AU2003100144B4 - Lousicide composition - Google Patents

Description

AUSTRALIA

Patents Act 1990 JUROX PTY LTD COMPLETE SPECIFICATION INNOVATION PATENT Invention Title: Lousicide composition The following statement is a full description of this invention including the best method of performing it known to us:- LOUSICIDE COMPOSITION Technical Field This invention relates to parasiticide compositions, especially liquid compositions for use in the treatment of lice infestations in animals such as sheep.

Background Art Insecticide and parasiticide compositions are widely used in the veterinary field to deliver active substances in liquid form to animals, particularly farm animals. The insecticide/parasiticide compositions may be given to the animal orally (by way of drench) or by application to an external part of the animal, When applied to an external part of the animal the insecticide/parasiticide composition is referred to as a "pour-on composition". The desirability of pour-on compositions stems from ease of use especially when application along with effectiveness is achieved.

The essence of a pour-on composition is that it is formulated as a liquid for topical application to the skin of an animal, such as along the back of the animal.

Desirably, a pour-on composition spreads on the skin so as to deliver effectively the insecticide/parasiticide composition to the animal.

Lice are one form of parasite that frequently infect sheep. Various compositions have been provided specifically as pour-on compositions for use in the treatment of lice infections in sheep.

Triflumuron is an insect growth regulator used to destroy insect larva.

Essentially, triflumuron prevents the formation of new chitin during the insect's malting stage. Chitin is the substance that makes up the insects exoskeleton and triflumuron acts as a chitin synthesis inhibitor by preventing the enzyme necessary to produce chitin from functioning. In particular, triflumuron is an external parasiticide which prevents the development of immature lice present in the fleece of sheep. However, triflumuron is ineffective against mature lice. Having regard to this short coming, it would be desirable to provide a composition that is effective both in killing mature lice as well as preventing the development of immature lice.

Whilst triflumuron may be used in the manner described above, the fact that it is water insoluble results in a number of problems when a parasiticide composition containing triflumuron is applied to an animal via an applicator device. More specifically, an applicator used to apply the composition to the sheep becomes clogged due to crystallisation of the triflumuron from the parasiticide composition. The crystallisation is due to low solubility of triflumuron in water and limited solvation power of the solvent system in the composition. It would be desirable; therefore, to ensure that a parasiticide composition containing triflumuron is not subject to this limitation in use.

Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed in Australia before the priority date of each claim of this application.

Disclosure of Invention The present inventors have now found a means to provide a parasiticide composition that is effective against both immature and mature lice, which is based on triflumuron and is water washable. This has been achieved by including an effective amount of one or more pyrethroids together with specific surfactants and solvents.

Accordingly, in a first aspect, the present invention is directed to a water washable lousicide composition comprising: 0o 01 30% w/v oftriflumuron; 0.01 20% w/v of one or more pyrethroids; 0.005 30% w/v of one or more surfactants; the balance being an organic solvent selected from the group consisting of glycols, glycol ethers, glycol ether acetate, CI-Cs alkyl pyrrolidones, butyrolactone and mixtures thereof In a second aspect, the present invention is directed to a method of treating lice in an animal, the method comprising administering to the animal an effective amount of the lousicide composition according to the first aspect of the invention.

In a third aspect, the present invention is directed to the use of the lousicide composition according to the first aspect of the invention in the preparation of a medicament for the treatment of lice in an animal.

In a fourth aspect, the present invention is directed to a method of cleaning a device containing a residual amount of a water washable lousicide composition according to the first aspect of the invention, the method comprising washing the device with an aqueous solution in a manner so as to effectively remove substantially all of the composition from the device.

Throughout the specification it will be understood that the term "water washable" means that when water is added to the parasiticide composition, triflumuron forms a coarse emulsion which contains fine crystals oftriflumuron.

Triflumuron is included in the composition in the concentration of 0.01-30% w/v. Preferably the concentration used is in the range of 1-10%w/v, most preferably 1w/v, even more preferably about 2.5% w/v. A concentration of about 2.5% w/v of triflumuron in the composition provides a practical dose range for use in treating animals such as sheep. A concentration below 2.5% w/v results in the requirement of a higher dose volume and results in fewer sheep being treated per pack of insecticide or parasiticide composition. A concentration higher than 2.5%w/v results in a crystallisation problem which can only be overcome by using an increased amount of the surfactant.

