WO2013139927A1

WO2013139927A1 - Composition for the treatment of pediculosis and corresponding manufacturing process

Info

Publication number: WO2013139927A1
Application number: PCT/EP2013/055966
Authority: WO
Inventors: Pierre-Yves DUHOT
Original assignee: Omega Pharma Innovation & Development Nv
Priority date: 2012-03-22
Filing date: 2013-03-21
Publication date: 2013-09-26
Also published as: WO2013140367A3; BE1020154A5; RU2014140542A; EP2836071A1; WO2013140367A2

Abstract

-The invention relates to a composition for the treatment of human or animal pediculosis including at least one first active principle having filmogenic properties and which is designed to cover, at least partially, at least one parasite responsible for said pediculosis, to prevent the latter from breathing, said composition being characterized in that said at least one active principle is encapsulated in at least one globule whose size is designed to allow said globule to penetrate into the breathing orifices of said at least one parasite and its eggs. -Treatment of human or animal pediculosis.

Description

COMPOSITION FOR THE TREATMENT OF PEDICULOSIS AND CORRESPONDING MANUFACTURING PROCESS

TECHNICAL FIELD

The present invention refers to the general technical field of products for topical use, used in particular on the skin and/or scalp, and which can have, for instance, a solid, fluid, pasty or liquid, semiliquid or semi-pasty, gel, powder or foam form.

This invention refers more particularly to compositions intended for the treatment of human or animal pediculosis, in particular pediculosis caused by lice and/or nits that may appear, for instance, in human hair. The present invention concerns a composition for the treatment of human or animal pediculosis containing at least one active principle having filmogenic properties and designed to cover, at least partly, at least one of the parasites responsible for said pediculosis, to prevent the latter from breathing.

The present invention also concerns a manufacturing process of a composition for the treatment of human or animal pediculosis including at least one active principle having filmogenic properties and designed to cover, at least partly, at least one parasite responsible for said pediculosis, to prevent the latter from breathing.

The present invention also refers to a lotion for the treatment of pediculosis in humans or animals. The present invention also concerns a system for the treatment of human or animal pediculosis.

The present invention also refers to the use of at least one first active principle having filmogenic properties in a composition designed for the treatment of human or animal pediculosis. The present invention finally concerns a process for the treatment of human pediculosis in the course on which a composition is used including at least one said first active principle having filmogenic properties and designed to cover, at least in part, at least one of the parasites responsible for said pediculosis, to prevent the latter from breathing.

PRIOR ART

From the environmental and epidemiological standpoint, it is known that lice are hematophagous, anoplourous insects that are strict parasites of man. There are three species of lice belonging to two types: Pediculus humaus capitis, Pedicullus humanus corporis and Phtirus pubis, respectively responsible for pediculosis of the scalp, pediculosis of the body and pubic pediculosis. Pediculus humanus capitis, also referred to as the "head louse" lives only on the scalp of man where it is nourished and on the hair on which it lays eggs whereas Pedicullus humanus corporis also referred to as the "body louse" is fed from the remainder of the body and also lives in the folds of clothing that is not properly washed or unwashed.

Generally, a female lives approximately 1 month during which it lays approximately 200 to 300 nits. Conventionally, the louse nourishes itself between 2 and 3 times per day, sucking in blood through its mandibles and injecting anti-coagulating saliva. It is incapable of fasting for more than 2 days, for instance on unworn clothing or unoccupied bedding.

However, lice can resist extended immersion thanks in particular to an "immersion reflerf' rendering the current washing of the hair inefficient. Conversely, the louse is destroyed by dry heat or hot water at 50°C in 30 minutes. Mineral oil and petrol can also kill lice by asphyxia to some extent, but has low efficiency on nits. Today, despite the fact that treatment exists based on the chemical insecticides and improved hygiene, head lice continue to appear all over the world. Pediculosis is cosmopolitan and appears at every social stratum. Its prevalence has increased since the 70s in many countries. Pediculosis is an endemic ailment in early childhood collectivities, in particular between ages 6 and 8 years, sometimes evolving into an epidemic.

A child infected by untreated lice is sufficient to contaminate one or several other children. This makes it particularly difficult to get rid of these parasites globally. Scratching one's head, especially for a child, is often considered as the first clinical sign of lice infestation. The sores are caused by the movements of insects between the hair and especially to their repeated bites, in the course of which they inject an irritating saliva. The dejections of the lice are also responsible for irritation or allergic reactions. Pediculosis can sometimes generate social and psychological problems with tiredness and irritability due to difficult sleep.

This makes it essential to treat all the carriers of these ectoparasites in man. For this purpose, there is a well known embodiment which consists in neurotoxic treatment of the nervous system of the lice to destroy them.

Among these neurotoxic treatments, one known method is malathion, forming part of the organophphorates family used particularly in the definition of combat gases during World War II. These molecules, irreversible anticholinesterasic derivatives, inhibit the synaptic conduction of the nervous system of the parasites, and are pediculicidal and partially ovacidal. More particularly, for treatment based on malathion, two applications are mandatory, applied at an interval of one week, partly because of the inefficiency of the product on young nits (1 to 3 days after laying) which do not yet have a developed nervous system.

Although they are efficient in eradicating lice, these molecules are nevertheless dangerous to man and can cause serious poisoning with digestive signs (nausea, vomiting, and diarrhea) and muscarinic signs (myosis, hypersialorrhea hypotension, and bradycardia).

