RAPAMYCIN-CONTAINING PHARMACEUTICAL COMPOSITION

Abstract

The present invention relates to a stable rapamycin-containing composition for the treatment of skin diseases, a method for producing the same, a method for stabilizing the same and a method for inhibiting the decomposition of rapamycin.

Description

Technical field

[0001] The present invention relates to a stable rapamycin-containing composition for the treatment of skin diseases, a method for its preparation, and a method for its stabilization. Furthermore, the invention relates to a method for inhibiting the decomposition of rapamycin in the rapamycin-containing composition for the treatment of skin diseases.

[0002] The present invention also relates to a technique for improving the transdermal absorption of a rapamycin-containing composition for the treatment of skin diseases. Specifically, the invention relates to a composition in which the transdermal absorption of the active ingredient, rapamycin, is improved by adjusting the concentration of ethanol contained in the composition within a specific range, a method for improving the transdermal absorption of a rapamycin-containing composition for the treatment of skin diseases, and a method for producing a rapamycin-containing composition for the treatment of skin diseases in which the transdermal absorption of rapamycin is improved. State of the art

[0003] Rapamycin (generic name: sirolimus), a metabolite of the actinomycete Streptomyces hygroscopicus, is known to inhibit the action of the mammalian target of rapamycin (mTOR), which regulates cell division, growth, and survival. mTOR is known to be permanently activated in various diseases, such as tuberous sclerosis complex (TSC), and rapamycin can be used as a therapeutic agent for these diseases by inhibiting mTOR activity. (R. Balestri et al., Journal of the European Academy of Dermatology and Venereology, 2015, vol. 29, pp. 14-20).

[0004] TSC is associated with angiofibromas and other skin diseases, and topical application of rapamycin to the affected area is an effective way to treat TSC with minimal side effects. It is necessary to combine rapamycin dissolved in a solvent with a base material, such as a gel or ointment, to use rapamycin in a topical application. However, rapamycin is unstable in aqueous solvents.

[0005] Additionally, a stabilization technique is disclosed in which an antioxidant is added to an inert solvent solution to precipitate the mixture in order to improve the stability of a rapamycin derivative (40-O-(2-Hydroxy)ethyl-rapamycin) against oxygen during the isolation process (JP Patent No. 3805625). Summary of the invention: Technical problem

[0006] One object of the present invention is to provide a stable rapamycin-containing composition for the treatment of skin diseases (gel formulation), a method for producing the same, and a method for stabilizing it. Another object of the present invention is to provide a method for inhibiting the decomposition of rapamycin in the rapamycin-containing composition for the treatment of skin diseases. A further object of the present invention is to provide a method for stabilizing the rapamycin-containing composition for the treatment of skin diseases and a method for inhibiting its decomposition.

[0007] On the other hand, for topical formulations used to treat skin diseases, it is important that the active ingredient, rapamycin, is sufficiently absorbed through the skin to reach the affected area. To date, no methods for improving this transdermal absorption have been disclosed.

[0008] The present invention was achieved in light of the foregoing circumstances and provides a rapamycin-containing composition for the treatment of skin diseases (gel formulation) with improved transdermal absorption. It is also an object of the present invention to provide a method for improving the transdermal absorption of a rapamycin-containing composition for the treatment of skin diseases. Solution to the problem

[0009] The present invention relates to a process for producing a rapamycin-containing composition for the treatment of skin diseases, comprising the steps of dissolving rapamycin in an ethanol-containing solvent, adding a gelling and / or thickening agent to the resulting rapamycin-containing solution, and adjusting the pH of the resulting rapamycin-containing solution to 5.5 to 6.1.

[0010] The process for producing a rapamycin-containing composition for the treatment of skin diseases includes, in one embodiment, the step of adjusting the pH of the final composition to a range of approximately 5.5 to approximately 6.1. Such a process can inhibit the degradation of the main pharmaceutical ingredient, rapamycin, and improve its stability. Various studies have been conducted to stabilize rapamycin-containing compositions, but conditions sufficient to achieve the desired effects have not been found. The inventors have found that the rapamycin-containing composition can be stabilized by a simple process such as controlling the pH within a specific range, thus achieving the present invention.

