EP1458415A2

EP1458415A2 - Amphiphilic compounds for pharmaceutical or cosmetic use

Info

Publication number: EP1458415A2
Application number: EP02805808A
Authority: EP
Inventors: Nicolas Calvet
Original assignee: Physica Sarl
Current assignee: Physica Sarl
Priority date: 2001-12-27
Filing date: 2002-12-24
Publication date: 2004-09-22
Also published as: WO2003055528A2; CA2472124A1; FR2834215B1; WO2003055528A3; AU2002364684A1; US20050069513A1; FR2834215A1

Abstract

The invention concerns amphiphilic compounds for pharmaceutical or cosmetic use, consisting of an ion pair complex between an acylated amino acid and a biologically active molecule. Said formed compounds enable to enhance the pharmaceutical or cosmetic properties of the molecules in particular of small organic molecules, or peptides and of proteins, or nucleotides or of genes.

Description

Amphiphilic compounds for pharmaceutical or cosmetic use

Technical area

The present invention relates to the formation and pharmaceutical or cosmetic use of an amphiphilic compound called an "amphiphilic ion pair" (or "PIA") resulting from an ionic interaction between an acyl amino acid and an active pharmaceutical or cosmetic molecule.

State of the art

The pharmacological activity of an active principle does not depend solely on its chemical structure and therefore on its physico-chemical properties, but also on its ability to reach its active site, that is to say the place where it acts and this in sufficient quantity. This property is called "bioavailability".

The bioavailability of an active ingredient strongly depends on the route used to administer it (enteral and parenteral route). In fact, depending on the route of administration, the active principle may encounter obstacles reducing its absorption; it can dissolve more or less in biological fluids, undergo more or less bio-transformations and ultimately be more or less absorbed. It is therefore important to choose the best route of administration for a given active ingredient.

The most widely used route of administration is the oral route. This choice is clearly explained by the ease of swallowing a drug and by the fact that the digestive tract represents an interesting absorption site.

However, the preferential use of the oral route as a route of administration leads to the exclusion of a good number of pharmacologically promising active molecules, for problems of bio-transformation or absorption defects. Indeed, this would lead to use high doses of active ingredients responsible for a high cost of treatment and / or increased toxicity incompatible with the marketing of the product. The clinician may then have recourse to an alternative administration such as the injectable route (SC, IM, IV).

Those skilled in the art have therefore sought technical means for improving the protection of the active molecule, that is to say increasing the quantity of compounds capable of arriving at the absorption site. He also sought to modify the resorption of the active molecules by acting either on its solubility in the case where the dissolution is the factor slowing the absorption of the molecule, or by improving the intestinal transmembrane passage.

With regard to the improvement of absorption by the reduction of bio-transformation phenomena, the person skilled in the art has developed mainly liquid preparations such as water in oil emulsions, that is to say systems where the hydrophilic phase is dispersed in the lipophilic phase, or multiple emulsions of the Water in Oil in Water type.

American patent US-A-5, 897, 876 presents emulsified systems of the H / L type, that is to say made up of a hydrophilic phase dispersed in a lipophilic phase. These systems create a lipophilic environment around the active molecule, thereby increasing the amount of molecules absorbed. Indeed, they allow protection of the active ingredients against the destabilizing action of proteolytic enzymes and gastrointestinal fluids. This protection would thus increase the amount of active ingredient arriving at its absorption site.

However, the reduced proportion of the dispersed phase

(less than 10%) of these systems limits the amount of active ingredient capable of being dissolved. In addition, the presence of ethanol in the hydrophilic part can lead to destabilization of the system and cause irritant effects at the cellular level. A more recent approach consists in improving the absorption by increasing the lipophilic nature of the active molecules by the formation of ionic complexes. US-A-5,853,740 highlights the advantage of systems using sodium dodecylsufonate as complexing agent. These means are used to improve the absorption of weakly absorbed active molecules (ie molecules weakly absorbed at the level of the intestinal membrane). These complexes consist of a pair of ions between active molecules of acidic or basic nature and an amphiphilic compound with basic or acidic free ionic function. The complex resulting from this association is present either in the form of a precipitate in the hydrophilic phase (patent WO 0132218) or in the form dissolved in an organic solvent (patents US-A-5, 770, 559 and US-A- 5,853,740) of ethanol, octanol, DMSO, DMF, or N methyl pyrrolidone type.

