WO2020069225A1

WO2020069225A1 - Phmb compositions and methods of treatment for skin cancer

Info

Publication number: WO2020069225A1
Application number: PCT/US2019/053305
Authority: WO
Inventors: Bradley BURNAM
Original assignee: Global Health Solutions Llc
Priority date: 2018-09-26
Filing date: 2019-09-26
Publication date: 2020-04-02

Abstract

Compositions and methods for the treatment of skin cancer, including basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (SCC). The compositions include a pharmaceutically effective amount of polyhexamethylene biguanide (PHMB) in petrolatum or another pharmaceutically acceptable carrier.

Description

PHMB COMPOSITIONS AND METHODS OF TREATMENT FOR SKIN CANCER

CROSS-REFERENCE TO REUATED APPUICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial Number 62/736,621, entitled “Petrolatum-Based PHMB Compositions and Methods of Treatment for Skin Cancer,” filed September 26, 2018, the contents of which are incorporated by reference herein, for all purposes, in its entirety.

FIEUD

[0002] The present disclosure is broadly concerned with petrolatum-based cationic- biocide compositions for the treatment and prevention of skin cancer. The disclosure is also concerned with methods for the treatment of skin cancer using petrolatum-based polihexanide biguanide (PHMB) compositions.

BACKGROUND

[0003] Skin cancer is one of the most prevalent forms of cancer in humans. Basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and malignant melanoma (MM) are the most frequent cutaneous malignant tumors, the incidence of which appears to be increasing. The three malignant cutaneous tumors are commonly associated with habitual exposure of the skin to sunlight resulting in chronic ultraviolet (UV)-induced damage. However, it is well accepted that the pathogenesis of the three cutaneous malignant tumors differs. Basal cell carcinoma (BCC) is associated with genetic mutations that induce the proliferation of basal cells as caused by uncontrolled activation of the hedgehog signal pathway. However, BCC generally follows an innocent course that is different than that of SCC and MM. Cutaneous squamous cell carcinoma (SCC) is primarily caused by multiple genetic mutations that enhance dysregulation of the cell cycle that is evoked by TP53 mutation.

[0004] Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the more frequently occurring types of skin cancer. There are an estimated three million people diagnosed with some form of BCC or SCC each year in the United States alone. While generally not as aggressive as highly malignant melanoma (MM) skin cancers, BCC and SCC pose a serious health burden and are capable of causing severe local damage if left untreated. Accordingly, additional methods of treatment for skin cancer, particularly BCC and SCC, are desired. In particular, a topical composition capable of treating BCC and SCC, and/or precancerous lesions, is desired.

[0005] Topical anticancer agents, such as 5-Fluoro uracil (5-FU), are limited by poor skin penetration, poor retention at the target site, and high skin irritation potential. Accordingly, topical compositions capable of enhancing the skin penetration of topical anticancer agents and/or the retention of topical anticancer agents at the target site are desirable. Further, topical compositions capable of reducing the skin irritation of topical anticancer agents are also desirable.

BRIEF DESCRIPTION OF THE FIGURES

[0006] The application file contains at least one photograph executed in color. Copies of this patent application publication with color photographs will be provided by the Office upon request and payment of the necessary fee.

[0007] FIG. 1 depicts an image of the formulation structure when using the mixing methodology disclosed herein for permanently encapsulating polyhexamethylene biguanide (PHMB) as nanodroplets into petrolatum without an emulsifier, according to an exemplary embodiment of the present disclosure.

[0008] FIG. 2 depicts a schematic of the arrangement of test and control sites in the rabbit skin irritation study, according to an exemplary embodiment of the present disclosure.

[0009] FIG. 3 depicts a graph showing the reduction of MRSA in the presence of Formulation 1 in the suspension time-kill procedure, according to an exemplary embodiment of the present disclosure.

[0010] FIG. 4 depicts a graph showing the reduction of T. rubrum in the presence of Formulation 1 in the suspension time-kill procedure, according to an exemplary embodiment of the present disclosure.

[0011] FIG. 5 depicts a data plot showing a reduction in BCC-l/KMC tumor growth after treatment according to the presently disclosed compositions and methods, according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0012] The present disclosure provides compositions and methods for the treatment of skin cancer. It has been unexpectedly discovered that the presently disclosed compositions comprising polyhexamethylene biguanide (PHMB) are effective in the treatment of skin cancer, including cutaneous basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (SCC). The presently disclosed compositions may also be effective in the treatment of precancerous lesions of the skin and to prevent or reduce the recurrence of skin cancer in subjects having previously undergone surgical treatment to remove, reduce, or destroy BCC or SCC.

[0013] According to at least one aspect of the present disclosure, a method of treating skin cancer in a subject is provided. The method may include applying a composition comprising polyhexamethylene biguanide (PHMB) to an area of the skin of the subject in need of treatment. In at least some instances, the skin cancer may be cutaneous basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (SCC). According to one aspect, the composition may be a petrolatum-based composition that includes petrolatum and a pharmaceutically effective amount of PHMB. In such cases, the compositions may include, for example, greater than about 80% by weight petrolatum. The compositions may also include a polar solvent. In some instances, the polar solvent may be water. In other cases, the polar solvent may be ethanol or a mixture of ethanol and water. In certain cases, the PHMB and the polar solvent may be dispersed in the petrolatum in the form of nanodroplets. According to at least one aspect, the petrolatum-based PHMB compositions contain no emulsifier. In some instances, the PHMB may be dissolved in a polar solvent to form a PHMB solution and the PHMB solution dispersed in the petrolatum. In such cases, the PHMB solution may be dispersed in the petrolatum to form a stable suspension such that the PHMB solution does not separate from the petrolatum for at least six months.

[0014] The presently disclosed petrolatum-based PHMB compositions may be prepared by a process that includes: a) dissolving the PHMB in a polar solvent to give a PHMB solution; b) heating the petrolatum to a temperature sufficient to cause the petrolatum to melt to give a melted petrolatum and heating the PHMB solution to a temperature higher than the temperature of the melted petrolatum to give a heated PHMB solution; c) mixing the melted petrolatum and the heated PHMB solution to give a melted mixture; and d) cooling the melted mixture to give the petrolatum-based composition. In some instances, the PHMB solution is heated to a temperature that is about l°C to about 5°C higher than the temperature of the melted petrolatum. According to at least one aspect of the present disclosure, the resultant petrolatum-based PHMB composition does not require an emulsifier to form a stable suspension of PHMB dispersed in the petrolatum. Further, the petrolatum-based PHMB composition prepared according to this process does not require high shear mixing to form a stable suspension of PHMB in petrolatum in the absence of an added emulsifier.

[0015] According to another aspect of the present disclosure, compositions comprising a pharmaceutically acceptable amount of PHMB in a pharmaceutically acceptable carrier are provided. The pharmaceutically acceptable carrier may be, for example, petrolatum, cocoa butter, jojoba oil, olive oil, soybean oil, coconut oil, beeswax, lanolin wax, carnauba wax, stearic acid, or any mixture thereof. Such PHMB compositions may further include, at least in some instances, a polar solvent. The polar solvent may be, for example, water, ethanol, or any mixture of water and ethanol. In some instances, the PHMB and the polar solvent may be dispersed in the pharmaceutically acceptable carrier in the form of nanodroplets.

[0016] The presently disclosed compositions may include less than 1% by weight PHMB, or from about 0.1% to about 1% by weight PHMB, or from about 0.2% to about 0.6% by weight PHMB, or from about 0.3% to about 0.5% by weight PHMB. The presently disclosed compositions may also include a preservative. In some instances, the preservative may be benzalkonium chloride, cetrimide, chlorhexidine, or any combination thereof.

[0017] The presently disclosed composition may be effective in the treatment of precancerous lesions of the skin and to prevent or reduce the recurrence of skin cancer in subjects having previously undergone surgical treatment to remove, reduce, or destroy BCC or SCC. For instance, the presently disclosed compositions may be applied to a portion of a subject’s skin that has previously been surgically treated by excision, curettage, electrodessication, Mohs micrographic surgery, cryotherapy, cryosurgery, radiation therapy, and any combination thereof. In such cases, topical administration of the presently disclosed compositions may be effective in preventing or reducing the recurrence of skin cancer in the treated portion of the subject’s skin.

[0018] According to an aspect of the present disclosure, the presently disclosed compositions may be effective in inhibiting sonic hedgehog signaling in a skin cancer cell of a subject. Accordingly, the present disclosure provides a method of treating skin cancer in a subject that includes inhibiting sonic hedgehog signaling in a skin cancer cell by contacting the skin cancer cell with a therapeutically effective amount of a PHMB composition. As described briefly above, the present disclosure provides for petrolatum-based compositions of PHMB, processes for making petrolatum-based compositions of PHMB, and applications and uses of petrolatum-based compositions of PHMB in the treatment and prevention of skin cancer. PHMB is a polar active ingredient. It has been surprisingly and unexpectedly discovered that PHMB may be dispersed throughout the petrolatum as nanodroplets with the petrolatum serving as a suspension matrix for the polar ingredients. Importantly, petrolatum-based compositions of the present disclosure generally do not contain an emulsifier. As it was discovered by the inventors, not only were emulsifiers not necessary for dispersing cationic biocides, such as PHMB, in the petrolatum, but the structure of the compositions is shelf stable for extended periods of time even under non-ideal conditions. In addition, the compositions exhibit exceptional chemical stability of the cationic biocides, including PHMB, and are capable of delivering an active ingredient over extended periods of time. The novel formulations provide anti-tumor activity against cutaneous carcinomas such as BCC and SCC, are exceptionally gentle, and provide long-lasting therapeutic activity, making the formulations particularly suitable for skin cancer treatments and pre treatments.

[0019] The presently disclosed compositions and methods may include one or more topical anticancer agents in addition to one or more cationic biocides, such as PHMB. The one or more topical anticancer agents may comprise from about 0.5% to about 5% by weight of the composition, or from about 0.5% to about 1.5%, or from about 1.0% to about 5.0%, or from about 2.5% to about 5.0%, by weight of the composition. In at least some instances, the topical anticancer agent may be 5-Fluoro uracil (5-FU), or any prodrug, polymeric form, or derivative thereof. According to at least one aspect of the present disclosure, the presently disclosed compositions may advantageously enhance the skin penetration of the one or more topical anticancer agents and/or enhance the retention of the topical anticancer agent at the target site. The presently disclosed compositions may also deliver the one or more topical anticancer agents to the target site with reduced skin irritation and/or increased patient comfort. Therefore, the presently disclosed compositions may provide for increased patient tolerance and compliance during the delivery of the one or more topical anticancer agents. In at least some instances, the presently disclosed compositions may also exhibit enhanced efficacy and/or bioavailability of the topical anticancer agent at the target site.

I. COMPOSITIONS

[0020] The presently disclosed PHMB compositions include a pharmaceutically effective amount of PHMB in a pharmaceutically acceptable carrier. The pharmaceutically acceptable carrier may be selected from the group consisting of petrolatum, cocoa butter, jojoba oil, olive oil, soybean oil, coconut oil, beeswax, lanolin wax, carnauba wax, stearic acid, and any mixture thereof.

