It has been known for some years that the cosmetic severity of tissue scarring as a result of medical treatment and/or injury can be greatly reduced by the application of a silicone-containing sheet to the skin's surface. The mode of action remains unclear.

The first silicone-containing sheets used in order to reduce the visual severity of tissue scarring, based on a rubber containing formulation, were developed approximately 25 years ago and met with limited success since they were difficult to use. These silicone rubber sheets were secured on the skin surface with adhesive tape thereby forming a sealed enclosure. Typically, the silicone rubber sheet would be secured in place for 30 days during which time the skin would'remodel'itself to a large degree giving rise to a decrease in the cosmetic severity of the scar tissue.

Several theories have been postulated regarding the mode of action of the silicone layers. These include the moisture barrier properties of silicone, the leaching of low molecular weight silicone into the skin and the effect of the ionic content of the silicone.

Despite these silicone rubber sheets being expensive, they were widely used even though the location of their use on the skin surface was limited by their lack of flexibility.

The aforesaid silicone rubber sheets have since been replaced with softer self- adhesive silicone gel sheets, which possess a greater degree of flexibility by virtue of their polymeric oil-containing network structure. Therefore, although easier to apply, their use remains limited as a result of their sheet-like nature.

More recently liquid silicone compositions, which are predominantly composed of water, have been introduced. These are supplied in a tube and are specifically

designed to be applied to awkward areas, of the skins surface. Examples of said compositions include KELO-COTE (TM) or with a roller ball applicator, CICACARE (TM). Unlike the previously described sheets, which are intended to be worn for a period of approximately 3 0 days, these liquid silicone compositions require re-application every few hours as the silicone layer located over the wound is thinner. However, these compositions remain sticky and tacky after application, some fail to dry, whilst others take 10 to 30 minutes to dry.

Surprisingly, it has been found that it is now possible to provide a composition which delivers the aforesaid cosmetic scar severity reduction which is substantially water-free, but which is more convenient to use than previously available compositions as it dries quickly to a non-sticky film and has a substantially longer wear time than existing products such that it needs to be reapplied considerably less often.

According to the present invention there is provided a scar management composition in the form of a liquid gel wherein the composition is substantially water- free and comprises at least one silicone elastomer and/or gum.

Advantageously, the composition of the present invention is in the form of a surprisingly stable gel which is easy to manufacture and as such is suitable for application to all skin areas, but it is particularly useful for the application. to areas to which it is difficult to apply sheet material.

By liquid gel it is meant a composition having a viscosity in the range from 0. 01 cps to 500 000 cps when measured at 20°C.

By substantially water-free it is meant that the composition does not contain more than 3% water.

A further advantage of the composition of the present invention lies with its longer wear time, typically in excess of 8 hours. The longer wear time means that the composition can be worn for sufficiently long periods to enable moisture to develop under the sheet thus giving a skin softening and moisturising effect.

A still further advantage of the composition of the present invention is its rapid drying time, typically of about 2 minutes, thereby eliminating the undesirable tack of previously used liquid compositions which have a much longer drying time, typically in the order of 10 to 30 minutes.

Surprisingly, the composition of the present invention results in a greater reduction in the visual severity of a scar than that seen with previous methods of scar management.

Accordingly, the composition of the present invention is not only much easier and quicker to use than its predecessors but results in a greater reduction in the visual severity of scar tissue. Preliminary results obtained from an ongoing clinical study show that 100% of users reported that the appearance of their scars had improved during 6 weeks of treatment.

The silicone elastomer and/or gum preferably constitutes from 0. 01% to 80%, by weight, of the total composition of the present invention.

Silicone elastomers suitable for use with the composition of the present invention include any of the following either alone or in combination :- silicone elastomers, silicone crosspolymers, dimethicone crosspolymer, elastomer 10 (Dow Coming), Elastomer 40 (Dow Coming), silicone elastomer copolymers and partially reacted silicone elastomer (silicone elastomer prepolymers which will when reacted further give

rise to silicone elastomers or crosspolymers).

Silicone gums suitable for use with the present invention include any of the following either alone or in combination :- silicone gum, dimethiconols, dimethiconol esters, dimethiconol copolymers, dimethiconol crosspolymers, dimethiconol blends, dimethiconol blend 20 (Dow Coming) and partial reacted silicone gums (prepolymers which will hwne further reacted guve rise to silicone gums).

In addition to silicone elastomers and gums the composition of the present invention may comprise additional silicone components.

Additional silicone components suitable for use with the present invention include any of the following either alone or in combination:-silicone oils, silicone fluids, silicone solvents, silicone gels, silicone wax, silicone grease, silicone crosspolymers, silicone adhesives, silicone emulsifier, silicone wax emulsifier, silicone copolymer, silicone PSA's and other curing or partially cured silicone compounds.

Preferably the composition of the present invention shall contain at least one volatile solvent and most preferably at least one volatile organic solvent, for example isopropyl alcohol (IPA)., ethanol, methanol, low molecular weight silicone, cyclomethicone, volatile silicone fluids, ethoxydiglycol, hexane or any other skin compatible organic solvent.