One of the advantages of these complexes is that they allow the conservation of the three-dimensional structure of the active substance. Certain molecules can indeed lose their biological activity in the event of denaturation of this structure. These various patents indicate that the use of such complexes can improve the bioavailability of the active ingredients.

The authors of patent US-A-5,770,559 use a method for preparing a homogeneous organic solution of an active compound in which said active compound is not normally soluble. This solubilization is obtained by forming a hydrophobic ion pair complex between an amphiphilic compound and said active molecule. The complex thus obtained can be transformed into solid particles by precipitation in a supercritical fluid, for administrations by inhalation, in particular by using the nasal mucosa.

Like the previous patent, patent WO 0132218 seeks to improve the bioavailability of active principles hydrophilic insoluble in a lipophilic phase, decreasing their solubility in the hydrophilic phase and increasing their solubility in said lipophilic phase. To achieve this, the authors of this patent use amphiphilic counterions by forming with the hydrophilic compound a hydrophobic complex of the ion pair type.

The inventions relating to these patents are directed towards reducing the hydrophilic nature of the active principle. These patents base their approach on the reduction of the solubility in the aqueous phase to increase the solubility in the organic or lipophilic phase. This object is achieved by the formation of a hydrophobic ion pair complex. This formation results from the complexation between an active principle and an amphiphilic compound, in particular sodium lauryl sulfate (SLS), sodium dodecyl sulfate (SDS) or a zwitterion.

The teaching of these patents is therefore limited to the formation of hydrophobic ion pair complexes. These complexes are therefore essentially dissolved in organic solvents. These hydrophobic complexes can therefore hardly be used in the hydrophilic phase or in the dispersed phase of the hydrophilic phase type in the lipophilic phase, in particular water in oil.

It has been known to those skilled in the art since the 1950s, means of obtaining inorganic salts (sodium or potassium in particular) of acyl amino acid. Because of their amphiphilic properties, these compounds have been used since those years in the field of detergents. Acyl amino acids are also used in the field of cosmetics as amino acid biovectors.

More recently, acyl amino acids have been used as absorption promoters. US Patent 5650386, WO 0135998 and WO 0151454 disclose the use of acyl amino acids in pharmaceutical compositions.

The patent US 5650386 describes a technique for encapsulating the active ingredients. During the preparation of the composition, the acyl amino acids will form microspheres constituting hollow matrices inside which the active principle will be enclosed (or encapsulated). The active ingredient will thus be protected from various degradations. Patent WO 0135998 describes acyl amino acids as absorption promoters, dissolved in biphasic lipid vesicles of the liposome type.

WO 0151454 describes an aqueous phase mixture between an acyl amino acid and an active ingredient. In this patent the simple presence of acyl amino acids promotes absorption.

All the systems described above provide only incomplete solutions in the case of ionizable and slightly permeable hydrophilic molecules. In addition, no teaching from the prior art could encourage the use of these acyl amino acids to form ion-pair complexes soluble in the hydrophilic phase.

Disclosure of the invention The object of the present invention is therefore to form complexes between a compound and an active principle, which can be soluble in the hydrophilic phase and therefore usable in aqueous solution directly or in a dispersed system of the H / L type (phase hydrophilic dispersed in a lipophilic phase).

More specifically, the subject of the present invention relates to a compound for pharmaceutical or cosmetic use, consisting of an ion pair complex between an acyl amino acid and a biologically active molecule, used in therapeutic or cosmetic treatments , the complex being amphiphilic.