[0021] According to one aspect, the present disclosure provides for compositions having petrolatum as the pharmaceutically acceptable carrier. In such aspects, the PHMB compositions are petrolatum-based. A petrolatum-based composition is made up primarily of petrolatum. The characteristics of a petrolatum-based composition differ from a composition containing only a small amount of petrolatum. In some embodiments, the petrolatum-based composition is greater than about 80% petrolatum. In other embodiments, the petrolatum-based composition is greater than about 81% petrolatum, greater than about 82% petrolatum, greater than about 83% petrolatum, greater than about 84% petrolatum, greater than about 85% petrolatum, greater than about 86% petrolatum, greater than about 87% petrolatum, greater than about 88% petrolatum, greater than about 89% petrolatum, greater than about 90% petrolatum, greater than about 91% petrolatum, greater than about 92% petrolatum, greater than about 93% petrolatum, greater than about 94% petrolatum, greater than about 95% petrolatum, greater than about 96% petrolatum, greater than about 97% petrolatum, greater than about 98% petrolatum, or greater than about 99% petrolatum. The petrolatum is preferably medical grade petrolatum.

[0022] The composition also contains PHMB dispersed throughout the petrolatum. PHMB is the composition ingredient active in treating skin cancer. In addition to PHMB, the compositions may also include other cationic biocides, such as quaternary ammonium compounds, bisbiguanides, and polymeric biguanides. In particular, other cationic biocides that may be included in the compositions may include, but are not limited to, benzalkonium chloride, cetrimide, chlorhexidine, polihexanide biguanide (polihexanide, polyhexamethylene guanide, poly(iminoimidocarbonyl-iminoimidocarbonyl-iminohexamethylene),

poly(hexamethylenebiguanide), polyaminopropyl biguanide) and salts or combinations thereof. In one embodiment, the composition contains a mixture of polihexanide biguanide (PMHB) and benzalkonium chloride (BZK) preservative. The total amount of cationic biocide in the composition generally constitutes less than about 1% by weight of the total composition. In preferred embodiments, the cationic biocide constitutes from about 0.1% to about 0.5% by weight, or more preferably, from about 0.1% to about 0.3% by weight to the total composition.

[0023] The remaining weight of the composition, typically from about 0.1% to about 6% by weight of the petrolatum-based composition, is liquid. In a preferred embodiment, the composition contains about 5% water.

[0024] The PHMB and other cationic biocides that may be used do not react with the pharmaceutically acceptable carrier, such as coconut oil or petrolatum. Instead, the PHMB and other cationic biocides that may be included in the compositions are dispersed in the petrolatum carrier as nanodroplets, and the petrolatum carrier serves as a suspension matrix for the PHMB and other cationic biocides. “Nanodroplet,” as used herein, is an aggregation of PHMB and any cationic biocide molecules in the petrolatum base. The nanodroplets typically contain a small amount of water in addition to the PHMB and other cationic biocides. Nanodroplets in accordance with the present disclosure are shown in FIG. 1. The nanodroplets may vary in size but generally the longest dimension of the nanodroplets measures from about 10 nm to about 10,000 nm. In various embodiments, the nanodroplets range from about 10 nm to about 100 nm, from about 100 nm to about 1000 nm, from about 1000 nm to about 2000 nm, from about 2000 nm to about 3000 nm, from about 3000 nm to about 4000 nm, from about 4000 nm to about 5000 nm, from about 5000 nm to about 6000 nm, from about 6000 nm to about 7000 nm, from about 7000 nm to about 8000 nm, from about 8000 nm to about 9000 nm, from about 9000 nm to about 10,000 nm. The nanodroplets are dispersed through the petrolatum homogeneously.

[0025] Surprisingly, embodiments of the present invention do not require an emulsifier. An emulsifier, as used herein, is an added formulation ingredient used to reduce the tension between hydrophilic and hydrophobic surface ingredients, thereby facilitating the mixture hydrophilic and hydrophobic ingredients. Prior to the present invention, those skilled in the art expected that an emulsifier would be needed to disperse cationic biocides, such as PHMB, which are polar, in a non-polar petrolatum suspension matrix. Where an emulsifier is used, it has a hydrophilic-lipophilic balance (HLB) of less than 10. [0026] The compositions described herein are stable. In one aspect, stability refers to the integrity of the composition as a whole, and in particular, the stability of the nanodroplets in the petrolatum. Under ambient conditions, the petrolatum and the cationic biocides will not separate for greater than two years, meaning that the composition is shelf stable for at least two years. Even under accelerated conditions, such as reduced pressure, the petrolatum and the PHMB and any other cationic biocides do not separate, but rather the PHMB and cationic biocides remain suspended as nanodroplets in the petrolatum. In addition to the stability of the nanodroplets within the composition, the compositions described herein also show exceptional chemical stability for the PHMB and other cationic biocides. The chemical stability stems primarily from the low-temperature manufacturing process described below. The absence of excessive heat conditions in the manufacturing of the compositions improves the chemical stability (resistance to degradation) for the PHMB and other cationic biocides.

[0027] In some embodiments, the petrolatum-based compositions described herein consist essentially of petrolatum, PHMB, and water. In one preferred embodiment, the petrolatum-based compositions consist essentially of petrolatum, benzalkonium chloride, polihexanide biguanide, and water. In alternative embodiments, the petrolatum-based compositions described herein consist of petrolatum, a cationic biocide, and water or consist of petrolatum, benzalkonium chloride, polihexanide biguanide, and water.

[0028] In other embodiments, the petrolatum-based compositions described herein may further comprise a compound that stimulates healing. More specifically, the petrolatum-based compositions described herein may further comprise a compound that stimulates healing for use in intraoperative applications and chronic wound care applications. Non-limiting examples of compounds that stimulate healing include polycaprolactone-tricalcium phosphate (PCL-TCP), collagen, chitosan, cellulose, thrombin, chondroitin sulfate (CS), chondroitin sulfate succinimidyl succinate (CS-NHS), and growth factors such as TGF-alpha, TGF-beta (TGFpi , TGFP2, TGFP3), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), fibroblast growth factor also referred to as keratinocyte growth factor (FGF1, FGF2, FGF4, FGF7), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), connective tissue growth factor (CTGF), activin, interleukin- 1 (IFla, IEIb), TNFa, GM-CSF, or autologous intraoperative biologies such as platelet-rich plasma (PRP) and bone marrow (BM). [0029] In other embodiments, the petrolatum-based compositions described herein may further comprise a dermatologically acceptable carrier. A“dermatologically-acceptable carrier,” as used herein, is a component or components suitable for use in contact with human keratinous tissue without undue toxicity, incompatibility, instability, allergic response, and the like. Where employed, the carrier is inert in the sense of not bringing about a deactivation of the active ingredients, and in the sense of not bringing about any adverse effect on the skin areas to which it is applied. Common dermatological additives are also envisioned for some embodiments. In certain embodiments, a dermatological additive is a whitening agent and/or hemostatic agent.

[0030] Additionally, the compositions may be incorporated in predetermined therapeutically effective amounts into disposables such as wipes, gauze, patches, wraps, bandages, adhesive strips, sponge, cotton swab, glove, sock, wrist bands, fabric, fibers, sutures, medication pad, underwear, tissue, pain-relief gel pack or bed liner and the like. For instance, the composition may be applied to the surface of, or impregnated into disposables.

II. PROCESS FOR MAKING

[0031] The disclosure also provides a method for making the compositions described in Section (I). The process comprises: (a) dissolving PHMB in a solvent to give a PHMB solution; (b) heating the pharmaceutically acceptable carrier to a temperature sufficient to give a melted pharmaceutically acceptable carrier, and heating the PHMB solution to a temperature higher than the temperature of the pharmaceutically acceptable carrier to give a heated PHMB solution; (c) mixing the melted pharmaceutically acceptable carrier and the heated PHMB solution to give a melted mixture; and, (d) cooling the melted mixture to give the pharmaceutically acceptable carrier-based composition. As would be appreciated by one of skill in the art, steps (a) - (d) are conducted sequentially. In at least some instances, the pharmaceutically acceptable carrier is petrolatum. The process for making the presently disclosed compositions will be describe below using petrolatum as an example pharmaceutically acceptable carrier. However, other pharmaceutically acceptable carriers may be used, including coconut oil, cocoa butter, jojoba oil, olive oil, soybean oil, beeswax, lanolin wax, carnauba wax, stearic acid, and any mixture thereof.

[0032] The PHMB as well any other cationic biocide, selected from the group described in Section (I), is first dissolved in a solvent to give a PHMB/cationic biocide solution. Acceptable solvents for the PHMB/cationic biocide solution include water or other solvents. Generally polar solvents are used. The PHMB and any other cationic biocides are typically dissolved in the solvent a concentration ranging from about 0.05% to about 5%. Typically, the amount of solvent used is from about 1:10 to about 1:30 the amount of petrolatum and more preferably is about 1:20 to the amount of petrolatum by volume. The amount of PHMB and other cationic biocides can be calculated by one skilled in the art to provide the desired weight percentage for the final composition.

[0033] Both the PHMB solution and the petrolatum are heated. The heating of these two ingredients can be conducted at the same time or sequentially so long as the melted petrolatum and the heated PHMB solution are at the appropriate temperatures during the mixing step. Petrolatum is a solid that melts at approximately 37°C. As such, petrolatum may be heated to any temperature at or above 37°C. For instance, the petrolatum may be heated to a temperature ranging from about 37°C to about 45°C, from about 40°C to about 50°C, from about

45°C to about 55°C, from about 50°C to about 60°C, from about 55°C to about 65°C, from about

60°C to about 70°C, from about 65°C to about 75°C, from about 70°C to about 80°C, from about

75°C to about 85°C, from about 80°C to about 90°C, from about 85°C to about 95°C, or from about 90°C to about l00°C or more. Higher temperatures may also be envisioned. Preferably, the petrolatum is heated to a temperature ranging from about 37°C to about 55°C, more preferably to a temperature ranging from about 40°C to about 50°C. Heat may be provided to the petrolatum by any method known in the art, but a water bath or low temperature hot plate are preferred.

[0034] The PHMB solution is heated to a temperature above the temperature of the melted petrolatum. Any temperature above the temperature of the melted petrolatum may be used in a method of the present disclosure, provided that the heat does not cause excessive degradation of an active ingredient such as PHMB, or excessive evaporation of the active ingredient or polar solvent. For instance, the PHMB solution may be heated to a temperature that is about l°C to about l0°C, about 5°C to about l5°C, about l0°C to about 20°C, about l5°C to about 25°C, about 20°C to about 30°C, about 25°C to about 35°C, about 30°C to about 40°C, about 35°C to about 45°C, about 40°C to about 50°C, about 45°C to about 55°C, about 50°C to about 60°C or about 65 °C or about 75°C higher than the temperature of the melted petrolatum. Higher temperatures may also be envisioned. Preferably, the PHMB solution is heated to a temperature that is about l°C to about l0°C higher than the temperature of the melted petrolatum. In another embodiment, the PHMB solution is heated to a temperature that is about l°C to about 5°C higher than the melted petrolatum. In still other embodiments, the PHMB solution is heated to a temperature that is about l°C, 2°C, 3°C, 4°C, or 5°C above the temperature of the melted petrolatum. Again, the heating can be provided by any means known in the art but is preferably provided by a water bath or low temperature hot plate.

[0035] Once both the petrolatum and the PHMB solution are heated as described above, the melted petrolatum and the heated PHMB solution are mixed to give a melted mixture containing petrolatum and the heated PHMB solution. The mixing can be accomplished by a variety of methods including homogenization, acoustic mixing, and high RPM mixing. Depending on the batch size, the size of the mixer, and the type of mixing, the mixing may be conducted for several minutes or more. When mixed in accordance with the parameters disclosed above, the melted petrolatum and the heated PHMB solution fuse in the melted mixture.