In addition, malathion which is generally used in a form having a high alcohol concentration representing a risk of scalp irritation or even burns, with an odor that may be unpleasant to certain patients, sometimes causing real problems of keeping to the treatment. In addition, it has been demonstrated by certain scientific studies that malathion under certain conditions could be a mutagenic, carcinogenic agent and could even be associated with several cases of infantile leukemia.

Alternatively, treatment based on pyrethrin and pyrethroids which are natural or synthetic molecules, more degradable and in theory safer in use than malathion are also employed. Treatment based on pyrethrins also requires two applications at an interval of one week, because the product is ineffective on young nits (1 to 3 days after laying).

This means that between two applications, the subject remains potentially infected and infecting. In addition, a third application may sometimes be necessary, inevitably lengthening the complete treatment time.

There are also organochlorines which are neurotoxic to the parasites and older, like lindane, hexachlorocyclohexane or DDT, for louse treatment. However, these pediculicidal treatments are less efficient and have a low ovacidal effect. In addition, for several years now, there have been cases of resistance to organochlorines (lindane, DDT). Accordingly, these products are simply an accessory in terms of pediculosis treatment.

Thus, most of the current neurotoxic treatments as referred to above are potentially irritating and aggressive to the scalp. In addition, these treatments usually have to re- applied several times to obtain a cure, in particular in their effect on nits. What is more, these chemical treatments generate increasing levels of resistance among the louse to most of the current neurotoxic insecticides.

There are also specialties combining malathion and pyrethrins proposed as a response to the appearance of resistance. However, in addition to the fact that there is no real consensus of opinion regarding this effect, the proposed application time of the product (one hour) is barely compatible with the optimal therapeutic effect of malathion.

In addition, the appearance of resistance to pyrethrins and secondly to malathion, combined with the aforementioned side effects and the enlarging wariness of the public and health authorities regarding chemicals, especially neurotoxic insecticides, has limited the use of these compounds in the fight against global pediculosis.

Therapeutic alternatives have been proposed, more particularly mechanical treatment based on fats like Vaseline or certain oils whose action is based on the capability of asphyxiating the parasites. These are referred to as "smothering" treatments. Accordingly, the treatment used as an initial intent is Vaseline, despite the difficulties relating to its use, for instance, the fact that it sometimes takes a week, with one shampoo per day, to get rid of the Vaseline applied to the scalp.

This situation has prompted the appearance of alternate proposals such as treatments based on fatty matter: silicones, paraffins or coco and soy vegetable oils.... The action mechanism of this treatment is based on its capability to obstruct the breathing passages of the lice, causing their asphyxiation in a few hours.

However, although these approaches may be satisfactory in terms of their efficiency on the louse, the appearance of resistance in the louse, of toxicity and harm to man and the environment, means that they also represent certain drawbacks. In particular, they are not efficient enough on nits, requiring several treatments to eradicate lice.

Because all the aforementioned products have less efficiency on nits, it means that they must be reapplied between 7 and 10 days after initial application. This period is required for the nits to hatch and the young lice which alone are sensitive to these substances to appear. During this long but essential waiting time between two applications, the subject continues to be infested and contagious for people around them or for infantile communities.

In addition, many of these fats are refused by users and there was a risk of a lower observation level, because of their disagreeable cosmetic aspect. SUMMARY OF THE INVENTION

Accordingly, the specific objects of this invention aim at remedying the various drawbacks listed above and proposing a new composition for the treatment of pediculosis, efficient both on the parasites and their eggs. Another object of the invention referred to is to propose a new composition for treating pediculosis which is efficient in a single application and which avoids any risk of contagion by the subject during treatment.

Another object of the invention is to propose a new composition for treating pediculosis offering a new method of dealing with communities of children (schools, vacation camps, etc.) in order to treat an entire collective group simultaneously.

Another object of the invention is to propose a new composition for the treatment of pediculosis, avoiding recourse to the neurotoxic insecticides.

Another object of the invention is to propose a new composition for the treatment of pediculosis offering a real advantage in terms of pediculicidal and ovacidal efficiency but also in terms of its moisturizing and soothing capability for the scalp.

Another object of the invention is to propose a new composition for the treatment of pediculosis which is efficient, agreeable and easy to use by the greatest number of people. Another object of the invention is to propose a new composition for the treatment of pediculosis which avoids the irritation of parasite bites and repeated scratching.

Another object of the invention is to propose a new composition for the treatment of pediculosis whose formulation uses easily available and low-cost compounds.

Another object of the invention is to propose a new process for the manufacturing of a composition for the treatment of pediculosis including specific and controlled steps to obtain a composition which is efficient on the parasites and on their eggs.

Another object of the invention is to propose a new process for manufacturing a composition for the treatment of pediculosis, including steps that are easily implemented. Another object of the invention is to propose a new lotion for the treatment of pediculosis which is efficient both on the parasites and their eggs. Another object of the invention is to propose a new system of treatment for pediculosis which is efficient both on the parasites and their eggs.

Another object of the invention is to propose a new system for the treatment of pediculosis which is efficient in a single application and which includes fast and easily implemented steps at the individual or collective level.

Another object of the invention is to pose a new use of at least one first active principle having filmogenic properties in a composition to treat pediculosis which is efficient both on the parasites and their eggs.

Another object of the invention is to propose a new process of treatment for pediculosis which is efficient both on the parasites and their eggs.

Another object of the invention is to propose a new process of treating pediculosis which is efficient in a single application, including simple steps that are easily implemented by any user.

