NZ248486A

NZ248486A - Stable anthelmintic formulation containing closantel and one or more avermectins or milbemycins in a glycol based solvent

Info

Publication number: NZ248486A
Application number: NZ248486A
Authority: NZ
Inventors: Colin Manson Harvey
Original assignee: Ashmont Holdings Limited Subst
Priority date: 1993-08-24
Filing date: 1993-08-24
Publication date: 1996-07-26
Also published as: WO1995005812A1; EP0724437A1; EP0724437A4; AU7469494A; ZA946195B; AU695582B2

Description

New Zealand Paient Spedficaiion for Paient Number £48486 • 24 8 4 8 6 Patents Form #5 ; I.

C' NEW ERALANP . ■*" ^ ■\ iS AUG W94n\; Patents Act 1953 A / COMPT.ETF SPECIFICATION ^ TITLE: Anthelmintic Formulations Ashmont Holdings Limited, a New Zealand company, of 48 Diana Drive, d, Auckland, New Zealand hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: PF05.JWP FEE CODE - 1050 24 8 48 6 ABSTRACT OF THE DISCLOSURE This invention relates to anthelmintic compositions and has particular application to injectable compositions containing closantel together with an avermectin or milbemycin such as moxidectin, ivermectin, doramectin Milbemycin D, or other milbemycins together with a glycol based solvent such as polyethylene glycol or propylene glycol. The formulations may also include trace elements and/or vitamins.

FIELD yj This invention relates to veterinary compositions for the treatment of helminthiasis in warm-blooded animals, more particularly cattle, sheep, goats, and other domesticated herbivores.

BACKGROUND Helminthiasis is a widely occurring disease in farmed animals. It commonly causes clinical disease and has significant adverse economic effects on farming economies when present at subclinical levels. Over the past twenty-five years a number of initially successful anthelmintic agents, with relatively specific effects on the metabolism of smaller or larger groups of endoparasites have been discovered, trialled, and used 25 successfully to control helminthiasis on farms. Various groups of compounds have a greater or lesser spectrum of activity - that is to say they are able to destroy a wider or smaller range of parasite. For example, the widely used "ivermectin" is active against parasitic roundworms and also against some ectoparasites, yet it is inactive against tapeworms because of a difference in their biochemical constitution. "Triclabendazole" is active only against the liver fluke Fasciola hepatica.

The drug closantel is a useful anthelmintic active agent that gives control over a range of internal parasites including liverfluke in cattle and sheep. For this reason it has been used in aqueous suspension in combination with other anthelmintics such as albendazole and mebendazole.

This invention is based on the surprising discovery that an anthelmintic soli^n-can^^e v Vk 6006JCS3.596/JP/wp jt jt li 9 7 BJIflU inn. m ! 2 4 8 4 8 8 prepared from a combination of closantel and an avermectin or milbemycin like anthelmintic, for example ivermectin, moxidectin and doramectin. Such solutions have advantages in ease of use and may also be used by injection. Glycol based solvents ^ such as polyethylene glycol and propylene glycol are able to dissolve both compounds to produce a stable formulation. Such formulations may also be dispersed in water.

The milbemycins are described in the 11th Edition of the Merck index as a family of novel macrolide antibiotics with Milbemycin D in particular being used as an anthelmintic. The avermectins are described in the 11th Edition of the Merck index as J0 a group of broad-spectrum antiparasitic compounds which are derivatives of pentacyclic 16-membered lactones related to the milbemycins. The most well known of these avermectins is ivermectin which is a semi-synthetic derivative of abamectin (one of the avermectins). /5 OBJECT It is an object of this invention to provide novel veterinary compositions having anthelmintic activity.

STATEMENT OF INVENTION In one aspect the invention comprises a stable anthelmintic formulation comprising a glycol based solvent together with an effective amount of closantel and an effective amount of one or more anthelmintics chosen from the group consisting of ine class of avermectins and the class of milbemycins.

In a further aspect the invention provides a method for treating helminthiasis in animals with compositions comprising an effective amount of the anthelmintic closantel together with a glycol based solvent and an effective amount of at least one other anthelmintic.

Preferably the other anthelmintic is chosen from the group comprising the avermectins or milbemycins. Such a group includes moxidectin, ivermectin, doramectin, Milbemycin D, as well as other milbemycins.

Preferably the glycol based solvent consists of a mixture selected from at least two of: 2 4 8 4 8 6 Preferably the compositions of the present invention are used by injection. They may also include trace elements and/or vitamins.

Preferably the closantel and other anthelmintic may be each present at from 0.5 to 15% w/v respectively, and more preferably the closantel is present at from 1 to 2% w/v.

In another aspect the invention provides a method of treating animals for helminthiasis by injecting a composition as previously described at the rate of lmL/50kg of the animal's live weight (different dose rates and percentages of active ingredients will 10 become apparent from the examples).

EXAMPLES These and other aspects of the invention will be apparent from the following yj description, which is given by way of example only.