[0036] After the melted petrolatum and the heated PHMB solution have fused they are allowed to cool and solidify into the composition described more fully in Section (I) (“the final composition”). Cooling may be achieved by reducing the amount of heat provided to the melted mixture, or cooling may be achieved passively under conditions where no heating is added. In some embodiments, cooling is controlled so that the temperature of the melting mixture is gradually lowered to ambient temperatures. The product is preferably packaged a few degrees above its solidification point so that the packaging can be filled by pouring the melted mixture. The composition preferably solidifies to the final composition in the package. The package is sealed after this solidification.

[0037] The process may be conducted with two or more cationic biocides. The cationic biocides may be dissolved in solvent separately or may be dissolved in the same solvent. Addition of additional cationic biocides does not change the process steps above.

[0038] In at least some instances, the compositions may include one or more topical anticancer agent, such as 5-Fluoro uracil (5-FU), or any prodrug, polymeric form, or derivative thereof. In such instances, the topical anticancer agent may be added to the PHMB solution or PHMB/cationic biocide solution prior to heating and mixing with the petrolatum or pharmaceutically acceptable carrier. In other instances, the topical anticancer agent may be added directly to the heated petrolatum or pharmaceutically acceptable carrier prior to mixing with the heated PHMB solution. In still other cases, the topical anticancer agent may be added to the final pharmaceutically acceptable carrier-based or petrolatum-based composition either while still warm or cooled.

III. METHODS OF USE

[0039] In another aspect, the invention encompasses a method of preventing or treating skin cancer in a subject using the compositions described herein.

[0040] The compositions may be applied topically to a subject in need. Subjects in need may be those having cancer, including subjects having cutaneous basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (SCC). Subjects in need may also be subjects at risk for recurrence of skin cancer following surgical treatment to remove or destroy cancer cells in a portion of their skin. For instance, the presently disclosed compositions may be applied the skin of a subject, or portion thereof, following excision, curettage, electrodessication, Mohs micrographic surgery, cryotherapy, cryosurgery, radiation therapy, and any combination thereof, to remove or destroy cancer cells at one or more sites on the subject’s skin. The subject is preferably human but the composition may also be useful in animals, particularly mammals, for example domestic animals, livestock, or other types of animals.

[0041] Typically, the composition is applied to the skin of the subject. Application to the skin includes application to a site having skin cancer, such as a cancerous lesion,, suspected of having skin cancer, or at risk for recurrence of skin cancer. The presently disclosed compositions may also be applied to precancerous lesions of the skin. The composition may also be used post-operatively as a topical dressing to prevent or reduce the recurrence of cancer at a surgical treatment site. As used herein, the terms“applied to the skin” or“applying to the skin,” in all their forms, as used throughout this disclosure in reference to applying the presently disclosed compositions to the skin of a subject, refers to all modes of administration of the compositions to the skin of a patient including topical administration of the compositions directly to the skin of a subject or causing contact between the compositions and the skin of a patient through, for instance, a wrap, gauze, or bandage impregnated or containing the presently disclosed compositions.

[0042] The amount of composition applied in the methods described herein can and will vary depending on the condition being treated and the severity of that condition. Generally, the amount used is sufficient to cover the affected skin area with a thin layer of the composition. The composition is applied directly to the skin. In some embodiments, the composition is spread so that it forms a thin layer over the treatment area. In other embodiments, the composition is spread by a melting action that occurs as the warmth of the patient’s skin melts the petrolatum or pharmaceutically acceptable carrier. The composition may be covered with a bandage after application. The compositions may also be impregnated into a bandage or other material that is applied to the treatment area.

[0043] The composition when applied to the skin is non-irritant and no n-cyto toxic. These properties allow the composition to be used on sensitive areas of the skin. These characteristics also allow for use to treat or prevent skin cancer over a long period, such as for example 2 weeks, 4 weeks, 6 weeks, 8 weeks, or longer without irritation to the treated area. It will be recognized however, that the compositions may be used for shorter periods of time if necessary.

[0044] The compositions are also capable of extended release of the PHMB to the area of application.“Extended release” as used herein means that the compositions release PHMB to the application site over a period of time extending past twelve hours. The time over which the extended release is provided is variable depending on the amount of the composition that is applied, but in general, the release of PHMB is extended beyond the initial application and PHMB has been shown to be released for up to 1 week. This extended release allows the composition to be applied less frequently and improves patient compliance with the treatment.

[0045] The compositions of the present disclosure also offer kinetic release when applied to the skin. Kinetic release means that PHMB is released to the treatment area more rapidly when the treatment area is hotter.

EXAMPLES

[0046] The following examples are included to demonstrate preferred embodiments of the disclosure. It should be appreciated by those of skill in the art that the techniques disclosed in the examples that follow represent techniques discovered by the inventors to function well in the practice of the disclosure, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the disclosure. Example 1. Exemplary Formulation Process

[0047] “Formulation 1” (FIG.l) was prepared by adding 2540.3 pounds of white petrolatum to a tank that has been cleaned and sterilized in accordance with SOP protocol. In the tank was used to heat the petrolatum to 1 l0°C to 1 l3°F to melt the petrolatum. In a separate clean and sanitized container 133.70 pounds of water and the desired amount of BZK and PHMB were added and heated to l22°F. When both phases were at temperature, the solution phase was slowly added to the petrolatum with mixing. The heat was decreased slowly to 96 to l04°F. The product was tested for quality control and transferred to polypropylene drums. The resulting composition was shiny and white to slightly yellow in appearance. Specific gravity at 25°C matches specification when it is from 0.830-0.910. Viscosity at @ 25° C TF @ 10 rpm matches specification when it is from about 225,000-300,000 cps. The final formulation contained the following ingredients by weight percent: 95% petrolatum, 0.13% BZK, 0.2% PHMB, and 4.67% water.

Example 2. Skin Sensitization Evaluation

[0048] A study was conducted on the formulation of Example 1, referred to herein as “Formulation 1” to assess skin sensitization. Patches comprising Formulation 1 were affixed directly to the skin of 53 human study participants representing an age range from 18-63 and five skin types. Table 1 presents the participant demographics. Patches remained in place for 48 hours after the first application. Participants were instructed not to remove the patches prior to their 48 hour scheduled visit. Thereafter, the subjects were instructed to remove patches for 24 hours. This procedure was repeated until a series of nine consecutive, 24 hour exposures had been made three times per week for three consecutive weeks. Test sites were evaluated by trained personnel. Following a 10-14 day rest period, a retest/challenge dose was applied once to a previously unexposed test site. Test sites were evaluated by trained personnel 48 and 96 hours after application. The sites were scored based on the International Contact Dermatitis Research Group scoring scale (Rietschel, Fowler, Ed., Fisher’s Contact Dermatitis (fourth ed.). Baltimore, Williams & Wilkins, 1995) as presented in Table 2.

[0049] No adverse reactions of any kind were reported during the course of study. Accordingly, Formulation 1 gives no identifiable signs or symptoms of primary irritation or sensitization (contact allergy).

Example 3. Antimicrobial Efficiency Testing.

[0050] Antimicrobial efficacy testing was conducted according to USP 51. Five microbes were tested. Each organism was inoculated at an inoculum level of 1 x 10⁶ colony forming units (CFU) per gram for bacteria or 1 x 10⁵ CFU per gram for yeast and mold. The inoculated samples were then stored at 20-25°C for 28 days. The population of each microorganism was determined by plate counting at Day 2, 7, 14, 21, and 28. The plate counts were performed at a 1:10 initial dilution using Modified Letheen Broth as the diluent and plated onto Tryptic Soy and Sabouraud Dextrose agar.

[0051] A single application of Formulation 1 gave 100% elimination from day 2 to day 28 for all microbes tested (Table 3). Given the 100% elimination, there was a 4 log reduction in the yeast/mold species and a 5 log reduction in the bacterial species (Table 4). Table 5 is a positive control indicating that the method used recovers 80-100% of the microbe in the absence of Formulation 1. Accordingly, the microbes present in the test sample were eliminated under the tested conditions. The results illustrate the broad spectrum of activity for Formulation 1.

Example 4: Cytotoxicity Evaluation.

[0052] The study was conducted to assess the biological reactivity of mammalian cells (grown in culture) to the agar-diffusible elements of Formulation 1.

[0053] The samples to be evaluated for cytotoxicity include test product comprising Formulation 1, Amber latex tubing as a positive control, and HDPE sheet stock as a negative control. The samples were sized to have no less than 100 mm of contact surface and provide coverage of approximately 10% of the test dish. The dimensions of the test product comprising Formulation 1 were 1.1 x 1.1-1.2 cm; the dimensions of the positive control were 1.0 x 2.55-2.7 cm; and the dimensions of the negative control were 1.15 x 1.0- 1.2 cm. The manipulation of the samples was performed aseptically.

[0054] Prior to exposure to the samples, the L929 Mouse Fibroblast cells were subcultured in Minimum Essential Medium (MEM) with 10% Fetal Bovine Serum (FBS) to achieve a confluency of approximately 80 ± 10% at the time of exposure. The cells were examined for normal morphology and the absence of contamination. Once the cells met the acceptance criteria for use, individual dishes were numbered in triplicate to represent the controls and the test product comprising Formulation 1.

[0055] On the day of testing, the subculture media was carefully removed from each test dish and replaced with a 2 mL aliquot of the 1:1 overlay medium (in equal parts of 2x Minimum Essential Medium (with 2% Fetal Bovine Serum) and Agar Noble). After allowing the overlay medium to solidify, a single test product comprising Formulation 1 or control sample was placed in the center of each dish (in contact with the agar surface). Triplicate cultures were prepared for each test product comprising Formulation 1 and positive and negative controls (one sample per dish). When the test product comprising Formulation 1 or positive/negative control has only one face designated for patient-contact, that“side” of the sample was directed toward the agar. The test dishes, along with 3 dishes with overlay medium only (Monolayer Negative Controls), were then placed in the 37°C / 5% C0₂ incubator to initiate the exposure interval.

[0056] The dishes were incubated for 24 hours and then microscopically examined for an indication of cellular response. A preliminary microscopic examination of the cells was made prior to staining and before the control and test product comprising Formulation 1 were removed from the agar layer. The cells were then stained with a fresh working Neutral Red Solution to facilitate response grading. The test product comprising Formulation 1 and control samples were removed from the dishes at this time. The stained cells were then fixed by the addition of buffered formalin. Following fixation, the agar overall was removed from each dish. Following staining, the cellular responses were then evaluated microscopically and macro scopically (by examining the dishes against a white surface) and the results were recorded.

[0057] For the control samples to be deemed valid, the negative controls may be no greater than Grade 0 and the positive control may be no less than Grade 3. For the test product comprising Formulation 1, a Grade of 0, 1 (slight) or 2 (mild) indicates the test product comprising Formulation 1“meets” the assay acceptance criteria and a Grade of 3 (moderate) or 4 (severe) indicates the test product comprising Formulation 1 does not meet the assay acceptance criteria. Table 6 depicts the Grading guidelines.

[0058] Table 7 depicts the results of the study. The assay controls met the acceptance criteria for a valid assay. All negative controls responses were no greater than Grade 0 and the positive control response were not less than Grade 3. The responses observed for the test product comprising Formulation 1 were interpreted according to the current USP guidelines. The Grade 1 response from the test product comprising Formulation 1 is considered to be "non-cytotoxic" (i.e. meets ISO test acceptance requirements of no more than Grade 2 reactivity). Accordingly, Formulation 1 does not damage mammalian cells.

Example 5: Rabbit Skin Irritation

[0059] The study was conducted to assess the irritating potential of Formulation 1 to produce dermal irritation.

