Mucoadhesive composition comprising chios mastic

Abstract

The present invention relates to the formulation of innovative pharmaceutical compositions for buccal use for use in the treatment and prevention of mucocutaneous diseases of the oral cavity. Said pharmaceutical compositions are able to resist salivary re-washing and have a high substantivity on the oral mucous membranes, obtaining a massive topical effect with the minimum possible systemic assimilation.

Description

[0001] MUCOADHESIVE COMPOSITION COMPRISING CHIOS MASTIC

[0002] TECHNICAL FIELD OF INVENTION

[0003] The present invention is related to a composition for oral use for the treatment of diseases of the oral cavity and is based on vegetable mastics such as Chios mastic.

[0004] KNOWN ART

[0005] The oral cavity is made up of a set of organs, each of which can be affected by different pathologies. There are several strategies that can be adopted for the treatment of diseases of the oral cavity. Systemic drugs are often used, although local administration has many advantages.

[0006] Topical buccal administration therefore refers to the administration of the drug directly on the area / lesion of the mouth to be treated, this allows for a pharmacological action on site, therefore targeted at the oral lesion avoiding a systemic action.

[0007] On some diseases of the oral cavity, for instance, it is necessary to administer drugs that inhibit the inflammatory process created by the disease itself, but unfortunately the anti-inflammatory drugs to be used on the market are almost all usable through systemic administration which therefore exposes the patient to high doses of drug and sometimes to side and unwanted effects. Consequently, topical administration remains the best route of administration to minimize dosage and the occurrence of systemic side effects or interactions with other drugs or other diseases.

[0008] Topical administration, however, is made difficult by the little or no substantiality of the drugs currently in use at the level of the oral cavity which is constantly subjected to irrigation by saliva (salivary rewashing) and continuous stimuli from chewing and phonatory movements. It is from this difficulty that the need emerges for galenic products other than conventional ones that have a high substantivity on the oral mucous membranes and a massive topical effect, but with the minimum possible systemic assimilation.

[0009] Current buccal topical systems have limitations: • those related to the organoleptic properties of the formulation which, if it were in bad taste, would reduce patient compliance;

[0010] • low local bioavailability of the drug linked to the enzymatic presence of esterases, carbohydrase and phosphatases contained in saliva that can degrade the active ingredient before it carries out its therapeutic activity or linked to partial systemic absorption;

[0011] • short residence time of the drug caused: i) by salivary re-washing, ii) by involuntary ingestion of saliva, this could lead to the loss of the available drug;

[0012] • irritation of the buccal mucosa.

[0013] Lichen Planus (or Lichen Ruber Planus) is an example of a benign mucocutaneous pathology, with an inflammatory character with a variable course, caused by an altered cell-mediated immune response to exogenous or endogenous antigens. It can show up with acute episodes that resolve spontaneously in variable times or with lesions that tend to persist chronically. Lesions tend to persist chronically, especially in the hypertrophic cutaneous variant and in the erosive mucosal variant, so that there is an increased risk of the appearance of squamous cell carcinoma.

[0014] Lesions on the mucous membranes mainly present as whitish shiny striae or eroded areas. The most affected mucosa is that of the oral cavity, in particular the cheeks are affected, but it also involves the tongue, palate, lips, gums and oral floor.

[0015] The accompanying symptomatology is itching, which can also be very intense, and, in the case of erosive lesions, burning and pain. These symptoms can affect psycho-physical well-being and, for lesions of the oral cavity, nutrition.

[0016] There remains a need to create innovative pharmaceutical forms for topical use, which can improve the pharmacokinetic profile of the drug by overcoming the problems described above and other critical issues of conventional systems, develop a pharmaceutical formulation capable of improving and expanding the therapeutic treatment possibilities currently available for patients suffering from various diseases of the oral cavity such as, for instance, Oral Lichen Planus, using innovative formulations that overcome the limits of current therapies: short residence time of the drug caused by salivary re-washing or involuntary ingestion of saliva; these characteristics determine the loss of the drug from the site of absorption with consequent low absorption.

[0017] SUMMARY OF THE INVENTION

[0018] The purpose of the present invention is the formulation of innovative pharmaceutical compositions for buccal use capable of overcoming the limits of the compositions currently available.

[0019] Therefore, an object of the present invention are pharmaceutical compositions capable of resisting salivary re-washing and with a high substantivity on the oral mucous membranes and a massive topical effect (i.e. with a pharmacological activity exerted directly on the lesion of the oral mucosa where it is applied), but with the minimum possible systemic assimilation.

[0020] The object of the present invention is also a pharmaceutical composition as described above for use in the treatment and prevention of mucocutaneous diseases of the oral cavity.

[0021] The composition in the form of cream, gummy candies, chewing gum, hard tablets, lollipops and candies and the related production processes are also the objects of the present invention.

[0022] Other objects, purposes and advantages will be evident from the detailed description of the invention that follows.

[0023] BRIEF DESCRIPTION OF THE FIGURES

[0024] Figure 1: Appearance of the post-preparation high viscosity cream.

[0025] Figure 2: Images obtained with an optical microscope with 400X magnification:

[0026] Figure A: Commercial ointment containing 0.05% corticosteroid.

[0027] Figure B: Corticosteroid-free cream (empty).

[0028] Figure C: Corticosteroid cream.

[0029] Figure 3: Graph of corticosteroid release over time. Figure 4: Graph of the muco-adhesion test of cream without drug, cream with drug and medicine with MA. The data were obtained as an average of three independent experiments.

[0030] Figure 5: Cream weight values (25°C and 4°C) over time. The SD values are all in the range ± 0.01-0.02.

[0031] Figure 6: Graph of free corticosteroid stability (stored at 25°C: panel A and at 4°C: panel B) over time. The data were obtained as an average of three independent experiments.

[0032] Figure 7: Study of the weight stability of drug-free candy at 25°C (a) and 4°C (b). The SD values are all in the range of ± 0.01-0.02.

[0033] Figure 8: UV analysis: peak of the corticosteroid contained in the candy stored at 25°C (panel A). The data were obtained as an average of three experiments. Peak of the contained corticosteroid in the candy stored at 4°C (panel B). The data were obtained as an average of three experiments.

[0034] Figure 9: Results of the "A" dissolution test applied to the cream.

[0035] Figure 10: Results of the "A" dissolution test of the corticosteroid-free candy, stored at 25 °C, over 4 weeks.

[0036] Figure 11: Results of the "A" dissolution test of the candy without corticosteroid, stored at 4°C, over 4 weeks.

[0037] Figure 12: Results of the "A" dissolution test of the corticosteroid-containing candy, stored at 25 °C, over 4 weeks.

[0038] Figure 13: Results of the "A" dissolution test of the corticosteroid-containing candy, stored at 4°C, over 4 weeks.

[0039] Figure 14: Graph of corticosteroid release from candy. The data were obtained as an average of three independent experiments.

[0040] Figure 15: Results of the muco-adhesion test of the candy without corticosteroid and with corticosteroid, stored at temperatures of 25°C and 4°C.

[0041] Figure 16: Weight stability of gums without active ingredient at 25°C (A) and 4°C (B). Figure 17: Weight stability of gums with active ingredient at 25°C (C) and 4°C (D).

[0042] Figure 18: Image of buccal lesion prior to treatment with the medicated gummy candy containing the corticosteroid.

[0043] Figure 19: Image of buccal lesion after treatment with medicated gummy candy containing corticosteroid.

[0044] Figure 20: Pre-treatment picture of the reticular lichen planus lesion on the left genienous mucosa.

[0045] Figure 21: Post-treatment picture of the lichen planus lattice lesion on the left genienous mucosa.

[0046] Figure 22: Comparative formulation test between the composition in the presence of Tween 80 and the composition in the presence of Span 65.

[0047] Figure 23: Appearance of the composition of the invention in the presence of Span 65.

[0048] DETAILED DESCRIPTION

[0049] The aim of this invention is to obtain pharmaceutical compositions capable of improving and expanding the therapeutic treatment possibilities currently available for mucus skin diseases of the oral cavity, by way of non-limited example Oral Lichen planus, Lichenoid lesions, Oral lesions from GVHD, Congenital epidermolysis bullosa, Acquired epidermolysis bullosa, Pemphigus, Pemphigoid, Aphthosis minor and major, Oral manifestations of Lupus Erythematosus, Stomatitis, Atrophic-erosive and ulcerative lesions of various kinds.

[0050] In particular, the inventors had the goal of obtaining a basic composition with organoleptic properties of the formulation such as to be palatable for patients, able to resist salivary re-washing and with a high substantivity on the oral mucous membranes and a massive topical effect.

[0051] This basic composition is made in semi-solid physical form intended for topical oral application. In the context of the present invention this composition will be defined as "cream"; according to the invention, the cream is to be used as such, with the addition of an active ingredient specific to the condition to be treated and also formulated in pharmaceutical forms suitable for the treatment of the oral cavity such as chewing gum, candies and lollipops.