Preferably the composition of the present invention comprises at least one thickening agent.

The said solvent may constitute from 0 % to 80%, by weight, of the total composition of the present invention.

The thickening agent preferably comprises from 0 to 50 % by weight of the total

composition.

Thickening agents suitable for use with the present invention include any of the following either alone or in combination :- high viscosity silicone fluids, silicone gels, silicone grease, silicone elastomer or cross polymer, silicone gum, silicone adhesive, silicone emulsifier, silicone wax emulsifier, reactive silicone component, silicone prepolymer and silicone co-polymer, hydroxypropyl cellulose, ethyl cellulose, cetyl hydroxyethyl cellulose, polyurethane, polyurethane copolymers, or any other polymer which is soluble or partial soluble in organic solvents.

In addition to the foregoing the composition of the present invention may also comprise any of the following, either alone or in combination :- active agents such as antibacterial agents, surfactants, antimicrobial agents, essential oil skin occlusion agents, copolymers and skin moisturisers, skin healing agents, scar healing agents, growth factors, or any compound which effects the level of growth factors in the skin, wound or scar, herbal agents, plant oils, essential oils or other plant extracts.

According to a second aspect of the present invention there is provided the use of a scar management composition as hereinbefore described to apply a coating of silicone elastomer and/or gum to human skin.

According to a further aspect of the present invention there is provided a method for forming a scar management coating of at least one silicone elastomer and/or gum to human skin comprising the step of applying the composition as hereinbefore described to a desired area of the skin.

According to a still further aspect of the present invention therefore there is provided a method of preparing a scar management composition as hereinbefore

described comprising the steps :- mixing together at least a first and a second two formulation wherein at least one of the first and second formulations comprises at least one silicone component.

During preparation of the composition of the present invention the first formulation may be added to the second formulation with vigorous mixing, again until a homogeneous gel ensues.

In order that the present invention be more readily understood the composition of the present invention will now be described further by way of example only with relation to the following examples :- Example 1 Cyclomethicone 5 and isopropyl Myristate were pre-mixed to form the first formulation as a homogenous mixture.

The first formulation was then added to Elastomer 10 (the second formulation) with vigorous stirring to furnish a surprisingly stable clear gel. Formulation Component Function Quantity (g) First Cyclomethicone 5 Silicone component 381.95 Isopropyl Myristate Solubilising agent 4.20 Second Elastomer 10 Silicone 33.85 NB: Drying time 485 seconds Example 2 Simogen carrier and isopropyl Myristate were pre-mixed to form the first formulation as a homogenous mixture.

The first formulation was then added to Elastomer 10 (the second formulation) with vigorous stirring to furnish a surprisingly stable clear gel.

Formulation Component Function Quantity (g) First Silmogen carrier A blend of silicone 196.0 solvent and silicone gum Isopropyl Myristate Solubilising agent 4.0 Second Elastomer 10 Silicone 200 NB: Drying time 123 seconds Example 3 Cetyl hydroxyl cellulose, propylene glycol and ethanol were pre-mixed to form the first formulation as a homogenous mixture.

The first formulation was then added to a mixture comprising Elastomer 10 and dimethicone blend 20 (the second formulation) with vigorous stirring to furnish a surprisingly stable clear gel Formulation Component Function Quantity (%) First Cetyl hydroxyl Thickener 2. 0 ethylcellulose Propylene glycol Moisturising agent 25.0 Ethanol Solvent 25. 0 Second Elastomer 10 Silicone elastomer 24.0 Dimethicone blend Silicone gum 24.0 20

Drying time: 525 seconds Wear Time Experiments 0.07g of the test scar management composition was applied to a 5 cm2 area of the skin. The area was wetted with water after lh, 2hrs, 4hrs and every 2hrs thereafter.

The scar management composition'passes'if the water forms an elevated bubble indicating that a significant amount of silicone is still present on the skin.

The scar management composition'fails'if the water does not form an elevated bubble indicating that little, if any, of the composition is still present on the skin. Wear Time (Hours) Formula Format Elastomer or gum 1 2 4 8 12 16 24 Product None pass pass fail Competitor KELOCOTE TM Comparative Hydrogel None pass pass fail example 1 Comparative Hydrogel Elastomer pass pass pass pass fail example 2 Example 1 Gel Elastomer pass pass pass pass pass pass fail Example 2 Gel Elastomer & gum pass pass pass pass pass pass pass Comparative example 1 Formulation Component Quantity (g) First Water 250. 19 Ethanol 108. 35 Carbopol 980NF 4.60 Nipagin M 0.29 Nipasol M 0.07 Second Dow Coming silicone fluid 56.5 Comparative example 2 Formulation Component Quantity (g) First Water 247. 55 Ethanol 108. 35 Carbopol 980NF 3.20 Nipagin M 0.29 Nipasol M 0.07 Second Elastomer 10 33. 85 Cyclomethicone 5 22.44 Isopropyl Mynstale 4. 25

It is of course to be understood that the invention is not intended to be restricted to the details of the above embodiments which are described by way of example only.