[0011] The process for manufacturing a rapamycin-containing composition for the treatment of skin diseases involves, in one embodiment, mixing rapamycin and ethanol in an amount that results in a concentration of 40-50% by weight in the composition. Such a process can improve the transdermal absorption of a rapamycin-containing composition for the treatment of skin diseases.

[0012] Since rapamycin is nearly insoluble in water, when incorporated into gel formulations, it was previously dissolved in a solvent, such as ethanol, and mixed with the base compound. This meant that in gel formulations containing rapamycin, the ethanol was merely a necessary ingredient for dissolving the rapamycin, and no studies had been conducted to investigate the relationship between the ethanol and the transdermal absorption of the active ingredient. The inventors discovered that the transdermal absorption of rapamycin could be improved by adjusting the ethanol concentration in the gel formulation within a specific range, and thus completed the present invention.

[0013] The present invention relates to a method for stabilizing the rapamycin-containing composition for the treatment of skin diseases, comprising the step of adjusting the pH of the composition in a range of about 5.5 to about 6.1.

[0014] Furthermore, the present invention relates to a method for inhibiting the decomposition of rapamycin in the rapamycin-containing composition for the treatment of skin diseases, comprising the step of adjusting the pH of the composition in a range of about 5.5 to about 6.1.

[0015] The rapamycin-containing composition for the treatment of skin diseases of the present invention comprises, in one embodiment, rapamycin; and at least one pH adjusting agent selected from the group consisting of sodium hydroxide, sodium bicarbonate, triethanolamine, tris(hydroxymethyl)aminomethane; and to be a rapamycin-containing composition for the treatment of skin diseases with a pH of about 5.5 to about 6.1.

[0016] The rapamycin-containing composition for the treatment of skin diseases according to the present invention comprises, in one embodiment, rapamycin and ethanol; and is to be a rapamycin-containing composition for the treatment of skin diseases with an ethanol content in the range of 40-50% by weight of the composition. Such a structure can improve the transdermal absorption of rapamycin. Advantageous effects of the invention

[0017] The present invention can provide a rapamycin-containing composition for the treatment of skin diseases with reduced rapamycin degradation and stability.

[0018] The present invention can also provide a rapamycin-containing composition for the treatment of skin diseases with improved transdermal absorption. Brief description of the drawings [ Fig. 1] The graph shows the decomposition-inhibiting (stabilizing) effect of rapamycin. A noticeable decomposition-inhibiting effect is only observed when the pH is approximately 5.5 to 6.1. [ Fig. 2] The graph shows the ethanol concentration in the composition and the transdermal absorption of rapamycin. It is observed that the concentration of rapamycin in the dermis is higher and transdermal absorption is improved when the ethanol concentration is in the range of approximately 40-50 wt%. Description of the embodiments

[0019] The invention is described in detail below.

[0020] The method for producing a rapamycin-containing composition for the treatment of skin diseases according to the present invention includes, in one embodiment, the steps of dissolving rapamycin in an ethanol-containing solvent, adding a gelling agent and / or a thickening agent to the resulting rapamycin-containing solution, and adjusting the pH of the resulting rapamycin-containing composition to about 5.5 to about 6.1.

[0021] Examples of gelling agents added to the rapamycin-containing solution include water-soluble, cellulose-derived polymers such as hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose, methylhydroxyethylcellulose, methylcellulose, and carrageenan. Examples of thickening agents include carboxyvinyl polymer and hydroxypropylcellulose. These can be used alone or in combination.

