AU2012323775B2 - Meloxicam based formulations for providing analgesia in sheep - Google Patents

Abstract

The present invention provides a method of using meloxicam to provide analgesia or control inflammation in sheep wherein the method comprises administering the sheep a therapeutically effective amount of a formulation containing pharmacologically acceptable meloxicam or meloxicam salt. More preferably the method involves administering it to sheep undergoing a painful surgical procedure including one or more of: (i) tail docking, (ii) castration, (iii) muiesing. The formulations provided are adapted for administration via the oral and buccal route and preferably administered to the sheep is in the range of 0.25mg/kg to 1.Omg/kg of bodyweight of the sheep. The formulations provided have a concentration of meloxicam or meloxicam salt between 0.25% and 1 % (w/v) which when administered, result in a C

Description

WO 2013/053015 PCT/AU2012/001240 1 MELOXICAM BASED FORMULATIONS FOR PROVIDING ANALGESIA IN SHEEP TECHNICAL FIELD The present invention relates to formulations for providing potent, 5 prolonged analgesia to livestock undergoing surgery or surgical husbandry procedures. More particularly the invention relates to formulations for providing prolonged analgesia to sheep during and after invasive surgical husbandry procedures such as castration, tail docking and mulesing. BACKGROUND ART 10 There are significant animal welfare issues associated with animal husbandry procedures performed on livestock (primarily, but not limited to cattle, sheep, pigs, deer) without analgesia. Pain mediation in livestock during and after surgery or surgical husbandry procedures is also desirable to reduce stress and subsequent loss of weight and condition, normally associated with 15 an animal subjected to chronic pain during the recovery period without analgesia. Mulesing is a husbandry procedure performed to reduce the incidence of flystrike in merino sheep. It is usually performed in lambs at the time of marking (at 4 to 12 weeks of age) and involves the surgical removal of strips of wool 20 bearing wrinkled skin from around the breech of a sheep. It remains the most effective and practical way of eliminating the risk of breech flystrike in sheep, a condition that can cause a slow painful death in affected animals. Mulesing is often performed without pain relief, or with the application of the topical local anaesthetic solution. 25 Castration of male lambs, and tail docking of all lambs are painful husbandry procedures that are conducted by a majority of sheep meat and wool producers in Australia and other parts of the world. Common techniques include knife and ring castration Studies have shown that behavioural changes indicative of pain last for 30 up to 24 hours with discomfort evident for up to 48 hours. Field-based surgical husbandry procedures, specifically the practice of mulesing has come under considerable public scrutiny in recent years with WO 2013/053015 PCT/AU2012/001240 2 claims that the production of merino wool comes at an unacceptable welfare cost due to the pain caused to the sheep. This has increased pressure for the development of adequate, cost effective and easy to administer pain relief that can be provided at the time of mulesing. However there has not been any 5 effective formulations available to actually improve the welfare of sheep and accordingly there still exists a great demand for such a product. The desirable solution is a cost-effective, efficient, once-only administration of an analgesic agent that provides rapid onset of analgesia for surgical procedures, and thereafter extended analgesia for chronic pain relief. 10 Non-steroidal anti-inflammatory agents (NSAIDs), comprising several classes, are an important component of the veterinarian's armamentarium for analgesia in many species, livestock and companion animals alike. Traditional NSAIDs used in veterinary practice achieve a reduction in inflammatory response by non-selective inhibition of cyclooxygenase (COX). Cyclo 15 oxygenase is the principle enzyme catalysing the arachadonic pathway in order to produce prostanoids. Prostanoids are a subclass of eicosanoids consisting of the prostaglandins (mediators of inflammatory and anaphylactic reactions), the thromboxanes (mediators of vasoconstriction) and the prostacyclins (active in the resolution phase of inflammation). The prostanoids are extremely potent 20 mediators of a diverse group of physiological processes. There are two main isoforms of cyclo-oxygenase, COX-1 