Method for controlling ectoparasites

Abstract: A method for controlling ectoparasites systemically through host animal blood which comprises applying at least one selected from the neonocotinoid compounds defined in the specification to the host animal.

Description: The present invention relates to a compound for systemic control of ectoparasites and its use in the preparation of a medicament for the same purpose. It is known that a regional application of a sort of compounds to animals can prevent the animals from infection of ectoparasites in AU-B-20144/95. However, such an application, which is for controlling ectoparasites non-systemically, was not always sufficient in quick-acting effect or residual effect, for example, an effective action is delayed on the part except applied directly, especially far from the part applied directly, and an effect is lowered or unstable owing to bathing or washing of hair or body surface. WO 93/24002 discloses 1-[N-(Halo-3-pyridylmethyl)]-N-methylamino-1-alkylamino -2-nitroethylene derivatives for systemic control of fleas on pets. The present invention provides 1-(tetrahydrofuran-3-yl) methyl-3-methyl-2-nitroguanidine for systemic control of ectoparasites and its use in the preparation of a medicament for this purpose. The present invention allows an effective ectoparasite controlling method, that is a method for controlling ectoparasites systemically, through blood of a host animal which is characterized by applying 1-(tetrahydrofuran-3-yl)methyl-3-methyl-2-nitroguanidine. In the present invention, the word "systemic control" means that the applied agent moves into blood of a host animal, the concentration of the agent in the blood is kept at a certain level and ectoparasites are controlled all over the body through the blood of the host animal. In the controlling method of the present invention, the present compound is applied to a host animal usually at a dosage of 0.01 to 1000mg, preferably 0.1 to 100mg per 1kg of the animal weight. The administration to the host animal is a method for the present compound to enter into animal blood, for example, oral or non-oral administrations, implantation and so on. Examples of the oral administration include a method for applying feed mixed with the present compound to host animal and a method for applying a suitable formulation to animal wherein the formulation is easy to swallow for the animal such as biscuit, wafer, tablet, liquid and capsule. Suitable carriers for these formulations include sugars such as lactose, sucrose, mannitol, sorbitol, cellulose and cellulose derivatives; excipients such as calcium phosphate; binders such as starch paste (utilized with corn, wheat, rice or potato starch), gelatin, tragacanth, methylcellulose, agar, alginic acid and alginic salts; lubricant such as silica, talc, stearic acid and stearic salt; and formulation cores that are sugar solution containing gum arabic, talc, polyvinylpyrrolidone or titanium dioxide. The formulations may optionally comprise coloring agent or seasoning. Further examples of the formulations for oral administration include dry capsules encapsulated a mixture of the present compound, excipients such as lactose, binder such as starch, lubricant such as talc and magnesium stearate and stabilizer in dry capsules of gelatin, and sealed soft capsules encapsulated the present compound dissolved or suspended in a suitable liquid such as fatty oil and paraffin oil or a mixture of the solution or suspension with a stabilizer in soft capsules comprising gelatin and plasticizer (e.g. glycerin, sorbitol). Non-oral administration is usually an injection administration. Examples of the non-oral administration include an endermism with a percutaneous absorptive formulation, a hypodermoclysis utilized with a hypodermic injection formulation, an intramuscular administration utilized with a intramuscular injection formulation and an intravenous administration utilized with an intravenous injection formulation. For these administrations, a liquid formulation such as solution, suspension and emulsion of the present compound is utilized. The liquid formulation includes aqueous solvents such as water, physiological saline and Ringer's solution; or lipophilic solvents such as fatty oil, sesame oil, corn oil and synthetic fatty acid ester. The aqueous solution containing the aqueous solvent is usually prepared from a water-soluble salt of the present compound. A method for implanting a formulation of resin spread or molded the present compound to a host animal may be utilized. In the controlling method of the present invention, other insecticidal ingredient may be utilized together with the present compound. Examples of other insecticidal