[0060] Within 24 hours to 4 hours before test application, the backs of female albino New Zealand White rabbits were clipped free of hair, exposing 2 test and 2 control areas on each side of the spine with a size of approximately 15 cm x 15 cm. The two test sites are located on the left cranial section and the right caudal section of the dorsal region. The two control sites are located on the left caudal and right cranial section of the dorsal region. FIG. 2 depicts the arrangement of test and control sites. The exposed skin is wiped with alcohol and dried. Rabbits of acceptable skin quality were selected and used for testing.

[0061] A 25 x 25 mm gauze patch saturated with 0.5 mL (liquid) or 0.5 g (powder) of Formulation 1 is applied to the clipped test sites. A 25 x 25 mm gauze patch saturated with 0.5 mL of 0.9% NaCl is used for the control and applied to the clipped control sites. The patches are secured using hypoallergenic, waterproof, surgical tape over the test and control sites. The animal’s trunk is securely wrapped so as to maintain the position of the patches. Patches are left applied for a minimum of four hours.

[0062] After patch removal, the test and control sites were then scored for erythema and edema at 1, 24, 48 and 72 hours after patch removal. Only the 24, 48, and 72 hour observations were scored and used for calculations. The criteria for scoring is presented in Table 8. If no response was expected, testing was conducted using three animals per test article. If irritation was anticipated, one animal was tested initially. If the first animal received a score of 2 or less for either erythema or edema, 2 additional rabbits were used to conclude the test.

[0063] For each animal and each extract, when applicable, the scores for the test article comprising Formulation 1 for erythema and edema at each time were added. This total was divided by the total number of observations. The same was done for the control sites. The control result was subtracted from the test results to give the irritation index for each animal. These scores for each animal were added and divided by the total number of animals to give the Primary Irritation Index. The Primary Irritation Index is depicted in Table 9. For any response, the Maximum Irritation Response, the time of onset of the response and the time of maximum response was recorded.

[0064] The results indicated that the skin reactions for both the test article comprising Formulation 1 and control samples were not significant. That data is presented in Table 10 below. Accordingly, the Formulation 1 is non-irritating.

[0065] To positively validate the test, 10% sodium dodecyl sulfate (SDS), which is a known dermal irritant, in petroleum jelly was applied to a 2.5 cm x 2.5 cm gauze patch. As a negative control, 0.5 mL of 0.9% NaCl was applied to a 2.5 cm x 2.5 cm gauze patch. A Primary Irritation Index in the moderate to severe range is considered a positive result. The test system and methods utilized were the same as described above. Table 11 presents the results validating the study.

Example 6. Suspension Time-Kill Procedure for MRSA, T. rubrum, and Staphylococcus epidermidis.

[0066] A study was conducted to evaluate the changes in the population of MRSA in an antimicrobial liquid suspension comprising Formulation 1. Methicillin-resistant Staphylococcus aureus (MRSA) is a Gram-positive, cocci shaped, aerobe which is resistant to the penicillin-derivative antibiotic methicillin. MRSA can cause troublesome infections, and their rapid reproduction and resistance to antibiotics makes them more difficult to treat. MRSA bacteria are resistant to drying and can therefore survive on surfaces and fabrics for an extended period of time and therefore makes this bacteria an excellent representative for antimicrobial efficacy testing on surfaces.

[0067] To conduct the study, MRSA was prepared in liquid culture medium (Letheen Broth). The suspension of MRSA was standardized by dilution to 10⁶ in a buffered saline solution. Formulation 1 and control substance (PBS) were dispensed in identical volumes to sterile vessels. Independently, Formulation 1 and control substance were each inoculated with MRSA, then mixed and incubated. Control substances were immediately harvested and represented the concentration present at the start at the test (i.e. time zero). At the conclusion of contact time, a volume of the liquid test product was harvested and chemically neutralized. Dilutions of the neutralized test solution were assayed using appropriate growth media to determine the surviving MRSA at the respective contact times. Reductions in MRSA were calculated by comparing initial microbial concentrations to final microbial concentrations. Table 12 and FIG. 3 present the results of the study.

[0068] The same study was conducted with Trichophyton rubrum. T. rubrum is a fungus which belongs to the dermatophyte group. Dermatophytes commonly cause skin disease in animals and humans. T. rubrum is anthropophilic, meaning it preferentially infects humans over animals. This parasite is the most common cause of fungal infection of the fingernail and Athlete’s foot, this specific strain was isolated from a human toenail. In the laboratory, visible colonies can be observed after approximately 4-5 days and are fluffy and white in appearance. T. rubrum is a popular test microorganism for fungicidal testing, especially for products intended for use in environments where skin infections can occurs and spread rapidly such as locker rooms and schools.

[0069] To conduct the study, T. rubrum was prepared on agar (potato dextrose agar). The T. rubrum was resuspended and inoculated at a dilution of -10⁶ into vessels containing Formulation 1 and control substance (PBS). Control substances were immediately harvested and represented the concentration present at the start at the test (i.e. time zero). At the conclusion of contact time (2 or 10 minutes), a volume of the liquid test product was harvested and chemically neutralized. Dilutions of the neutralized test solution were assayed using appropriate growth media to determine the surviving T. rubrum at the respective contact times. Reductions in T. rubrum were calculated by comparing initial microbial concentrations to final microbial concentrations. Table 13 and FIG. 4 present the results of the study.

[0070] The same study was conducted with Staphylococcus epidermidis. Gram-positive organisms currently account for 50-60% of nosocomial bacteremic events. Staphylococcus epidermidis is the most common gram-positive organism isolated from blood (30% of isolates) and accounts for the majority of infections that are associated with intravascular catheters, as it is capable of forming antibiotic resistant biofilms on plastic surfaces.

[0071] In an effort to further explore the preventative benefits of Formulation 1 in preventing catheter related and hospital acquired infections, a suspension time kill assay as described above was initiated on this often under-discussed organism. A nearly 7 log kill over 24 hours was observed, which represents a typical change interval for intravenous catheter dressings (Table 14).

Example 7. Stability.

[0072] Formula I as packaged in tubes was subjected to an accelerated stability study. Formula I was placed sideways in a 40°C ± 2°C / 75% ± 5% relative humidity (RH) storage chamber for different intervals to yield a period of three months. The product was assessed for physical and analytical characteristics. When stored at 40°C ± 2°C / 75% ± 5% (RH) benzyl alkonium chloride was stable as shown in Table 15.

[0073] Additionally, the product met specification for appearance, odor, specific gravity, viscosity and package compatibility at all time points tested.

[0074] Formula I was also tested under for microbial counts at 40°C ± 2°C / 75%

± 5% were as shown below. The results are shown in Table 16.

[0075] Additionally, the product met specification for appearance, odor, specific gravity, viscosity and package compatibility at all time-points tested when under standard conditions for over nine months.

Example 8. Formulation Example 1

[0076] A petrolatum-based composition in accordance with the present disclosure was prepared by mixing lOOOcc of water containing 2% by weight PHMB and 0.13% by weight BZK. The water solution was heated to 40°C and was then added to 19,000 cc of petrolatum at about 45°C to give 20,000cc of a petrolatum-based composition containing BZK and PHMB.

Example 9. Formulation Example 2

[0077] A petrolatum-based composition in accordance with the present disclosure was prepared by mixing lOOOcc of water containing 2% by weight PHMB. This solution was then added to 20,000 cc of petrolatum to give 2l,000cc of a petrolatum-based composition containing PHMB.

Example 10. Formulation Example 3

[0078] A petrolatum-based composition in accordance with the present disclosure was prepared by mixing PHMB, BZK and water to form a PHMB solution that contained 10% by weight PHMB, 0.13% by weight BZK, and 89.87% by weight water. The PHMB solution was heated to a temperature from about 1°C to about 5°C higher than the temperature of the melted petrolatum and mixed to form a composition comprising 95% by weight petrolatum, 4.4935% by weight water, 0.5% by weight PHMB, and 0.0065% by weight BZK.

Example 11. Effect of Formulation Example 3 on Cutaneous Basal Cell Carcinoma (BCC)

[0079] The effect of the composition of Formulation Example 3 (Example 10) on cutaneous BCC was studied in an in vivo xenograft study using a BCC-l/KMC xenograft model. Fifty-two (52) NET(NCr)-Foxnlnu nude mice (9-10 weeks old) were acquired and acclimatized for 1-week in accordance with IACETC guidelines. Xenotransplantation was performed on the fifty-two (52) animals resulting in the generation of forty (40) tumor-bearing animals (-80-85% tumor take). The study design, including administration of the test articles and the animal numbers in each study group, is shown in Table 17.

[0080] BCC-l/KMC cancer cells were maintained in vitro as a monolayer culture in RPMI-1640 medium (ATCC) supplemented with 10% fetal bovine serum at 37°C in an atmosphere of 5% C0₂ in air. The tumor cells were routinely subcultured twice weekly by trypsin-EDTA treatment (0.25% Trypsin-EDTA). Cells were passaged at 1:5 split ratio at 80- 90% confluency. The cells in an exponential growth phase were harvested and counted for tumor inoculation. Cells were analyzed by GETAVA PCA flow cytometry for cell count and cell viability (99%) prior to xenotransplantation. Fifty-two (52) million cells were generated.

[0081] Each mouse was inoculated subcutaneously at the flank region with BCC- l/KMC cancer cells (1 x 10⁶) in 0.1 mL of lxPBS mixed with Matrigel (1:1) for tumor development (following 50% Matrigel protocol per Altogen Labs SOP 6.012). Measurable tumors (100-150 cu mm) were developed five days after xenotransplantation. Forty (40) animals with approximately 100-150 mm tumors were selected for follow up experiment and randomly placed in Groups 1-3. The tumor cell inoculation is denoted as Day 0.

[0082] Before grouping and treatment, all animals were weighted and the tumor volumes were confirmed (approximately 100-150 mm ) using electronic caliper. Since the tumor volume can affect the effectiveness of any given treatment, mice were assigned into groups using randomized block design as following: first, the experimental animals were divided into homogeneous blocks based on their tumor volume; secondly, within each block, randomization of experimental animals to different groups was conducted. By using randomized block design to assign experimental animals, it was ensured that each animal had the same probability of being assigned to any given treatment group thereby minimizing systematic error.

[0083] The composition of Formulation Example 3 (Example 10) was administered to the animals in Group 2. Fluorouracil cream 0.5% (Dermik Laboratories, Inc., Bridgewater, New Jersey) was used as a positive control and administered to the animals in Group 3. The composition of Formulation Example 3 and the positive control formulation were both administered topically twice a day. After tumor cells inoculation, the animals were checked daily for morbidity and mortality. At the time of routine monitoring, the animals were checked for any adverse effects of tumor growth and treatments on normal behavior such as mobility, visual estimation of food and water consumption, body weight gain/loss, eye/hair matting and any other abnormal effects. Death and observed clinical signs were recorded per Altogen Labs IACUC.

[0084] Tumor volumes were measured three times a week in two dimensions using an electronic caliper, and the volume was expressed in mm using the formula: V = 0.5 a x b where a and b are the long and short diameters of the tumor, respectively. Dosing and tumor volume measurement procedures were conducted in a Laminar Flow Cabinet. The mean and the standard error of the mean (SEM) were determined for the tumor volume of each group at each time point. Statistical analysis of the difference in tumor volume among the groups and the analysis of drug interaction was conducted on the data obtained after the final dose. No animal death was observed in the study and no animals were observed to have >20% body weight loss (BWL) within the study period.

