BR102017011377A2 - anesthetic topical composition and formulation and its use - Google Patents

Abstract

The present invention relates to a topical anesthetic-acting composition and formulation in transdermal film form comprising a pharmaceutically acceptable polymer or carriers and a spilanthol analogue as active ingredient. The results of the local anesthetic effect of the composition and formulation with the active ingredient demonstrate a high effectiveness of action over a long duration compared to other formulations.

Description

ANESTHETIC TOPIC COMPOSITION AND FORMULATION AND ITS USE Campo da. invention:

[1] The present invention falls within the field of application of medical science, more specifically in the pharmaceutical area, since it refers to a topical anesthetic composition and formulation in the form of film comprising a polymer and the compound (2E, 8E) - N-isobutyldeca-2, 8-dien-6-inamide, as an active ingredient.

Basics of the invention:

[2] Spilantol is an N-alkylamide present in Spilanthes acmella, responsible for several biological activities, especially antinociceptive activity. The first synthetic route for obtaining it was described in 1963, and most of the syntheses described presented low overall yields or a large number of stages, in addition to not describing the purity of the compound.

[3] Recently, the patent document BR 10 2016 017871 1 revealed a process for obtaining spilantol and analogues through a shorter, cheaper and more efficient route, leading to a final product of greater purity when compared to the routes present in the literature.

[4] One of the analogs of the obtained spilantol, (2E, 8E) -Nisobutyldeca-2,8-dien-6-inamide, showed an anesthetic potential superior to that of spilantol and the positive control (EMLA®) in the preliminary tests performed. Its structure is similar to that of spilantol, differing only by the triple bond instead of the double bond with Z geometry, generating greater rigidity in that portion of the molecule. Its synthesis has one less stage and an overall yield of 34%.

[5] The surgical and cosmiatric procedures performed by dermatologists, such as laser for hair removal, tattoo removal and rejuvenation, curettage, electrocoagulation, cryotherapy, injectable fillers, application of botulinum toxin, sclerotherapy, chemical peels, among others, often require use of

2/14 local anesthetics for patient comfort. Traditionally, the anesthetic agent of choice is injectable lidocaine. Although it is very effective in producing total local anesthesia, the injection causes pain and systemic action.

[6] In this sense, the use of topical anesthetics would lessen the discomfort caused by injectable versions. Currently, there are several topical anesthetics available that can relieve the discomfort caused by these procedures, without the need for injections. However, topical anesthetics in the state of the art present a number of technical problems, such as problems with proper diffusion and distribution through the skin.

[7] The ideal topical anesthetic agent is one that promotes total anesthesia quickly, acts on intact skin without causing systemic adverse effects and does not cause pain or discomfort.

[8] GB2008946 describes a cream emulsion that enhances the effect of the local anesthetic using a low concentration of a commercially known anesthetic.

[9] CN106138530 also describes an anesthetic cream that comprises active ingredients commercially used for surgery applications. The document reveals a combination of two or more active ingredients, or even a combination of medicinal plants to obtain the desired anesthetic effect.

[10] EMLA® is also a cream indicated for topical anesthesia of the genital mucosa for superficial surgery or before infiltrative anesthesia. The product is contraindicated in patients with hypersensitivity to lidocaine, prilocaine, to other components of the formula or to local anesthetics of the amide type, and to patients with congenital or idiopathic methaemoglobinaemia. In addition, due to insufficient absorption data, EMLA® should not be applied to open wounds other than leg ulcers, to the genital mucosa of children or to a ruptured tympanic membrane.

3/14 [11] The cream dosage form may cast doubt on the amount needed to be applied to obtain the desired anesthetic effect. As described in the technologies, the cream enhances the action of the local anesthetic, but if applied in the wrong amount, it may not guarantee that the desired effect is achieved.

[12] Thus, the development of a topical anesthetic formulation capable of allowing the correct dosage of the drug, with an improvement in its diffusion through the hair, in addition to the advantage of being able to be applied on wounds and burns, are advantageous characteristics in relation to state of the art. The present invention proposes a topical anesthetic composition and formulation in the form of a transdermal film. Said composition comprises a polymer and a new compound analogous to spilantol, (2E, 8E) N-isobutyldeca-2,8-dien-6-inamide. The anesthetic capacity of the film proposed here was evaluated in vivo, showing greater effectiveness and duration of anesthesia when compared to the positive standard used commercially (EMLA®).