The interaction between the acyl amino acid and the active pharmaceutical or cosmetic molecule corresponds to the interactions found within complexes, also called coordination compounds. Such an interaction is qualified according to the literature of coordination link, coordination link or even dative link. The compound resulting from this association has amphiphilic properties and is therefore called "amphiphilic ion pair" (or "PIA"), or amphiphilic ion pair complex (or "PIA" complex). The invention generally applies to molecules of an organic and hydrophilic nature, the properties of which do not allow it to easily cross biological membranes and / or which are rapidly bio-transformed in one organism. These amphiphilic compounds have the advantage of improving the availability of the active ingredients in the body and of retaining the 3D structure of these active ingredients. They also have the advantage of being inserted at the interfaces of dispersed systems, thus making it possible to protect said compound from bio-transformations and therefore to prolong the life of the active molecules.

Detailed description of the invention

More specifically, the invention applies to biologically active molecules such as short peptides, polypeptides, proteins, hormones, antigens, nucleotides or genes, the properties of which do not allow them to easily cross the biological membranes and / or which are rapidly bio-transformed in the body. According to the invention, a "PIA" complex is formed between one of these molecules and an acyl amino acid. The absorption of this molecule will thus be improved thanks to the amphiphilic properties of this complex.

The major advantage of these compounds is that the presence of the acyl amino acid gives them an amphiphilic character and not a hydrophobic character. The "PIA" resulting from this association remains in solution and is preferentially localized at the interfaces of dispersed systems. This surprising property distinguishes the complexes formed from an acyl amino acid from the other complexes commonly formed from ions, such as sodium lauryl sulfate (SLS) or sodium dodecyl sulfate (SDS), which have a hydrophobic character.

Thus, these complexes are preferably used for biologically active hydrophilic molecules. In fact, the latter, because of their hydrophilic property, hardly pass through the biological membrane. The amphiphilic nature of the complex thus improves the transmembrane passage of the active principle. In addition, this amphiphilic nature also makes it possible to use this complex in solution in water or in the hydrophilic phase of a dispersed system, which is impossible with a hydrophobic complex. Thus, although the transmembrane passage of the active principle is improved, it is therefore still usable in the hydrophilic phase. It should be noted that by constituting a complex between an acyl amino acid in the native state, that is to say non-salified, and an active principle which is not soluble in water, an amphiphilic complex can also be obtained which can then be dissolved in hydrophilic phase and always easily passing through biological membranes.

The term "acyl amino acid" means any compound resulting from an acylation between a fatty acid of natural, synthetic or modified origin and a natural, synthetic or modified amino acid, the fatty acid comprising from 4 to 40 carbon atoms and the amino acid. having at least one acid function and at least one free amino function. More particularly, one of the amino functions is located in the alpha position relative to the carboxylic acid function.

As amino acid can be used by way of example: aspartic acid, glutamic acid, alanine, arginine, cysteine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, ornithine, taurine, threonine, tryptophan, tyrosine, serine or valine.

As fatty acid can be used by way of example: capric acid, caprylic acid, acid lauric, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, essential fatty acids such as eicosapentaenoic acid (EPA), or docosahexaenoic acid (DHA).

Various acyl amino acids are thus obtained, such as oleyl glycine, capryloyl glycine, oleyl sarcosine, lauroyl proline, oleyl lysine, lauroyl lysine, palmitoyl phenylalanine or capryloyl serine. According to a preferred embodiment, the amphiphilic compound results from the interaction between, at least one of the reactive functions of the active principle and at least one reactive function carried by the acyl amino acid, generally an acid or amino function. The reactive function of the active ingredient generally has a basic or an acidic character. It is an interaction as defined previously in the present application, that is to say of the type that is found within the complexes.