The objects assigned to this invention are achieved by a composition for the treatment of human or animal pediculosis including at least one first active principle having filmogenic properties and designed to cover, at least partly, at least one of parasite responsible for said the pediculosis in order to prevent it from breathing, said composition being characterized in that said first active principle is encapsulated in at least one globule whose size is designed to allow the penetration of said globule into the breathing orifices of said at least one parasite and its eggs.

The objects assigned to this invention are also achieved by means of a manufacturing process of a composition for the treatment of human or animal pediculosis including at least one first active principle having filmogenic properties and designed to cover, at least in part, at least one parasite responsible for said the pediculosis in order to prevent it from breathing, said manufacturing process being characterized in that it includes a stage of encapsulation of said at least first active principle in at least one globule whose size is designed to allow the penetration of said globule into the breathing orifices of said at least one parasite and its eggs. The objects assigned to this invention are also achieved by a lotion for the treatment of pediculosis in man or animal, including a composition as mentioned above.

The objects assigned to this invention are also achieved by a system for the treatment of pediculosis in man or animal comprising: - a composition conforming to the above,

- a system for removing the dead parasites.

The objects assigned to this invention are also achieved by the use of at least one first active principle, having filmogenic properties which is encapsulated into at least one globule whose size is designed to allow the penetration of said at least one globule into the breathing orifices of at least one parasite and the eggs of the latter, in a composition for the treatment of human or animal pediculosis.

The objects assigned to this invention are finally achieved by means of a process for the treatment of pediculosis in man, in the course of which use is made of a composition including at least one first active principle having filmogenic properties and designed to cover, at least partly, at least one parasite responsible for said pediculosis to prevent it from breathing, said process being characterized in that it includes a step of penetration of said at least first active principle, which is encapsulated in at least one globule, into the breathing orifices of said at least one parasite and its eggs, size of said globule being designed to allow said penetration into said breathing orifices of said at least one parasite and its eggs.

BEST MANNER OF PERFORMING THE INVENTION

This invention concerns a composition for the treatment of human or animal pediculosis and in particular the treatment of ectoparasites of man, more especially lice and nits. Preferably it is in the form of a fluid designed for application to the human and/or animal body. The composition of the invention therefore advantageously takes on a liquid or semiliquid form and has a mechanical pediculicidal and ovacidal action. It is easy to apply and designed on the one hand to act against lice, and also against nits. Preferably, this composition is used as a single application dose without recourse to the use of a neurotoxic insecticide like those normally used in the fight against pediculosis (permethrin, malathion, etc.) Indeed, it is advantageously designed for monodose pediculicidal and ovacidal treatments, in particular for the treatment of lice on man, by a single application to the surface of the scalp and hair of man.

In the continuation of the description an endeavor will be made to describe an embodiment of the invention that is particularly advantageous in which the composition consists of a conventional louse lotion and allows the total eradication of lice and nits from man's hair.

The composition includes at least one first active principle having filmogenic properties and designed to cover, at least partly, at least one parasite responsible for said pediculosis, to prevent said parasite from breathing.

Said at least first active principle is encapsulated in at least one globule whose size is designed to allow said globule to penetrate into the breathing orifices of said at least one parasite and its eggs.

Therefore, the advantage of the composition is its efficiency as a single application using globules calibrated according to the size and anatomy of the breathing systems of the parasite in its various stages of development. These globules have the property of penetrating through the spiracles, the breathing orifices and/or articulations of the parasites, of protecting and transporting the first active principle through the respiratory orifices of lice and nits. The first active principle acts by creating a hermetically sealed film once dry, preventing gas exchanges and therefore breathing. The first active principle is transported and distributed through the breathing system of the parasite by means of protective globules.

In an advantageous manner, each globule presents substantially a size which is smaller than the size of the breathing orifices of the parasite and its eggs, preferably included approximately between 1 and 10 μητι, preferably included approximately between 5 and 9 μΐη. Advantageously, these globules are more or less identical to each other and are calibrated in size. Preferentially, the globule includes at least one more or less water-dispersible wall enclosing said first active principle, which wall is designed to evaporate, at least partially, to allow said first active principle first to come out, in a more or less fluid form, of the inside of the parasite through its pores, and also to solidify as a film around said the parasite and its eggs, to prevent the latter from breathing and cause their death. In other words, the wall of the globule is continuous in order to dissolve or evaporate or disappear once it reaches the parasite, in particular by evaporation. This allows the active principle to assume a more or less fluid form and spread outside the parasite to create, as it dries, a more or less sealed film around it.

Preferably, the globules are capsules or microcapsules, preferably having a more or less rounded, spherical or ovoidal shape, consisting of a core that is more or less liposoluble enclosed by a wall of a more or less water-dispersible nature, preferably subdivided into an outer wall that is more or less hydrophile and an inner wall that is more or less hydrophobic. Advantageous use is made of at least one surfactant or emulsifying agent to keep the globule stable, in particular on the wall around the first active principle.

Advantageously, the first active principle contains at least one liposoluble compound chosen from the following compounds: vegetable oil, mineral oil, mineral oil substitutes, silicones and triglycerides. In addition, the composition of the invention includes at least one second active principle designed to act directly on the parasite and its eggs. Preferably, the second active principle includes at least one liposoluble essential oil. Advantageously, this liposoluble essential oil will be chosen from among: melaleuca essential oil, matricaria essential oil, lavender essential oil, thyme essential oil, rosemary essential oil or any other essential oil.