and COX-2. COX-2 is induced by inflammatory stimuli in pathophysiological conditions. The most important adverse effects of inhibition of the COX-1 isoenzyme may be evident in the gastrointestinal tract (specifically, gastric ulceration and right 25 dorsal colitis) and the kidneys (specifically, renal papillary damage). NSAIDs that selectively inhibit COX-2 rather than the COX-1 isoenzyme, thereby minimising the impact on the homeostatic effect of prostanoids preferentially synthesised by COX-1, are desirable. Meloxicam is of the enolic acid group of NSAIDs. demonstrated to have superior COX-2 preferential inhibition when 30 compared to other commonly used NSAIDs. Many NSAIDS can and have been used effectively on livestock, but differences in pharmacokinetic and pharmacodynamic parameters between WO 2013/053015 PCT/AU2012/001240 3 species, classes of NSAIDs and even agents within each class may contribute to variances in pharmacology, onset and likelihood of pain mediation from the point of surgery extending for any particular period. To date the absorption, distribution, metabolism and elimination of meloxicam has not been described 5 with respect to sheep, including investigations of the administration of meloxicam to sheep via the oral and buccal routes of administration. It was therefore, unknown whether meloxicam would be effective for use in painful surgical procedures in sheep or whether it had any analgesic or anti inflammatory effect. 10 The object was therefore to investigate the use of novel meloxicam formulations, particularly those specifically adapted for buccal administration, for their effectiveness in the treatment and amelioration of some of the pain and inflammation suffered by sheep, including mulesing, docking and castration. DISCLOSURE OF INVENTION 15 In a first aspect of the invention there is provided a method of using meloxicam to provide analgesia or control inflammation in sheep wherein the method comprises administering the sheep a therapeutically effective amount of a formulation containing pharmacologically acceptable meloxicam or meloxicam salt. More preferably the method involves administering it to sheep 20 undergoing a painful surgical procedure. Still more preferably, the painful surgical procedure comprise one or more of: (i) tail docking (ii) castration 25 (iii) mulesing The method further includes the step of administering the formulation via the buccal or oral route. Preferably the dose administered to the sheep is in the range of 0.25mg/kg to 1.0mg/kg of bodyweight of the sheep. More preferably the dose 30 administered to the sheep is in the range of 0.5mg/kg to 1.0mg/kg of bodyweight of the sheep, most preferably, the dose administered to the sheep is 1.0mg/kg of bodyweight of the sheep.

4 Preferably, the method further includes administering the formulation wherein the concentration of meloxicam or meloxicam salt in the formulation is between 0.25% and 1% (w/v). More preferably, the formulation is in the form of a liquid suspension of 5 meloxicam where the meloxicam is present, at least partially, in the solid phase, and the formulation is administered to the sheep via the oral route. Still more preferably, such a formulation contains one or more of viscosity modifiers, suspending agents, buffers, pH modifying agents, sweeteners, preservatives and solubilisers. Even more preferably, such a formulation additionally 10 comprises glycerol, xylitol, sodium benzoate, citric acid, sodium dihydrogen phosphate, sodium saccharin, xanthan gum, sorbitol and water. Alternatively, the formulation can be provided in the form of a liquid gel containing dissolved meloxicam or meloxicam salt, and the formulation is administered via the buccal route. In such a formulation it is preferable the 15 formulation contains dissolved meloxicam salt. More preferably, the meloxicam salt is the salt of meloxicam and an inorganic or organic base. Still more preferably, the inorganic or organic base is taken from any of: meglumine, monoethanolamine and lysine. The liquid gel formulation is preferably made wherein the inorganic or organic base is taken from any of: meglumine and 20 monoethanolamine. Preferably, the liquid gel formulation additionally includes any of the following: solubilisers, preservatives, thickeners, gelling agents, pH modifying agents and buffers. More preferably, the liquid gel formulation includes propylene glycol, benzyl alcohol and hyd roxyethylcellulose. Alternatively, the liquid gel formulation additionally includes propylene glycol, 25 methyl hydroxybenzoate, propyl hydroxybenzoate and hydroxypropylmethylcellulose. Further in the alternative, the liquid gel formulation additionally comprises ethanol and hydroxyethylcellulose. 