[0022] The pH can be adjusted by adding a conventional pH adjuster, such as basic additives, acidic additives, buffering agents, or inorganic salts. Such pH adjusters include basic additives like sodium hydroxide and sodium bicarbonate; acidic additives like hydrochloric acid, sulfuric acid, phosphoric acid, citric acid, tartaric acid, malic acid, mesylic acid, tosylic acid, and besylic acid; buffers like triethanolamine, tris(hydroxymethyl)aminomethane, 2-morpholinethanesulfonic acid, alkali metal salts, alkaline earth metal salts, and ammonium salts. The inorganic salts include calcium chloride, sodium chloride, calcium oxide, and magnesium sulfate.

[0023] The pH adjusting agents include, but are not limited to, various substances, such as those mentioned previously. For example, if the composition contains gelling or thickening agents with a carboxylic acid, preferred pH adjusting agents include at least one selected from the group consisting of sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium bicarbonate, triethanolamine, tris(hydroxymethyl)aminomethane, and 2-morpholinoethanesulfonic acid.

[0024] The method for producing a rapamycin-containing composition for the treatment of skin diseases according to the present invention includes, in one embodiment, the step of mixing rapamycin and ethanol in an amount that results in a concentration of 40-50% by weight in the composition. Specific examples include the following.

[0025] First, rapamycin is dissolved by mixing it with ethanol in an amount that will result in a concentration of 40-50% by weight in the final composition, and a solvent, such as purified water, is added. Then, a gelling agent or thickener, such as a carboxyvinyl polymer, is added, along with any necessary excipients and additives. The mixture is stirred to ensure sufficient swelling of the gelling agent / thickener and homogenization of the mixture. The pH is then adjusted by adding the previously mentioned pH adjuster. The rapamycin-containing composition can be obtained as a gel formulation by adding the aforementioned pH adjuster and adjusting the pH.

[0026] The process for preparing the rapamycin-containing composition for the treatment of skin diseases according to the present invention includes the step of adjusting the pH of the composition in a range of about 5.5 to about 6.1. The pH adjustments and substances used to adjust the pH are described above.

[0027] Furthermore, the method for stabilizing a rapamycin-containing composition for the treatment of skin diseases according to the present invention may include the steps of dissolving rapamycin in an ethanol-containing solvent and adding a gelling agent and / or thickening agent to the resulting rapamycin-containing solution. The gelling agent and the thickening agent to be added to the rapamycin-containing solution are described beforehand.

[0028] The method for inhibiting the decomposition of the rapamycin-containing composition for the treatment of skin diseases according to the present invention includes the step of adjusting the pH of the composition in the range of about 5.5 to about 6.1. The pH adjustments and substances for adjusting the pH are described beforehand.

[0029] The method for inhibiting the decomposition of rapamycin in the rapamycin-containing composition for the treatment of skin diseases according to the present invention may further include the steps of dissolving rapamycin in an ethanol-containing solvent and adding a gelling and / or thickening agent to the resulting rapamycin-containing solution. The gelling and thickening agents to be added to the rapamycin solution are as previously described.

[0030] A rapamycin-containing composition for the treatment of skin diseases (hereinafter referred to as "the rapamycin-containing composition") of the present invention comprises (i) rapamycin, (ii) carboxylic acid-containing aqueous polymer and (iii) at least one pH adjusting agent selected from the group consisting of sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium bicarbonate, triethanolamine, trihydroxymethylaminomethane, and 2-morpholinoethanesulfonic acid, wherein the pH is in a range of about 5.5 to about 6.1.

[0031] The aqueous polymers containing carboxylic acids can be at least one selected from the group consisting of carboxyvinyl polymer, carboxymethylcellulose and carboxyethylcellulose, alone or in combination.

[0032] The method for improving the transdermal absorption of a rapamycin-containing composition for the treatment of skin diseases is characterized by an ethanol concentration of approximately 40 to 50% in the composition. As described in the following examples with reference to experimental data, the inventors have demonstrated for the first time that the transdermal absorption of rapamycin is improved when the ethanol concentration in the composition is approximately 40 to 50%. Improved transdermal absorption in topical compositions for the treatment of skin diseases indicates that the active ingredients can reach the affected area more efficiently.