The second active principle is associated with the first active principle and advantageously has a complementary action to the latter. In particular, the essential oils used advantageously have a more or less insecticidal action and/or an action on the cuticle of the parasite. For instance, the second active principle is designed to soften the cuticle of the parasite, to weaken it, and to accentuate the destruction of said parasite when combined with the action of the first active principle.

In a preferred embodiment of the invention, the globules of the invention, advantageously called "Oxyphthirine®", includes said first and second encapsulated active principles, preferably a mixture of natural triglycerides, isohexadecane, paraffin, a complex of essential oils (melaleuca, matricaria, lavender, thyme, rosemary...) and water.

More specifically, the action mechanism of the proposed product is based on the specific characteristics of the breathing system of insects that are ectoparasites of man in particular Pediculus humanus and insects generally having a length of less than 5 cm. These insects "breathe" through orifices on the sides of the thorax and abdomen (generally a pair of orifices per anatomic segment, called spriracles. These spiracles work like valves and are the door to the breathing system distributing oxygen to the insect's hemolymph. These valves can close entirely when the insect is no longer in an aerial medium but immersed in water, in a fatty matter or in another liquid. This triggers an effect of apnea, generally called "immersion reflex" causing the spiracles to close and the insect to enter a state of suspended life.

However, the absence of any oxygen being drawn in through the spiracles for a period of 4 hours, a. period liable to vary between 4 and 24 hours depending on the insect or parasite, causes the death of the insect by asphyxia. In practice, when the composition of the invention, that is, advantageously a louse or nit treatment product with a mechanical action, is applied to the zone infested by Pediculus humanus (cf. scalp, pubis, animal coat or any other hairy area) and after entering the breathing system of the parasite, rises and definitively blocks the spiracles of Pediculus humanus. The phenomenon of the asphyxia of the parasite, in particular the louse, thanks to the composition of the Invention, takes place in two steps as described below.

In the course of the first step, the louse is immersed in a fluid emulsion such as oil in water or water in oil. The solution then penetrates deeply into the breathing system by capillarity or by the mechanical action of the natural breathing in the parasite. The reflex of the louse is then to cover its spiracles (breathing orifices) throughout the immersion time, to protect itself from the aqueous medium. This stage prevents it from breathing momentarily. The louse is only able to resist this anaerobic situation for a few hours. It is a simple matter of maintaining this state for more than 8 hours to kill the parasite. During the second stage, the aqueous volatile part of the mixture evaporates at the surface of the insect. The product of the invention with its filmogenic properties is then modified and changes from an initial semiliquid state to a semisolid state thanks to spontaneous desiccation favored by the heat from the scalp at approximately 35°C. It then forms a hermetically sealed and flexible residual wall which totally envelopes the parasite in its smallest asperities.

Accordingly, the ideal formulation for the pediculicide composition on the invention, by penetrating the breathing system on the one hand and by covering all the spiracles of the louse without exception, definitively asphyxiates the parasites.

The phenomenon of the asphyxia of the nit is more complex than that of the louse. Accordingly, the generation of an innovative galenic element called the "meta-emulsion" efficiency destroys the louse and the nit. Indeed, the larvae, protected by the outer shell of the nit, are difficult to reach by any fluid, whether watery or even more so oily. Gas exchanges with the outside are almost nonexistent during the first days and are always passive since the larva is barely beginning its development. There is no active mechanical breathing and it is impossible for the larva to inhale any fluid during its development that could reproduce the mechanism of asphyxia previously described for the louse. However, our observations have revealed that the shell has a cap enabling the larva to exit once it has reached maturity (between 7 and 10 days after laying) and that this cap has approximately 16 holes in it, each measuring approximately 15 μηη and behind which there is a filter matrix or grille. Close study was paid to the structure of this matrix and the size of the holes in the cap.

The particular galenic aspect of the invention composition, that is the meta-emulsion, makes it possible to generate globules of a calibrated size included between the 5 and 9 μητι, thus allowing passage through the cap via the holes in the louse and the nit. Once the product has entered the inside, filling all or part of the nit's cavity, and in particular by entering the internal matrix, it advantageously blocks not only the gas exchange system but also the hatching system of the nit.

After desiccation, the composition of the invention operates according to the same principle of solidification as on the louse. The composition then enters a semisolid state which is occlusive and hermetically sealed, making it impossible for the nit to breathe or to hatch. Once dry, the composition preferably blocks the opening mechanism of the cap (a sort of spring naturally pushing against the cap) when the larva, transformed into a young louse, reaches maturity. If the young louse manages to survive its asphyxia, it no longer has any way of getting out of its shell, remaining captive in it and being unable to infest the subject or contaminate other people.

Thus, the globules of the invention are preferentially designed to act indifferently and jointly on adult parasites, their eggs, their larva and their nits in a particularly efficient manner, because of their sizes that are specifically designed for the size of the breathing orifices on the various targeted organisms.

Preferably, calibrated meta-emulsion globules are used as vectors for delivering the active principle(s) gradually as they penetrate the respiratory system of the lice and nits.

Any semiliquid formulation tolerated by the scalp (in particular of the child) and containing a certain quantity of water is theoretically interesting as a mechanical louse and nit treatment of the invention. These formulations can take any currently known galenic aspect, such as gels, emulsions, foams, lotions, creams, sprays, etc., in a non- limitative manner. However although the galenic aspect of the composition is secondary with respect to its efficiency against lice, it does have a great bearing on its use of application. The pediculicide composition of the invention allows easy and agreeable application to the scalp without it being greasy or oily in appearance. Dissemination through the hair must be easy and the hair must be easy to comb without any risk of the product being eliminated. This makes formulations that are too solid less interesting (gels, creams, ...). On the other hand, formulations that are too liquid do not hold well enough to adhere to the root of the hair and to the scalp.