Example 1: % w/v Closantel 3.75 Ivermectin 0.08 Propylene glycol to 100.00 Polyethylene glycol 20.00 This formulation is suitable for use as an oral drench for sheep which would offer control of parasites resistant to older anthelmintics such as the benzimidazoles and 25 levamisole as well as controlling adult liverfluke.

Example 2; % w/v Closantel 3.75 Moxidectin 0.10 Propylene glycol 40.00 Polyethylene glycol 20.00 Water to 100.00 This formulation is suitable for use as an injection for sheep and cattle. It gives the 35 advantage of longer action of moxidectin combined with activity against liv^^^^^^1' /f [I* v* 27 MAY 1996 1 6006JCS3.596/JP/wp \ // o/s . V. r> c 2 4 8 4 8 6 Examole 3: % w/v Abamectin (88.8%) 1.13 Sodium Closantel 1.30 Glycerol formal (i) 40.00 Water 30.00 Sodium Selenate 1.20 Tween 80 20.00 Benzyl Alcohol 1.00 Glycerol formal (ii) to 100.00 This is an injectable composition containing selenium.

Preparation Example To a clean dry mixing vessel, add the glycerol formal (i) and Tween 80. With stirring, add the abamectin and sodium closantel, and heat to about 60° - 70° C with continued stirring until dissolved. Dissolve the sodium selenate in water and add to the batch while stirring. Allow to cool to room temperature and add the benzyl alcohol, stirring well to disperse. Make up to 100% volume with glycerol formal (ii).

Trial solutions of Exampie 3 were found to be stable overnight at 2°C, 21°C and 37°C with the active ingredients remaining soluble at all temperatures.

Use This injectable formulation can be applied to cattle at a dose rate of lmL/50kg of live 25 weight, to provide the anim?l with 2.5mg/kg of closantel whilst at the same time supplying an effective dose of abamectin and a trace element such as selenium.

Example 4; Dose rate lml/50kg g/L Abamectin Closantel 125 Glycerol formal 400 PEG 400 600 Benzyl alcohol 6006JCS3.596/JP/wp 2 4 8 4 8 6 This provides another injectable formulation without the trace element by using a combination of polyethylene glycol (PEG 400) and glycerol formal.

Examples 5-7 show other injectable compositions containing different amounts of closantel to be used at a formulation dose rate of 1 mL/25kg of animal live weight.

Example 5: Dose rate lml/25kg g/L Abamectin Closantel 187.5 Glycerol formal 400 PEG 400 600 Benzyl alcohol Example 6: Dose rate lml/25kg g/L Abamectin Closantel 62.5 Glycerol formal 400 PEG 400 600 Benzyl alcohol Example 7: Dose rate lml/25kg g/L Abamectin Closantel 125 Glycerol formal 400 PEG 400 600 Benzyl alcohol * °X V i — nv t 27 MAY 7396 * - tV 6006JCS3.596/JP/wp ..J

Claims

2 4 8 4 8 6 -7- VARIATIONS In addition to the combination of closantel and an avermectin or milbemycin the j compositions of this invention can contain trace elements. Example 3 describes a composition containing selenium. Other trace elements or vitamins may be included. Examples of trace elements include copper, cobalt, iodine, zinc or the like. The vitamins may be for example vitamins A, B, D, or E. ADVANTAGES 10 The compositions of this invention are stable and safe to use. The glycol based solvents used in this invention are non-irritant solvents and can safely be used in injectable compositions. The injectable compositions are particularly suited to the control of helminthiasis in cattle. 20 25 24 8 48 6 -8- WHAT Wfi CLAIM IS:

1. A stable anthelmintic formulation comprising a glycol based solvent together j with an effective amount of closantel and an effective amount of one or more anthelmintics chosen from the group consisting of the class of avermectins and the class of milbemycins.

2. A stable anthelmintic formulation as claimed in claim 1, wherein the avermectins and the milbemycins are selected from the group consisting of abamectin, 10 ivermectin, moxidectin, doramectin and Milbemycin D.

3. A stable anthelmintic formulation as claimed in any one of claims 1-2 wherein the glycol based solvent consists of a mixture selected from at least two of: (a) propylene glycol, (b) polyethylene glycol, (c) glycerol formal, and (d) water. 15

4. A stable anthelmintic formulation as claimed in claim 3, wherein the closantel and other anthelmintic are each present at from 0.5% to 15% w/v respectively.

5. A stable anthelmintic formulation as claimed in claim 1 substantially as herein described with reference to the examples.

6. A process for the preparation of a stable anthelmintic formulation as claimed in claim 1 substantially as herein described with reference to the examples.

7. An injectable formulation comprising a stable anthelmintic formulation as 25 claimed in any one of claims 1-6.

8. A method for treating helminthiasis in animals (other than humans) by injecting a stable formulation as claimed in claim 7 at the rate of lmL/25kg to lmL/50kg of the animal's live weight. 20 30 35 Ashmont Holdings Limited By its Attorneys James W Piper & Co \ 27 MAY 1996 l! e 1 . 6006JCS3.596/JP/wp