One or more surfactants is included in the composition. The surfactant may be selected from non-ionic, anionic, cationic or amphoteric surfactants. Preferably, a nonionic surfactant is used. It has surprisingly been found that the addition of a surfactant into the triflumuron containing parasiticide composition reduces the crystal size of the triflumuron during washing with water in such a way that the applicator device will not clog and can be reused again. The surfactant may also function as a spreading agent.

Non-ionic surfactants may be selected from the group consisting of alkylphenol ethoxylates, C9-C17 alcohol ethoxylates, C8-C20 alkyl amine ethoxylates, castor oil ethoxylates, lanolin alcohol ethoxylates, sorbitan fatty acid ester ethoxylates, sorbitan fatty acid esters and mixtures thereof.

The C8-C10 alkylphenol ethoxylates preferably contain from 2 to 100 moles of ethylene oxide and may be selected from but not limited to the commercially available products identified as Teric N9, Teric N20 and Teric N100. The C9-C17 alcohol ethoxylates preferably contain from 2 to 25 moles of ethylene oxide and may be selected from but not limited to the commercially available products identified as Teric 9A2 and Teric 16A16. The C8-C20 alkyl amine ethoxylates preferably contain from to 20 moles of ethylene oxide and may be selected from but not limited to the commercially available products identified as Teric 13M15 and Teric 18M20. The castor oil ethoxylates preferably contain from 5 to 60 moles of ethylene oxide and may be selected from but not limited to the commercially available products identified as Cremophor EL, Acconon CA-5 and Teric 380. The lanolin alcohol ethoxylates preferably contain from 5 to 40 moles of ethylene oxide and may be selected form but not limited to the commercially available products identified as Polycol 5 and Polycol The sorbitan fatty acid ester ethoxylates preferably contain 4 to 20 moles of ethylene oxide and may be selected from but not limited to Polysorbate 20, Polysorbate 60 and Polysorbate 80. The sorbitan fatty acid esters preferably have a chain length of C18-C60 and more preferably have an HLB of 2-9 and may be selected from but not limited to sorbitan monoisostearate, sorbitan monostearate, Hodag SML and Span The non-ionic surfactant spreading agent is in a concentration of 0.005 30% w/v.

Preferably, the concentration used is in the range of 0.01-20% most preferably 0.1-15% w/v.

The availability of surfactants is shown in Table 1.

A variety of pyrethroids, particularly synthetic pyrethroids may be used. These include the following: alpha cypermethrin, deltamethrin, cypermethrin, lambda cyhalothrin, permethrin and flumethrin. Typically, these pyrethroids will be used in a concentration of 0.01-20% w/v, preferably 0.1-10% w/v, most preferably 0,5-5.0% w/v.

Especially preferred is a concentration of about 1.2% w/v.

An organic solvent selected from the group consisting of glycols, glycol ethers, glycol ether acetate, CI-Cs alkyl pyrrolidones, butyrolactone and mixtures thereof is included in the composition of the invention. The organic solvent forms the balance of the composition. The concentration of the solvent may be in the range of 10-99.985% w/v. Preferably, the concentration used is in the range of 20-99.5% most preferably 99.5% w/v. A preferred solvent is a mixture of dipropyleneglycol monomethyl ether and N-methyl pyirolidone.

The composition may further include additives which are commonly used in insecticide/parasiticide compositions including but not limited to dyes and oils such as hydrocarbon oils, mineral oils, vegetable oils and mixtures thereof To produce the compositions of the invention, the triflumuron and pyrethroid is dissolved in the organic solvent and the surfactant is added to the solution and mixed until homogenous.

The composition according to the present invention may be used as a pour-on preparation or as a drench. Preferably, the composition is used as a pour-on preparation. The composition is preferably applied along the back of the animal using an applicator device, such as a gun.