Generally, shampoos are less efficient because of the insufficient contact time and the dilution of the active principle. Sprays do not offer sufficient covering capability. Because they are projected in jets, they form shadow areas not reached by the product.

Experience reveals that even massaging the treated area is not sufficient to spread out the product suitably when released as a spray. The main reason is that the product has to be put into a solution to become sufficiently fluid for expulsion as microdroplets. But excessively fluid formulations do not have sufficient physical and galenic properties to adhere suitably to the surface of the lice. Sprays leave a residue which is variably thick and heterogeneous when dry. This aspect tends to make the asphyxia of the parasites less efficient.

The profit to risk ratio of aerosols has been reevaluated because of the death of an asthmatic child (probable bronchospasm). L'Agence Francaise du Medicament decided after obtaining the opinion on the National Pharmacovigilance Commission to counter- indicate aerosols in this field. Aerosols are no longer to be used. Powders must be used exclusively for treating fabrics.

Accordingly, the composition of the invention advantageously takes the form of a lotion because it allows correct adherence to the hair and uniform spreading over the scalp, in particular when the hair is worn long, much appreciated by the people concerned. However, it is certainly possible that another presentation as described previously or not is considered, without it being outside the scope of this invention.

The pediculicide composition of the invention is preferably transparent or translucent to facilitate the examination of the treated area. It is advantageously designed to dry and be eliminated easily when dry, by gentle combing or rinsing in water. Furthermore, preferentially, the composition of the invention is invisible when dry, is odorless and does not stain clothing. Further, the composition is advantageously designed to be moisturizing and soothing to the scalp, a definite novelty compared to insecticidal products which are too often irritating. According to the specific embodiments of the invention, non-aqueous ingredients such as fatty matter, triglycerides, silicones, polymers, Span, Tween, essential oils, etc., will form residues also penetrating into the breathing system of the lice and the matrices inside the cap of the nits, in such a way as to be deposited on all the outer surfaces of the parasites and the inner surfaces of the respiratory systems.

The composition of according to the invention will advantageously trigger the apnea of the parasite and, after penetration into the respiratory system in depth, will result in its asphyxia and therefore its death.

The water and fats are not miscible in all proportions meaning that the meta-emulsion galenic composition of the invention has the twofold technical advantage of emulsifying the two substances into globules on the one hand, and of allowing the calibration of the globules at around 5-9 μηη.

The present invention also concerns a manufacturing process of a composition for the treatment of human or animal pediculosis. This composition is advantageously and approximately compliant with that described previously and includes at least one first active principle with filmogenic properties, designed to cover, at least partly, at least one the parasites responsible for said pediculosis, to prevent the latter from breathing.

The manufacturing process of the invention includes the encapsulation of said at least first active principle in at least one globule whose size is designed to allow the penetration of said globule into the breathing orifices of said at least one parasite and its eggs.

In the present invention the globules are lipidic and formulated by a process of a multiplication by phase inversion caused by the passage of the emulsion to beyond the phase inversion temperature, preferentially on the basis of the process described in the French patent application FR-2 849 379. Advantageously, this process preserves the active principle by incorporating it in the continuous oily phase, therefore without contact with the aqueous phase, beyond the phase inversion temperature. Indeed, the incorporation of the liposoluble active principle into the formulation at a temperature above the phase inversion temperature, that is when emulsion is in the continuous oily phase (water emulsion in oil), produces good distribution of the active principle in the oily phase, limits its contact with the aqueous phase, and surprisingly, although the temperature is high, the dwell time at the temperature being very short because the incorporation is followed by the soaking of the emulsion, degradation phenomena are minimized or eliminated.

Therefore, preferentially, the present invention concerns a process for the encapsulation of the liposoluble active principle in the globules. In an advantageous manner, the encapsulation stage includes a substage for the manufacturing of the emulsion during which: a) an aqueous phase and a fatty phase are prepared, b) the temperature of the two phases is increased to a temperature above the phase inversion temperature, c) the two phases are mixed, d) the first liposoluble active principle is added to the liposoluble phase, e) the temperature is reduced to the phase inversion temperature, f) after phase inversion and the obtaining of a continuous aqueous phase emulsion, the emulsion obtained is soaked to bring down its temperature. In a preferable manner, the process includes a sub stage c) designed to reduce the temperature to a temperature immediately above the phase inversion temperature.

In an advantageous manner, stage c) is carried out before stage b), meaning that the two phases are mixed before the temperature reaches the phase inversion value. In addition, during substage c), the first active principle is advantageously dissolved in a fatty phase complement before being incorporated into the liposoluble phase.

The emulsion obtained through this process is preferably a meta-emulsion which is then put through a concentration substage in the course of which the aqueous phase is partly eliminated. Advantageously, the concentration substage is obtained by a conventional concentration method, for instance tangential ultrafiltration.

The process of inversion can advantageously be implemented according to various embodiments, for instance by reducing the temperature to a temperature immediately above the phase inversion temperature before the incorporation of the first active principle. Reducing the temperature in this way can be obtained advantageously naturally, or when triggered by the man of the art. It is also entirely acceptable to carry out "soaking" to favor the reducing of the temperature.

The meta-emulsion obtained in the course of substage f) includes globules more or less rounded in shape with size included approximately between 1 and Ι Ο μηη, preferably included approximately between 5 and 9 μηη.