04/04/16 4a Alternatively, the formulation is in the form of a liquid solution containing dissolved meloxicam or meloxicam salt and the formulation is administered to the sheep via the oral route. Preferably, such formulation comprises an aqueous solution of a meloxicarn meglumine salt and ethanol. 5 Preferably, the administration of the formulation results in a Cmax plasma concentration in the subject sheep of at least 750ng/ml. Still more preferably, 04/04/16 WO 2013/053015 PCT/AU2012/001240 5 the formulation results in a Cmax plasma concentration in the subject sheep of at least 1000ng/ml. Even more preferably the the administration of the formulation results in a Cmax plasma concentration in the subject sheep of at least 1500ng/ml. 5 Ina further aspect of the invention there is provided the use of a formulation containing a therapeutic quantity of a pharmacologically acceptable meloxicam or meloxicam salt in the manufacture of a medicament for providing analgesia or reduce inflammation in sheep. Preferably the use comprises providing a formulation wherein the 10 concentration of meloxicam or meloxicam salt is between 0.25% and 1 % (w/v). More preferably the formulation is in the form of a liquid gel adapted for administration by the buccal route. Alternatively, the formulation is in the form of a liquid suspension or a solution adapted for administration by the oral route. 15 In a further aspect of the invention, there is provided a kit comprising any of the formulations of claims 26 to 29 wherein the kit comprises a first package containing multiple doses of the formulation and a delivery device that is adapted to co-operate with the package and deliver the product into the mouth of the sheep. 20 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 Meloxicam plasma concentration vs time for 0.5mg meloxicam/kg bw dose administered via IM, IV and Oral routes in sheep (Example 8). Fig. 2 Closer view of Fig. 1. Fig. 3 Meloxicam plasma concentration vs time for 0.5mg meloxicam/kg 25 bw dose administered via Oral routes in sheep (Example 9). Fig. 4 Average Pain Observation Scores v Time (Example 10) Fig. 5 Graph showing the meloxicam plasma concentrations for each treatment group (Example 12) Fig. 6 Graph showing the average meloxicam plasma concentrations for 30 each administration route (Example 12) WO 2013/053015 PCT/AU2012/001240 6 MODES FOR CARRYING OUT THE INVENTION The present invention provides novel meloxicam formulations/routes of administration that for the first time allow meloxicam to be evaluated and surprisingly it has been found to be effective. In particular the invention 5 provides a number of formulations that can be delivered via the buccal route that provide relief from pain and reduction in inflammation in the subject sheep. The advantages of the buccal route of administration include: - Dose accuracy, volume can be adjusted according to weight to achieve best dose accuracy 10 - Ease of application - dose does not have to be swallowed and can be conveniently applied in a typical farm setting - Rapid absorption - avoids the first pass effect associated with gastrointestinal tract absorption - Non-sterile - suited for repeat administration without jeopardizing 15 product integrity compared to injectables - Can be administered by non-professionals who tend to carry out the bulk preparative activities. Many of these advantages are also shared by administration via the oral route including the lack of sterility and the lack of any need to have a licensed 20 veterinarian perform the administration. The formulations of the present invention can be provided in a variety of forms and/or kits including multi dosage forms and single dosage forms. Single dosage forms include preloaded single use syringes and paste dispensers. It is preferable, however, that the formulations be provided in multi dose packs that 25 allow multiple administrations from the one pack. The form that such dosage forms might take include 1. Multi-dose bottles (including containers formed as backpacks or containers adapted for strapping to the arm) that are adapted to feed metered drench guns or similar dispensers by way of a tube, or 30 which are adapted to be mounted on such dispensers directly, or which are adapted to receive reusable syringes for drawing out a single dose for administration; WO 2013/053015 PCT/AU2012/001240 