[0052] The inventors have studied different components to make high viscosity creams to be used for the treatment of mucus skin diseases of the oral cavity, testing different compositions to create different formulations capable of having high muco-adhesiveness, incorporating an active ingredient suitable for the purpose and having a taste such as to increase patient compliance, in particular to be used for the treatment of animals and humans, comprising the elderly, infants and children.

[0053] The present invention therefore covers a composition comprising at least one natural resin, in combination with at least one surfactant and one flavouring. In a preferred embodiment, the composition according to the invention additionally comprises at least one pharmaceutically active ingredient.

[0054] The resin of natural origin selected is Chios mastic. In the context of the present invention, Chios mastic also comprises mastic gum, Greek mastic, mastic, lentisk, chondro. In particular, Chios mastic is the dried resinous exudate from the stems and branches of Pistacia lentiscus L trees.lt is widespread in some Greek islands and is used in the present invention both for its anti-inflammatory activity capable of assisting the action of active molecules and therefore synergistically enhancing the potential of any active ingredient to treat inflammatory states of the oral cavity, and for its ability to give the composition muco-adhesive properties thanks to its high sticky character and high viscosity.

[0055] It is composed of a large number of bioactive constituents, such as phenolic compounds, phytosterols, monoterpenes (a-pinene, P-pinene and P-myrcene) and triterpenes (masticadienoic acid and isomasticadienoic acid).

[0056] In particular, in a preferred embodiment the Chios mastic according to the invention comprises:

[0057] 50% Masticine resin C22H56O4

[0058] 8-14% Masticadienoic acid C22H48O4 5-8% Oleanolic acid

[0059] 1-3% Essential Oil

[0060] 8-14% Isomasticadienoic acid

[0061] 20-30% polymer fraction (poly -beta- myrcene).

[0062] In one embodiment, the Chios mastic according to the invention is in the form of drops of intense yellow color. In a preferred embodiment the Chios mastic must be treated for the preparation of the composition.

[0063] Other starting forms are however suitable for the purpose.

[0064] In the preparation of the composition, Chios mastic is used in combination with at least one nonionic surfactant.

[0065] Although nonionic surfactants are generally recognized and used for the stabilization of mixtures containing non-miscible or poorly compatible components, the inventors surprisingly found that, in the technical context of the invention, such a stabilizing effect is not achievable by the indiscriminate use of a generic nonionic surfactant. Therefore, the mere presence of a surfactant, even if non-ionic, is not sufficient to guarantee the desired performance of the final product.

[0066] On the contrary, the formulation of a stable, homogeneous, suitably viscous composition and uniformly applicable on mucosal or tissue surfaces, is strictly linked to the use of non-ionic surfactants with specific and selected chemicalphysical properties.

[0067] Surfactants can be classified both according to their nature (e.g., zwitterionic, ionic, neutral) and the HLB (Hydrophilic-Lipophilic Balance) parameter. This parameter is a number that is assigned to a generic surfactant / emulsifier and indicates the lipophilicity / hydrophilicity ratio of the compound, i.e. its relative polarity. In the system proposed by Griffin, a nonionic surfactant theoretically 100% hydrophilic is assigned a value of 20, therefore surfactants with an HLB value greater than 10 are to be considered hydrophilic, while those with an HLB lower than 10 are lipophilic. The calculation methodologies are for instance described in the basic text Micheal E. Aulton, Kevin M.G. Taylor "Tecnologie farmaceutiche, Progettazione e allestimento dei medicinali" edited by Gabriele Caviglioli, Tommasina Coviello, Giuseppe De Rosa, Tiziana Moderna, Edra Editore and are therefore within the reach of the average technician.

[0068] The HLB value, in fact, can influence the stability of the pharmaceutical form obtained. The inventors surprisingly observed that only surfactants with an HLB value > 10 are suitable for the composition of the invention. These surfactants are able to stabilize this composition and guarantee its correct spreadability, viscosity, homogeneity, uniformity, without altering its adhesive properties.

[0069] Surfactants with high HLB values (> 10) or surfactant mixes are also suitable for the invention; in the latter case, surfactants of a more hydrophilic nature with HLB >10 can be used, which will be mixed with surfactants with lower HLB, so as to still have an overall HLB >10.

[0070] In a preferred embodiment, one or more nonionic surfactants are used, having a total HLB greater than 10.

[0071] Different types of surfactants with significantly different HLB values have been tested. In particular, creams composed of surfactants (at the same quantities) with HLB values lower than 10 were formulated under the same operating conditions (described below) and stability over time, even in very short times, in terms of separation of the aqueous phase from the oily phase, was not guaranteed. The use of surfactants with HLB values below 10 always resulted in unsuitable samples.

[0072] Surfactants with higher HLB values were found to be more suitable for obtaining a formulation that was fairly homogeneous, stable, sticky and dense, but spreadable. Of course, it was necessary to test different formulations with different ratios of resin and water and surfactant before optimizing the composition.

[0073] The comparative experiment reported in the Examples section (Formulation studies) and the respective figures 22-23 have highlighted how two nonionic surfactants having a different HLB value, the first greater than 10 (i.e., tween 80) and the second less than 10 span 65), can have a different impact on the chemicalphysical properties of the system. If the more hydrophilic surfactant has favored the achievement of a uniform, homogeneous, viscous and easily applied formulation, the more lipophilic one has led to the formation of a granular mixture, not homogeneous and difficult to spread on a surface. This experimental evidence is a proof of the need to select among the entire range of existing nonionic surfactants, only those that have an HLB value (proportion between hydrophilic and lipophilic residues) greater than 10. A particularly lipophilic surfactant such as sorbitan tristearate (Span 65) is not able to exert an emulsifying and stabilizing power such as to guarantee the formation of a homogeneous, viscous and spreadable preparation.

[0074] The surfactant contained in the composition of the invention is preferably chosen from the group of polysorbates, sorbitan esters and polyoxyethylenes and mixtures thereof. These surfactants act by reducing surface / interfacial tension and facilitating the homogeneous dispersion of phases.

[0075] Particularly preferred are polyoxyethylenes with HLB values greater than 10 such as, for instance, Polyoxyethylene (20) sorbitan monolaurate (Tween® 20), Polyoxyethylene (4) sorbitan monolaurate (Tween® 21), Polyoxyethylene (20) sorbitan monooleate (Tween® 80), Polyoxyethylene sorbitan trioleate (Tween® 85), Polyoxyethylene sorbitan monopalmitate (Tween® 40), Polyoxyethylene sorbitan mono stearate (Tween® 60).

[0076] It can be concluded that the selection of a specific surfactant plays a crucial role in the design and optimization of the formulation. Not all surfactants, in fact, are able to guarantee the same characteristics to the final formulation in terms of homogeneity, physical stability, adhesiveness and control of the release of the active ingredient.

[0077] Tween 80 is particularly preferred. Tween 80 is composed of polysorbate with oleic acid (C18H34O2) incorporated into the compound, with an unsaturation in position 9 (omega-9) is particularly preferred for its chemical-physical characteristics, and because it is already used in various fields of application and is used in the food, cosmetic and pharmaceutical sectors. Tween 80 is particularly preferred because, in addition to allowing optimal stability of the preparation, it has proven to have the ideal characteristics to guarantee a homogeneous appearance and an adhesive consistency to the product. Not only that, being structurally composed also of oleic acid (a compound with mild antiinflammatory activity), said Tween 80 is able to assist in vivo the activity of the oil and the active ingredient contained in the preparation. In the context of the invention, Tween 80 also confers the technical advantage of guaranteeing effective dissolution kinetics, allowing a gradual and controlled release of the active ingredient contained in the composition. According to the invention, this property ensures a therapeutically relevant contact time (estimated at around 20 minutes) with the lesion, during which the active ingredient can optimally exert its action. Advantageously, Tween 80 inhibits the rapid release of the active ingredient, limits systemic absorption through swallowing, instead promotes a localized action at the level of the treated mucosal or tissue surface and reduces the risk of systemic side effects. Tween 80 also benefits from allowing the release of the active ingredient to be excessively slow. Too slow dissolution may not ensure sufficient contact time of the active ingredient with the lesion while the product remains in the oral cavity, compromising the desired therapeutic effect before the system is mechanically removed (salivation, swallowing, speech).

[0078] The other surfactants listed above are in any case suitable for the purpose.

[0079] The choice of a suitable nonionic surfactant with an HLB >10 (for a more or less rapid release) can be made on the basis of the desired performance of the formulation.

[0080] The composition according to the invention further comprises a flavour aimed at making the taste of the composition for oral use acceptable and pleasant, thus increasing patient compliance.

[0081] Powdered flavourings are preferred, especially flavours that can counteract the salty and acidic flavour of Chios mastic. As a non-limiting example, it is possible to use the flavour of caramel, lemon, orange, vanilla, grapefruit, tangerine, lime, strawberry and cherry. Particularly preferred is the orange flavour.

[0082] The composition according to the invention additionally comprises at least one pharmacologically active ingredient for use in the treatment of cutaneous mucus pathologies of the oral cavity.