[13] Therefore, the proposed invention uses in its composition and formulation only a new active, (2E, 8E) -Nisobutildeca-2,8-dien-6-inamide, which obtained the best result when compared to the most used local anesthetic clinically. Still, the formulation is arranged for the patient to apply the exact dose, and in addition to being applied to the skin, the formulation can be applied to wounds or burns, since polymers, such as hydroxyethylcellulose, are already known to be used in dressings.

[14] Therefore, prior art documents do not contemplate a topical anesthetic composition or formulation in the form of film comprising (2E, 8E) -N-isobutyldeca-2,8dien-6-inamide, as proposed by the present invention.

[15] Most anesthetic compositions are used in an injectable form, causing pain and discomfort

4/14 to patients. The development of topical compositions is essential to improve patient compliance and decrease discomfort. The cream pharmaceutical form can cause doubts in the amount needed to be applied to obtain the desired anesthetic effect. The cream enhances the action of the local anesthetic, but if applied in the wrong amount, it may not guarantee that the desired effect is achieved.

[16] Thus, the development of a topical anesthetic composition capable of allowing the correct dosage of the drug, with an improvement in its diffusion through the skin, without causing discomfort to patients, in addition to the advantage of being able to be applied on wounds and burns, constitute advantageous features in relation to the state of the art. The present invention proposes a topical anesthetic composition in the form of a transdermal film.

[17]

Brief description of the invention:

[18] The present invention relates to a topical anesthetic composition in the form of a transdermal film comprising a polymer, pharmaceutically acceptable excipients and (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide, as an active ingredient. Said formulation comprises (2E, 8E) -N-isobutyldeca-2,8-dien-6-dynamamide, hydroxyethylcellulose (HEC), glycerin, Tween 80® and Transcutol®. The anesthetic action of the formulation was evaluated through in vivo testing, in comparison to the commercially available topical anesthetic, EMLA®, and spilantol formulations, showing greater effectiveness and duration of anesthesia when compared with the positive standard used commercially (EMLA®) .

Brief description of the figures:

[19] Figure 1 represents the images of the aspect of the topical anesthetic formulation in film form at each stage of the production process, it was that (A) represents the end of step b, (B) represents the end of step e, and , (C) and (D)

5/14 the end of steps e and f.

[20] Figure 2 is a photograph of an example of the film cut to 17 mm in diameter.

[21] Figure 3 graphically represents% EMP (maximum possible effect) x Time (min) of spilantol, (2E, 8E) -Nisobutyldeca-2,8-dien-6-inamide and EMLA®.

[22] Figure 4 graphically represents the duration of anesthesia (min) in the treatment with each formulation.

[23] Figure 5 is a graph of the permeation profile of the composition with spilantol and the compound (2E, 8E) -Nisobutyldeca-2,8-dien-6-inamide through the skin of a dermatologist's pig ear , obtained in the Franz cell permeation experiment.

Detailed description of the invention:

[24] The present invention relates to a topical anesthetic composition and formulation. In particular, the described composition comprises a polymer, pharmaceutically acceptable excipients and (2E, 8E) -N-isobutyldeca-2,8dien-6-inamide as an anesthetic active ingredient.

[25] The term pharmaceutically acceptable excipient refers to a compound which, in a given pharmaceutical formulation, is compatible with other ingredients present and suitable for use in contact with the tissue or organ of humans and animals without toxicity, irritation, allergy, allergic response, excessive immunogenicity or other problems or complications, compatible with a reasonable benefit / risk ratio. (Rowe et al., Handbook of Pharmaceutical Excipients. 5 ^to Ed, Pharmaceutical Press, 2005).

[26] The new composition described here comprises a polymer and a compound, analogous to spilantol, (2E, 8E) -Wisobutyldeca-2,8-dien-6-inamide. The anesthetic capacity of the film proposed here was evaluated in vivo, showing greater effectiveness and duration of anesthesia when compared to the positive standard used commercially (EMLA®).