Whilst compositions made according to the invention will find the greatest application in sheep, they are also useful in treating cattle, deer, buffalo and goats.

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

Modes for Carrying out the Invention In order to better understand the nature of this invention, a number of examples will now be described.

Example 1 Ingredient Amount (g/L) Triflumuron Alpha cypermethrin 12 Dipropyleneglycol monoethyl ether to I L N-methylpyrrolidone 290 Teric 380 Example 2 Ingredient Amount (g/L) Triflumuron Cypermethrin N-methylpyrrolidone to IL Teric N9 Example 3 !Ingredient Amount (g/L) Triflumuron Deltamethrin Polysorbate 80 100 N-methylpyrrolidone to IL In Examples 1-3, each composition was prepared by dissolving the triflumuron and the pyrethroid in N-methylpyrrolidone and, in the case of Example 1, dipropyleneglycol monoethyl ether, followed by the addition of the surfactant, Teric 380, Teric N9 or Polysorbate 80. The availability of all of the ingredients used is set out in Tables 1 and 2.

Table 1 Ingredient Availability Ingredient Available from Triflumuron Jurox Dipropyleneglycol monomethyl ether ICI N-methyl pyrrolidone APS Teric N9, Teric N20, Teric N100, Teric 9A2, Teric 16A16, Teric 13M15, Teric 18M20 and Teric 380 ICI Cremophor EL BASF Corporation Acconon CA-5 Karlshamns USA Inc Polycol 5 and Polycol 40 CRODA Polysorbate 20 (trade name Tween 20), Polysorbate (trade name Tween 60) and Polysorbate 80 (trade name Tween 80) ICI Hodag SML Calgene Span 25. ICI Table 2 Pyrethroid Ingredient Availability lngredient Available from Flumethrin Jurox Alpha cypermethrin Isagro Deltamethrin Tung Han Cypermethrin PRI Lambda cyhalothrin PRI Permethrin PRI Note that all of the pyrethroids used were technical grade having a minimum active content of 98% w/w.

8 It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention.as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (5)

1. A water washable lousicide composition comprising: 0.01 30% w/v of triflumuron; 0.01 20% w/v of one or more pyrethroids; 0.005 30% w/v of one or more surfactants; and the balance being an organic solvent selected from the group consisting of glycols, glycol ethers, glycol ether acetate, C 1 -Cs alkyl pyrrolidones, butyrolactone and mixtures thereof

2. The water washable lousicide composition according to claim 1 wherein the surfactant is a non-ionic surfactant selected from the group consisting of C8-C10 alkylphenol ethoxylates, C9-C17 alcohol ethoxylates, C8-C20 alkyl amine ethoxylates, castor oil ethoxylates, lanolin alcohol ethoxylates, sorbitan fatty acid ester ethoxylates, sorbitan fatty acid esters and mixtures thereof

3. The water washable lousicide composition according to claim 1 or 2 wherein the organic solvent is N-methyl pyrrolidone or a mixture of dipropyleneglycol monoethyl ether and N-methyl pyrrolidone.

4. The water washable lousicide composition according to any one of claims 1 3 wherein the triflumuron is in a concentration of 1-10% w/v, the one or more pyrethroids are in concentration 0.1 10% w/v and the surfactant is in a concentration of 0.01-20 w/v.

5. A water washable lousicide composition comprising: 5.0% w/v oftriflumuron; 5.0% w/v of a synthetic pyrethroid selected from the group consisting of alpha cypermethrin, deltamethrin, cypermethrin, lambda cyhalothrin, permethrin and flumethrin; 0.1 15% w/v of one or more of surfactants selected from the group consisting of castor oil ethoxylates, lanolin alcohol ethoxylates, sorbitan fatty acid ester ethoxylates containing from 4 to 20 moles of ethylene oxide and C8-C 10 alkylphenol ethoxylates containing from 2 to 100 moles of ethylene oxide; and the balance being N-methyl pyrrolidone or a mixture of N-methyl pyrrolidone and dipropyleneglycol monoethyl ether. Dated this 4th day of March 2003 Jurox Pty Ltd Patent Attorneys for the Applicant: F B RICE CO