[0083] By way of non-limiting example, one or more steroidal or non-steroidal antiinflammatory agents, steroids and corticosteroids, analgesics and local anaesthetics, antibiotics, antifungals, antivirals, antiseptics, bactericides, healing, keratolytic and re-epithelializing agents may be present in the composition.

[0084] Corticosteroids are particularly preferred. In an embodiment the pharmacologically active ingredient is chosen from the group of Clobetasol, Chlorhexidine, Fluocinonide, Acyclovir, Nystatin, Miconazole.

[0085] In a preferred embodiment, the active ingredient is clobetasol propionate at a final % by weight of 0.05%.

[0086] In order to create a composition in cream form that had the correct characteristics of viscosity and mucus adhesion, several experiments were carried out.

[0087] Chios mastic, first of all, comes in solid drops, and the first studies were carried out on solid drops, as such, to evaluate their melting temperature which occurred to be 70°C, obtaining a compound with a caramel-like consistency, i.e. very sticky and dense, which congeals very quickly and not very workable when cooled.

[0088] The inventors therefore thought of pulverizing the resin. The resin powder is obtained after grinding the solid drops, preferably by means of a pestle and mortar with subsequent sieving in 0.315 mm sieves.

[0089] The resin powder was found to melt in a few minutes at 50-56°C. Cooling also in this case led to a product that set very quickly, making the composition difficult to work with. In order to obtain a more workable and spreadable formulation, water was added to the melt at a temperature higher than the ambient temperature to avoid its sudden cooling. However, this type of preparation led to a phase separation due to the different polarity of the components. In order to stabilize the formulation, therefore, a surfactant in appropriate concentration was analysed and selected.

[0090] The composition according to the invention therefore comprises: In a preferred embodiment, the composition comprises tween 80 as a surfactant.

[0091] In a preferred embodiment the composition comprises clobetasol as a pharmaceutical active ingredient.

[0092] In a preferred embodiment, the composition comprises tween 80 as a surfactant and clobetasol as a pharmaceutical active ingredient.

[0093] In a preferred embodiment, the composition additionally contains one of the following antioxidants and / or preservative agents:

[0094] • Preserved water

[0095] • Methyl para hydroxybenzoate (sodium nipagin)

[0096] • Propyl para hydroxybenzoate (Sodium nipasol)

[0097] • Ascorbic acid

[0098] • Sodium erythorbate

[0099] • Citric acid

[0100] Among the listed antioxidant agents, preserved water is particularly preferred, whose composition is reported.

[0101] Sodium nipasol 0.25 g

[0102] Sodium nipagin 0.75 g

[0103] Highly purified water up to 1 1

[0104] In a preferred embodiment the composition comprises:

[0105] Several formulation tests have been carried out to obtain a homogeneous and stable formulation: Test 1)

[0106] • Melt the Chios mastic "tears" at 70°C;

[0107] • Mix everything, using a Vortex Stirrer at room temperature, until you get a homogeneous paste (yellow in color);

[0108] • Add 1 ml of distilled water (the paste becomes white);

[0109] • Mix until homogeneous;

[0110] • Sonicate with bath at 70°C:

[0111] SONICATION PARAMETERS

[0112] T: 70°C

[0113] Amplitude: 25%

[0114] Time: 15 min

[0115] The preparation obtained has a very unworkable consistency, since when cooled the Chios mastic forms granules inside the preparation

[0116] Test 2)

[0117] • To overcome the phenomenon of aggregation of Chios mastic tears, it was decided to use Chios mastic in powder form;

[0118] • Melt the powder at 70°C with the addition of distilled water and add the other components until a homogeneous paste (yellow) is obtained; • Upon cooling, by placing the sample at room temperature, the compound becomes dense and non-sonicable.

[0119] The preparation obtained was found to be not very workable

[0120] Test 3)

[0121] • Mix everything, using a Vortex Stirrer at room temperature, until a homogeneous paste (yellow in color) is obtained;

[0122] • Add 1 ml of distilled water (the paste becomes white);

[0123] • Mix until homogeneous;

[0124] • Sonicate with bath at 65°C:

[0125] SONICATION PARAMETERS

[0126] T: 65°C

[0127] Amplitude: 25%

[0128] Time: 15 min

[0129] The preparation obtained, which is not very workable, showed very unpleasant organoleptic characteristics.

[0130] Test 4)

[0131] • Mix everything, using a Vortex Stirrer at room temperature, until a homogeneous paste (yellow in color) is obtained Add 1 ml of distilled water (the paste becomes white)

[0132] • Mix until homogeneous

[0133] • Sonicate with 65°C bath

[0134] SONICATION PARAMETERS

[0135] T: 65°C

[0136] Amplitude: 25%

[0137] Time: 15 min

[0138] After sonication, when the compound is still hot, add:

[0139] • 0.5 g of orange flavouring powder and mix until homogeneous and pour into the container

[0140] • Store at 4°C after cooling

[0141] After preparing different formulations, using different ratios of the selected components, and optimizing the preparation method, a spreadable formulation with a sticky and viscous appearance was obtained.

[0142] Test 5)

[0143] • Mix everything, using a Vortex Stirrer at room temperature, until a homogeneous paste (yellow in color) is obtained

[0144] • Add 1 ml of distilled water (the paste becomes white)

[0145] • Mix until homogeneous

[0146] • Sonicate with 65 °C bath

[0147] SONICATION PARAMETERS

[0148] T: 65°C

[0149] Amplitude: 25% Time: 15 min

[0150] After sonication, when the compound is still hot, add:

[0151] • 0.5 g of orange flavouring powder and mix until homogeneous and pour into the container

[0152] • Store at 4°C after cooling

[0153] The selected formulation, therefore, involves the use of Chios mastic powder, to be mixed with the surfactant, the aqueous phase and the active ingredient.

[0154] Suitable storage will be at 4°C.

[0155] As can be seen from figure 1, the cream obtained was smooth, without lumps and with a homogeneous appearance.

[0156] In the context of the present invention, the terms pulverize, grind, crunch are to be understood as synonyms.

[0157] PREPARATION PROCESS

[0158] The preparation of the base cream takes place following the following basic steps:

[0159] • Pulverize the Chios mastic and sift the powder.

[0160] If in drops, the mastic drops are pulverized by known methods, e.g. by the use of a mortar and pestle. The powdered sample is deposited in the sieve 0200 mm mesh size 0.315 mm (DIN 4188), replacing the lid. Shake the sieve column for 5 min, carefully separating the sieve from the column to avoid loss of Substance. Repeat the process until all the powdered drops are sifted.

[0161] • Mix the Chios mastic powder thus obtained with the surfactant until a homogeneous paste is obtained

[0162] • Add distilled water, preferably preserved water (in a 1 : 1 ratio)

[0163] • Mix until homogeneous

[0164] • Subject the composition to the action of a sonicator (preferred sonication parameters)

[0165] • T: 65°C

[0166] Amplitude: 25% Time: 15 min

[0167] After sonication, add the flavoring and stir until a homogeneous mixture is obtained and pour into a container suitable for storage

[0168] • Cool to room temperature

[0169] • Store preferably at 4 °C after cooling

[0170] Preferably, the flavour according to the method of preparation of the invention is added in powdery form. Compared to the use of different formulations (e.g., liquid flavoring forms), the powder limits and / or inhibits phenomena of destabilization of the balance between the oil phase and the aqueous phase.

[0171] Preferably, in the technical context of the preparation of the invention, the flavour is added after the sonication step. The inclusion of the flavour during sonication, in fact, can compromise the homogeneity of the final composition, lead to a loss of organoleptic properties and generate unpleasant odors.

[0172] The composition according to the invention can be used as a basis for the creation of other formulations suitable for oral administration, as a non-limiting example it is possible to make gummy candies, chewing gum and lollipops. The implementation of these formulations will be detailed below.

[0173] The inventors investigated the morphological characterization of the composition according to the invention both in the presence and in the absence of a pharmaceutically active ingredient.

[0174] In particular, a composition according to the invention comprising clobetasol was used by comparing it with a cream not comprising the active ingredient (empty cream) and a cream with 0.05% clobetasol propionate (Clobesol® cream).

[0175] The results are shown in Figure 2.

[0176] In both creams comprising Chios mastic (figures B and C) larger sizes of the dispersed phase can be observed compared to the cream on the market containing 0.05% clobetasol (figure A) used as standard.

