WO2004093886A1

WO2004093886A1 - Topical formulation of ivermectin for the treatment of dermatological conditions

Info

Publication number: WO2004093886A1
Application number: PCT/EP2004/004950
Authority: WO
Inventors: Vincent Manetta; Gary R. Watkins
Original assignee: Galderma S.A.
Priority date: 2003-04-24
Filing date: 2004-04-22
Publication date: 2004-11-04
Also published as: EP1620113A1; BRPI0410503B1; CY2016031I2; AU2004231323B2; JP2012126738A; US8093219B2; US7550440B2; JP2006524212A; US20130209381A1; US20090252797A1; EP1620113B1; US8470788B2; AU2004231323A1; HUS1500048I1; AU2004231323C1; RU2005136438A; US8080530B2; KR20060004667A; MXPA05011208A; JP5711867B2

Abstract

The present invention relates to the use of ivermectin for producing a topical pharmaceutical composition intended for the treatment of rosacea. It also relates to a topical pharmaceutical composition intended for human use, comprising ivermectin.

Description

TOPICAL FORMULATION OF IVERMECTIN FOR THE TREATMENT OF DERMATOLOGICAL CONDITIONS

The present invention relates to the use of ivermectin for producing a topical pharmaceutical 5 composition intended for the treatment of rosacea. It also relates to a topical pharmaceutical composition intended for human use, comprising ivermectin.

Ivermectin is a mixture of two compounds belonging to the avermectin class, 5-0-demethyl-22, 23-

10 dihydroavermectin A_ia and 5-0-demethyl-22, 23- dihydroavermectin An,. They are also known as 22,23- dihydroavermectin Bχ_a and 22-23-dihydroavermectin Bι_b. Ivermectin contains at least 80% of 22,23- dihydroaver ectin Bι_a and less than 20% of 22,23-

15 dihydroavermectin Bi - This active agent is part of the avermectin class, a group of macrocyclic lactones produced by the bacterium Streptomyces avermi tilis (Reynolds JEF (Ed) (1993) Martindale) . The extra pharmacopoeia. 29^th Edition. Pharmaceutical Press,

20 London) .

In the middle of the 1980s, ivermectin was presented as a broad-spectrum antiparasitic medicinal product for veterinary use (W.C. CAMPBELL, et al., (1983). Ivermectin: a potent new antiparasitic agent.

25 Science, 221, 823-828) . It is effective against most common intestinal worms (except tapeworms) , most acarids and some lice. It in particular exhibits considerable affinity for the glutamate-dependent chloride channels present in invertebrate nerve cells and muscle cells. Its binding to these channels promotes an increase in membrane permeability to chloride ions, resulting in hyperpolarization of the nerve or muscle cell. Neuromuscular paralysis which can lead to the death of certain parasites results therefrom. Ivermectin also interacts with other ligand- dependent chloride channels, such as those involving the neuro ediator GABA (gamma-aminobutyric acid) . Ivermectin is more particularly an anthelmintic. It has already been described in humans in the treatment of river blindness caused by Onchocerca volvulus, of gastrointestinal strongyloidiasis (anguillulosis) (product Stromectol®), and of human scabies (Meinking TL et al . , N Engl J Meet 1995 Jul 6; 333 (1) : 26-30 The treatment of scabies with ivermectin) and also in the treatment of microfilaraemia diagnoses or suspected in individuals suffering from lymphatic filariasis due to Wuchereria bancrofti.

US patent 6,133,310 discloses the use of ivermectin topically in the form of a prototype of a lotion consisting of a mixture of ivermectin and water, and also mentions the possibility of a prototype of a cream consisting, for its part, of a mixture of ivermectin and an excipient such as propylene glycol or sodium lauryl sulphate, but describes no pharmaceutical composition as such. These mixtures are similar to experimental preparations used in the context of initial results of proof of concept. In fact, the elements disclosed in that patent give no teaching to those skilled in the art regarding the feasibility of industrially acceptable pharmaceutical compositions containing ivermectin, in particular having good cosmetic properties and a shelf-life which is sufficiently long for an industrial pharmaceutical product (minimum of 2 years) .

Despite the fact that all these uses in humans are limited to oral administration or to the use of experimental preparations, the Applicant has developed a topical pharmaceutical composition intended for the treatment of humans, containing ivermectin. In addition, the Applicant has noted, surprisingly, that the composition according to the invention exhibits very good stability, in particular at different pHs, and good tolerance on the skin. In fact, it is found that it is particularly suitable for the treatment of dermatological conditions, and more particularly well suited to the treatment of rosacea.