[0033] Consequently, the present invention can improve the therapeutic efficacy of a rapamycin-containing composition for the treatment of skin diseases.

[0034] The content of rapamycin in the rapamycin-containing composition of the present invention is not particularly limited but can, for example, be from 0.05 to 3 wt% of the total composition, preferably from 0.1 to 2 wt%, more preferably from 0.1 to 0.5 wt%.

[0035] The concentration of the pH-adjusting agent in the rapamycin-containing composition of the present invention is not particularly limited, as long as the pH of the composition can be adjusted to approximately 5.5 to approximately 6.1. Furthermore, the concentration of such a pH-adjusting agent can be selected according to the type of pH-adjusting agent used.

[0036] The rapamycin-containing composition of the present invention may include at least one selected from the group consisting of excipients, additives, and solvents normally used for the preparation of pharmaceutical dosage forms, to an extent that does not interfere with the effects of the invention. Such agents and solvents that may be used are, for example, gelling agents, thickeners, inorganic salts, ethanol, and water. The aforementioned gelling agents, thickeners, and inorganic salts may be used.

[0037] Furthermore, other active ingredients can be added to the rapamycin-containing composition of the present invention, provided they do not interfere with the action of rapamycin, which is the main active ingredient. Such other active ingredients may include, for example, tacrolimus and steroids.

[0038] The rapamycin-containing composition of the present invention can be prepared in optimal dosage forms, such as, for example, cream, paste, jelly, gel, emulsion, and liquid. For example, when used as ointments, liniments, lotions, etc.In addition to the other previously mentioned excipients or additives, at least one of the following may be selected and added as required: sodium alginate; polymers such as gelatin, corn starch, tragacanth gum, methylcellulose, hydroxyethylcellulose, carboxymethylcellulose, xanthan gum, dextrin, carboxymethyl starch, polyvinyl alcohol, sodium polyacrylate, methoxyethylene polymers such as malic anhydride copolymer, polyvinyl ether, and polyvinylpyrrolidone; oils such as beeswax, olive oil, cocoa oil, sesame oil, soybean oil, chamomile oil, peanut oil, beef oil, pig oil, and lanolin; petrolatums such as white petrolatum and yellow petrolatum; paraffin, mixture of liquid paraffin and polyethylene (gelling hydrocarbons); stearic acid; lauryl esters, myristate esters, octanoate esters; cetyl alcohol, steryl alcohol; polyethylene glycol; dimethyl sulfoxide, dodecylpyrrolidone; urea; Eizon; Kaolin, bentonite, zinc oxides, titanium oxide.

[0039] The rapamycin-containing composition of the present invention can, for example, be produced by the following procedure.

[0040] First, dissolve rapamycin in ethanol and add a solvent, such as purified water. Then, add a gelling agent or thickener, such as carboxyvinyl polymer, and, if necessary, add excipients and additives. Stir and mix to ensure sufficient swelling of the gelling agent or thickener and homogenization of the mixture. The pH of the system is then adjusted to approximately 5.5 to 6.1 by adding a pH adjuster.

[0041] The rapamycin-containing composition of the present invention has immunosuppressive properties and can thus be used, for example, to treat skin diseases associated with the immune system.

[0042] Examples of specific skin diseases include dermatitis, contact dermatitis, psoriasis, atopic dermatitis, seborrheic dermatitis, nummular eczema, vitiligo, keloids, autosensitized dermatitis, stasis dermatitis, sebum deficiency eczema, skin tumors of tuberous sclerosis, and skin tumors of Recklinghaus's disease.