[0177] In particular, the sample without active ingredient (figure B) has larger dispersed phase droplets (about 250 micrometers on average) compared to those of the corticosteroid sample (figure C), wherein the droplets appear more homogeneous in terms of size (about 80 micrometers on average) and distribution. Probably for sample B the larger size of the droplets that are observed is a consequence of coalescence phenomena. This phenomenon is not observed, instead, for sample C wherein the active ingredient is present, which thanks to its chemical nature could behave almost like a surfactant, stabilizing the formulation, which is more homogeneous and comparable to the product on the market. (Clobesol 0.05%)

[0178] In order for the active ingredient of solid / semi- solid pharmaceutical forms to be made available to exert its therapeutic action, the formulations must undergo a process of dissolution in biological fluids which consists of two fundamental steps:

[0179] 1) phase transition, wherein the solid becomes solute at the interface between the surface of the solid and the dissolving medium. Thus, at the interface, a thin layer of saturated solution called the diffusion layer is formed;

[0180] 2) transport by diffusion of the solute from the solid-liquid interface to the circulating solution (bulk), wherein the concentration is lower.

[0181] Thus, the speed of the dissolution process is defined by the diffusion process, which is mathematically represented by the Noyes-Whitney Law: dc / dt = k S (cS - cT)

[0182] Wherein:

[0183] • dc / dt corresponds to the rate of dissolution, i.e. the change in concentration per time unit;

[0184] • k is the diffusion coefficient;

[0185] • S is the specific surface area of the particles (area per unit volume);

[0186] • cS is the concentration in the diffusion layer, i.e. the solubility of the substance;

[0187] • cT is the concentration in the surrounding solvent (bulk) at time t.

[0188] Therefore (cS - cT) corresponds to the concentration gradient.

[0189] As can be seen from the equation, dissolution is influenced by several factors, the main ones being: • specific surface area, i.e. the ratio between the area and the volume of the solid particle., which increases as the size of the particle decreases;

[0190] • solubility, which corresponds to the maximum concentration of a solute in a known amount of solvent at a given temperature;

[0191] • diffusion coefficient, on which the amount of solute diffusing through the diffusion layer depends. In turn, k depends on the molecular mass of the solute (the larger the size of the molecule, the greater the diffusion coefficient), on the concentration of the solute, the viscosity of the medium (the higher the viscosity of the solvent, the lower the diffusion coefficient, since the flow between the solvent and solute molecules is slowed down), on the temperature (the higher the temperature, the greater the diffusion coefficient, since the kinetic energy and therefore the movements of the solute increase);

[0192] • temperature and stirring of the system;

[0193] • characteristics of the solvent, such as pH.

[0194] Two dissolution studies, A and B as detailed in the examples, have therefore been performed on the compositions according to the invention.

[0195] The dissolution study on empty cream is performed by means of the dissolution test A. During these studies, the "dissolution" of the cream placed in a basket in a known quantity is performed, monitoring, at set time intervals, the decrease in the weight of the basket. The experiment is performed for 20 minutes to mimic the residence time in the mouth of the cream once applied to the lesions.

[0196] The data collected are shown in table 1.

[0197] The experiment was performed on both empty cream and corticosteroid cream (cream + C).

[0198] From the results obtained, it can be seen that both formulations dissolve 100% at the end of the experiment.

[0199] Subsequently, the "dissolution" A test is also performed on the corticosteroid cream, with the same method performed on the cream without the active ingredient. Also in this case, after 20 minutes, the complete dispersion of the sample is observed without any cream residue in the basket.

[0200] Table 1: Dissolution values A on empty and full cream. The SD values are all in the range ± 0.01 - 0.02.

[0201] Such a dissolution study is also performed over time on corticosteroid cream, stored for 4 weeks, to monitor that the dissolving capacity did not change due to storage.

[0202] Measurements were carried out on a weekly basis both on the sample stored at 25°C and on the sample stored at 4°C.

[0203] The dissolution time of the cream remains unchanged over time; in fact, the sample is always dissolved after 20 minutes.

[0204] The same dissolution test was carried out on a commercially available disinfectant gel to evaluate the dissolution of a pharmaceutical form used for buccal use.

[0205] Again, after 20 minutes, the sample was completely dispersed, because no cream residue was present in the basket. Both formulations therefore have a dissolution time of 20 minutes.

[0206] Table 2: Dissolution values A on full cream over time. The SD values are all in the range ± 0.01 -0.02.

[0207] A further dissolution study on the cream containing the corticosteroid involves the B "dissolution" test, which consists of monitoring the release of the active ingredient over time from the basket wherein 1g of cream has been placed.

[0208] This experiment was conducted at a temperature of 37°C for a duration of 30 minutes both on the freshly prepared formulation and on the one stored for 14 days; the data obtained are shown in figure 3. From this experiment, it can be concluded that 100% of the drug becomes available in the external medium after 30 minutes, both for the freshly prepared cream and for the one stored for 14 days at 4°C. The process of releasing the active ingredient from the pharmaceutical form probably continues even after it is no longer present in the basket (20 minutes). From this comparison, it can be said that the cream based on Chios mastic is characterized by the same ability to release the active ingredient even after the storage period at 4 °C.

[0209] The inventors subsequently investigated the muco-adhesive capabilities of the composition. The muco-adhesion of the samples is studied by adhesion testing. The experiment is performed both on empty cream and on those containing corticosteroid (25°C and 4 °C), comparing it with a formulation for buccal use, with MA, i.e. Clobesol® cream (clobetasol propionate 0.05%).

[0210] 5 This experiment allows us to calculate the percentage of formulation adhered by means of the formula: formulation stuck after tilting (g)

[0211] % adherent formulation = - xl 00 formulation deposited on the mucin layer (gr)

[0212] 10 The experiment is performed as detailed in the examples by taking measurements at 6 min, 30 min and 1 hour.

[0213] As can be seen from the values shown in table 3, both empty and full creams have high percentages of mucus-adhesion (about 85% for both) even after 30 minutes from the start of the experiment. On the contrary, the Clobesol® cream after 30 15 minutes has an adhesion rate of about 13%.

[0214] It can therefore be concluded that the resin-based formulation could remain on the lesion in vivo for longer than the one currently on the market, with a consequent greater probability that the released drug could remain on the lesion.

[0215] 20 Table 3: Muco-adhesion test values on empty, full and comparison cream. The SD values are all in the range ± 0.01 - 0.02.

[0216] The same result is highlighted by the graph in figure 4. In light of the good results obtained, muco-adhesion experiments of the corticosteroid cream were carried out to observe whether its muco-adhesive capacity varied due to storage 25 conditions. Measurements were performed on both the cream stored at 25 °C and the cream stored at 4°C, over the course of 14 days on a weekly basis.

[0217] Comparing the data obtained from day 1 and 14, reported in tables 4 and 5 it can be seen that the mucus-adhesion capacity was the same even after the storage period at both temperatures; in fact, the percentage of formulation adhered to the slide was still 85% after 30 minutes.

[0218] Table 4: Values of the muco-adhesion test on full cream stored at 25° over time. The SD values are all in the range ± 0.01-0.02.

[0219] Table 5: Values of the muco-adhesion test on full cream stored at 4° over time. The SD values are all in the range ± 0.01-0.02.

[0220] Stability studies of the high-viscosity empty cream were also performed over the course of 4 weeks at different temperatures (25°C and 4°C), monitoring the appearance.

[0221] This study was carried out by storing equal aliquots of the aforementioned samples in tightly closed porcelain capsules (protected from light and air) at different temperatures. The measurements were carried out every day during the first week of storage and, subsequently, on a weekly basis.

[0222] Visual stability studies of corticosteroid-containing cream were performed over the course of 4 weeks at different temperatures (25°C and 4°C), monitoring appearance. This study was carried out by storing equal aliquots of the aforementioned samples in tightly closed porcelain capsules (protected from light and air) at different temperatures.

[0223] The measurements were carried out every day during the first week of storage and, subsequently, on a weekly basis. For both samples (with and without the drug), it is observed that the composition maintains stability at room temperature for at least 14 days. On the 14th day, a beginning of phase separation is observed with consequent inhomogeneity of the formulation. This phenomenon, instead, occurs around the 21st day of storage for the formulation stored at a temperature of 4 °C.

[0224] The stability of the corticosteroid cream is also observed by monitoring its weight to assess any evaporation of the aqueous phase.

[0225] Weight measurements of corticosteroid cream were also taken over the course of of 4 weeks at different temperatures (25°C and 4°C) on a weekly basis and the data collected are shown in Figure 5.

[0226] This study was carried out by keeping equal aliquots of the aforementioned samples in porcelain capsules tightly closed (away from light and air) at different temperatures. For samples stored at room temperature, there is an initial weight loss from day 14, also in agreement with the results of visual stability. This phenomenon is probably due to the evaporation of water.

[0227] This weight loss, instead, is less evident for the sample stored at 4°C, although a more significant change in the appearance of the cream is visible from the 21st day of storage.

[0228] Stability studies of the free corticosteroid were performed over the course of 4 weeks at different temperatures (25°C and 4°C), monitoring the absorbance, measured at a wavelength of 239 nm by a dual-beam Perkin-Elmer Lambda 25 UV-vis spectrophotometer. This study was conducted by storing the corticosteroid solution (0.005%) away from light and air at different temperatures.

[0229] Absorbance measurements are carried out weekly for a total of 4 weeks.