7 2. Multi dose syringes fitted with a calibrated and threaded plunger rod and rotating dial ring that deliver metered doses (Dial-a-Dose T M ) 3. Syringe barrel cartridges that rely on the associated dispenser (similar to a caulking gun) to meter the dose. 5 In many cases, powered delivery systems can be employed to assist in the drawing of the formulation up into the delivery device for administration. In those cases the viscosity of the formulations can be increased as they are not likely to tire an operator of such a powered device unlike manual applications. This allows for a more viscous formulation that is more likely to remain in the 10 mouth of the animal. Small amounts of brilliant blue or other similar dyes can be added without affecting the efficacy of the formulations. These dyes aid the evaluation of whether the formulation has been loaded into the correct area and whether the sheep has managed to expel it from its mouth. What follows are examples of the formulations and methods of 15 administering them in accordance with the invention, though they are not sought to be limiting the scope of the invention. Example 1 - Formulation A - 5mq/mL meloxicam suspension The following constituents are used to make a meloxicam oral 20 suspension of one embodiment of the present invention. Table I Formulation A- 5mg/ml meloxicam suspension Formulation A Ingredient Amount % w/v Meloxicam 0.50% Glycerol 12.0% Xylitol 14.0% Sodium Benzoate 0.10% Citric Acid 0.14% NaH2PO4.2H20 1.54% Sodium Saccharin 0.10% Xanthan Gum 0.50% Sorbitol 18.0% Water qs WO 2013/053015 PCT/AU2012/001240 8 The method of preparing the formulation includes the following steps: a. Charge an appropriate vessel with 500g of water and commence stirring at medium speed. b. To the water add the following in order: Citric Acid, Sodium 5 Benzoate, NaH2PO4.2H20, Sodium saccharin, Xylitol. c. To the above solution add the Xanthan gum, do this slowly while stirring and add directly into the mixing vortex. Continue stirring until evenly dispersed. d. To the bulk solution, add the Glycerol and Sorbitol and continue 10 stirring until the Xanthan gum is fully hydrated. To the bulk solution, introduce while mixing, the Meloxicam. Continue mixing until uniformly dispersed. e. Make the product to volume, mix using high shear until a uniform suspension is obtained. 15 f. The viscosity of the formulation is around 1600cP. Example 2 - Formulation B: 5mq/mL meloxicam liquid gel for buccal/ rectal administration The following constituents are used to make the meloxicam liquid gel of one embodiment of the present invention. 20 Table 2: Formulation B 5mg/mI formulation for oral administration Formulation B Ingredient Amount % w/v Meloxicam 0.50% Meglumine 0.75% Ethanol 15.0% Natrosol HHX (hydroxyethylcellulose) 1.0% Water qs The method of preparing 1 L of the formulation includes the following steps: a. Collect 830g of water in an appropriate vessel and commence stirring. b. To the bulk solution add the Meglumine and mix until dissolved. c. To the bulk solution add the Meloxicam and mix until dissolved. 25 d. To the bulk solution add the Ethanol and mix until uniform.

WO 2013/053015 PCT/AU2012/001240 9 e. To the bulk solution, slowly add the Natrosol HHX. Continue stirring until the Natrosol HHX is fully hydrated and a clear gel is formed. f. Make compounded product to volume and continue stirring until uniform. g. The viscosity of the formulation should be between 1 1,OOOcP and 5 18,OOOcP to prevent the formulation from being swallowed and to maintain it against the cheek of the sheep. Example 3 - Formulation C 2.5mq/mL meloxicam solution for oral administration 10 The following constituents are used to make the meloxicam solution of one embodiment the present invention. Table 3 - Formulation C 2.5mg/mi meloxicam solution Formulation C Ingredient Amount % w/v Meloxicam 0.25% Meglumine 0.75% Ethanol 15.0% Water qs 15 The method of preparing 1 L of the formulation includes the following steps: a. Collect 830g of water in an appropriate vessel and commence stirring. b. To the bulk solution add the Meglumine and mix until dissolved. c. To the bulk solution add the Meloxicam and mix until dissolved. d. To the bulk solution add the Ethanol and mix until uniform. 20 e. Make compounded product to volume and continue stirring until uniform. Example 4 - Formulation D 5mg/mL meloxicam liquid gel for buccal/rectal administration The following constituents are used to make the meloxicam liquid gel of one 25 embodiment of the present invention.