6/14 [27] The proposed transdermal topical anesthetic composition comprises an anesthetic agent, and pharmaceutically acceptable excipients.

[28] The present invention comprises excipients: polymers, humectants, surfactants and solvents.

[29] Polymers include cellulose derivatives, chitosan, starch, polyvinyl alcohol and polyvinylpyrrolidone. Preferably the polymer used is hydroxyethylcellulose (HEC).

[30] Examples of humectants include propylene glycol, sodium diacetyl sulfosuccinate, sodium lactate, sorbitan and glycerin. Preferably, the humectant used is glycerin.

[31] Examples of surfactant agents include fatty esters derived from sorbitol, such as polysorbate 20, 40, 60 and 80, derived from carboxylic acids, sulfates, derived from phosphoric acids and quaternary ammonium salts. Preferably, the surfactant used is polysorbate 80 (Transcutol®).

[32] Preferably, the amount of (2E, 8E) -Nisobutyldeca-2,8-dien-6-inamide per dosage form is at least 0.35%. More preferably, the amount of (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide is 0.35%.

[33] Preferably, the amount of hydroxyethylcellulose (HEC) per dosage form is between 2 and 15% and more preferably the amount is 2.5% per dosage form.

[34] Preferably, the amount of glycerin per dosage form is between 0.5 and 5% and more preferably the amount is 0.7% per dosage form.

[35] Preferably, the amount of polysorbate 80 per dosage form is between 0.5 and 5% and more preferably the amount is 0.7% per dosage form.

[36] Preferably, the amount of 2- (2-ethoxyethoxy) ethanol (Transcutol®) per dosage form is between 1 and 25%

7/14 and more preferably the amount is 2.5% per dosage form.

[37] A preferred example of the composition of the present invention is described below.

[38] The topical anesthetic formulation comprises:

- at least 0.35% (dry film) of (2E, 8E) -Nisobutyldeca-2,8-dien-6-inamide, preferably 0.35%;

- from 2 to 15% polymer, preferably hydroxyethylcellulose (HEC), preferably 2.5%;

- 0.5 to 5% glycerin, preferably 0.7%;

- 0.5 to 5% of polysorbate 80, preferably 0.7%;

- 1 to 25% of 2- (2-ethoxyethoxy) ethanol, preferably 2.5%; and

- QSP 100% hydroxyethyl cellulose gel, wherein said gel comprises from 2 to 15% hydroxyethyl cellulose, preferably 2.5%.

[39] In which the polymer is selected from the group consisting of cellulose derivatives, chitosan, starch, polyvinyl alcohol and polyvinylpyrrolidone, preferably hydroxyethylcellulose (HEC).

[40] To obtain the aforementioned composition, the spilantol analogue (2E, 8E) -N-isobutyldeca2,8-dien-6-inamide (1), with chemical formula C14H21NO, molecular weight 219,32 and chemical structure (1).

[41] For the synthesis of said (2E, 8E) -N-isobutyldeca-2,8dien-6-inamide (1), two different oxidation reactions (ie ii) and three variants (iii, iv and v) of the HornerWadsworth-Emmons (HWE) can be employed, totaling 4

8/14 different routes described in Table 2.

Table 2. Synthesis routes for (2E, 8E) -N-isobutyldeca-2,8dien-6-inamide (1).

Input Oxidation HWE Yield for isomer 2E, 8E (%) ^a 1 PCC, NaOAc (i) NaH, diethyl (2- (isobutylamino) -2oxoethyl) phosphonate (iii) 43 2 Swern (ü) NaH, diethyl (2- (isobutylamino) -2oxoethyl) phosphonate (iii) 43 3 Swern (ii) LiCl, DBU, (2- (isobutylamino) -2oxoethyl) diethyl phosphonate (iv) 31 4 Swern (ii) Et ;, N, Zn (OTf)., TMEDA, (2- (isobutylamino) -2oxoethyl) diethyl phosphonate (v) 46

^a Isolated yield for both stages.

[42] For better visualization, the following is the synthesis of (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide (1).

[43] To achieve the preferred modality, the active ingredient was obtained by the process described in patent application BR 10 2016 017871 1 entitled Process for obtaining spilantol and analogs, spilantol and analogs obtained.