[0230] As can be seen from the spectra in Figure 6 a, no corticosteroid degradation phenomena are observed over time when the sample is stored at 25°C. In fact, the absorbance peaks characteristic of the corticosteroid, collected at different time intervals, are qualitatively similar to each other and almost overlapping for the entire duration of the experiment. In particular, in table 6 the values relating to the concentration of the active ingredient obtained from each peak have been reported, and it can be asserted that the corticosteroid does not undergo any degradation phenomenon over time.

[0231] Similarly, the stability of the free corticosteroid was evaluated at the storage temperature of 4 °C, performing the experiment as described above.

[0232] Also in this case, observing the spectra Figure 6 a, and Table 7 with the concentrations of the corticosteroid, it can be concluded that the corticosteroid does not undergo any degradation phenomenon over time even when stored at a temperature of 4 °C.

[0233] Table 6: Values of the concentration of free corticosteroid at 25° over time. The SD values are all in the range ±0.01-0.02.

[0234] Table 7: Free corticosteroid concentration values at 4° over time. The SD values are all in the range ± 0.01-0.02.

[0235] Stability studies of the corticosteroid (0.05%) incorporated into the cream were performed over the course of 4 weeks at different temperatures (25°C and 4°C), monitoring the absorbance, which is measured by a dual-beam Perkin-Elmer Lambda 25 UV-vis spectrophotometer.

[0236] This study was carried out by storing equal aliquots of the aforementioned samples in tightly closed porcelain capsules (protected from light and air) at different temperatures. The measurements were carried out on a weekly basis.

[0237] The stability of the corticosteroid inside the cream at 25°C is studied, as described above, by monitoring over time the peak absorption (wavelength 239 nm) of the corticosteroid (0.05%) present in the cream.

[0238] Absorbance measurements are carried out weekly for total 4 weeks. The values of the concentrations shown in tables 8 and 9 are derived from the absorbance values. As can be seen from the data in the tables, no degradation phenomena of the corticosteroid present in the resin-based cream are observed until the 14th day of storage when the sample is stored at both 25°C and 4°C.

[0239] Table 8: Values of the concentration of the corticosteroid incorporated into the cream (stored at 25°). The SD values are all in the range ±0.01-0.02.

[0240] Similarly, the stability of the corticosteroid incorporated in the cream was evaluated at the storage temperature of 4 °C, performing the experiment as described above. Also in this case, observing table 16 with the concentrations of the corticosteroid, it can be concluded that the corticosteroid does not undergo any degradation phenomenon over time even when stored at a temperature of 4°C Table 9: Concentration values of the corticosteroid incorporated into the cream (stored at 4°). The SD values are all in the range ±0.01-0.02

[0241] The composition according to the invention can be used as a basis for making other formulations suitable for oral administration, as a non-limiting example it is possible to make gummy candies, chewing gum and lollipops.

[0242] GUMMY CANDIES

[0243] Medicated gummy candies represent one of the most promising and advanced dosage forms in paediatric therapy and for those patients who cannot chew and swallow solid oral dosage forms. To make these gummy candies, the inventors, before reaching the final formulation, carried out numerous tests to optimize the optimal quantities of components, and in particular, vegetable glycerol 85% ph. eur. and animal gelatine powder 120 bloom to add to the cream to give the gummy candies the desired chewy texture. Initially, a unit ratio of glycerol to gelatine (1: 1) was used, but in this case the gummy candies obtained were too liquid in consistency.

[0244] Subsequently, the relative amount of glycerol was decreased. However, even in this case the gummy candies obtained did not have the desired appearance and consistency; in fact, they were too inhomogeneous due to the excessive presence of gelatine that did not allow adequate processing.

[0245] Therefore, an attempt was made to reverse the ratios of glycerol and gelatine, using an amount of 3.5 g of 85% vegetable glycerol and 1.7 g of animal gelatine powder. At this point, the gummy candies were found to be of adequate consistency for therapeutic purposes, flavoured and mucoadhesive, also thanks to the presence of gelatine.

[0246] It's important to underline that the optimized formulation process involves adding glycerol and gelatine hot once the cream is prepared. Before combining and mixing the different components, it was necessary to hydrate the gelatine powder with the minimum amount of preserved water, then melt the gelatine in a container, and, when melted, add glycerol and the cream according to the invention. Following the union of the various components, it was necessary to carefully mix the semi-liquid mixture to make it homogeneous before pouring it into the moulds.

[0247] The preparation of gummy candies takes place by following, as a result of the preparation of the cream, the following basic steps • Mixing the powdered gelatine with the water stored in a suitable container,

[0248] • Placing the container in a bain-marie on a griddle at about 65 °C until the animal gelatine melts

[0249] • Adding an aliquot of previously prepared base cream and mixing

[0250] • Adding the vegetable glycerol 85% to the preparation placed at 65 °C • Stirring to obtain a homogeneous mixture, pouring everything into the moulds and placing them at 4°C after cooling to room temperature.

[0251] The gummy candies according to the invention comprise: In a preferred embodiment, gummy candy comprises:

[0252] Substance Quantity

[0253] Tween 80 1.385 g

[0254] Chios mastic 1,200 g

[0255] Clobetasol 0.018 g Preserved water 1.00 ml

[0256] Orange flavour 0.50 g

[0257] Animal Gelatine Powder 1-70 g

[0258] Vegetable glycerol 85% 3.50 g

[0259] Following the preparation of the medicated gummy candies, several tests were performed to evaluate the overall stability of the formulation and the drug within it, for a total period of 4 weeks. Stability studies were performed at different temperatures (25 °C and 4°C) of the gummy candy without active ingredient and of the one containing an active ingredient, specifically a corticosteroid, clobetasol.

[0260] The results show excellent stability, in terms of appearance, of both formulations, when stored at 4°C.

[0261] Formulations stored at 25°C take on a different color from day 14. This behaviour is attributable to a possible oxidation of the components.

[0262] In a preferred embodiment, gummy candies additionally contain antioxidant agents and / or preservatives from those listed below:

[0263] • Preserved water

[0264] • Methyl para hydroxybenzoate (Sodium nipagin)

[0265] • Propyl para hydroxybenzoate (Sodium nipasol)

[0266] • Ascorbic acid

[0267] • Sodium erythorbate

[0268] • Citric acid

[0269] Among the antioxidant agents listed, the one selected is shown in the table, i.e. preserved water, whose composition is reported.

[0270] Substance Quantity

[0271] Sodium nipasol 0.25 g

[0272] Sodium nipagin 0.75 g

[0273] Highly purified water q.s. to 1 1 Stability studies were also conducted by monitoring the change in weight over time, in order to evaluate possible evaporation phenomena of the aqueous phase. The results obtained are shown in Figure 7.

[0274] Again, gummy candies stored at room temperature seem to be less stable than those stored at 4°C. In fact, as observed in Figure 7, the former are characterized by a significant weight loss already after the first week, which becomes even more significant in the following weeks. Such weight loss could be attributed to a possible loss of water. On the contrary, gummy candies stored at a temperature of 4°C prove to be stable in terms of weight, which is constant over time. Probably, therefore, the most suitable storage temperature is 4°C, because it is able to inhibit degradation processes of the components. A similar behaviour is evident with the formulations containing the active ingredient, which were found to be stable only at the storage temperature of 4 °C.

[0275] In order to evaluate whether the inclusion of the active ingredient in the gummy candy could induce degradation and / or destabilization phenomena, stability studies were performed for 30 days at 25°C and 4°C, also monitoring the intensity of the characteristic peak of the molecule (absorbance detected at 239 nm), as shown in the spectra shown in figure 8 panel A and B

[0276] From the data reported in Table 10 it can be observed that the concentration of the active ingredient contained in the gummy candy remains constant when it is stored at 4°C, a slight decrease in the concentration is observed when the formulation is stored at room temperature.

[0277] Probably the instability phenomena found at 25°C, already described in previous experiments (visual and weight stability), could also affect the stability of the active molecule.

[0278] Table 10: Concentration values of the corticosteroid incorporated in the gummy candy stored at 25°C and 4°C over 4 weeks.

[0279] The inventors have also performed dissolution studies on gummy candies. The study of dissolution was conducted on the basis of what is reported in Farmacopea Ufficiale Italiana, XII Ed, chapter 2.9.3. "Saggio di dissoluzione delle forme farmaceutiche solide" and made it possible to monitor, at established time intervals, a possible decrease in the weight of the gummy candy in the basket.

[0280] The experiment was conducted on both empty gummy candies and those containing the active ingredient.

[0281] It can be observed (Figure 9) that both formulations dissolve 100% at the end of the test in 20 minutes. In particular, the different formulations after 10 minutes show a percentage of dissolution ranging between 2% and 10%, after 15 minutes, the percentage is between 25% and 50%, finally, at the twentieth minute the gummy candies are all completely dissolved.

[0282] In order to verify whether the dissolution profile of the gummy candies, with and without drug at the two different temperatures, maintained the same trend also on the seventh, fourteenth, twenty-first and twenty-eighth days after preparation, the same dissolution test was carried out on a weekly basis. As can be seen in the graphs (Figures 10, 11, 12, 13), in all cases, the gummy candies are completely dissolved after 20 minutes, confirming that time does not affect the speed of dissolution.