A subject of the present invention is also the use of ivermectin for producing a topical pharmaceutical composition intended for the treatment of rosacea, topical pharmaceutical compositions intended for human use, comprising ivermectin, and the use of these topical pharmaceutical compositions for the treatment of rosacea.

The ivermectin according to the invention contains at least 80% of 22, 23-dihydroavermectin B_la and less than 20% of 22, 23-dihydroavermectin B_ib.

The pharmaceutical composition which can be used according to the invention is intended for treating the skin and may be in liquid, pasty or solid form, and more particularly in the form of ointments, creams, milks, pomades, powders, impregnated pads, syndets, towelettes, solutions, gels, sprays, foams, suspensions, lotions, sticks, shampoos or washing bases. It may also be in the form of suspensions of microspheres or nanospheres or of lipid or polymeric vesicles or of polymeric patches and of hydrogels for controlled release. This composition for topical application may be in anhydrous form, in aqueous form of in the form of an emulsion. In a preferred variant of the invention, the pharmaceutical composition according to the invention is in the form of an emulsion of the cream or lotion type, of a gel, or of a solution.

More preferably, the composition according to the invention is in the form of an emulsion.

Conventional emulsions as described in the prior art are unstable virtually homogeneous systems of two immiscible liquids, one of which is dispersed in the other in the form of fine droplets (micelles) . This dispersion is stabilized by virtue of the action of surfactant-emulsifiers which modify the structure and the ratio of the forces at the interface, and therefore increase the stability of the dispersion by decreasing the interface tension energy.

Surfactant-emulsifiers are amphiphilic compounds which possess a hydrophobic component having affinity for oil and a hydrophilic component having affinity for water, thus creating a link between the two phases. Ionic or nonionic emulsifiers therefore stabilize oil/water emulsions by adsorbing to the interface and forming lamellar layers of liquid crystals.

The emulsifier power of nonionic surfactants is closely linked to the polarity of the molecule. This polarity is defined by the HLB (hydrophilic/lipophilic balance) . Conventional emulsions are generally stabilized by a mixture of surfactants, the HLBs of which can be quite different but the proportion of which in the mixture corresponds to the required HLB of the fatty phase to be emulsified.

The composition according to the invention will contain this type of ingredient.

The composition according to the invention is described as a stable emulsion in that it exhibits good physical and chemical stability over time, even at a temperature above ambient temperature (for example 45- 55°C) , as shown in the examples described hereinafter. The ivermectin in the composition according to the invention also, surprisingly, exhibits good chemical stability in the case of pH variation.

The composition according to the invention is advantageously an emulsion which comprises: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) and water. More particularly, the composition according to the invention is an emulsion which comprises: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) one or more gelling agent (s) ; f) and water.

The oily phase of the composition according to the invention may comprise, for example, vegetable, mineral, animal or synthetic oils, silicone oils, Guerbet alcohols or other substances, and mixtures thereof.

As an example of a mineral oil, mention may be made, for example, of paraffin oils of various viscosities, such as Primol 352, Marcol 82 or Marcol 152 sold by the company Esso.

As a vegetable oil, mention may be made of sweet almond oil, palm oil, soybean oil, sesame oil and sunflower oil. As an animal oil, mention may be made of lanolin, squalene, fish oil and mink oil.

As a synthetic oil, mention may be made of esters, such as cetearyl isononanoate sold in particular under the name Cetiol SN by the company Cognis France, diisopropyl adipate, for instance the product sold under the name Ceraphyl 230 by the company ISF, isopropyl palmitate, for instance the product sold under the name Crodamol IPP by the company Croda, or caprylic capric triglyceride such as Miglyol 812 sold by the company Huls/Lambert Riviere.

As a silicone oil, mention may be made of a dimethicone, such as the product sold under the name Dow Corning 200 fluid, or a cyclomethicone, such as the product sold under the name Dow Corning 244 fluid by the company Dow Corning, or the product sold under the name Mirasil CM5 by the company SACI-CFPA. As other fatty substances, mention may be made of fatty acids such as stearic acid, fatty alcohols such as stearyl alcohol, cetostearyl alcohol and cetyl alcohol, or derivatives thereof, waxes such as beeswax, carnauba wax or candelilla wax, and also gums, in particular silicone gums.

The ingredients of the oily phase may be chosen in a varied manner by those skilled in the art in order to prepare a composition having the desired properties, for example of consistency or of texture. The oily phase of the composition according to the invention preferably comprises a synthetic oil and/or a silicone oil; as synthetic oil, isopropyl palmitate such as the product sold under the name Crodamol IPP by the company Croda or isopropyl myristate such as the product sold under the name Crodamol IPM by the company Croda is preferred; as silicone oil, a di ethicone is preferred.