In addition, the meta-emulsion obtained in the course of substage f) is designed to a monodose pediculicidal and ovacidal treatment, in particular for the treatment of lice in man. According to the invention, stage f) of soaking is carried out by adding an aqueous phase complement brought to a temperature at the least below the phase inversion temperature and possibly below the ambient temperature. This stage of abrupt and fast cooling reduces the temperature of the emulsion and the exposure time of the active principle to a higher upper temperature. This soaking can also be carried out with a cooling system by thermal exchange or by the addition of a liquefied gas, for instance nitrogen.

The immediately higher temperature refers to the phase inversion temperature higher by a few degrees, in practice 1 or 20°C than the phase inversion temperature. The system of phase inversion of temperature has been determined previously by system conductivity monitoring or by individual observation.

It is advantageous that the fatty phase of the process includes approximately between 1 and 35 % of fatty matter, preferably between approximately 5 and 30 %, whereas the aqueous phase includes between 35 and 99 % of water, preferably between approximately 45 and 92 %.

Preferably, this fatty phase whose composition directly affects the calibration of the globules, includes fats of a paraffin or triglyceride type, or derivatives and/or complexes of paraffin and/or triglycerides. The choice of the fatty matter is made advantageously depending on the nature and polarity of the first liposoluble active principle to be encapsulated.

In a previous embodiment, the fats are chosen from mineral or vegetable oils, or from mineral oil substitutes such as isohexadecane, silicones in particular cyclometh icons or polydimethylsiloxane, or triglycerides, to maintain the lowest possible phase inversion temperature.

The first active principle is more or less identical to that described previously, that is, preferentially, a liposoluble compound chosen from between vegetable oils, mineral oils, mineral oil substitutes, silicons and triglycerides. Preferably, this process also allows encapsulation in the globules of at least one second active principle. Advantageously, the second active principle is more or less identical to the one described previously, for instance, at least one liposoluble essential oil chosen from among: melaleuca essential oil, matricaria essential oil, lavender essential oil, thyme essential oil, rosemary essential oil or any other essential oil. The process of the invention involves other ingredients liable to improve the meta- emulsion of the invention, for instance, emulsifiers, surfactants, antioxidants, preservatives, of which the list is not exhaustive.

It might also be advantageous to use water soluble surfactants for instance, glycol esters, glycerol, itol, sorbitan, glycol polyethylene.... Alternatively, surfactants of a lipophile nature could well be used.

The process of the invention also uses preferably emulsifiers such as, for instance, monoglycerol esters, polyglycerol esters and fatty acids, silicones such as cetyl dimethicone copolyol, polyhydroxystearic acid esters and glycol polyethylene; this list is not exhaustive.

Salts or other ingredients may also be added to either of the aforementioned fat and gas and aqueous phases, for instance, preservatives and/or antioxidants, for instance 30 butylhydroxylanisol (BHA), butylhydroxytoluene (BHT), propyl gallate, 1 'cx-tocopherol, EDTA, 1 'cx-tocopherol and/or EDTA.

In the process according to the invention, we detect phase inversion either by the display of the composition whose appearance changes, or by measuring the conductivity. The control of the various substages of the process and the different ingredients and active compounds involved in the two phases allows us to obtain an invention composition including calibrated globules capable of entering the breathing orifices of the parasites and their eggs, in particular, lice and nits.

This invention also concerns, as an intervention in its own right, a lotion for the treatment of pediculosis in man or animal including a composition conforming to the above. Advantageously, this lotion is a pediculicidal and lenticidel lotion for the treatment of lice on the scalp and in the hair of man. Preferably, said lotion is packed in a conventional capillary lotion flask, or for instance, in a plastic bottle, more or less opaque, rigid and strong. Several examples representing the pediculicidal composition of the invention, in accordance with the aforementioned process, is presented as a purely illustrative and non-limiting means, in the continuing description:

EXAMPLE 1 :

Two phases are prepared with the following ingredients: - For the fatty phase: 35 % Cetiol SN PH, AMI-Cognis, 20 % Cetiol V PH, AMI-Cognis, 19.35% paraffin oil, B2Aiglon (Paraffinum liquidum)/Paraffinum Perliquidium,

- For the aqueous phase: 25% of demineralized water. The fatty phase corresponds more or less to the first active principle of the globules described above.

These two phases are heated to a temperature of 85°C and combined by the addition of the aqueous phase to the fatty phase with 700 rpm shearing stirring. A second active principle based on essential oils is added. It contains 0.2 % of melaleuca essential oil, 0.2 % of matricairia essential oil, 1 .5 % of lavender essential oil, 0.05 thyme oil and 0.05 % rosemary oil. In a solution of hexanoic acid triglyceride, this second active principle is then incorporated into the emulsion obtained by mixing the aqueous phase and the fatty phase at a temperature of around 81 °C. The phase inversion of detained at 73°C is identified by increasing the conductivity to above 1 30 pS/cm. The meta-emulsion is then concentrated to obtain a composition based on the lipid globules having an action against the lice as described previously.

EXAMPLE 2:

In this example, we refer to an embodiment of the process which is almost identical to that of example 1 in the course of which two phases are involved:

- A fatty phase made up follows - PEG-30 dipolyhydroxystearate 2 % - PEG-6 stearate and ceteth-20 and steareth-20 6 % - Isohexadecane 6 % - cyclomethicone 3 % Tocopheryl acetate 0.5 % - Butylhydroxytoluene 0.1 % Aqueous phase: disodium EDTA 0.2 % - demineralised water 25 % Active principle: essential oil (HE) - melaleuca - HE matricaria - HE lavender, in a solution in a trailer aside the odd hexanoic acid 7 %. A phase inversion occurs at 71 °C,

- An aqueous phase made up of: - Chlorhexidin digluconate 0.5 % - water 49.7 %.