[0283] In addition, what is observed is that candies stored at 25°C show a progressive decrease in weight at to on days 1, 7, 14, 21, 28, in accordance with the results obtained from weight stability shown in section 3.3.2. On the contrary, candies stored at 4 °C have constant weights at to.

[0284] A further dissolution study on candies containing the corticosteroid involved monitoring the release of the drug, over time, from the basket wherein the candy was placed. The data obtained are shown in the graph shown in Figure 14. From this experiment, it is clear that 100% of the active ingredient is present in the external medium after 30 minutes.

[0285] Finally, the muco-adhesion of candies was evaluated as described in the examples. Measurements were taken at 6 minutes, 30 minutes, and 60 minutes.

[0286] As shown in the graph (Figure 15), candies without medication and those with the drug have high percentages of mucus-adhesion. After about 30 minutes, there are percentages between 99.6% and 99.8% of muco-adhesion and after 60 minutes the percentages are between 99.6% and 99.7%. In the light of the results obtained, we can assert that the formulations have high mucoadhesive properties, which do not depend on storage conditions.

[0287] CHEWING GUM

[0288] Medicated chewing gum is one of the most effective forms of medication for administering active ingredients into the buccal cavity. The gums can be taken without water and at any time and their use is extremely advantageous in the treatment of patients with difficulty in swallowing.

[0289] Medicated chewing gum is a single-dose solid preparation with a base consisting essentially of gum, intended to be chewed but not swallowed. The production of gum involves the use of a tasteless chewing gum base, consisting of natural or synthetic elastomers. Gums can also contain other excipients such as flavourings, stabilizers, etc.

[0290] They contain one or more active ingredients that are released with chewing.

[0291] The inventors have managed to obtain an elastic formulation, persistent to chewing and with a homogeneous appearance.

[0292] As with medicated candies, also for medicated gums, the base of the formulation process is the preparation of the base cream described above.

[0293] To obtain the final formulation, other essential components were added to 3 g cream: a base gum (the commercial gum base used is composed of: 33-37% base gum, sorbitol 4-8%, anti-packing agent (E 551) < 2%, isomalt up to 100%) and a plasticizer (sucrose powder). The main difficulty was to understand what the optimal quantities were to obtain a gum that is easily workable and with a compact and rubbery consistency when chewed.

[0294] Medicated gums according to the invention comprise:

[0295] In a preferred embodiment, the chewing gums comprise:

[0296] The optimized formulation process provides that, following the preparation of the base cream, with or without active ingredient, 4.00 g of hot base gum is added, mixing it thoroughly with the help of a spatula and placing everything in a bain- marie (65 °C). Once a homogeneous and elastic mixture has been obtained, the cold plasticizer (5.00 g) is added, and the gum mass is processed to give it the desired shape.

[0297] To make the consistency of the gum more compact, it is stored at 4°C before use.

[0298] Month-long stability studies were performed on medicated gum without active ingredient and corticosteroid-containing gum at room temperature and 4°C and monitored for appearance. The gums were stable at both 25°C and 4°C over the course of the 4 weeks.

[0299] As a further preliminary stability study, the change in terms of weight of the gums, with and without medication, for 30 days was evaluated. It has been observed that gums stored at room temperature and those stored at 4°C maintain optimal weight stability over the 4 weeks (Figures 16 and 17). Therefore, it can be said that storage conditions do not affect stability, in accordance with visual stability studies.

[0300] HARD CANDIES, LOLLIPOPS, LOZENGES

[0301] Lollipops and hard candies and sucking lozenges are a solid pharmaceutical form designed to slowly dissolve in the oral cavity releasing a constant amount of medication.

[0302] According to the invention, these are prepared by mixing the base cream with or without the active ingredient with a sweetened and flavoured base, but they can also contain preservatives, mattifiers and stabilizers.

[0303] These embodiments according to the invention comprise:

[0304] In a preferred embodiment they comprise: The preparation takes place by following, as a result of the preparation of the cream, the following basic steps

[0305] • Dissolving the sucrose aliquot in 1.00 ml of water;

[0306] • Adding 0.60 ml of liquid orange flavouring and 0.60 ml of water to this solution; • Adding the cream to the just obtained solution and making the mixture homogeneous

[0307] • Pouring everything into the moulds and placing them at 4°C after cooling.

[0308] CLINIC Patients in the trial provided free and informed consent to treatment. Patients suffering from oral lichens planus, histologically diagnosed after cold blade biopsy, resistant to conventional drug therapies (galenic preparation of clobetasol 0.05% adhered to a 4-hydroxyethylcellulose vehicle suitable for oral application) were selected.

[0309] Before starting therapy, patients had erythematous flat lesions associated or not with whitish hyperkeratotic striae and areas of atrophic mucosa or with small shallow ulcers. Patients were treated as detailed in the examples.

[0310] In an exemplary case, in the intra-oral picture (Figure 18) we can observe the region of the hard palate of one of the patients participating in the trial. On the middle third of the right hemipalate there is an area of mucosa that corresponds to the typical appearance of the atrophic Lichen Planus that has not yet been treated. In the second picture (Figure 19) it is possible to appreciate the clear reduction in the extension of the lesion, a return of the mucosa to its physiological pink color and reduction of hyperkeratotic striae. The same patient said he had a reduction in irritative symptoms and sensation of roughness to the touch.

[0311] EXAMPLES

[0312] Morphological characterization

[0313] The preparations with and without the active ingredient were analysed using an optical microscope.

[0314] An optical microscope is a type of microscope that uses light with wavelengths from near infrared to ultraviolet, covering the entire visible spectrum.

[0315] The images were obtained in collaboration with Dr. Mariagrazia Ammendolia, at Centro Nazionale Tecnologie Innovative in Sanita Pubblica, Istituto Superiore di Sanita (ISS), Rome, Italy.

[0316] The method used is that of brightfield optical microscopy: a drop of each sample (cream without and with corticosteroid) was placed on a slide, covered with a coverslip and immediately observed using a transmitted light optical microscope (Leica DM4000, Leica Microsystem, Wetzlar, Germany), using a 40x magnification objective. The images were captured with an FX 340 digital camera associated with the microscope.

[0317] Formulation studies The inventors have developed a comparative test to evaluate the influence of surfactant on the stability and homogeneity of the composition of the invention. The surfactants have been appropriately selected from the class of neutral surfactants, i.e. amphiphilic compounds with non-ionizable polar groups. This allowed for a direct comparison between compounds that had the same electric charges in their hydrophilic heads. Within this class of neutral surfactants, two surfactants with a different distribution of lipophilic / hydrophilic moieties (organic fragments) were selected:

[0318] • Tween 80 (Polysorbate 80 or Polyoxyethylene (20) sorbitan monooleate), hydrophilic surfactant with an HLB value of about 15;

[0319] • Span 65 (Sorbitan tristearate), lipophilic surfactant with an HLB value of about 2.

[0320] The base cream according to the invention was prepared according to the method mentioned above. In particular, the following steps have been carried out:

[0321] The Chios mastic (2.400 g) was initially pulverized with the help of a mortar and pestle. The powder obtained was deposited in the sieve 0200 mm Mesh size 0.315 mm (DIN 4188), then placed back on top of the lid. The sieve column was shaken for 5 min, carefully separating the sieve from the column to prevent substance loss. Two separate containers were then prepared for the preparation of the two samples. In the first container (Cl), 1.200 g of the resulting Chios mastic powder was mixed with the surfactant tween 80 (1.385 g). In the second container (C2), the other 1.200 g of Chios mastic powder was mixed with Span 65 (1.385 g). Both samples Cl and C2 were mixed until a homogeneous paste was obtained. At this point, distilled water was added in a 1 : 1 ratio and the mixture obtained was mixed again until a final mixture was obtained. Already at this level, the inventors observed that the lipophilic and aqueous phases of the C2 sample showed great difficulty in homogenization, a problem not found in the Cl sample.

[0322] The two compositions Cl and C2 were then subjected to the action of a sonicator at a temperature of 65°C, amplitude 25%, for a time of 15 min. The two samples were cooled to room temperature.

[0323] Table 11 below and Figures 22,23 to which they refer clearly highlight the difference in emulsifying power between the two surfactants tested.

[0324] Table 11: Comparative formulation test

[0325] Firstly, the visual appearance of samples prepared with different surfactants is significantly different. The Cl composition is macroscopically homogeneous, with an adhesive consistency to the touch, while the C2 composition appears inhomogeneous, not very cohesive and grainy in appearance. This result indicates that the mere presence of a surfactant is not in itself sufficient to guarantee the stability and desired properties of the formulation: it is necessary to select a surfactant with specific chemical-physical characteristics, capable of giving homogeneity, adhesiveness and cohesion to the mixture. Even in the presence of a similar surface charge (both without explicit charges), variations in the location and concentration of the residual polar groups within the surfactant structure significantly influence the architecture of the final composition. The influence of the chemical-physical properties of the surfactant appears so marked that the use of a surfactant with an HLB value of less than 10 is inadequate to ensure an effective stabilization of the mixture.