[0085] The results of the study are shown in FIG. 5. As depicted in FIG. 5, the composition of Formulation Example 3 (Example 10) (Group 2) was effective at delaying subcutaneous BCC-l/KMC tumor growth as compared to both the untreated animal control (Group 1) and the Fluorouracil cream 0.5% treated positive control (Group 3). In particular, animals treated with the presently disclosed composition exhibited reduced average tumor volume showing that the presently disclosed compositions are effective in the treatment of skin cancer when applied topically to skin cancer cells.

Example 12. Topical Administration of PHMB Compositions Improves Clinical Outcomes in Subjects Having Skin Cancer

[0086] The effect of topical administration of the presently disclosed PHMB compositions in the treatment of human subjects having skin cancer will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed PHMB compositions including, but not limited to, Formulation Examples 1-3. In particular, the PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by the skin cancer. Subjects receiving treatment using the presently disclosed PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

Example 13. Topical Administration of PHMB Compositions Improves Clinical Outcomes in Subjects Having Cutaneous Basal Cell Carcinoma (BCC)

[0087] The effect of topical administration of the presently disclosed PHMB compositions in the treatment of human subjects having cutaneous basal cell carcinoma (BCC) will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed PHMB compositions including, but not limited to, Formulation Examples 1-3. In particular, the PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by cutaneous basal cell carcinoma (BCC). Subjects receiving treatment using the presently disclosed PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

Example 14. Topical Administration of PHMB Compositions Improves Clinical Outcomes in Subjects Having Cutaneous Squamous Cell Carcinoma (SCC)

[0088] The effect of topical administration of the presently disclosed PHMB compositions in the treatment of human subjects having cutaneous squamous cell carcinoma (SCC) will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed PHMB compositions including, but not limited to, Formulation Examples 1-3. In particular, the PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by cutaneous squamous cell carcinoma (SCC). Subjects receiving treatment using the presently disclosed PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

Example 15. Topical Administration of PHMB Compositions Inhibits Sonic Hedgehog Signaling in Skin Cancer Cells

[0089] The effect of topical administration of the presently disclosed PHMB compositions in the treatment of human subjects having skin cancer cells characterized by uncontrolled activation of the hedgehog signal pathway will be studied using a randomized, double-blind clinical study. In particular, the subjects may be diagnosed with cutaneous basal cell carcinoma (BCC). During the clinical study, a group of human subjects will be topically administered one of the presently disclosed PHMB compositions including, but not limited to, Formulation Examples 1-3. In particular, the PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by the skin cells having uncontrolled activation of the hedgehog signal pathway. Subjects receiving treatment using the presently disclosed PHMB compositions are expected to have improved standard clinical outcomes, particularly a reduction or inhibition of sonic hedgehog signaling in cancer cells of the skin, such as basal cells. Subjects receiving treatment according to the presently disclosed methods and techniques are also expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

Example 16. Topical Administration of PHMB Compositions Improves Clinical Outcomes in Subjects Having Precancerous Lesions of the Skin

[0090] The effect of topical administration of the presently disclosed PHMB compositions in the treatment of human subjects having precancerous lesions of the skin will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed PHMB compositions including, but not limited to, Formulation Examples 1-3. In particular, the PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by precancerous lesions. Subjects receiving treatment using the presently disclosed PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit a reduced rate of occurrence of skin cancer in the portion of the skin receiving treatment. In subjects that develop skin cancer, the subject is expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

Example 17. Topical Administration of PHMB Compositions Improves Clinical Outcomes in Subjects Having Previously Undergone Surgical Treatment to Remove or Destroy Skin Cancer

[0091] The effect of topical administration of the presently disclosed PHMB compositions in the treatment of human subjects having previously received surgical treatment to remove or destroy skin cancer cells will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed PHMB compositions including, but not limited to, Formulation Examples 1-3. In particular, the PHMB composition will be applied to a portion of the skin of a subject that has previously received surgical treatment to remove or destroy skin cancer cells. For example, the portion of the skin of the subject may have undergone excision, curettage, electrodessication, Mohs micrographic surgery, cryotherapy, cryosurgery, radiation therapy, or any combination thereof. Subjects receiving treatment using the presently disclosed PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit a reduced rate of recurrence of skin cancer in the portion of the skin receiving treatment. In subjects that do develop skin cancer, the subject is expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

Example 18. Formulation Example 4 - Petrolatum-Based Topical Anticancer Agent PHMB Composition

[0092] “Formulation 4” was prepared in accordance with the present disclosure by mixing PHMB, 5-Fluoro uracil (5-FU), and water to form a PHMB solution. The PHMB solution was heated to a temperature from about l°C to about 5°C higher than the temperature of the melted petrolatum and mixed to form a composition comprising 95% by weight petrolatum, 4% by weight water, 0.5% by weight PHMB, and 0.5% by weight 5-Fluoro uracil (5-FU).

Example 19. Formulation Example 5 - Coconut Oil-Based Topical Anticancer Agent PHMB Composition

[0093] “Formulation 5” was prepared in accordance with the present disclosure by mixing PHMB, 5-Fluoro uracil (5-FU), and water to form a PHMB solution. The PHMB solution was heated to a temperature from about l°C to about 5°C higher than the temperature of the melted coconut oil and mixed to form a composition comprising 95% by weight coconut oil, 4% by weight water, 0.5% by weight PHMB, and 0.5% by weight 5-Fluoro uracil (5-FU). Example 20. Topical Administration of Topical Anticancer Agent PHMB Compositions Improves Clinical Outcomes in Subjects Having Skin Cancer

[0094] The effect of topical administration of the presently disclosed topical anticancer agent PHMB compositions in the treatment of human subjects having skin cancer will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed topical anticancer agent PHMB compositions including, but not limited to, Formulation Examples 4-5. In particular, the topical anticancer agent PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by the skin cancer. Subjects receiving treatment using the presently disclosed topical anticancer agent PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

[0095] Additionally, it is expected that the topical anticancer agent PHMB composition will enhance the skin penetration of the topical anticancer agent, (e.g., 5- Fluorouracil (5-FU)) and/or enhance the retention of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will exhibit enhanced efficacy and/or bioavailability of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will deliver the one or more topical anticancer agents to the target site with reduced skin irritation and/or increased patient comfort as compared with conventional topical anticancer agent compositions. Therefore, it is expected that topical anticancer agent PHMB compositions will be well-tolerated by the patients and result in enhanced patient compliance throughout treatment. In some instances, the administration of the topical anticancer agent PHMB compositions will result in greater improvement in one or more of the above clinical outcomes than administration of formulations comprising only PHMB (e.g., Formulation Examples 1-3) and formulations comprising the topical anticancer agent alone, thereby indicating a synergistic effect between the anticancer activity of PHMB and the topical anticancer agent (e.g., 5-Fluoro uracil (5-FU)) when formulated according to the present disclosure.

Example 21. Topical Administration of Topical Anticancer Agent PHMB Compositions Improves Clinical Outcomes in Subjects Having Cutaneous Basal Cell Carcinoma (BCC)

[0096] The effect of topical administration of the presently disclosed topical anticancer agent PHMB compositions in the treatment of human subjects having cutaneous basal cell carcinoma (BCC) will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed topical anticancer agent PHMB compositions including, but not limited to, Formulation Examples 4-5. In particular, the topical anticancer agent PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by cutaneous basal cell carcinoma (BCC). Subjects receiving treatment using the presently disclosed topical anticancer agent PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

[0097] Additionally, it is expected that the topical anticancer agent PHMB composition will enhance the skin penetration of the topical anticancer agent, (e.g., 5- Fluorouracil (5-FU)) and/or enhance the retention of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will exhibit enhanced efficacy and/or bioavailability of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will deliver the one or more topical anticancer agents to the target site with reduced skin irritation and/or increased patient comfort as compared with conventional topical anticancer agent compositions. Therefore, it is expected that topical anticancer agent PHMB compositions will be well-tolerated by the patients and result in enhanced patient compliance throughout treatment. In some instances, the administration of the topical anticancer agent PHMB compositions will result in greater improvement in one or more of the above clinical outcomes than administration of formulations comprising only PHMB (e.g., Formulation Examples 1-3) and formulations comprising the topical anticancer agent alone, thereby indicating a synergistic effect between the anticancer activity of PHMB and the topical anticancer agent (e.g., 5-Fluoro uracil (5-FU)) when formulated according to the present disclosure.

Example 22. Topical Administration of Topical Anticancer Agent PHMB Compositions Improves Clinical Outcomes in Subjects Having Cutaneous Squamous Cell Carcinoma (SCC)

[0098] The effect of topical administration of the presently disclosed topical anticancer agent PHMB compositions in the treatment of human subjects having cutaneous squamous cell carcinoma (SCC) will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed topical anticancer agent PHMB compositions including, but not limited to, Formulation Examples 4-5. In particular, the topical anticancer agent PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by cutaneous squamous cell carcinoma (SCC). Subjects receiving treatment using the presently disclosed topical anticancer agent PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

[0099] Additionally, it is expected that the topical anticancer agent PHMB composition will enhance the skin penetration of the topical anticancer agent, (e.g., 5- Fluorouracil (5-FU)) and/or enhance the retention of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will exhibit enhanced efficacy and/or bioavailability of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will deliver the one or more topical anticancer agents to the target site with reduced skin irritation and/or increased patient comfort as compared with conventional topical anticancer agent compositions. Therefore, it is expected that topical anticancer agent PHMB compositions will be well-tolerated by the patients and result in enhanced patient compliance throughout treatment. In some instances, the administration of the topical anticancer agent PHMB compositions will result in greater improvement in one or more of the above clinical outcomes than administration of formulations comprising only PHMB ( e.g ., Formulation Examples 1-3) and formulations comprising the topical anticancer agent alone, thereby indicating a synergistic effect between the anticancer activity of PHMB and the topical anticancer agent (e.g., 5-Fluoro uracil (5-FU)) when formulated according to the present disclosure.

Example 23. Topical Administration of Topical Anticancer Agent PHMB Compositions Inhibits Sonic Hedgehog Signaling in Skin Cancer Cells

[00100] The effect of topical administration of the presently disclosed topical anticancer agent PHMB compositions in the treatment of human subjects having skin cancer cells characterized by uncontrolled activation of the hedgehog signal pathway will be studied using a randomized, double-blind clinical study. In particular, the subjects may be diagnosed with cutaneous basal cell carcinoma (BCC). During the clinical study, a group of human subjects will be topically administered one of the presently disclosed topical anticancer agent PHMB compositions including, but not limited to, Formulation Examples 4-5. In particular, the topical anticancer agent PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by the skin cells having uncontrolled activation of the hedgehog signal pathway. Subjects receiving treatment using the presently disclosed topical anticancer agent PHMB compositions are expected to have improved standard clinical outcomes, particularly a reduction or inhibition of sonic hedgehog signaling in cancer cells of the skin, such as basal cells. Subjects receiving treatment according to the presently disclosed methods and techniques are also expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

[00101] Additionally, it is expected that the topical anticancer agent PHMB composition will enhance the skin penetration of the topical anticancer agent, (e.g., 5- Fluorouracil (5-FU)) and/or enhance the retention of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will exhibit enhanced efficacy and/or bioavailability of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will deliver the one or more topical anticancer agents to the target site with reduced skin irritation and/or increased patient comfort as compared with conventional topical anticancer agent compositions. Therefore, it is expected that topical anticancer agent PHMB compositions will be well-tolerated by the patients and result in enhanced patient compliance throughout treatment. In some instances, the administration of the topical anticancer agent PHMB compositions will result in greater improvement in one or more of the above clinical outcomes than administration of formulations comprising only PHMB ( e.g ., Formulation Examples 1-3) and formulations comprising the topical anticancer agent alone, thereby indicating a synergistic effect between the anticancer activity of PHMB and the topical anticancer agent (e.g., 5-Fluoro uracil (5-FU)) when formulated according to the present disclosure.