[0043] The dosage of the pharmaceutical products and their use of the rapamycin-containing composition of the present inventions can be modified according to the patient's sex, age, physiological condition, pathological condition, and other factors. For example, when used topically, the dosage can range from 0.01 to 100 mg / m². 2 (Body surface area) of rapamycin per adult per day by topical application. Examples

[0044] Although the invention is described below with specific embodiments, it is to be understood that the invention is not limited to these embodiments and that various changes and modifications can be made by those skilled in the art without deviating from the scope or intent of the invention as set out in the accompanying claims. Example 1

[0045] Gel formulations were prepared by mixing each of the ingredients listed in Table 1 at the levels listed in Table 1, and the pH was measured. All formulation samples were clear and colorless gels. Table 1: Composition and content of each formula (weight %) Ingredients formula 1 Formula 2 Formula 3 Formula 4 Formula 5 Formula 6 Formula 7 Formula 8 Formula 9 Formula 10 Rapamycin 0,2 0,2 0,2 0,2 0,2 0,2 0,2 0,2 0,2 0,2 Carboxyvinylpolymer 1 1 1 1 1 1 1 1 1 1 Ethanol 49,42 49,62 49,71 49,76 49,5 49,64 49,72 49,77 48,8 48,3 Triethanolamine 0,38 0,18 0,09 0,04 - - - - 1 1,5 Tris(hydroxymethyl)aminomethane - - - - 0,3 0,16 0,08 0,035 - - Water 49 49 49 49 49 49 49 49 49 49 In total 100 100 100 100 100 100 100 100 100 100 pH during preparation 6,02 5,62 5,09 4,61 6 5,61 5,17 4,71 6,94 7,47

[0046] Approximately 50 g of the gel formulation sample prepared according to each formula were filled into 50 mL glass vials and encapsulated with a PP cap. Each vial was stored in the dark at 50°C for 7 days. Rapamycin was quantified by HPLC at the beginning of the study and after storage under the following conditions. HPLC conditions: Detector: UV absorption spectrophotometer (measurement wavelength: 278 nm) Column: stainless steel tube with an inner diameter of 4.6 mm and a length of 25 cm packed with 5 µm octadecylsilylated silica gel for HPLC Column temperature: constant temperature around 40°C Mobile phase: Acetonitrile / water mixture (13:7) Flow rate: 0.8 mL / min

[0047] Based on the quantification results, the amount of rapamycin decreased was calculated with the start time of the test set to 100, and the stability of each formula was evaluated.

[0048] The results will be presented in Fig. Figure 1 shows that both excessively high and excessively low pH reduced the stability of rapamycin, with rapamycin decomposition being most inhibited at pH levels of approximately 5.5 to 6.1 or approximately 5.6 to 6.0. No difference in the effect on stability was observed between the two pH adjusters (triethanolamine and tris(hydroxymethyl)aminomethane). These results indicate that the inhibitory effect on rapamycin decomposition is primarily due to pH adjustments of approximately 5.5 to 6.1 or approximately 5.6 to 6.0.

[0049] These results confirm that a pH range of approximately 5.5 to approximately 6.1 or approximately 5.6 to approximately 6.0 can suppress the reduction of rapamycin during storage and improves the stability of rapamycin in the rapamycin-containing composition (gel formulation). Example 2(1) Sample preparation

[0050] Gel formulations were prepared by mixing each of the ingredients listed in Table 2 at the levels listed in Table 2. Table 2 Composition and content of each formula (weight %) Ingredients formula 1 Formula 2 Formula 3 Formula 4 Formula 5 Formula 6 Formula 7 Formula 8 Formula 9 Rapamycin 0,1 0,2 0,1 0,2 0,2 0,2 0,2 0,2 0,2 Carboxyvinylpolymer 1,0 1,0 1,0 1,0 1,0 1,0 1,0 1,0 1,0 Ethanol 20,00 20,00 30,00 30,00 30,00 30,00 40,00 49,42 49,42 Triethanolamine 0,38 0,38 0,38 0,38 0,38 0,38 0,38 0,38 0,38 1,3-Butylene glycol 5,0 5,0 5,0 5,0 5,0 5,0 5,0 Water 73,52 73,42 63,52 68,42 63,42 63,42 53,42 44,00 49,00 (2) Transdermal absorption study using cultured human skin cells

[0051] A commercially available model of human skin reconstruction (product name: TESTSKIN LSE-high, manufactured by Toyobo Co.) was used.