[0326] Dissolution Studies

[0327] Simulated saliva

[0328] For the studies carried out in order to evaluate the possible "dissolution" of the formulation, as well as to carry out stability studies, an artificial saliva, similar in composition to that of humans, was prepared in order to mimic the conditions in vivo, in the hypothesis of administration.

[0329] The preparation of 1 liter of simulated saliva involves: 1. weighing the listed components with the technical balance, according to the following quantities:

[0330] Table 12: Substances used for the preparation of simulated saliva.

[0331] 2. placement of the weighed substances inside a 1 -liter flask and addition of distilled water up to 500 mL;

[0332] 3. insertion of a magnet inside the flask, start of magnetic stirring for at least 12 hours, during which time it is necessary to check that the pH falls within the physiological salivary pH range (between 5.8-7.4). If necessary, the preparation will be acidified using a solution formed by fuming hydrochloric acid in distilled water (1: 100);

[0333] 4. Addition of distilled water up to volume, once the correct pH has been verified.

[0334] This preparation is stable for up to 30 days, stored at a temperature of 25°C, away from light and heat sources.

[0335] Dissolution test method A: "dissolution time” ofcream

[0336] The process of dissolution of the samples has been studied by means of the "dissolution test A", which consists of an experiment that follows in the footsteps of the dissolution assay of Farmacopea Ufficiale Italiana XII Ed. (chapter 2.9.3. "Saggio di dissoluzione delle forme farmaceutiche solide").

[0337] 1g of cream was placed inside a basket immersed in a system that could recreate buccal physiological conditions, i.e. a beaker containing 250 ml of simulated saliva at 37 ± 0.5°C under magnetic stirring at 100 rpm; in this way, the weight of the basket is measured at predetermined time intervals (t=0, 5 min, 10 min, 20 min). In this way, it was possible to calculate the percentage of dissolution of the cream over time.

[0338] Dissolution test method B: quantification of the active ingredient in the cream

[0339] The phenomenon of dissolution is also studied by means of the " dissolution test B ", which consists of monitoring the release over time of corticosteroid from the basket wherein 1g of cream has been placed.

[0340] This experiment involves immersing the sample in 250 ml of saliva solution kept under stirring (100 rpm) at 37°C (±0.5°C), to simulate the conditions of a buccal administration; every 5 minutes, for a total of 30 minutes, approximately 1ml was taken from the external medium to monitor the characteristic absorbance of the corticosteroid released by the cream and, therefore, present in the external phase.

[0341] A Perkin-Elmer, Lambda 25 UV-vis dual-beam spectrophotometer is used, which allows simultaneous reading of the sample and a reference standard.

[0342] This instrument exploits ultraviolet / visible spectroscopy, a spectroscopic molecular absorption technique, whereby when an ultraviolet or visible photon is absorbed by the molecule, it passes from a fundamental electronic state to an excited state.

[0343] The concentration is determined through the use of the calibration line, constructed through measurements of the absorbance of solutions of known concentration.

[0344] The calibration line (also called calibration curve) is a method for determining the concentration of an unknown sample by interpolation.

[0345] In order to be able to interpret the experimental data, there must be a linear relationship between the concentration and the response of the instrument, which in this case is the absorbance measured by a dual-beam Perkin-Elmer Lambda 25 UV-vis spectrophotometer.

[0346] Given x the concentration of the analyte and y the absorbance, it is necessary to obtain a line of equation y = mx+n, wherein m is the angular coefficient and n the intercept. The calibration line is constructed by measuring the absorbance of solutions at known concentrations of corticosteroid, which absorb at a wavelength of about 239 nm.

[0347] The absorbance, obtained from the analysis of the volume of sample taken from time to time, is directly related to the concentration of drug present in the sample, in accordance with the Lambert-Beer law.

[0348] .4 £ • / ■ C

[0349] Thus, the absorbance (A) is directly proportional to:

[0350] • molar absorption coefficient (a), is a quantity that depends on the type of solvent, the wavelength used and the chemical species that gives the absorption, while it is independent of temperature;

[0351] • optical path ( / ), is the thickness of the solution contained in the cuvette that is crossed by light;

[0352] • concentration of the solution (C).

[0353] The corticosteroid calibration line is constructed by preparing the stock solution containing 0.05% clobetasol.

[0354] From the stock solution, the different solutions with different dilutions are obtained, the absorbance values of which are measured.

[0355] Dissolution test method A: Dissolution Time of "Medicated Gummy candies”

[0356] The dissolution assay of medicated gummy candies was conducted on the basis of the parameters indicated by the Farmacopea Ufficiale Italiana XII Ed. (chapter 2.9.3. "Saggio di dissoluzione delle forme farmaceutiche solide").

[0357] A gummy candy was placed inside a basket immersed in a system that could recreate buccal physiological conditions, therefore, a beaker containing 250 mL of simulated saliva at 37 °C ± 0.5 was used. The simulated saliva was placed under magnetic stirring at 100 rpm.

[0358] At predetermined time intervals (t=0, 5 min, 10 min, 20min) the basket is picked up, with the gummy candy inside, and weighed. In this way, it was possible to calculate the percentage of gummy candy dissolution over time based on a measure of weight loss.

[0359] Dissolution test method B: quantification of the active ingredient A different type of test was performed to verify the dissolution of the gummy candy and, therefore, the release of the active ingredient into the external medium.

[0360] In this experiment, the gummy candy was immersed and dissolved in 250 mL of simulated saliva solution kept under stirring (100 rpm) at 37°C ± 0.5, to simulate the conditions of a buccal administration.

[0361] A sampling of 1 mL was taken from the external medium every 5 minutes, for a total of 30 minutes, and out of this taken portion the characteristic absorbance of the corticosteroid released from the gummy candy was measured.

[0362] The previously described dual-beam Perkin-Elmer Lambda 25 UV-Vis spectrophotometer was used to measure the absorbance.

[0363] Muco-adhesion studies

[0364] Muco-adhesion is the ability of a substance to remain adherent to a mucosal layer, thanks to the interaction with mucin.

[0365] Mucin suspension

[0366] 12% w / w mucin suspension is used for muco-adhesion studies. The preparation of 5 ml of 12% w / w mucin suspension is carried out using the following substances and their quantities,

[0367] Type II gastric mucin 0.600 g

[0368] Distilled water q.s. to 5 ml according to the following procedure: a) weigh type II gastric mucin inside a laboratory vessel with the technical balance; b) place the substance inside a 5 ml flask and bring to volume with distilled water; c) insert a small magnet inside the flask and put everything under magnetic stirring for about 2 hours.

[0369] This suspension will be readily used in order to avoid degradation of the test mucin. The muco-adhesion study of the high viscosity cream is carried out by means of the so-called "Adhesion Test" which consists of: a) homogeneously applying 1ml of 12% w / w mucin suspension on a slide; b) placing the loaded slide in the stove at 70°C for 45 minutes, in order to dry the mucin suspension and form a film (=mucin layer); c) once the mucin layer is formed, applying a layer of cream / whole high- viscosity gummy candy to the slide; d) placing the slide-mucin-cream system at 90°, so as to allow the excess of non-adherent formulation to slide; e) weighing the system at 6 min, 30 min and 1 hour; f) calculating the percentage of formulation adhered to at 6 min, 30 min and 1 hour. formulation stuck after tilting (gr)

[0370] % adherent formulation = - xlOO formulation deposited on the mucin layer (gr)

[0371] The muco-adhesion study of medicated gummy candies was carried out by means of the so-called "Adhesion Test" which involves the following steps:

[0372] • homogeneously applying 1 mL of 12% by weight mucin suspension to a slide;

[0373] • placing the mucin-covered slide in a stove at 70°C for 45 minutes in order to dry the mucin suspension and form a film (mucin layer);

[0374] • applying the candy on the slide, once the mucin layer has formed;

[0375] • arranging the slide-mucin-candy system in such a way that the movement of the candy on the slide can be visualized. Therefore, the slide is positioned at 90° with respect to the support surface;

[0376] • weighing the system at 6 min, 30 min and after 1 hour;

[0377] • calculating the percentage of formulation adhered to at 6 min, 30 min and 1 hour.

[0378] Corticosteroid stability studies In order to evaluate whether the corticosteroid contained in the cream remained stable during the storage period, measurements of the absorption of the corticosteroid alone and of the corticosteroid incorporated in the cream in the formulation were performed, using the UV spectrophotometer (Perkin-Elmer Lambda 25 UV-vis dual-beam spectrophotometer) also used in the dissolution B test.

[0379] The corticosteroid calibration line is constructed by preparing the stock solution, which is a solution with 0.05% corticosteroid.