9/14

Process of preparing the core [44] Biofilm is considered essential to achieve the different characteristics presented by the formulations described here.

[45] The process steps for obtaining the biofilm are:

The. Prepare a polymer solution, preferably hydroxyethylcellulose (HEC);

B. Rest the solution until it reaches a temperature of 25 ° C;

ç. Add the adjuvants for solubilization;

d. Solubilize (2E, 8E) -N-isobutyldeca-2,8-dien-6inamide in alcohol;

and. Add the solubilized (2E, 8E) -N-isobutyldeca-2,8-dien-6inamide to the obtained gel; and

f. Get the movies.

[46] In step a , are produced the movies in hydroxyethylcellulose by method casting, The from an solution watery hydroxyethylcellulose in a track in agitation constant between 300 and 7 00 rpm (The agitation more

vigorous formation of unwanted bubbles) and heating at a temperature ranging from 53 to 57 ° C, preferably 55 ° C, until the solution forms a translucent gel.

[47] HEC is a water-soluble, low-toxic, film-forming polymer derived from cellulose, therefore renewable. Polymers are of special interest because, as a rule, they have low toxicity, high absorption and swelling capacity, in addition, several active compounds can be incorporated into these polymers.

[48] In step b, the mixture obtained is put to rest until it reaches 25 ° C. Then, in step c the assets are slowly incorporated, to ensure that a homogeneous mixture is obtained.

[49] In step d, from 18.7 μτηοΐ to 54 pmol, preferably 18.7 pmol of (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide are solubilized in an organic solvent, preferably

10/14 methanol or ethanol (maximum volume of 1 mL). In the step and each solution was added in a portion of gel and homogenized.

[50] Soon afterwards, in step f, the gel obtained is left to rest until the end of the bubbles, deposited on Nylon plates and dried in an oven for 20 to 30 hours at a temperature of 35 to 45 ° C, preferably for 24 hours. at 40 ° C.

[51] Figure 1 shows the images of the formulation aspect at each step, where (A) represents at the end of step b, (B) represents at the end of step e, and, (C) and (D) at the end of steps e and f.

Example 1: Determination of the physical properties of films:

[52] A solution of hydroxyethylcellulose (2.5 g) in 100 ml of distilled water was prepared under heating (55 ° C ± 2 ° C) and constant stirring until the solution formed a translucent gel. The mixture was left to stand until it reached room temperature. Then, the adjuvants polysorbate 80 (Tween 80®) (0.7 g), glycerin (0.7 g) and 2- (2-ethoxyethoxy) ethanol (Transcutol®) (2.5 g) were added. The gel was separated into 30 g portions.

[53] 4.12 mg (18.79) of (2E, 8E) -Nisobutyldeca-2,8-dien-6-inamide was solubilized in methanol (maximum volume 0.5 ml). The obtained solution was added in a portion of gel and homogenized. Then, the obtained gel was left to rest until the end of the bubbles, deposited on Nylon plates and dried in an oven for 24 h at 40 ° C.

[54] After drying, the films were removed from the plates and cut with a hole punch with a diameter compatible with the proposed tests. The films were weighed on an analytical balance and their thickness was measured with a macrometer at three different points, the mean and standard deviation of the measurements were calculated.

[55] After cutting the films with the punch, they showed similar physical aspects: homogeneous, intact and slightly opaque as illustrated in Figure 2.

[56] The thickness (mm) and mass (g) measurements of the films

11/14 range from 0.3649 to 0.3643 mm, and 105.2 to 87.2 mg, preferably 0.3664 mm and 96.2 mg, respectively.

Example 2: Determination of antinociceptive activity of the composition by the Tail Flick Assay, in vivo:

[57] The trial was conducted on mice that were separated into groups containing six mice each. In each group, a film with an active ingredient was used, a positive control group, in which EMLA® 150 mg / animal was used (eutectic mixture of 2.5% prilocaine and 2.5% lidocaine) and a negative control group in which only the film is applied, with no active ingredient.