The process of the invention makes it possible to obtain a meta-emulsion which is easy to use for compositions as a treatment for pediculosis in which the globule size is accurately calibrated and adjusted to the orifices of the parasites, more particularly in the region of 5 to 9 μηη. In addition, the smaller the size of the particles, the greater the physical stability of the composition because of the disappearance of maturation and coalescence phenomena. Accordingly, the composition obtained corresponds more or less to a monodispersed system in which the globules are more or less of the same size.

Globules manufactured with this process also have the advantage of leading to improved distribution and reinforced penetration of the active principles into the breathing system of the lice with respect to the active principle, in particular through the caps of the nits. The composition of the invention allows the efficient penetration of the active principles into the parasites, whatever their stage of development. Accordingly, we obtain a greater concentration of active principles in the breathing passages of the parasites at every stage of development, without the use of a neurotoxin or an insecticide that could be dangerous to man.

This results in the exemplary decreasing of any side effects, while providing physical stability in the end product. It also guarantees efficient eradication of the parasites in one application.

This composition is finally a way of efficiently treating, without a disagreeable odor and without any risk of irritation or side effects or any repetition of the treatment, every stage of human and animal pediculosis.

The present invention also concerns a system for the treatment of human or animal pediculosis including:

- a composition as described previously, - a device for the removal of dead parasites.

The removal device could advantageously consist of a comb to remove dead parasites, for example a fine toothed louse comb capable of detaching, removing and lifting away dead lice and nits from the hair of the user, after the application of the composition.

In a particularly advantageous embodiment, this treatment system is accordingly a way of carrying out the treatment of human pediculosis, preferably a pediculosis and ovacidal treatment kit for man. A system like this guarantees in one application, on the one hand, the death of any lice and nits liable to be in the hair and on the scalp and secondly, the complete elimination of these lice and nits by a simple combing gesture. The present invention also concerns the use of at least one first active principle having filmogenic properties, encapsulated in at least one globule whose size is designed to allow the penetration of said at least one globule into the breathing orifices of at least one parasite and its eggs, in a composition for the treatment of human or animal pediculosis. Preferably, it involves the use of the previously described composition.

Finally, this invention concerns a process for the treatment of pediculosis in man during which a composition is used including at least one first active principle adding filmogenic properties and designed to cover, at least partly, at least one parasite responsible for said pediculosis, in order to prevent the latter from breathing. The process includes a step of penetration of said at least first active principle, which is encapsulated in at least one globule, into the breathing orifices of said at least one parasite and its eggs, size of said globule being designed to allow said penetration into said breathing orifices of said at least one parasite and its eggs.

In a particularly preferable embodiment, the composition conforms with the above and this process represents a pediculicidal and ovacidal treatment for man, through a single application of said composition.

In an advantageous manner, the treatment process includes a stage for the application of said composition to the scalp and/or hair of user.

In the course of this application stage, the user pours the composition initially stored in a conventional container, for instance a plastic bottle, directly onto the hair and scalp. Advantageously, the user can then facilitate the spreading out of the composition, preferably as a lotion, by lightly massaging it into the scalp and hair.

Then, following said application stage, the treatment process includes a rest stage during which said composition is allowed to stand on the scalp and/or hair of the user so that said composition enters into the breathing orifices of at least one parasite and the eggs of the latter to form a film around them, in particular by the evaporation of at least part of said composition. In fact, during the rest stage, the composition tends to dry out by the evaporation of at least one part of the hydrosoluble components which, combined with the nature of the other components of the composition, modifies the physical phase of the composition which evolves toward the a filmogenic structure which is substantially hermetic and sealed to all fluid.

The treatment process also includes, preferably, following the rest stage, a washing stage in the course of which the composition on the scalp and/or in the hair of the user is eliminated, at least partially. In practice, the user simply rinses his hair and scalp and may, if he or she wishes, use a conventional shampoo to complete the washing process.

After the washing stage, the treatment process of the invention advantageously includes a combing stage in the course of which the hair is combed to remove any dead parasites. Preferentially, this combing stage is carried out using a device for the removal of lice and nits, for instance a fine-toothed louse comb. A stage like this advantageously contributes to clearing the hair of any dead parasites not removed by the washing stage.

Following this pediculosis and ovacidal treatment, the user will no longer have any lice or nits, through a single application on the composition. This treatment based on the composition of the invention therefore has the advantage of being particularly efficient, simple and fast to implement. In particular, it is a quick means of treating, without any risk of contagion, a large number of users, in particular schoolchildren, or more generally, treated people in a community.

The composition of this invention is also a way of efficiently treating, without a disagreeable odor and without any risk of irritation or side effects or any repetition of the treatment, every stage of human and animal pediculosis.

SUSCEPTIBILITY OF INDUSTRIAL APPLICATION

The invention could have an industrial application in the definition and manufacturing of compositions for the treatment of pediculosis.

Claims

1 - A composition for the treatment of human or animal pediculosis including at least one first active principle having filmogenic properties and which is designed to cover, at least partially, at least one parasite responsible for said pediculosis, to prevent the latter from breathing, said composition being characterized in that said at least one active principle is encapsulated in at least one globule whose size is designed to allow said globule to penetrate into the breathing orifices of said at least one parasite and its eggs.