By biologically active molecules, also commonly called active ingredients, is meant molecules having therapeutic or cosmetic properties. These biologically active molecules can be organic molecules, short peptides consisting of 2 to 20 amino acids, nucleotides, genes, polypeptides, proteins, hormones or antigens.

By way of example, mention may be made of amoxicillin, losartan, pravastatin, diclofenac, lidocaine, vancomicin, spiramicin, neomicin, colistin, cimetidine, ranitidine, insulin, vasopressin, calcitonin, angiotensin, secretin, heparin, growth hormone, erythropoietin, parathyroid hormone or filgastrin.

According to an advantageous mode of preparation, said amphiphilic compounds can be inserted into dispersed systems. By dispersed systems is meant systems composed of two immiscible phases, one generally the other hydrophilic lipophilic and one or the other of these two phases constitutes the dispersing phase or the dispersed phase. By miscibility is meant the property for two compounds of being able to mix, one with the other, forming only one continuous phase.

Another object of the invention is therefore a dispersed system comprising a complex according to the present invention.

According to a preferred embodiment, the internal dispersed phase (hydrophilic or lipophilic) and the dispersing phase (lipophilic or hydrophilic) contain one or more emulsifiers and / or viscosants.

According to a particularly advantageous embodiment of the invention, the ion pair complex is obtained by mixing two phases named A and B which are prepared separately. Phase A contains at least one acyl amino acid in the dissolved or dispersed state and forms a miscible or dispersible mixture in phase B. Phase B contains at least one active principle in the dissolved or dispersed state and forms a miscible or dispersible in phase A.

During the incorporation of phase A into phase B, or vice versa, an interaction is formed between the acyl amino acid and the active principle so that there is formation of a "pair of amphiphilic ions". When phase A is miscible in phase B, there is obtained after mixing, a single and single phase comprising the amphiphilic ion pair complex solubilized in this single phase. When phase A is dispersible in phase B, after mixing, a dispersed system is obtained in which the "PIA" complex is present in dissolved form inside the internal phase and preferably is inserted at the interfaces of the system scattered.

According to a preferred mode of preparation, at least the acyl amino acid or the biologically active molecule is in native form. That is to say that either the acyl amino acid and the biologically active molecule are both under native form, one of which is in native form and the other in the state of salt.

Said amphiphilic compound can also be isolated for use in various therapeutic compositions (tablets, capsules).

The examples given below are in no way limiting. The first three examples relate to methods for obtaining an amphiphilic complex according to the present invention. The fourth example is a permeation study of a compound according to the present invention.

Example 1: Formation of an ion pair between a non-salified hydrophilic active principle (calcitonin) and the non-salified lipoamino acid (oleyl methyl glycine). Two aqueous solutions are used. The first contains calcitonin. Since calcitonin is hydrophilic, the solution is clear. The second solution contains oleyl methyl glycine dispersed in the aqueous phase, the oleyl methyl glycine being sparingly soluble in water. This second solution has a milky white appearance.

After mixing the first and second solutions, a clear solution with a single phase is obtained. The complex obtained, oleyl methyl glycine of calcitonin, is therefore amphiphilic.

Example 2: Formation of an ion pair between a non-salified lipophilic active principle (lidocaine) and the non-salified acyl amino acid (oleyl glycine). Two aqueous solutions are used. The first contains lidocaine dispersed in the aqueous solution. The second solution contains oleyl glycine dispersed in the aqueous phase, the oleyl glycine being sparingly soluble in water. This second solution has a milky white appearance.

After mixing the first and second solutions, both of which are not clear, a solution is obtained. clear with only one phase. The complex obtained, lidocaine oleyl glycine, is therefore amphiphilic.

Example 3: Formation of an ion pair between a salified active principle (polymixin E sulfate) and the non-salified acyl amino acid (linoleyl glycine).

To a solution of polymixin E of sulfate, an NaOH solution is added in an amount necessary to cause all of the polymixin E to precipitate by displacement of the sulfate salt. Polymixin E, also called colistin, thus regains its basic, unsalted structure. The resulting solution, solution B, is therefore an aqueous phase with a precipitate of polymixin E.

