basal cell carcinomas, actinic keratoses, Bowen's disease, or other squamous cell carcinomas and molluscum contagiosum; an agent having activity against herpes simplex virus infections, other viral infections, or eczema; a vaccine adjuvant, and a mixture of any two or more thereof.

19. The foamable composition of claim 18, wherein the active agent is an anti-cancer agent.

20. A method of treating or ameliorating a skin, mucosal or body cavity cancer disorder of a mammalian subject, comprising administering the foamable composition of claim 19 to the skin, a mucosal surface, or a body cavity of said mammalian subject.

21. The method of claim 20, wherein the cancer disorder is selected from the group consisting of skin neoplasia, skin neoplasms, skin cancer, ischemic necrosis, moles, Kaposi's sarcoma, melanoma, basal cell carcinoma, squamous cell carcinoma, scleroderma, vulvar intraepithelial neoplasia, genital cancer, cancer of the cervix, cancer of the vulva, cancer of the vagina, anal cancer, polyps of the colon and rectum, superficial basal cell carcinomas, and Bowen's disease.

22. A foamable composition for a pharmaceutical comprising:
A. a carrier comprising:
a. a solvent comprising:
i. at least about 20% by weight of a liquid wax comprising one or more free fatty acids, wherein at least one free fatty acid is oleic acid and wherein the oleic acid is at least about 20% by weight of the carrier; and
ii. at least one potent solvent, wherein the concentration of the potent solvent is more than about 60% by weight of the solvent;

b. a surface-active agent;
c. a polymeric agent; and
d. a solid wax comprising a solid paraffin wax;

wherein the ratio of liquid wax to solid wax is about 3:1 to about 10:1, and
B. a liquefied hydrocarbon gas propellant at a concentration of about 3% to about 35% by weight of the foamable composition;
wherein,
the foamable composition a water content less than about 5% by weight;
wherein the foamable composition is not an emulsion; and
upon release from a pressurized container, a breakable foam is produced.

23. The foamable composition of claim 1, wherein the solid wax comprises a paraffin wax, stearyl alcohol, behenyl alcohol, or a mixture of any two or more thereof; wherein the surface-active agent comprises glyceryl monostearate, sorbitan monostearate, or a mixture thereof; wherein the polymeric agent comprises a methylcellulose; wherein the composition further comprises a polar solvent comprising dimethyl sulfoxide, polyethylene glycol, or a mixture thereof; and wherein the composition further comprises an anti-cancer agent.

24. The foamable composition of claim 1, wherein the surface active agent is between about 0.2% to about 8% by weight; wherein the polymeric agent is present in the composition at a concentration of about 0.01% to about 5% by weight, and wherein the composition further comprises a polar solvent at a concentration of about 40% to about 80% by weight.

25. The foamable composition of claim 22, wherein the solid wax further comprises stearyl alcohol, behenyl alcohol, or a mixture thereof; wherein the surface-active agent comprises glyceryl monostearate, sorbitan monostearate, or a mixture thereof; wherein the polymeric agent comprises a methylcellulose; wherein the potent solvent comprises dimethyl sulfoxide, polyethylene glycol, or a mixture thereof; and wherein the composition further comprises an anti-cancer agent.

26. The foamable composition of claim 22, wherein the surface active agent is between about 0.2% to about 8% by weight; wherein the polymeric agent is present in the composition at a concentration of about 0.01% to about 5% by weight.

27. The foamable composition of claim 22, wherein the composition is waterless.

28. The foamable composition of claim 1, wherein the composition has a water content of less than about 2%.

29. The foamable composition of claim 1, wherein the composition has a water content of less than about 1.5%.

30. The foamable composition of claim 22, wherein the composition has a water content of less than about 2%.

31. The foamable composition of claim 22, wherein the composition has a water content of less than about 1.5%.