WO 2013/053015 PCT/AU2012/001240 10 Table 4 Formulation D: 5mg/mI meloxicam liquid gel Formulation D Ingredient Amount % w/v Meloxicam 0.5% Propylene glycol 37% Monoethanolamine 0.500% Methyl hydroxybenzoate 0.180% Propyl hydroxybenzoate 0.020% Natrosol HHX 1.000% (hydroxyethylcellulose) Water qs The method of preparing 1L of the formulation includes the following steps: a. In an appropriate vessel collect the Propylene glycol, add to this the Methyl paraben and Propyl paraben. Mix and heat to dissolve (=<60'C). 5 Set aside to cool. b. To the cool paraben solution, add the meloxicam and mix to disperse. c. To the meloxicam dispersion, add the Monoethanolamine and mix until a clear solution is obtained. d. To the bulk solution add 400g of water and mix till uniform 10 e. To the bulk solution add the Natrosol HHX and mix until fully hydrated. f. Make to volume and continue mixing until uniform. g. The viscosity of the formulation should be between 1 1,OOOcP and 18,OOOcP to prevent the formulation from being swallowed and to maintain it against the cheek of the sheep. 15 Example 5 - Formulation E 5mqlmL meloxicam liquid gel for buccal/rectal administration The following constituents are used to make the meloxicam liquid gel of one embodiment of the present invention. 20 WO 2013/053015 PCT/AU2012/001240 11 Table 5: Formulation E: 5mg/mi meloxicam liquid ge formulation Formulation E Ingredient Amount % w/v Meloxicam 0.5% Propylene glycol 37% Monoethanolamine 0.500% Methyl hydroxybenzoate 0.180% Propyl hydroxybenzoate 0.020% HPMC 1.000% (hydroxyproplmethylcellu lose) Water qs The method of preparing 1 L of the formulation includes the following steps: a. Charge an appropriate vessel with 400g of water and commence stirring at medium speed, to the water add the HPMC and mix to hydrate. 5 b. In a separate vessel collect the Propylene glycol, add to this the Methyl paraben and Propyl paraben. Mix and heat to dissolve (=<60C). Set aside to cool. c. To the cool paraben solution, add the meloxicam and mix to disperse. d. To the meloxicam dispersion, add the Monoethanolamine and mix until a 10 clear solution is obtained. e. Combine the two solutions. Mix until uniform. f. Make to volume and continue mixing until uniform. g. The viscosity of the formulation should be between 11,000cP and 18,OOOcP to prevent the formulation from being swallowed and to 15 maintain it against the cheek of the sheep. Example 6 - Formulation F: 2.5 mglmL meloxicam liquid gel for buccal/rectal administration The following constituents are used to make the meloxicam liquid gel 20 according to one embodiment of the present invention.

WO 2013/053015 PCT/AU2012/001240 12 Table 6 Formulation F - 2.5mg/mi meloxicam liquid gel for rectal/buccal administration Formulation F Ingredient Amount % w/v Meloxicam 0.25% Propylene glycol 37% Monoethanolamine 0.50% Benzyl alcohol 1.0% Natrosol HHX 1.0% (hydroxyethylcellulose) Water qs The method of preparing 1 L of the formulation includes the following steps: a. Collect the water in an appropriate vessel. 5 b. To the water add the hydroxyethylcellulose and mix until fully hydrated. c. In a separate vessel add the propylene glycol and disperse the meloxicam. d. Add the monoethanolamine and mix until a clear solution is obtained. e. Add benzyl alcohol. 10 f. Combine both phases and mix until uniform g. The viscosity of the formulation should be between 1 1,OOOcP and 18,OOOcP to prevent the formulation from being swallowed and to maintain it against the cheek of the sheep. 15 Example 7- Formulation G 10 mg/mL meloxicam liquid gel for buccal/rectal administration The following constituents are used to make the meloxicam liquid gel according to one embodiment of the present invention. 20 25 WO 2013/053015 PCT/AU2012/001240 13 Table 7 10mg.ml meloxicam liquid gel for buccal/rectal administration Formulation G Ingredient Amount % w/v Meloxicam 1.0% Propylene glycol 37% Monoethanolamine 0.50% Benzyl alcohol 1.0% Natrosol HHX 1.0% (hydroxyethylcellulose) Water qs The method of preparing 1 L of the formulation includes the following steps: a. Collect the water in an appropriate vessel. 5 b. To the water add the hydroxyethylcellulose and mix until fully hydrated. c. In a separate vessel add the propylene glycol and disperse the meloxicam. d. Add the monoethanolamine and mix until a clear solution is obtained. e. Add benzyl alcohol. 10 f. Combine both phases and mix until uniform g. The viscosity of the formulation should be between 9,500cP and 16,OOOcP to prevent the formulation from being swallowed and to maintain it against the cheek of the sheep. 15 Example -8 - Bioavailability of meloxicam administered via IV, IM and Oral Routes Investigation 1 Pharmacokinetics of Meloxicam in sheep administered 0.5mg meloxicam/kg bw via intravenous, intra-muscular and oral routes. In a preliminary study, the bioavailability of meloxicam following oral 20 administration to sheep was investigated. Sheep were randomly allocated to one of three groups each signifying a different route of administration, Group A (Intravenous - IV), Group B (Intramuscular - IM) or Group C (Oral-receiving suspended meloxicam).