An aqueous solution is then used, solution A, comprising linoleyl glycine dispersed in solution A. Since linoleyl glycine is sparingly soluble in water, solution A has a milky white appearance.

Solution A is added to solution B, the solution obtained has only one clear phase. The polymixin therefore resolubilized in the form of an amphiphilic complex, linoleyl glycine from polymixin E.

It should be noted that during the first step, the active principle being salified with a negative ion, the sulphate ion, the precipitation of the active principle in its non-salified form is obtained using a sodium hydroxide solution. In the case where the active principle is salified with a positive ion, precipitation of the active principle in its non-salified form is obtained using a hydrochloric acid solution.

EXAMPLE 4 In Vitro Diffusion Study Through a Synthetic Membrane

An in vitro diffusion study is carried out in order to test the performance of passage of polymixin E through a synthetic membrane. This nylon-type membrane is impregnated with lipid substances, in order to simulate the diffusion through the lipid membrane. intestinal. This study compares the performance of polymixin E in the form of an ion pair with an acyl amino acid (oleyl methyl glycine) and in a form salified by sulphate. The in vitro permeation study was carried out using a Frantz cell. These cells have a donor compartment, in which is deposited a formulation containing polymixin E in the form of an ion pair or a solution of Polymixin E sulfate, and a receptor compartment containing demineralized water. The measurements are carried out in 3 cells at the same time, for each of the forms of polymixin E (polymixin E sulfate or oleyl methyl glycine of polymixin E). The two compartments are separated by the synthetic membrane. The measurement of the quantity of polymixin E which diffuses through the membrane is carried out by UV after: 1 hour, 2.5 hours, 4 hours, 6 hours and finally 7 hours.

The table below shows an amount of polymixin E which has diffused over time; the values presented are cumulative values.

These results show that the ion pair Polymixin E - oleyl methyl glycine diffuses 2 times faster through a synthetic lipid membrane, than in its form salified by sulfate.

Claims

1. Compound for pharmaceutical or cosmetic use consisting of an ion pair complex between an acyl amino acid and a biologically active molecule, used in therapeutic or cosmetic treatments, said complex being amphiphilic.

2. A compound according to claim 1, in which said biologically active molecule is a body of hydrophilic, non-amphiphilic nature, and preferably an organic molecule, a short peptide, a protein, an antigen, a nucleotide or a hormone.

3. A compound according to claim 1, wherein said biologically active molecule is not soluble in water.

4. A compound according to any one of the preceding claims, in which said acyl amino acid results from the condensation between a fatty acid of natural, synthetic or modified origin and a natural, synthetic or modified amino acid.

5. A compound according to claim 4, in which said amino acid comprises at least one amino function in the alpha position relative to the carboxylic acid function.

6. Compound according to any one of the preceding claims, consisting of an ion pair complex between at least one reactive function of the acyl amino acid and at least one reactive function of said biologically active molecule, the reactive function of said biologically active molecule preferably being an acid or amino function.

7. Dispersed system in which the internal dispersed phase is hydrophilic and comprises at least one amphiphilic compound according to one of claims 1 to 6 and in which the dispersing phase is lipophilic.

8. A dispersed system according to claim 7, in which the internal dispersed phase and the dispersing phase contain one or more emulsifying and / or viscosing agents.

9. A method of obtaining a compound according to one of claims 1 to 6, comprising the following steps: - separately preparing a first and a second phase, the first and second phases being miscible or dispersible one in the other, said first phase containing at least one acyl amino acid in the dissolved or dispersed state and said second phase containing at least one biologically active molecule in the dissolved or dispersed state, and - mixing the first phase and the second phase.

10. The method of claim 9, wherein said acyl amino acid and said biologically active molecule are either both in native form, or for one of them in native form and for the other in salt form.