The oily phase of the emulsion according to the invention may be present at a content of between 3 and 50% by weight relative to the total weight of the composition, and preferably between 6 and 20% by weight.

The compositions according to the invention contain surfactant-emulsifiers . Among these compounds, mention may be made, by way of examples, of the glyceryl/PEG 100 stearate sold under the name Arlacel 165FL by the company UNIQEMA or under the name Simulsol 165 by the company SEPPIC; polyoxyethylenated fatty acid esters such as Arlatone 983 from the company UNIQEMA or the polyoxyethylenated (2) stearyl alcohol sold under the name Brij72 combined with the polyethylenated (21) stearyl alcohol sold under the name Brij721 by the company UNIQEMA; sorbitan esters such as the sorbitan oleate sold under the name Arlacel 80 by the company ICI or sold under the name Crill 4 by the company Croda, the sorbitan sesquioleate sold under the name Arlacel 83 by the company ICI or sold under the name Montane 83 by the company SEPPIC, or else sorbitan isostearate; fatty alcohol ethers.

The composition according to the invention advantageously comprises up to 15% by weight of suitable surfactant-emulsifier, preferably from 2 to 12% by weight, and more particularly from 2 to 6% by weight, relative to the total weight of the composition. The composition according to the invention comprises from 0.001 to 10% of ivermectin by weight relative to the total weight of the composition. Preferably, the composition according to the invention contains from 0.1 to 5% of ivermectin by weight relative to the total weight of the composition. By way of example of a solvent and/or propenetrating agent for the ivermectin active agent, mention will preferably be made of propylene glycol, alcohols such as ethanol, isopropanol, butanol, N- methyl-2-pyrrolidone or DMSO, polysorbate 80, phenoxyethanol, and mixtures thereof. The table below illustrates the solubility of ivermectin in various solvents:

The composition of the invention contains from 0.1 to 20%, and preferably from 1 to 10%, of a solvent and/or propenetrating agent for the ivermectin active agent.

The composition according to the invention may also comprise aqueous phase gelling compounds ranging from 0.01 to 5% by weight relative to the total weight of the composition. Among the gelling agents which can be used in the composition according to the invention, mention may be made of carboxyvinyl polymers (carbomers) and, by way of nonlimiting examples, of carbomer, Carbopol 981, Carbopol ETD 2020, Carbopol 980, Carbopol Ultrez 10 NF and Pemulen TRl, sold by the company NOVEON.

As aqueous phase gelling agents, mention may also be made of cellulose derivatives such as, for example, hydroxypropylmethylcellulose or hydroxyethylcellulose; xanthan gums, aluminium/magnesium silicates such as Veegum K or Veegum Ultra resold by Vanderbilt, guar gums and the like, polyacrylamides such as the mixture polyacrylamide/C13-14 isoparaffin/laureth-7, for instance that sold, for example, by the company SEPPIC under the name Sepigel 305, or the mixture acrylamide, AMPS copolymer dispersion 40%/isohexadecane under the name Simulgel 600PHA, or the family of modified starches such as Structure Solanace resold by National Starch, or mixtures thereof.

The composition of the invention preferentially contains from 0.01 to 5%, and preferably from 0.1 to 3%, of gelling agent.

As gelling agent according to the invention, use will preferably be made of carbomers, and preferably Pemulen TRl or aluminium/magnesium silicas such as Veegum K. The composition of the invention also contains water ranging from 30 to 95%, and preferably from 60 to 80%, by weight relative to the total weight of the composition. The water used in the composition according to the invention will preferably be purified water.

The pharmaceutical composition according to the invention may also contain inert additives or combinations of these additives, such as flavour enhancers; preserving agents; stabilizers; - humidity regulators; pH regulators; osmotic pressure modifiers; UV-A and UV-B screening agents; and antioxidants . Of course, those skilled in the art will take care to choose the optional compound (s) to be added to these compositions in such a way that the advantageous properties intrinsically associated with the present invention are not, or are not substantially, altered by the envisaged addition.

These additives may be present in the composition at from 0.001 to 20% by weight relative to the total weight of the composition.

The composition according to the invention is advantageously an emulsion which comprises: a) 6 to 20% of an oily phase; b) 2 to 12% of a surfactant-emulsifier; c) 0.1 to 5% of ivermectin; d) 0.1 to 20% of solvent; e) 0.01 to 5% of gelling agents; f) and water. The pH will preferably be between 6.0 and

6.5. Verification of the natural pH of the mixture and possible correction with a solution of a neutralising agent, and also the incorporation of the optional additives, may be carried out, according to their chemical nature, during one of the steps of the method of preparation, described above.