WO 2013/053015 PCT/AU2012/001240 14 The dose of meloxicam investigated was 0.5mg/kg bodyweight. Injections of a commercially available 20mg/mL meloxicam (METACAM T M 20MG/ML SOLUTION FOR INJECTION) were administered intravenously into the jugular vein of Group A animals. A dose from the same commercially 5 available injection was administered intramuscularly to the gluteus muscle of Group B animals. An oral dose of the suspended meloxicam formulation, Formulation A of Example 1, was administered to the animal's mouth at the commissure of the lips and dose deposited at the back of the tongue. Blood samples were obtained from each animal immediately prior to 10 administration of the drugs and at 1, 2, 4, 8, 16, 30, 60, 120, 240, 360 minutes after, and again 24, 48 and 72 hours after treatment. Meloxicam concentrations in plasma were determined by Ultra High Performance Liquid Chromatography (UPLC) using Ultra-violet (UV) detection. Pharmacokinetic parameters were determined and the data presented in meloxicam concentration vs time curves 15 shown in Figs. 1 and 2 and in Table 8. Surprisingly, the pharmacokinetic parameters such as bioavailability and Mean Residence Time (MRT) associated with an oral dose of suspended meloxicam at 0.5mg meloxicam/kg bodyweight in a ruminant are similar to oral dose pharmacokinetic parameters obtained in other non-ruminant species, 20 dogs and horses. The significance of the oral MRT compared to IV, IM doses indicates that meloxicam absorbed orally is retained longer systemically, allowing it to exert its analgesic effect for a longer period than an equivalent dose administered by intravenous or intramuscular routes. 25 30 WO 2013/053015 PCT/AU2012/001240 15 Table 8 Pharmacokinetic parameters following IV, IM and Oral meloxicam 0.5mg/kg bw in sheep Intravenous (IV) Intramuscular (IM) Oral (Suspension) Metacam 20mg/ml Metacam 20mg/mI (Example 1) Meloxicam dose 0.5mg/kg bw 0.5mg/kg bw 0.5mg/kg bw Tmax min 120 360 Cmax ng/mL 1804 858 AUC(O-24hrs) 1570575 1770356 1219391 mg.min/mL MRT (area) min 775 1024 Bioavailability 113% 78% Example 9 - Pharmacokinetics of Meloxicam in sheep administered 5 0.5mg meloxicamlkg bw from various formulations and administration routes The objective of this study was to determine meloxicam concentrations in the plasma of sheep following oral or buccal administration of 0.5mg meloxicam/kg bw, from various formulas containing dissolved meloxicam. 10 Four adult merino ewes were selected for inclusion in the study. Each received a single dose of a formulation identified in the table below. Oral administration of the products involved drawing up the required dose into a syringe that was then introduced to the sheep's mouth at the commissure of the lips and the dose deposited at the back of the tongue. Where buccal 15 administration was required, the dose was drawn up into a syringe and administered into the space between the inside of the cheek and the molar teeth (buccal sulcus). Blood sampling occurred following drug administration to assess the plasma concentrations of meloxicam at the following timepoints: pre-treatment, 1 min, 2 mins, 4 mins, 8 mins, 16 mins, 30 mins, 1 hour,2 hours, 20 3 hours, 4 hours, 6 hours, 8 hours, 12 hours, 24 hours and 48 hours after treatment. Meloxicam concentrations in plasma were determined by Ultra High Performance Liquid Chromatography (UPLC) using Ultra-violet (UV) detection. Pharmacokinetic parameters were determined (Table 9) and the data WO 2013/053015 PCT/AU2012/001240 16 presented in meloxicam concentration vs time curves (Fig. 3), accompanied by an overlay of the oral dose in Example 1. Table 9 Pharmokinetic Parameters B C D E Meloxicam concentration 0.5% 0.25% 0.5% 0.5% Formulation Liquid gel Liquid Liquid Liquid gel gel Administration route Buccal Oral Buccal Buccal Dose rate mg meloxicam/kg bw 0.5 0.5 0.5 0.5 Tmax min 360 240 360 480 Cmax ng/mL 797 817 814 748

AUC(O.