Example 24. Topical Administration of Topical Anticancer Agent PHMB Compositions Improves Clinical Outcomes in Subjects Having Precancerous Lesions of the Skin

[00102] The effect of topical administration of the presently disclosed topical anticancer agent PHMB compositions in the treatment of human subjects having precancerous lesions of the skin will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed topical anticancer agent PHMB compositions including, but not limited to, Formulation Examples 4-5. In particular, the topical anticancer agent PHMB composition will be applied to a portion of the skin of a subject having or otherwise affected by precancerous lesions. Subjects receiving treatment using the presently disclosed topical anticancer agent PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit a reduced rate of occurrence of skin cancer in the portion of the skin receiving treatment. In subjects that develop skin cancer, the subject is expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate. [00103] Additionally, it is expected that the topical anticancer agent PHMB composition will enhance the skin penetration of the topical anticancer agent, ( e.g ., 5- Fluorouracil (5-FU)) and/or enhance the retention of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will exhibit enhanced efficacy and/or bioavailability of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will deliver the one or more topical anticancer agents to the target site with reduced skin irritation and/or increased patient comfort as compared with conventional topical anticancer agent compositions. Therefore, it is expected that topical anticancer agent PHMB compositions will be well-tolerated by the patients and result in enhanced patient compliance throughout treatment. In some instances, the administration of the topical anticancer agent PHMB compositions will result in greater improvement in one or more of the above clinical outcomes than administration of formulations comprising only PHMB (e.g., Formulation Examples 1-3) and formulations comprising the topical anticancer agent alone, thereby indicating a synergistic effect between the anticancer activity of PHMB and the topical anticancer agent (e.g., 5-Fluoro uracil (5-FU)) when formulated according to the present disclosure.

Example 25. Topical Administration of PHMB Compositions Improves Clinical Outcomes in Subjects Having Previously Undergone Surgical Treatment to Remove or Destroy Skin Cancer

[00104] The effect of topical administration of the presently disclosed topical anticancer agent PHMB compositions in the treatment of human subjects having previously received surgical treatment to remove or destroy skin cancer cells will be studied using a randomized, double-blind clinical study. During the clinical study, a group of human subjects will be topically administered one of the presently disclosed topical anticancer agent PHMB compositions including, but not limited to, Formulation Examples 4-5. In particular, the topical anticancer agent PHMB composition will be applied to a portion of the skin of a subject that has previously received surgical treatment to remove or destroy skin cancer cells. For example, the portion of the skin of the subject may have undergone excision, curettage, electrodessication, Mohs micrographic surgery, cryotherapy, cryosurgery, radiation therapy, or any combination thereof. Subjects receiving treatment using the presently disclosed topical anticancer agent PHMB compositions are expected to have improved standard clinical outcomes. In particular, subjects receiving treatment according to the presently disclosed methods and techniques are expected to exhibit a reduced rate of recurrence of skin cancer in the portion of the skin receiving treatment. In subjects that do develop skin cancer, the subject is expected to exhibit an improvement in one or more of the following clinical outcomes: reduction in tumor size (e.g., diameter), reduction in tumor growth rate, reduction in the number of tumors affecting the portion of skin receiving treatment, and decreased tumor recurrence rate.

[00105] Additionally, it is expected that the topical anticancer agent PHMB composition will enhance the skin penetration of the topical anticancer agent, (e.g., 5- Fluorouracil (5-FU)) and/or enhance the retention of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will exhibit enhanced efficacy and/or bioavailability of the topical anticancer agent at the target site. It is also expected that the topical anticancer agent PHMB composition will deliver the one or more topical anticancer agents to the target site with reduced skin irritation and/or increased patient comfort as compared with conventional topical anticancer agent compositions. Therefore, it is expected that topical anticancer agent PHMB compositions will be well-tolerated by the patients and result in enhanced patient compliance throughout treatment. In some instances, the administration of the topical anticancer agent PHMB compositions will result in greater improvement in one or more of the above clinical outcomes than administration of formulations comprising only PHMB (e.g., Formulation Examples 1-3) and formulations comprising the topical anticancer agent alone, thereby indicating a synergistic effect between the anticancer activity of PHMB and the topical anticancer agent (e.g., 5-Fluoro uracil (5-FU)) when formulated according to the present disclosure.

Example 26. Formulation 1 Inhibits the Activity of the Hedgehog Signaling Pathway Using Gli Reporter Assay

[00106] The Gli reporter assay was used to determine the inhibition effects of Formulation 1 and a PHMB aqueous solution on the activity of the Hedgehog signaling pathway. The compositions subject to the assay are shown in Table 18 below, including GDC- 0449/Vismodegib - Hedgehog signaling inhibitor (BPS Bioscience #27010). Formulation 1 was diluted for use in water based tissue culture media. 3l0mg of ointment was placed into lOmls of DMSO and the solution was warmed to 37°C, vortexed, sonicated and pressed w/ a pipet tip. After approximately 30 minutes of work, the solution was spun down at 400xG for 5 min. A significant amount of ointment remained visible and undissolved. The stock concentration of 0.000775% was attained based on 5% liquid in the ointment and 0.5% active ingredient in the liquid and assuming 100% recovery of active ingredient into lOmls of DMSO.

Table 18 - Test Compositions Subject to the Gli Reporter Assay

[00107] Hedgehog signaling pathway Gli Reporter NIH-3T3 cells were cultured in DMEM medium with 10% CS, 1% Pen-strep, and 500 pg/mL Geneticin. Gli Reporter - NIH- 3T3 cells were seeded at 25,000 cells per well into white clear-bottom 96-well microplate in 100 mΐ of growth medium without Geneticin. Cells were incubated at 37°C and 5% C0₂ overnight. The next day, media was removed and a serial dilution of compounds was prepared in assay medium (Opti-MEM, 0.5% CS, 1% non-essential amino acids, lmM sodium pyruvate, lOmM HEPES, 1% Pen/Strep). Ninety mΐ of diluted compounds was added to the treatment wells. Ninety mΐ of assay medium with the same concentration of DMSO without compound was added to the control wells. One hundred mΐ of assay medium with DMSO was added to cell-free control wells for determining background luminescence. Cells were incubated at 37°C and 5% C0₂ for 1-2 hours.

[00108] Ten mΐ of diluted mouse Shh in assay medium was added to wells (final [Shh] = 1 ug/ml). Ten mΐ of assay medium was added to unstimulated control wells. Cells were treated for 24-30 hours. After treatment, cells were lysed and the luciferase assay was performed using ONE-Step luciferase assay system: add 100 mΐ of One-Step Luciferase reagent per well and rock at room temperature for -30 minutes. Luminescence was measured using a luminometer (BioTek Synergy™ 2 microplate reader).

[00109] Reporter assays in triplicate were performed at each concentration. The luminescence intensity data were analyzed using the computer software, Graphpad Prism. In the absence of the compound, the luminescence intensity (L_t) in each data set was defined as 100%. In the absence of cells, the luminescence intensity (L_b) in each data set was defined as 0%. The percent luminescence in the presence of each compound was calculated according to the following equation: % Luminescence = (L-L_b)/(L_t-L_b), where L= the luminescence intensity in the presence of the compound, L_b= the luminescence intensity in the absence of cells, and L_t = the luminescence intensity in the absence of the compound.

[00110] The values of % luminescence versus a series of compound concentrations were then plotted using non-linear regression analysis of Sigmoidal dose-response curve generated with the equation Y=B+(T-B)/l+lO^{WLogEC50 X)xHlU slopcl}, where Y=percent luminescence, B=minimum percent luminescence, T=maximum percent luminescence, X= logarithm of compound and Hill Slope=slope factor or Hill coefficient. The IC50 value was determined by the concentration causing a half-maximal percent activity is shown in Table 19.

Table 19 - IC50 of Test Compositions Against Gli Reporter Activity

[00111] Table 20 shows the effect of Formulation 1 on Hedgehog Gli reporter activity in the presence of lug/ml Shh. As shown in Table 20, Formulation 1 inhibits the Activity of the Hedgehog Signaling Pathway according to the Gli reporter assay. Table 20 - Raw Data for the Effect of Formulation 1 on Hedgehog Gli reporter activity in the presence of lug/ml Shh

* exclude value, cell loss noted in some wells

[00112] Table 21 shows the effect of the aqueous solution of PHMB (Cosmocil CQ/Biguanide 20) on Hedgehog Gli reporter activity in the presence of lug/ml Shh. As shown in Table 21, the aqueous PHMB composition inhibits the Activity of the Hedgehog Signaling Pathway according to the Gli reporter assay.

Table 21 - Raw Data for the Effect of PHMB Aqueous Solution (Cosmocil

CQ/Biguanide 20) on Hedgehog Gli reporter activity in the presence of lug/ml Shh

[00113] Table 22 shows comparison data for the effect of GDC-0449 on Hedgehog Gli reporter activity in the presence of lug/ml Shh.

Table 22 - Raw Data for the Effect of GDC-0449 on Hedgehog Gli reporter activity in the presence of lug/ml Shh

* exclude value, cell loss noted in some wells

Statements of the Disclosure Include:

[00114] Statement 1: A petrolatum-based composition for the treatment of skin cancer, the composition comprising petrolatum and a pharmaceutically effective amount of polyhexamethylene biguanide (PHMB).

[00115] Statement 2: A petrolatum-based composition for the treatment of cancerous lesions of the skin, the composition comprising petrolatum and a pharmaceutically effective amount of polyhexamethylene biguanide (PHMB).

[00116] Statement 3: A petrolatum-based composition for the treatment of precancerous lesions of the skin, the composition comprising petrolatum and a pharmaceutically effective amount of polyhexamethylene biguanide (PHMB). [00117] Statement 4: A petrolatum-based composition for the inhibition of sonic hedgehog signaling in a skin cancer cell, the composition comprising petrolatum and a pharmaceutically effective amount of polyhexamethylene biguanide (PHMB).

[00118] Statement 5: A petrolatum-based composition for preventing or reducing the recurrence of skin cancer in a portion of skin having previously undergone surgical treatment, the composition comprising petrolatum and a pharmaceutically effective amount of polyhexamethylene biguanide (PHMB).

[00119] Statement 6: A petrolatum-based composition for the treatment of cutaneous basal cell carcinoma or cutaneous squamous cell carcinoma, the composition comprising petrolatum and a pharmaceutically effective amount of polyhexamethylene biguanide (PHMB).

[00120] Statement 7: A petrolatum-based composition according to Statement 1 or Statement 2, wherein the skin cancer or cancerous lesion is cutaneous basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (SCC).

[00121] Statement 8: A petrolatum-based composition according to any one of the preceding Statements 1-7, wherein the composition comprises greater than about 80% by weight petrolatum.

[00122] Statement 9: A petrolatum-based composition according to any one of the preceding Statements 1-8, further comprising a polar solvent.

[00123] Statement 10: A petrolatum-based composition according to Statement 9, wherein the polar solvent is selected from the group consisting of water, ethanol, and any mixture thereof.

[00124] Statement 11: A petrolatum-based composition according to Statement 9 or Statement 10, wherein the polar solvent and the PHMB are dispersed in the petrolatum in the form of nanodroplets.