Examples of compositions which can be used according to the present invention are illustrated in Examples 1 to 6. The subject of the present invention is also a topical composition intended for human use, characterized in that it is an emulsion comprising: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) and water.

More particularly, this composition may comprise: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) one or more gelling agent (s) ; f) and water.

Preferably, the composition comprises: a) 6 to 20% of an oily phase; b) 2 to 12% of a surfactant-emulsifier; c) 0.1 to 5% of ivermectin; d) 0.1 to 20% of solvent; e) 0.01 to 5% of gelling agents; f) and water.

The ingredients being as defined above.

The examples of compositions 1 to 6 illustrate the compositions according to the invention. A subject of the invention is also the use of the composition according to the invention, for producing a pharmaceutical preparation intended to treat dermatological conditions. The use of ivermectin for producing a topical pharmaceutical composition for human use according to the invention is particularly intended for the treatment of rosacea, of common acne, of seborrhoeic dermatitis, of perioral dermatitis, of acneform rashes, of transient acantholytic dermatosis, and of acne necrotica miliaris. The use of ivermectin for producing a topical pharmaceutical composition for human use according to the invention is more particularly intended for the treatment of rosacea. Various formulations of compositions comprising ivermectin, and also results for stability and tolerance obtained with compositions according to the invention, will now be given by way of illustration which is no way limiting in nature.

EXAMPLE 1 : Composition 1

Examples 1 to 4 are realized according to the following procedure:

In a first suitable container, weigh the aqueous phase, mix at 700 rpm and heat to 65°-70°C.

In a second suitable container, weigh the oily phase, mix at 425-475 rpm and heat to 70°-75°C.

In a third suitable container, weigh the active phase and heat to 60-65°C. Where the oily and aqueous phases are at

70 °C, mix the two phases with Rayneri stirring at 900 rpm until complete homogeneity, and then cool.

Allow the emulsion to cool to 55-60 °C, add the active phase with stirring at 600 rpm. Decrease, at 600 rpm, to 30°C.

Adjust the pH to 6.0.

EXAMPLE 2: Composition 2

EXAMPLE 3: Composition 3

EXAMPLE 4: Composition 4

EXAMPLE 5 : Composition 5

Examples 5 and 6 are realized according to the following procedure: - Aqueous phase In a first beaker, disperse the acrylate/clO-

30 alkyl acrylate crosspolymer in water with Rayneri stirring at 800 rpm until a homogeneous gel is obtained. Begin heating up to 65°C-70°C, and then add the glycerol and the additives. - Oily phase

In a second beaker, incorporate the constituents of the oily phase and heat up to 70 °C- 75°C, homogenize with Rayneri stirring at 400 rpm. Active phase In a third beaker, weigh the constituents of the active phase (solvent 4- additives) .

Homogenize at approximately 500 rpm and introduce a magnetic bar.

Weigh the ivermectin in a weighing boat and then introduce it into the beaker container the active phase .

Place this beaker on a magnetic stirrer until the ivermectin has dissolved.

When the oily and aqueous phases are at 70 °C, mix the two phases with Rayneri stirring at 900 rpm for 10 min. Allow the emulsion to cool to 40 °C, add the active phase with Rayneri stirring at 800 rpm for 10 minutes. Decrease at 700 rpm to 30°C.

Make up the volume with a sufficient quantity of water and adjust the pH to 6.3 +/- 0.3.

EXAMPLE 6: Composition 6

EXAMPLE 7 : Example of stability of the compositions described in Examples 5 and 6

Assaying of the active agent by external calibration by HPLC

The results are expressed as % recovery relative to the theoretical value, and demonstrate the very good chemical stability of the ivermectin in the composition as a function of time.

EXAMPLE 8 : Measurement of the chemical stability of ivermectin as a function of pH in the composition of Example 5

These results show the very good chemical stability of ivermectin in the composition as a function of pH.

EXAMPLE 9: Study of tolerance and of acceptability of the composition of Example 5

A randomized single-blind intra-individual study was carried out on 15 individuals with skin tending to be affected by rosacea. The composition of Example 5 was tested in comparison with a gel and with an emulsion having compositions different from the compositions according to the invention.

The individuals presented themselves three times in order to perform the various applications. In the course of each of the visits, 2 of the three products were applied so as to cover each half-face. Each product was tested twice during the study. After application and at each visit, the individuals filled in, for each product tested, a questionnaire for evaluating the clinical tolerance and the cosmetic acceptability.