48 hrs) ng.min/mL 1011759 746547 1043539 1026710 MRT (area) min 783 690 812 985 5 Surprisingly, the doses administered via buccal route demonstrate superior absorption to an orally administered solution of dissolved meloxicam. The absorption, and critical pharmacokinetic parameters Tmax, Cmax and Area Under Curve (AUC) is similar to those recorded following an oral dose of suspended meloxicam in the earlier study. 10 Example 10 Efficacy Of Meloxicam Buccal Liquid Gel As An Analgesic Agent During Mulesing Of Merino Lambs using Formulation F of Example 6 The study intended to assess the efficacy of the formulation F of 15 Example 6 when compared to Tri-Solfen@ (40.6 g/L Lignocaine hydrochloride, 4.2g/L Bupivacaine hydrochloride, 24.8 mg/L Adrenaline tartrate, 5.0 g/L Cetrimide), an existing product used for pain relief following mulesing, and a placebo. 34 male and female lambs of 6-8 weeks of age were recruited into the study. Each lamb weighed between 14-24kg. 20 Mulesing was carried out by trained contractors. The mulesing technique used was that described in detail in the National Mulesing Accreditation Program. This involved the removal of crescent shaped pieces of wool bearing skin from the base of the tail up towards either side of the perineal area, using sharp shears. In addition a strip of skin is removed from each side WO 2013/053015 PCT/AU2012/001240 17 of the tail. When performed by trained, experienced operators with sharp shears, each cut is performed very quickly in a single action, reducing the time of the procedure to a minimum. The resulting wound, when healed, increases the bare area while at the same time reducing the amount of wrinkle. The aim 5 is to keep the size of the wound to a minimum while still providing protection from flystrike, with a thin strip of wool bearing skin left between the mules and naturally bare area. Immediately prior to mulesing the lambs were weighed. The recorded weights were used to determine the dose of each product for each individual 10 animal. Lambs were randomly assigned to a treatment group as they were presented to the cradle for mulesing and subsequent administration of either Formulation F, Tri-Solfen or a placebo as set out in Table 10. The dose of Trisolfen administered was by reference to the size of the lamb as set out in 15 Table 11. It was administered by spraying the mulesed area. Similarly, the placebo was administered as a spray contained within a bottle indistinguishable from the Tri-Solfen administration bottle. Table 10 - Treatment and Control Groups Group 1 Formulation F via buccal administration plus coloured placebo spray Group 2 Tri-Solfen@ topically (POSITIVE CONTROL) Group 3 Coloured placebo spray only (NEGATIVE CONTROL) 20 Table 11 - Tri-Solfen Dosages Lamb size Required Dose Less than 10 kg 6 mIs 11-15kg 8 mIs 16-20 kg 10 mIs Over 20kg 12 mIs The dose of Formulation F provided to the lambs in group 1 was 0.5mg/kg of weight. Formulation F was gently shaken then drawn into a WO 2013/053015 PCT/AU2012/001240 18 syringe and deposited in the space between the molar teeth and the inside of the cheek (buccal route). In the study pain-related behaviour was assessed using a numerical rating scale at predetermined time points after mulesing. The numerical rating 5 scale is set out in Table 12. Assessments were made immediately after mulesing (0.5hr) and in the observation pen (Ohr, 1 hr, 2hr, 4hr, 8hr, 1 0hr, 24hr). Average results for each group are depicted in Fig. 4. The degree of association between variables (Time, Group and Pain 10 response) was assessed using the Phi coefficient. Immediately following mulesing there was a significant (Ps0.05 at least) reduction in pain response observed in the Tri-Solfen@ treated group (group 2). During this time period only sheep in the Formulation F treated group (group 1) showed signs of moderate pain, indicated by an increased pain observation level. In the 15 following 2 hours the Formulation F treated group (group 1) and placebo (group 3) had a significantly (Ps0.05) higher pain response in comparison to the Tri Solfen@ group (group 2). However, 2 hours post-mulesing there was a significant (P<0.001) increase in pain response in the placebo group (group 3), and a decrease in pain response in both the Tri-Solfen@(group 2) and 20 Formulation F treated