[00125] Statement 12: A petrolatum-based composition according to any one of the preceding Statements 1-11, wherein the composition contains no emulsifier.

[00126] Statement 13: A petrolatum-based composition according to any one of the preceding Statements 1-12, further comprising a preservative selected from the group consisting of benzalkonium chloride, cetrimide, chlorhexidine, and any combination thereof. [00127] Statement 14: A petrolatum-based composition according to any one of the preceding Statements 1-13, wherein the composition comprises less than 1% by weight PHMB.

[00128] Statement 15: A petrolatum-based composition according to any one of the preceding Statements 1-13, wherein the composition comprises from about 0.1% to about 1% by weight PHMB.

[00129] Statement 16: A petrolatum-based composition according to any one of the preceding statements 1-13, wherein the composition comprises from about 0.2% to about 0.6% PHMB.

[00130] Statement 17: A petrolatum-based composition according to any one of the preceding Statements 1-13, wherein the composition comprises from about 0.3% to about 0.5% PHMB.

[00131] Statement 18: A petrolatum-based composition according to any one of the preceding Statements 1-17, wherein the composition comprises greater than about 90% by weight petrolatum.

[00132] Statement 19: A petrolatum-based composition according to any one of the preceding Statements 1-18, wherein the composition is prepared by a process comprising: a) dissolving the PHMB in a polar solvent to give a PHMB solution; b) heating the petrolatum to a temperature sufficient to cause the petrolatum to melt to give a melted petrolatum and heating the PHMB solution to a temperature higher than the temperature of the melted petrolatum to give a heated PHMB solution; c) mixing the melted petrolatum and the heated PHMB solution to give a melted mixture; and d) cooling the melted mixture to give the petrolatum-based composition.

[00133] Statement 20: A petrolatum-based composition according to Statement 19, wherein an emulsifier is not used.

[00134] Statement 21: A petrolatum-based composition according to Statement 19 or Statement 20, wherein the heated PHMB solution has a temperature that is about l°C to about 5°C higher than the temperature of the melted petrolatum.

[00135] Statement 22: A petrolatum-based composition according to any one of the preceding Statements 19-21, wherein the process does not include high shear mixing. [00136] Statement 23: A petrolatum-based composition according to any one of the preceding Statements 9-22, wherein the PHMB is dissolved in a polar solvent to form a PHMB solution, the PHMB solution dispersed in the petrolatum.

[00137] Statement 24: A petrolatum-based composition according to Statement 23, wherein the PHMB solution dispersed in the petrolatum in the form of a stable suspension.

[00138] Statement 25: A petrolatum-based composition according to Statement 24, wherein the PHMB solution does not separate from the petrolatum for at least six months.

[00139] Statement 26: A petrolatum-based composition according to any one of the preceding Statements 1-25, wherein the PHMB maintains efficacy for at least 3 months when stored at 40°C ± 2°C and 75% ± 5% relative humidity.

[00140] Statement 27: A petrolatum-based composition according to any one of the preceding Statements 5-26, wherein the surgical treatment is selected from the group consisting of excision, curettage, electrodessication, Mohs micrographic surgery, cryotherapy, cryosurgery, radiation therapy, and any combination thereof.

[00141] Statement 28: A petrolatum-based composition according to any one of the preceding Statements 4-27, wherein the skin cancer cell is cutaneous basal cell carcinoma.

[00142] Statement 29: A dressing configured to be applied to the skin of a patient, the dressing comprising a therapeutically effective amount of the petrolatum-based composition according to any one of the preceding claims 1-28.

[00143] Statement 30: A polyhexamethylene biguanide (PHMB) composition for the treatment of skin cancer, the composition comprising a pharmaceutically effective amount of PHMB in a pharmaceutically acceptable carrier.

[00144] Statement 31: A polyhexamethylene biguanide (PHMB) composition for the treatment of cancerous lesions of the skin, the composition comprising a pharmaceutically effective amount of PHMB and a pharmaceutically acceptable carrier.

[00145] Statement 32: A polyhexamethylene biguanide (PHMB) composition for the treatment of precancerous lesions of the skin, the composition comprising a pharmaceutically effective amount of PHMB and a pharmaceutically acceptable carrier.

[00146] Statement 33: A polyhexamethylene biguanide (PHMB) composition for the inhibition of sonic hedgehog signaling in a skin cancer cell, the composition comprising a pharmaceutically effective amount of PHMB and a pharmaceutically acceptable carrier. [00147] Statement 34: A polyhexamethylene biguanide (PHMB) composition for preventing or reducing the recurrence of skin cancer in a portion of skin having previously undergone surgical treatment, the composition comprising a pharmaceutically effective amount of PHMB and a pharmaceutically acceptable carrier.

[00148] Statement 35: A polyhexamethylene biguanide (PHMB) composition for the treatment of cutaneous basal cell carcinoma or cutaneous squamous cell carcinoma, the composition comprising a pharmaceutically effective amount of PHMB and a pharmaceutically acceptable carrier.

[00149] Statement 36: A PHMB composition according to Statement 30 or

Statement 31, wherein the skin cancer or cancerous lesion is cutaneous basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (SCC).

[00150] Statement 37: A PHMB composition according to any one of the preceding Statements 30-36, wherein the pharmaceutically acceptable carrier is selected from the group consisting of petrolatum, cocoa butter, jojoba oil, olive oil, soybean oil, coconut oil, beeswax, lanolin wax, carnauba wax, stearic acid, and any mixture thereof.

[00151] Statement 38: A PHMB composition according to any one of the preceding Statements 30-37, further comprising a polar solvent.

[00152] Statement 39: A PHMB composition according to Statement 38, wherein the polar solvent is selected from the group consisting of water, ethanol, and any mixture thereof.

[00153] Statement 40: A PHMB composition according to Statement 38 or

Statement 39, wherein the polar solvent and the PHMB are dispersed in the pharmaceutically acceptable carrier in the form of nanodroplets.

[00154] Statement 41: A PHMB composition according to any one of the preceding Statements 30-40, wherein the composition contains no emulsifier.

[00155] Statement 42: A PHMB composition according to any one of the preceding Statements 30-41, further comprising a preservative selected from the group consisting of benzalkonium chloride, cetrimide, chlorhexidine, and any combination thereof.

[00156] Statement 43: A PHMB composition according to any one of the preceding Statements 30-42, wherein the composition comprises less than 1% by weight PHMB. [00157] Statement 44: A PHMB composition according to any one of the preceding Statements 30-42, wherein the composition comprises from about 0.1% to about 1% by weight PHMB.

[00158] Statement 45: A PHMB composition according to any one of the preceding statements 30-42, wherein the composition comprises from about 0.2% to about 0.6% PHMB.

[00159] Statement 46: A PHMB composition according to any one of the preceding Statements 30-42, wherein the composition comprises from about 0.3% to about 0.5% PHMB.

[00160] Statement 47: A PHMB composition according to any one of the preceding Statements 38-46, wherein the PHMB is dissolved in a polar solvent to form a PHMB solution, the PHMB solution dispersed in the pharmaceutically acceptable carrier.

[00161] Statement 48: A PHMB composition according to Statement 47, wherein the PHMB solution dispersed in the pharmaceutically acceptable carrier in the form of a stable suspension.

[00162] Statement 49: A PHMB composition according to Statement 48, wherein the PHMB solution does not separate from the pharmaceutically acceptable carrier for at least six months.

[00163] Statement 50: A PHMB composition according to any one of the preceding Statements 30-49, wherein the PHMB maintains efficacy for at least 3 months when stored at 40°C ± 2°C and 75% ± 5% relative humidity.

[00164] Statement 51: A PHMB composition according to any one of the preceding Statements 34-50, wherein the surgical treatment is selected from the group consisting of excision, curettage, electrodessication, Mohs micrographic surgery, cryotherapy, cryosurgery, radiation therapy, and any combination thereof.

[00165] Statement 52: A PHMB composition according to any one of the preceding Statements 33-51, wherein the skin cancer cell is cutaneous basal cell carcinoma.

[00166] Statement 53: A dressing configured to be applied to the skin of a patient, the dressing comprising a therapeutically effective amount of the PHMB composition according to any one of the preceding claims 30-52. [00167] Statement 54: A method of treating skin cancer in a subject, the method comprising applying a polyhexamethylene biguanide (PHMB) composition to an area of the skin of the subject in need of treatment.

[00168] Statement 55: A method of treating cancerous lesions of the skin in a subject, the method comprising applying a polyhexamethylene biguanide (PHMB) composition to an area of the skin of the subject in need of treatment.

[00169] Statement 56: A method of treating precancerous lesions of the skin in a subject, the method comprising applying a polyhexamethylene biguanide (PHMB) composition to an area of the skin of the subject in need of treatment.

[00170] Statement 57: A method of preventing or reducing the recurrence of skin cancer in a portion of skin having previously undergone surgical treatment in a subject, the method comprising applying a polyhexamethylene biguanide (PHMB) composition to an area of the skin of the subject in need of treatment.

[00171] Statement 58: A method of inhibiting sonic hedgehog signaling in a skin cancer cell of a subject, the method comprising applying a polyhexamethylene biguanide (PHMB) composition to an area of the skin of the subject having a skin cancer cell in need of treatment.

[00172] Statement 59: A method of treating skin cancer in a subject, the method comprising inhibiting sonic hedgehog signaling in a skin cancer cell by contacting the skin cancer cell with a therapeutically effective amount of a polyhexamethylene biguanide (PHMB) composition.

[00173] Statement 60: A method of treating cutaneous basal cell carcinoma or cutaneous squamous cell carcinoma in a subject, the method comprising applying a polyhexamethylene biguanide (PHMB) composition to an area of the skin of the subject in need of treatment.

[00174] Statement 61: A method according to Statement 54 or Statement 55, wherein the skin cancer or cancerous lesion is cutaneous basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (SCC).

[00175] Statement 62: A method according to Statement 57, wherein the surgical treatment is selected from the group consisting of excision, curettage, electrodessication, Mohs micrographic surgery, cryotherapy, cryosurgery, radiation therapy, and any combination thereof. [00176] Statement 63: A method according to Statement 58 or Statement 59, wherein the skin cancer cell is cutaneous basal cell carcinoma.

[00177] Statement 64: A method according to any one of the preceding Statements 54-63, wherein the PHMB composition comprises petrolatum and a pharmaceutically effective amount of PHMB .

[00178] Statement 65: A method according to any one of the preceding Statement 64, wherein the composition comprises greater than about 80% by weight petrolatum.

[00179] Statement 66: A method according to Statement 64 or Statement 65, wherein the composition further comprises a polar solvent.

[00180] Statement 67: A method according to Statement 66, wherein the polar solvent is selected from the group consisting of water, ethanol, and any mixture thereof.

[00181] Statement 68: A method according to Statement 66 or Statement 67, wherein the polar solvent and the PHMB are dispersed in the petrolatum in the form of nanodroplets.

[00182] Statement 69: A method according to any one of the preceding Statements 64-68, wherein the composition contains no emulsifier.

[00183] Statement 70: A method according to any one of the preceding Statements 64-69, wherein the composition further comprises a preservative selected from the group consisting of benzalkonium chloride, cetrimide, chlorhexidine, and any combination thereof.

[00184] Statement 71: A method according to any one of the preceding Statements 64-70, wherein the composition comprises less than 1% by weight PHMB.

[00185] Statement 72: A method according to any one of the preceding Statements 64-70, wherein the composition comprises from about 0.1% to about 1% by weight PHMB.