The following clinical tolerance parameters were evaluated: stinging sensation, burning, dry skin, tightness or itching. The following cosmetic acceptability parameters were evaluated: creaminess, texture, lack of a sensation of greasy and sticky skin, nourishing nature, feeling of comfort and of softness to the touch.

For all the tolerance parameters, the composition according to the invention was judged to be well tolerated by the individuals, to the same extent as the two other compositions.

In general, for all the acceptability parameters, the individuals gave their approval (good or excellent) , with respect to the parameters, regarding the composition of the Example 5 in 76.66% of the cases where it was tested. This formulation therefore tends to distinguish itself from the gel- cream composition, having a 66.66% approval, and from the other emulsion, having a 63.32% approval.

EXAMPLE 10: Study of irritation over 21 days

A study of irritation over 21 days was carried out in order to test the irritation induced by the three compositions tested in the preceding example. No product was considered to be irritant under the conditions tested.

Claims

1. Use of ivermectin for producing a topical pharmaceutical composition intended for the treatment of rosacea.

2. Use according to Claim 1, characterized in that the composition is in the form of an emulsion of the cream or lotion type, of a gel or of a solution.

3. Use according to Claim 1 or 2, characterized in that the composition is in the form of an emulsion.

4. Use according to any one of Claims 1 to

3, characterized in that the composition comprises from 0.001 to 10% by weight of ivermectin relative to the total weight of the composition.

5. Use according to any one of Claims 1 to

4, characterized in that the composition is an emulsion which comprises: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) and water.

6. Use according to any one of Claims 1 to

5, characterized in that the composition is an emulsion which comprises: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) one or more gelling agent (s); f) and water.

7. Use according to any one of Claims 1 to

6, characterized in that the composition according to the invention comprises: a) 6 to 20% of an oily phase; b) 2 to 12% of a surfactant-emulsifier; c) 0.1 to 5% of ivermectin; d) 0.1 to 20% of solvent; e) 0.01 to 5% of gelling agents; f) and water.

8. Use according to any one of Claims 5 to

7, characterized in that the oily phase comprises a synthetic oil and/or a silicone oil.

9. Use according to Claim 8, characterized in that the synthetic oil is isopropyl palmitate or isopropyl myristate.

10. Use according to any one of Claims 5 to

9, characterized in that the surfactant-emulsifier is chosen from glyceryl/PEGlOO stearate, polyoxyethylenated fatty acid esters, polyoxyethylenated (2) stearyl alcohol combined with polyethylenated (21) stearyl alcohol, sorbitan esters, such as sorbitan oleate, sorbitan sesquioleate or sorbitan isostearate, and fatty alcohol ethers.

11. Use according to any one of Claims 5 to 10, characterized in that the solvent is chosen from propylene glycol, alcohols such as ethanol, isopropanol, butanol, N-methyl-2-pyrrolidone or DMSO, polysorbate 80, phenoxyethanol, and mixtures thereof.

12. Use according to any one of Claims 6 to 11, characterized in that the gelling agent is chosen from carbomers or aluminium/magnesium silicas.

13. Use according to any one of the preceding claims, characterized in that the composition comprises in water:

as % by weight relative to the total weight of the composition.

14. Use according to any one of the preceding claims, characterized in that the composition comprises in water:

as % by weight relative to the total weight of the composition.

15. Topical composition intended for human use, characterized in that it is an emulsion comprising: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) and water.

16. Composition according to Claim 15, characterized in that it comprises: a) an oily phase comprising fatty substances; b) at least one surfactant-emulsifier; c) ivermectin; d) one or more solvent (s) and/or propenetrating agent (s) for the active agent; e) one or more gelling agent (s) ; f) and water.

17. Composition according to Claim 15 or 16, characterized in that it comprises: a) 6 to 20% of an oily phase; b) 2 to 12% of a surfactant-emulsifier; c) 0.1 to 5% of ivermectin; d) 0.1 to 20% of solvent; e) 0.01 to 5% of gelling agents; f) and water.

18. Composition according to any one of Claims 15 to 17, characterized in that it comprises in water:

as % by weight relative to the total weight of the composition.

19. Composition according to any one of Claims 15 to 17, characterized in that it comprises in water:

as % by weight relative to the total weight of the composition.

20. Use of the composition according to any one of Claims 15 to 19, for preparing a medicinal product intended for the treatment of dermatological conditions .

21. Use according to Claim 20, characterized in that the medicinal product is intended for the treatment of rosacea, of common acne, of seborrhoeic dermatitis, of perioral dermatitis, of acneform rashes, of transient acantholytic dermatosis, and of acne necrotica miliaris .

22. Use according to either of Claims 20 and 21, characterized in that the medicinal product is intended for the treatment of rosacea.