2 - A composition for the treatment of pediculosis according to claim 1 , characterized in that each globule presents a size which is smaller than the size of the breathing orifices of the parasite and its eggs, preferably included approximately between 1 and 10 μητι, preferably included approximately between 5 and 9 μηη.

3 - A composition for the treatment of pediculosis according to claim 1 or 2, characterized in that the globule includes at least one more or less water- dispersible wall enclosing said first active principle, which wall is designed to evaporate, at least partially, to allow said first active principle first to come out, in a more or less fluid form, of the inside of the parasite through its pores, and also to solidify as a film around said the parasite and its eggs, to prevent the latter from breathing and cause their death. 4 - A composition for the treatment of pediculosis according to one of claims of 1 to 3 characterized in that the first active principle contains at least one liposoluble compound chosen from the following compounds: vegetable oils, mineral oils, mineral oil substitutes, silicones and triglycerides.

5 - A composition for the treatment of pediculosis according to one of claims 1 to 4 characterized in that it includes at least one second active principle designed to act directly on the parasite and its eggs.

6 - A composition for the treatment of pediculosis according to claim 5 characterized in that the second active principle includes at least one liposoluble essential oil. 7 - A composition for the treatment of pediculosis according to one of claims 1 to 6 characterized in that it is in the form of a fluid design for application to the human and/or animal body.

8 - A composition for the treatment of pediculosis according to one of claims 1 to 7 characterized in that it is designed for monodose pediculicidal or ovacidal treatments, in particular for the treatment of lice on man.

9 - A manufacturing process of a composition for the treatment of human or animal pediculosis including at least one first active principle having filmogenic properties and which is designed to cover, at least partially, at least one parasite responsible for said pediculosis, to prevent the latter from breathing, said manufacturing process being characterized in that it includes a stage of encapsulation of said at least one first active principle in at least one globule whose size is designed to allow said globule to penetrate into the breathing orifices of said at least one parasite and its eggs. 10 -A manufacturing process according to claim 9, characterized in that the encapsulation stage includes a sub stage for the manufacturing of the emulsion during which: a) an aqueous phase and a fatty phase are prepared, b) the temperature of the two phases is increased to a temperature above the phase inversion temperature, c) the two phases are mixed, d) the first liposoluble active principle is added to the liposoluble phase, e) the temperature is reduced to the phase inversion temperature, f) after phase inversion and the obtaining of a continuous aqueous phase emulsion, the emulsion obtained is soaked to bring down its temperature.

1 1 -A manufacturing process according to claim 10, characterized in that it includes a sub stage c') designed to reduce the temperature to a temperature immediately above the phase inversion temperature. 12 - A manufacturing process according to claim 10 or 1 1 characterized in that stage c) is carried out before stage b).

13 - A manufacturing process according to one of claims 10 to 12, characterized in that the emulsion obtained is a meta-emulsion, which is then put through a concentration substage in the course of which the aqueous phase is partly eliminated.

14 -A process according to any of claims 10 to 13, characterized in that during substage c), the first active principle is dissolved in a fatty phase complement before being incorporated into the liposoluble phase. 15 - A process according to any of claims 10 to 14, characterized in that meta-emulsion obtained in the course of substage f) includes globules more or less rounded in shape with size included approximately between 1 and 10 μητι, preferably included approximately between 5 and 9 μηη.

16 -A process according to any of claims 10 to 15, characterized in that the meta- emulsion obtained in the course of substage f) is designed to a monodose pediculicidal and ovacidal treatment, in particular for the treatment of lice in man.

17 - Lotion for the treatment of pediculosis in man or the animal including a composition according to any of claims 1 to 8.

18 - A system for the treatment of human or animal pediculosis including: - a composition according to one of claims 1 to 8,

- a device for the removal of dead parasites.

19 - Use of at least one first active principle having filmogenic properties filmogenic properties, encapsulated in at least one globule whose size is designed to allow the penetration of said at least one of globules into the breathing orifices of at least one parasite and its eggs, in a composition for the treatment of human or animal pediculosis. 20 -A process for the treatment of pediculosis in man in the course of which a composition including at least one first active principle having filmogenic properties and which is designed to cover, at least partially, at least one parasite responsible for said pediculosis, to prevent the latter from breathing, said process being characterized in that it includes a step of penetration of said at least first active principle, which is encapsulated in at least one globule, into the breathing orifices of said at least one parasite and its eggs, size of said globule being designed to allow said penetration into said breathing orifices of said at least one parasite and its eggs. 21 - A process for the treatment of pediculosis according to claim 20, characterized in that it includes a stage for the application of said composition to the scalp and/or hair of user.

22 - A process for the treatment of pediculosis according to claim 21 , characterized in that it includes, following said application stage, a rest stage during which said composition is allowed to stand on the scalp and/or hair of the user so that said composition enters into the breathing orifices of at least one parasite and the eggs of the latter to form a film around them, in particular by the evaporation of at least part of said composition.

23 - A process for the treatment of pediculosis according to claim 22, characterized in that it includes, following the rest stage, a washing stage in the course of which the composition on the scalp and/or in the hair of the user is eliminated, at least partially.

24 - A process for the treatment of pediculosis according to claim 23, characterized in that it includes after the washing stage, a combing stage in the course of which the hair is combed to remove any dead parasites.

25 -A process for the treatment of pediculosis according to any one of claims 20 to 24 characterized in that it represents a pediculicidal and ovacidal treatment process for man, through a single application of said composition.