[58] Male Swiss mice were contained in an acrylic cylinder keeping the distal portion of the tail (10 cm) free and in contact with a spotlight at 55 ° C. The time required for tail removal (latency) was considered an aversive response to heat. The baseline value of each animal was noted before the beginning of the experiment and only those that reached a baseline value of up to 6 seconds were considered for the experiment. To avoid thermal injury, a maximum time of 10 seconds for contact with the heat source (cut-off) was established.

[59] After measuring the baseline time, the film was applied at 2 cm from the base of the animal's tail for 5 min. Then it was removed and the first measurement was taken, exposing the tail to the spotlight in the same region where the film was applied. The other measurements were made every 15 min until each animal reached its baseline stimulus value. Analgesia was defined as an increase in the time required for tail removal, at least 50% greater than the observed baseline value.

[60] Figure 3 shows a graph of the maximum effect possible over time. The maximum possible effect (EMP) is calculated as (L - B) 10 - B x 100 where L = latency (value obtained in the test), B = baseline value of the animal and 10 refers to the cut-off value of the test.

[61] Anesthesia duration was calculated as the mean of the

12/14 time that each animal took to return to its baseline value. Figure 4 has a graph of the average duration in minutes of treatment with each compound.

[62] As expected, there was no antinociceptive effect in animals treated with hydroxyethylcellulose bioadhesives with no active ingredient (negative control - data not shown in the graphs).

[63] From the graphs contained in Figures 3 and 4 it was possible to conclude that spilantol presented a better response to the test when compared to EMLA®. The duration of anesthesia of spilantol is 70 ± 18 min while for EMLA® this value is 58 ± 35 min. However, compound (1) stood out, showing results superior to the positive control (EMLA®) and also to spilantol.

[64] In addition to a long duration (146 + 62 min), the compound (1) was also very potent, with high EMP values. Its structure is similar to that of spilantol, the only difference being the triple bond instead of the double bond with Z geometry, which generates greater rigidity in that portion of the molecule. Its synthesis has one less stage and an overall yield of 34%.

[65] It is interesting to note that this antinociceptive effect was obtained with only five minutes of application of the bioadhesive on the animal's tail, showing the speed of the intended action in the methodology employed.

[66] All results were submitted to single-way analysis of variance (ANOVA) and Tukey, considering as a critical level p <0.05 to be considered a significant difference between the control and treated groups, the analyzes were made with the GraphPad Prism® statistical package.

[67] The formulation comprising the compound (1), in addition to a long duration (146 ± 62 min), also proved to be very potent, with high EMP values.

Example 3: In vitro permeation test of the composition with spilantol and (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide

13/14 contained in the films through skin of a pig's ear dermatomized in a vertical diffusion cell type Franz [68] The pig ears must be purchased in a slaughterhouse duly certified by the São Paulo State Department of Agriculture and Supply shortly after the sacrifice of the animals and transported in phosphate buffer (pH 7.4). The methodology used was based on works published by Dias et al. (2010) and Cereda et al. (2013). The skin was removed from the external part of the ear, separated from the underlying cartilage with the aid of a scalpel, dermatomized (500 μπι) and frozen at -20 ° C until use.

[69] The permeation experiment through dermatomized pig ear skin was carried out in the Franz-type vertical diffusion cell (Manual Diffusion Test System 1, Hanson Research Corporation, Chatsworth, CA, USA) with a permeation area of 1.77 cm ² and 7 mL of volume. Formulations containing spilantol and (2E, 8E) -N-isobutyldeca2, 8-dien-6-yamide cut in circles with a diameter of 17 mm were used.

[70] The film and skin were fixed between the donor and recipient compartments. A solution containing saline and methanol (70:30, v / v) was used as a receiver liquid, and kept under constant agitation (350 rpm). Samples (400 pL) were periodically removed from the recipient compartment and immediately replaced with the same volume of solution, taking into account the effects of dilution. The samples were transferred to chromatography flasks for quantification of spilantol and (2E, 8E) -N-isobutyldeca-2,8dien-6-inamide by HPLC.

[71] After quantification by HPLC, the permeation parameters of the composition of spilantol and (2E, 8E) -M-isobutyldeca-2,8-dien-6-inamide were calculated, such as: time required for initial permeation or time lag and flow. The experiments were carried out in at least quadruplicates.