[0052] The transfer well with attached cultured tissue was removed from the transport medium, and the attached test ring (10 mm inner diameter) was placed on a uniformly thick area at the tip of the cultured tissue. Approximately 100 mg of the test substance was evenly distributed onto the surface of the cultured tissue within the test ring and incubated for 24 hours in an incubator set to 37°C and 5% CO2. After incubation, the test substance was carefully removed from the surface to avoid damaging the cells. The cells were then sectioned into 8 mm diameter circles, and the epidermal and support layers (polycarbonate layer for attaching the cultured tissue) were removed to obtain a dermal layer sample. 1 mL of methanol was added to the collected dermal layer sample and stirred vigorously to extract the osmotic component.The extract was subjected to LC / MS / MS under the following conditions to quantify rapamycin in the dermal layer. The quantitative value of rapamycin was used to evaluate the transdermal absorption of rapamycin in this sample. HPLC conditions: Detector: UV absorption spectrophotometer (measurement wavelength: 278 nm) Column: Stainless steel tube with an inner diameter of 4.6 mm and a length of 150 mm packed with 5 µm octadecylsilylated silica gel for HPLC. Column temperature: constant temperature around 50°C. Mobile phase: 5 mmol / L ammonium formate containing 0.1 vol% formic acid and acetonitrile mixed in a ratio of 10:90. Flow rate: 0.8 mL / min MS / MS conditions: Ionization mode: ESI positive process Scanning type: MRM Monitored ion: Rapamycin

[0053] The relationship between the ethanol content in each sample and the concentration of rapamycin in the dermal layer is described in Fig. Figure 2 shows that the concentration of rapamycin in the dermal layer increased dramatically at an ethanol concentration of approximately 40%. In other words, at least 40-50% ethanol in the composition improves the transdermal absorption of rapamycin.

[0054] The previously mentioned results indicate that an ethanol concentration of 40-50% in rapamycin-containing compositions improves the transdermal absorption of rapamycin and provides compositions that can be used as preparations for the treatment of skin diseases. Commercial applicability

[0055] The present invention can provide a rapamycin-containing composition for the treatment of skin diseases with reduced degradation of rapamycin and improved stability, thereby making it possible to provide a more effective agent for the treatment of skin diseases.

[0056] The present invention can also provide a rapamycin-containing composition for the treatment of skin diseases with improved transdermal absorption, thereby making it possible to provide a more effective agent for the treatment of skin diseases. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 3805625

[0005] Cited non-patent literature

[0000] R. Balestri et al., Journal of the European Academy of Dermatology and Venereology, 2015, vol. 29, pp. 14-20

[0003]

Claims

[1] A process for preparing a rapamycin-containing composition for treating skin diseases, comprising the steps of dissolving rapamycin in an ethanol-containing solvent, adding a gelling and / or thickening agent to the resulting rapamycin-containing solution, and adjusting the pH of the resulting rapamycin-containing solution to 5.5 to 6.1 with triethanolamine or tris(hydroxymethyl)aminomethane. [2] A method for inhibiting the decomposition of rapamycin in the rapamycin-containing composition for treating skin diseases, the method comprising the step of adjusting the pH of the resulting rapamycin-containing composition to 5.5 to 6.1 with triethanolamine or tris(hydroxymethyl)aminomethane. [3] The method of claim 2, further comprising the steps of dissolving rapamycin in an ethanol-containing solvent and adding a gelling and / or thickening agent to the resulting rapamycin-containing solution. [4] Rapamycin-containing composition for the treatment of skin diseases having a pH of 5.5 to 6.1, comprising (i) rapamycin, (ii) carboxylic acid-containing aqueous polymer and (iii) at least one pH adjusting agent selected from triethanolamine or tris(hydroxymethyl)aminomethane.

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