[00186] Statement 73: A method according to any one of the preceding Statements 64-70, wherein the composition comprises from about 0.2% to about 0.6% PHMB.

[00187] Statement 74: A method according to any one of the preceding Statements 64-70, wherein the composition comprises from about 0.3% to about 0.5% PHMB.

[00188] Statement 75: A method according to any one of the preceding Statements 64-74, wherein the composition comprises greater than about 90% by weight petrolatum.

[00189] Statement 76: A method according to any one of the preceding Statements 64-75, wherein the composition is prepared by a process comprising: a) dissolving the PHMB in a polar solvent to give a PHMB solution; b) heating the petrolatum to a temperature sufficient to cause the petrolatum to melt to give a melted petrolatum and heating the PHMB solution to a temperature higher than the temperature of the melted petrolatum to give a heated PHMB solution; c) mixing the melted petrolatum and the heated PHMB solution to give a melted mixture; and d) cooling the melted mixture to give the petrolatum-based composition.

[00190] Statement 77: A method according to Statement 76, wherein an emulsifier is not used to prepare the composition.

[00191] Statement 78: A method according to Statement 76 or Statement 77, wherein the heated PHMB solution has a temperature that is about l°C to about 5°C higher than the temperature of the melted petrolatum.

[00192] Statement 79: A method according to any one of the preceding Statement 76-78, wherein the process to prepare the composition does not include high shear mixing.

[00193] Statement 80: A method according to any one of the preceding Statements 66-79, wherein the PHMB is dissolved in a polar solvent to form a PHMB solution, the PHMB solution dispersed in the petrolatum.

[00194] Statement 81: A method according to Statement 80, wherein the PHMB solution dispersed in the petrolatum in the form of a stable suspension.

[00195] Statement 82: A method according to Statement 81, wherein the PHMB solution does not separate from the petrolatum for at least six months.

[00196] Statement 83: A method according to any one of the preceding Statements 64-70, wherein the PHMB in the composition maintains efficacy for at least 3 months when stored at 40°C ± 2°C and 75% ± 5% relative humidity.

[00197] Statement 84: A method according to any one of the preceding Statements 54-63, wherein the PHMB composition comprises a pharmaceutically effective amount of PHMB in a pharmaceutically acceptable carrier.

[00198] Statement 85: A method according to Statements 84, wherein the pharmaceutically acceptable carrier is selected from the group consisting of petrolatum, cocoa butter, jojoba oil, olive oil, soybean oil, coconut oil, beeswax, lanolin wax, carnauba wax, stearic acid, and any mixture thereof.

[00199] Statement 86: A method according to Statement 84 or Statement 85, wherein the composition further comprises a polar solvent. [00200] Statement 87: A method according to Statement 86, wherein the polar solvent is selected from the group consisting of water, ethanol, and any mixture thereof.

[00201] Statement 88: A method according to Statement 86 or Statement 87, wherein the polar solvent and the PHMB are dispersed in the pharmaceutically acceptable carrier in the form of nanodroplets.

[00202] Statement 89: A method according to any one of the preceding Statements 84-88, wherein the composition contains no emulsifier.

[00203] Statement 90: A method according to any one of the preceding Statements 84-89, wherein the composition further comprises a preservative selected from the group consisting of benzalkonium chloride, cetrimide, chlorhexidine, and any combination thereof.

[00204] Statement 91: A method according to any one of the preceding Statements 84-90, wherein the composition comprises less than 1% by weight PHMB.

[00205] Statement 92: A method according to any one of the preceding Statements 84-90, wherein the composition comprises from about 0.1% to about 1% by weight PHMB.

[00206] Statement 93: A method according to any one of the preceding statements 84-90, wherein the composition comprises from about 0.2% to about 0.6% PHMB.

[00207] Statement 94: A method according to any one of the preceding Statements 84-90, wherein the composition comprises from about 0.3% to about 0.5% PHMB.

[00208] Statement 95: A method according to any one of the preceding Statements 86-94, wherein the PHMB is dissolved in a polar solvent to form a PHMB solution, the PHMB solution dispersed in the pharmaceutically acceptable carrier.

[00209] Statement 96: A method according to Statement 95, wherein the PHMB solution is dispersed in the pharmaceutically acceptable carrier in the form of a stable suspension.

[00210] Statement 97: A method according to Statement 96, wherein the PHMB solution does not separate from the pharmaceutically acceptable carrier for at least six months.

[00211] Statement 98: A method according to any one of the preceding Statements 54-97, wherein the subject is a mammal.

[00212] Statement 99: A method according to any one of the preceding Statements 54-97, wherein the subject is a human subject. [00213] Statement 100: A composition according to any one of the preceding Statements 1-52, further comprising a topical anticancer agent.

[00214] Statement 101: A composition according to Statement 100, wherein the topical anticancer agent comprises from about 0.5% to about 5% by weight of the composition.

[00215] Statement 102: A composition according to Statement 100 or Statement 101, wherein the topical anticancer agent is 5-fluorouracil (5-FU) and any prodrug, polymeric form, or derivative thereof.

[00216] Statement 103: A dressing configured to be applied to the skin of a patient, the dressing comprising a therapeutically effective amount of the composition according to any one of the preceding claims 100-102.

[00217] Statement 104: A method according to any one of the preceding Statements 54-99, wherein the composition further comprises a topical anticancer agent.

[00218] Statement 105: A method according to Statement 104, wherein the topical anticancer agent comprises from about 0.5% to about 5% by weight of the composition.

[00219] Statement 106: A method according to Statement 104 or Statement 105, wherein the topical anticancer agent is 5-fluorouracil (5-FU) and any prodrug, polymeric form, or derivative thereof.

Claims

CLAIMS What is claimed is:

1. A method of treating skin cancer in a subject, the method comprising applying a polyhexamethylene biguanide (PHMB) composition to an area of the skin of a subject in need of treatment.

2. The method according to claim 1, wherein the skin cancer is cutaneous basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (SCC).

3. The method according to claim 1, wherein the PHMB composition comprises a pharmaceutically effective amount of PHMB in a pharmaceutically acceptable carrier.

4. The method according to claim 3, wherein the pharmaceutically acceptable carrier is selected from the group consisting of petrolatum, cocoa butter, jojoba oil, olive oil, soybean oil, coconut oil, beeswax, lanolin wax, carnauba wax, stearic acid, and any mixture thereof.

5. The method according to claim 4, wherein the PHMB composition comprises greater than about 80% by weight pharmaceutically acceptable carrier.

6. The method according to claim 3, wherein the pharmaceutically acceptable carrier is petrolatum, the PHMB composition comprising greater than about 80% by weight petrolatum.

7. The method according to claim 3, wherein the pharmaceutically acceptable carrier is coconut oil, the PHMB composition comprising greater than about 80% by weight coconut oil.

8. The method according to claim 1, wherein the PHMB composition contains no emulsifier.

9. The method according to claim 1, wherein the PHMB composition further comprises a polar solvent selected from the group consisting of water, ethanol, and any combination thereof.

10. The method according to claim 1, wherein the PHMB composition comprises from about 0.1% to about 1% by weight PHMB.

11. The method according to claim 1, wherein the PHMB composition further comprises 5- fluorouracil (5-FU) or any prodrug, polymeric form, or derivative thereof.

12. The method according to claim 11, wherein the fluorouracil (5-FU) or any prodrug, polymeric form, or derivative thereof, comprises from about 0.5 wt% to about 5 wt% of the PHMB composition.

13. A method of treating skin cancer in a subject, the method comprising inhibiting sonic hedgehog signaling in a skin cancer cell by contacting the skin cancer cell with a therapeutically effective amount of a composition comprising polyhexamethylene biguanide (PHMB).

14. The method according to claim 13, wherein the skin cancer is cutaneous basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (SCC).

15. The method according to claim 13, wherein the composition comprises a

pharmaceutically effective amount of PHMB in a pharmaceutically acceptable carrier.

16. The method according to claim 15, wherein the pharmaceutically acceptable carrier is selected from the group consisting of petrolatum, cocoa butter, jojoba oil, olive oil, soybean oil, coconut oil, beeswax, lanolin wax, carnauba wax, stearic acid, and any mixture thereof.

17. The method according to claim 15, wherein the composition comprises greater than about 80% by weight pharmaceutically acceptable carrier.

18. The method according to claim 15, wherein the pharmaceutically acceptable carrier is petrolatum, the composition comprising greater than about 80% by weight petrolatum.

19. The method according to claim 15, wherein the pharmaceutically acceptable carrier is coconut oil, the composition comprising greater than about 80% by weight coconut oil.

20. The method according to claim 13, wherein the composition contains no emulsifier.

21. The method according to claim 15, wherein the composition further comprises a polar solvent selected from the group consisting of water, ethanol, and any combination thereof.

22. The method according to claim 15, wherein the composition comprises from about 0.1% to about 1% by weight PHMB.

23. The method according to claim 15, wherein the composition further comprises 5- fluorouracil (5-FU) or any prodrug, polymeric form, or derivative thereof.

24. The method according to claim 23, wherein the fluorouracil (5-FU) or any prodrug, polymeric form, or derivative thereof, comprises from about 0.5 wt% to about 5 wt% of the PHMB composition.

25. A composition for the treatment of skin cancer, the composition comprising a pharmaceutically effective amount of PHMB in a pharmaceutically acceptable carrier selected from the group consisting of petrolatum, cocoa butter, jojoba oil, olive oil, soybean oil, coconut oil, beeswax, lanolin wax, carnauba wax, stearic acid, and any mixture thereof.

26. The composition according to claim 25, wherein the composition comprises greater than about 80% by weight pharmaceutically acceptable carrier.

27. The composition according to claim 25, wherein the pharmaceutically acceptable carrier is petrolatum, the composition comprising greater than about 80% by weight petrolatum.

28. The composition according to claim 25, wherein the pharmaceutically acceptable carrier is coconut oil, the composition comprising greater than about 80% by weight coconut oil.

29. The composition according to claim 25, wherein the composition contains no emulsifier.

30. The composition according to claim 25, wherein the composition further comprises a polar solvent selected from the group consisting of water, ethanol, and any combination thereof.

31. The composition according to claim 25, wherein the composition comprises from about 0.1% to about 1% by weight PHMB.

32. The composition according to claim 25, wherein the composition further comprises 5- fluorouracil (5-FU) or any prodrug, polymeric form, or derivative thereof.

33. The composition according to claim 32, wherein the fluorouracil (5-FU) or any prodrug, polymeric form, or derivative thereof, comprises from about 0.5 wt% to about 5 wt% of the composition.

34. The composition according to claim 25, further comprising a preservative selected from the group consisting of benzalkonium chloride, cetrimide, chlorhexidine, and any combination thereof.

35. The composition according to claim 25, wherein the composition is prepared by a process comprising:

a) dissolving the PHMB in a polar solvent to give a PHMB solution;

b) heating the pharmaceutically acceptable carrier to a temperature sufficient to cause the carrier to melt to give a melted carrier and heating the PHMB solution to a temperature higher than the temperature of the melted carrier to give a heated PHMB solution;

c) mixing the melted carrier and the heated PHMB solution to give a melted mixture; and d) cooling the melted mixture to give the carrier-based PHMB composition.

36. The composition according to claim 35, wherein the heated PHMB solution has a temperature that is about l°C to about 5°C higher than the temperature of the melted carrier.

37. The composition according to claim 36, wherein the PHMB is dissolved in a polar solvent to form a PHMB solution, the PHMB solution dispersed in the pharmaceutically acceptable carrier to form a stable suspension.