ingredients include insect growth regulating substances such as methoprene, hydroprene, lufenuron, chlorfluazuron, flufenoxuron, hexaflumuron, diflubenzuron, 1-(2,6-difluorobenzoyl)-3-[2-fluoro-4-(1, 1, 2, 3, 3, 3-hexafluoropropoxy)phenyl]urea, cyromazine and tebfenozide; insecticidal substances such as N-phenylpyrazoles; and endoparasite-controlling substances such as milbemycin, abamectin and avermectin. Examples of the ectoparasites controlled by the present invention include Diptera such as Musca hervei, Musca bezzii, Haematobia irritans, Simulium iwatens, Culicoides oxystoma, Tabanus chrysurus, Culex pipiens (common mosquito) and Aedes albopictus ; Anoplura (lice) such as Haematopinus eurysternus and Damalinia ovis ; and Siphonaptera (fleas) such as Ctenocephalides felis (cat flea), Ctenocephalides canis (dog flea) and Xenopsylla cheopis. The host animals include farm animals and pets. Examples of the farm animals include cattle and sheep, and examples of the pets include Rodentia such as mice, rats, hamsters and squirrels; Lagomorpha such as rabbits; Carnivora such as dogs, cats and ferrets; and Aves (birds) such as ducks, chickens and doves. Examples Below, the present invention is explained with the examples in detail. Formulation example 1 Thirty milligrams (30mg) of 1-(tetrahydrofuran-3-yl)methyl-3-methyl-2-nitroguanidine, 70g of dextrin, 20g of potato starch, 6g of powder food for animals (CE-2 produced from Oriental Kobo Company), 2g of sesame oil and 2g of water are mixed and kneaded. The obtained powder (1g) is molded and pressed at about 8 tons to afford a tablet. Test example A designated amount of 1-(tetrahydrofuran-3-yl)methyl-3-methyl-2-nitroguanidine (referred as Compound A in table 1) suspended in a 0.05% aqueous solution of methylcellulose was orally administered to a mouse (weight: about 30g) with a sonde at a dosage of 10mL per 1kg of weight. The mouse was hold and fixed with wire net and put in a glass container of 900mL volume. Twenty adult cat fleas (unbloodsucked) were deposited. The mortality of adult fleas was examined 24 hours after administration. Each test was repeated thrice. The result is given in table 1. As a comparative test, a corn oil dilution of cyphenothrin (referred as Comparative compound 1 in table 1) was applied to a mouse at a dosage of 25mg/kg, tested in the same manner as above and the mortality of adult fleas was examined 24 hours later. The result is given in table 1. Dosage (mg/kg) Mortality of cat flea (%) Compound A 10.0 65.0 Comparative compound 1 25.0 0.0 Reference example A designated amount of an acetone solution of 1-(tetrahydrofuran-3-yl)methyl-3-methyl-2-nitroguanidine (referred as Compound A in table 2) was applied onto a filter paper. Twenty adult cat fleas were forced to contact with the filter paper and the mortality was examined 24 hours later. Each test was repeated thrice. The result is given in table 2. Further, cat fleas were forced to contact with the filter paper treated with cyphenothrin (referred as Comparative compound 1 in table 2) as a reference and the mortality was examined 24 hours later. Each test was repeated thrice. The result is given in table 2. Dosage (mg/kg) Mortality of cat flea (%) Compound A 160 24 Comparative compound 1 100 88 As shown in the test example and reference example, Compound A is effective for systemic-controlling of fleas though Compound A is not so suitable for controlling fleas at direct contact.

Claims: A veterinary composition, comprising 1-(tetrahydrofuran-3-yl)methyl-3-methyl-2-nitroguanidine as an active ingredient for systemically controlling ectoparasites in a host animal. Use of the neonicotinoid compound 1-(tetrahydrofuran-3-yl)methyl-3-methyl-2-nitroguanidine for the manufacture of a medicament for systemically controlling ectoparasites in a host animal. Use according to claim 2, wherein systemic control is achieved by oral administration, injection administration or implantation. Use according to claim 2 or 3, wherein the dosage of the neonicotinoid compound is 0.1 to 100mg per 1kg of a host animal weight. Use according to claim 2 or 3, wherein the application method of the neonicotinoid compound is an oral administration. Use according to claim 2 or 3, wherein the application method of the neonicotinoid compound is an injection administration. Use according to claim 2 or 3, wherein the application method of the neonicotinoid compound is an implantation. Use according to claim 2, wherein the ectoparasites are controlled through the blood of the last animal.

Inventors: SEMBO SATOSHI, SEMBO, SATOSHI
Applicants: SUMITOMO CHEMICAL CO, SUMITOMO CHEMICAL COMPANY, LIMITED
Application year: 1999
Main classification: A61K31
IPC codes: C07D307, A61K31