[72] For each cell, a graph was constructed from the

14/14 amount of spilantol and (2E, 8E) -N-isobutyldeca-2,8dien-6-inamide accumulated in the receiving compartment as a function of time (time intervals for each collection). The slope of the linear portion of the graphs represents the permeation flow of spilantol and 2E, 8E) -N-isobutyldeca-2,8-dien6-inamide through the skin and its intersection with the abscissa axis allowed the determination of the time latency (time lag). The data were expressed as mean ± standard deviation.

[73] Figure 5 shows the permeation profile of the composition comprising spilantol and (2E, 8E) -N-isobutyldeca-2,8dien-6-inamide from the different evaluated films. The permeation parameters (flow and time lag) are shown in Table 1.

Table 1 - Permeation parameters of the formulation with spilantol and (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide applied in finite dose condition through pig esophageal mucosal epithelium.

Formulation Flow (μς. Cm'-. H ^_1 ) Time lag (H) Spilantol 0.78 + 0.11 0.66 ± 0.41 (2E, 8E) -N-isobutyldeca-2,8- dien-6-inamide 0.88 ± 0.09 0.81 ± 0.43

(mean ± SD; n = 4)

Claims (7)

1. Topical composition characterized by the fact that it comprises: - pharmaceutically acceptable excipients; and - (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide, with chemical formula C14H21NO, molecular weight 219, 32 and chemical structure o 2. Composition according to claim 1, characterized in that the excipients are preferably polymers, humectants, surfactants and solvents. 3. Composition, according to claim 1, characterized by the fact that it is preferably in the pharmaceutical form of transdermal film. Composition according to claim 2, characterized in that it comprises a polymer selected from the group consisting of cellulose and chitosan derivatives, starch, polyvinyl alcohol, polyvinylpyrrolidone and hydroxyethylcellulose (HEC) present in the amounts from 2.0 to 15.0 % and, preferably 2.5% of the dosage form, the polymer being preferably hydroxyethylcellulose (HEC). Composition according to claim 2, characterized in that it comprises a humectant selected from propylene glycol, sodium diacetyl sulfosuccinate, sodium lactate, sorbitan and glycerin present in the amounts of 0.5 to 5.0% and, preferably, 0, 7% of the dosage form, the humectant being preferably glycerin. 6. Composition according to claim 2, characterized in that it comprises a surfactant selected from the group consisting of esters derived from sorbitol present in the amounts of 0.5 to 5.0% and preferably 0.7% of the dosage form , the surfactant being preferably polysorbate 80. 2/3 Ί. Topical formulation characterized by the fact of understanding: - at least 0.35% of (2E, 8E) -N-isobutyldeca-2,8-dien6-inamide; - from 2 to 15% of hydroxyethylcellulose polymer; - from 0.5 to 5% glycerin; - from 0.5 to 5% of polysorbate 80; and - from 1 to 25% of 2- (2-ethoxyethoxy) ethanol. 8. Formulation, according to claim 7, characterized by the fact that it preferably comprises: - 0.35% (2E, 8E) -N-isobutyldeca-2,8-dien-6-inamide; - 2.5% hydroxyethyl cellulose polymer; - 0.7% glycerin; - 0.7% polysorbate 80; and - 2.5% of 2- (2-ethoxyethoxy) ethanol. 9. Formulation according to claim 7 or 8, characterized by the fact that the active ingredient (2E, 8E) -Nisobutyldeca-2,8-dien-6-inamide has chemical formula C14H21NO, molecular weight 219,32 and chemical structure o Formulation according to claim 7 or 8, characterized in that the polymer is selected from the group consisting of cellulose and chitosan derivatives, starch, polyvinyl alcohol and polyvinylpyrrolidone, preferably hydroxyethylcellulose (HEC). 11. Formulation according to claim 7 or 8, characterized by the fact that it is preferably in the pharmaceutical form of transdermal film. 12. Use of the composition as defined in claims ^{1 to} 6, characterized in that it is for antinociceptive application. 13. Use according to claim 12, characterized 3/3 because it has local topical application. 14. Use of the formulation as defined in the claims 7 to 11, characterized by the fact that it is antinociceptive. 15. Use, according to claim 14, characterized by the fact that it has local topical application.