[0380] From the stock solution, the different solutions at different concentrations are obtained and the absorbance values are measured thanks to the use of the UV spectrophotometer (Perkin-Elmer Lambda 25 UV-vis double-beam spectrophotometer) .

[0381] Stability studies of the free corticosteroid were performed over the course of 4 weeks at different temperatures (25°C and 4°C), monitoring the absorbance, which is measured by a dual-beam Perkin-Elmer Lambda 25 UV-vis spectrophotometer. The absorbance obtained is directly related to the concentration of the corticosteroid in the analysed phase, in relation to the Lambert-Beer law.

[0382] The concentration is determined through the use of the calibration line, previously constructed through measurements of the absorbance of solutions with known concentration.

[0383] This study was conducted by storing corticosteroid solutions (0.005%) away from light and air at different temperatures, carrying out measurements on a weekly basis.

[0384] Stability studies of the corticosteroid (0.05%) incorporated into the cream were performed over the course of 4 weeks at different temperatures (25°C and 4°C), monitoring the absorbance, which is measured by a dual-beam Perkin-Elmer Lambda 25 UV-vis spectrophotometer.

[0385] The absorbance obtained is directly related to the concentration of the corticosteroid in the analysed phase, in relation to the Lambert-Beer law. The concentration is determined through the use of the calibration line, previously constructed through measurements of the absorbance of solutions with known concentration.

[0386] This study was carried out by storing equal aliquots of the aforementioned samples in tightly closed porcelain capsules (protected from light and air) at different temperatures.

[0387] The measurements were carried out on a weekly basis by taking a small, solubilized aliquot from the stored cream and then analysing with a spectrophotometer.

[0388] The stability of the corticosteroid (0.05% by weight) present in the medicated gummy candy, stored at different temperatures (25°C and 4°C), was evaluated by carrying out tests on a weekly basis for 4 weeks. The measurements were carried out by dissolving the gummy candy in the external phase and taking a small, solubilized aliquot and then analysing it.

[0389] The tests were conducted by monitoring the absorbance, measured by a Perkin- Elmer Lambda 25 UV-Vis dual-beam spectrophotometer. The absorbance obtained is directly related to the concentration of the corticosteroid in the analysed phase, in relation to the Lambert-Beer law. The concentration is determined through the use of the calibration line previously constructed through measurements of the absorbance of solutions of known concentration.

[0390] This study was conducted by storing the samples in well- sealed porcelain capsules, protected from light and air, at different temperatures.

[0391] Clinical trial

[0392] The clinical trial of the drug involved the participation of an initial group of three patients diagnosed with atrophic / erosive Lichen Planus. Candidate patients, male and female between the V-VI decade of life, showed symptoms of generic impairment of oral functions caused by burning and tingling sensations throughout the mouth and, above all, were resistant to conventional drug therapies (galenic preparation of clobetasol 0.05% adhered to a vehicle of 4- hydroxy ethylcellulose suitable for oral application). On intra-oral inspection, they showed lesions typical of the pathology, i.e. areas of diffused erythematous mucosa in the buccal, gingival and hard palate regions. Within these areas, the characteristic Wickham's striae, i.e. whitish hyperkeratotic striae with an arborescent appearance from which the lichen planus pathology acquires its name (similar to lichens) were often found.

[0393] In specific cases, the pathology also takes on an atrophic erosive character for which small shallow ulcerated areas are found in the context of the lesion. This aspect confers a higher risk of malignant transformation (Figure 20).

[0394] Two 20-day cycles of therapy were administered for each patient consisting of 7 days of oral drug intake followed by 3 days off. Patients were instructed by the clinician on the correct way to take the drug. The candy was melted in the mouth by the patient, taking care to keep it adherent to the lesions and avoiding biting, crushing or swallowing it. Generally, already at the first check-up in progress after the first cycle, the lesions were slightly smaller and less erythematous, even if the sensory symptoms persisted in a less pronounced way. After the end of the second cycle, in general we noticed the progressive reduction of both the erythematous areas and the associated symptoms (Figure 21). In one case, however, a typical corticosteroid side effect symptomatology was found characterized by the appearance of erythema on the face and easy irritability. In general, patients were satisfied with the new therapeutic modality, with regard to the better and easier applicability of the product at the level of oral lesions, the prolonged persistence, the long-term effects.

Claims

CLAIMS1. A mucoadhesive composition comprisingAn aliquot of Chios masticOne or more non-ionic surfactants, having a total HLB greater than 10, preferably selected from the group of polysorbates, sorbitan esters and polyoxyethylenes and mixtures thereofA flavor;Water, preferably preserved water.

2. The composition according to claim 1 further comprising at least one pharmacologically active ingredient for the treatment of mucocutaneous diseases of the oral cavity.

3. The composition according to claim 2 wherein the pharmacologically active ingredient is selected from steroidal or non-steroidal anti-inflammatory agents, steroids and corticosteroids, analgesics and local anesthetics, antibiotics, antifungals, antivirals, antiseptics, bactericides, healing agents, keratolytic and re- epithelializing agents and mixtures thereof.

4. The composition according to one of claims 2 or 3 wherein the active ingredient is selected from Clobetasol, Chlorhexidine, Fluocinonide, Aciclovir, Nystatin, Miconazole and mixtures thereof.

5. The composition according to anyone of claims 2-4 wherein the active ingredient is clobetasol, preferably clobetasol propionate at a final weight % of 0.05%.

6. The composition according to anyone of the preceding claims wherein the surfactant is selected from polyoxyethylene (20) sorbitan monolaurate, polyoxyethylene (4) sorbitan monolaurate, polyoxyethylene (20) sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate and mixtures thereof.

7. The composition according to claim 6 wherein the surfactant is polyoxyethylene (20) sorbitan monooleate.

8. The composition according to anyone of the preceding claims further comprising a preservative selected from preserved water, methylparahydroxybenzoate, sodium nipagin, propyl parahydroxybenzoate, sodium nipasol ascorbic acid, sodium erythorbate, citric acid and mixtures thereof.

9. The composition according to anyone of the preceding claims wherein the flavor is a powder flavor selected from caramel orange, lemon, orange, vanilla, grapefruit, tangerine, lime, strawberry and cherry, preferably orange flavor.

10. The composition according to anyone of the preceding claims comprisingChios mastic in an amount between 1.00 and 1.2 g, a surfactant preferably polyoxyethylene (20) sorbitan monooleate in an amount between 1.35 - 1.40 g a pharmacologically active ingredient, preferably clobetasol propionate, in an amount between 0.01 and 0.02 g water, preferably preserved water, in an amount between 1.00 and 2.00 ml a flavor, preferably orange flavor in an amount between 0.40 and 0.60 g.

11. The composition according to claim 10 comprising:Chios mastic in an amount of 1.2 g,Polyoxyethylene (20) sorbitan monooleate in an amount of 1.385 gClobetasol propionate in an amount of 0.018 gPreserved water, in an amount of 1.00 mlOrange flavor in an amount of 0.5 g.

12. The composition according to anyone of the preceding claims in the form of a cream.

13. Formulation comprising the composition according to any one of claims 1-12 and at least one additive selected from sucrose, animal gelatine powder, vegetable glycerol 85%, gum base, plasticizing element.

14. Formulation according to the preceding claim in the form of a gummy candy comprising animal gelatine powder and vegetable glycerol 85%.

15. Formulation according to claim 13 in the form of chewing gum comprising gum base and a plasticizing element, preferably powdered sucrose.

16. Formulation according to claim 13 in the form of a lozenges, hard candies or lollipops, said formulation comprising sucrose.

17. A process for preparing the composition according to anyone of claims 1-12 comprising the following basic steps:Pulverizing an aliquot of Chios mastic in the form of drops and sifting the powder;Mixing the resulting Chios mastic powder with the surfactant until a homogeneous paste is obtained;Adding distilled water, preferably preserved water, preferably in a 1: 1 ratio;Mixing until a homogeneous mixture is obtained;Subjecting the mixture to the action of a sonic ator;After sonication, adding the flavor, preferably in the form of powder, optionally adding the at least one pharmacologically active ingredient, and mixing until a homogeneous mixture is obtained and pouring into a suitable container for storage;Cooling at room temperature;Storing preferably at 4°C after cooling.

18. The composition according to any one of claims 1 to 12 or formulation according to any one of claims 13 to 16 for use in the treatment of mucocutaneous conditions of the oral cavity in animals and humans, including the elderly, infants and children.

19. The composition according to any one of claims 1 to 12 or formulation according to any one of claims 13 to 16 for use according to claim 18 wherein the condition is selected from Oral lichen planus, Lichenoid lesions, Oral lesions from GVHD, Congenital epidermolysis bullosa, Acquired epidermolysis bullosa, Pemphigus, Pemphigoid, Aphthosis minor and major, Oral manifestations of Lupus Erythematosus, Stomatitis, Atrophic-erosive and ulcerative lesions of various nature.

20. The composition according to any one of claims 1 to 12 or formulation according to any one of claims 13 to 16 for use in the treatment of Lichen planus.

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