group (group 1). Whilst the Formulation F treated group (group 1) lambs pain response remained consistent for the next 4 hours (up to 6 hours post-mulesing), the sheep in the Tri-Solfen@(group 2) and placebo groups (group 3) exhibited a steady increase in pain response. From 8 to 24 hours post mulesing 52% (Table 13) all sheep showed signs of mild-moderate 25 pain. 30 WO 2013/053015 PCT/AU2012/001240 19 Table 12 Numeric Rating Scale for Pain Grade Description of behaviour - initial - anticipated Modified to account severe pain response scale for less severe response seen in study lambs 0 no evidence of pain related behaviour no evidence of pain related behaviour 1 mildly abnormal posture, gait or behaviours mild such as - mild arching of the back without wide rear leg stance or extension of back legs, ventral lying with legs partially extended, mild stiffening of gait without overt limping or leg dragging 2 moderate abnormalities of posture, gait and moderate behaviours such as - statue standing head down with prominent arching of the back, prominent extension and/or abduction of hind legs, marked agitation with leg stamping, ventral lying with hind legs fully extended, limping or markedly abnormal gait with hind leg abduction and/or dragging, anorexia and lack of interest in feeding 3 extreme abnormalities of posture, gait and/or severe behaviour such as - rear leg collapse, dog sitting, lateral lying or lying with head flat, prominent tremors and shaking, inability to stand and/or marked and unusual leaning. Overall, the study indicated that whilst the Tri-Solfen@ treated animals exhibited a dimished pain response in the immediate hours (1-2) post mulesing, this reduction in pain response subsided by 4hrs, whereas the 5 Formulation F treated group had a more sustained and long-term reduction in pain. Those in the placebo group had a noticeably higher pain response in comparison to both other treated groups. All treatments appeared to diminish in affectability by 10hrs. 10 Example 11 - Tail Docking and Castration In a further example, the dose-effect relationship of meloxicam, when administered as the formulation detailed in Example 6 was investigated in lambs undergoing typical surgical husbandry procedures. The objective was to WO 2013/053015 PCT/AU2012/001240 20 observe and measure indicators of post-surgical pain in order to evaluate the analgesic and anti-inflammatory properties of increasing dose rates of meloxicam. Tail docking and knife castration 'marking' are on-farm animal husbandry 5 procedures conducted on most lambs produced in Australia. In this study, the physiological, clinical and behavioural response of individual lambs to marking was assessed as an indicator of the effectiveness of meloxicam administered via the oral trans mucosal route, using Example 6 at 0.25, 0.50 and 1.0mg/kg bw. Baseline data for comparison, was obtained using two control groups; one 10 administered a placebo (Example formulation 6 without meloxicam) prior to surgery, and one group administered a placebo (Example formulation 6 without meloxicam), handled without undergoing the surgical procedure. Table 13. Treatment groups Group Treatment Dose Rate Dose No. Volume lambs 1 Controls, handled + Placebo - 0.2 mL/kg 12 2 Placebo + castration and tail ~- 0.2 mL/ kg 12 docking 3 Meloxicam + castration and 0.25 mg 0.1 mL/ kg 12 tail docking meloxicam/kg 4 Meloxicam + castration and 0.50 mg 0.2 mL/ kg 12 tail docking meloxicam/kg 5 Meloxicam + castration and 1.0 mg 0.4 mL/ kg 12 tail docking meloxicam/kg 15 Sixty weaned, entire male lambs were selected for inclusion in the blinded controlled randomized block design study. The study comprised three cohorts of 20 lambs, treated and studied over a 14 day period. Within each cohort, the lambs were ranked according to weight, stratified on bodyweight 20 into blocks of 5 and randomly allocated from within each block to 5 treatment groups. Animals were treated according to the treatment regime detailed in Table 13. The test formulation and placebo were administered once only. Treatment administration, volume and time of application were recorded for WO 2013/053015 PCT/AU2012/001240 21 each animal. The formulation detailed in Example 6 or the placebo was administered by the oral trans mucosal route by syringe. The dose was applied into the sulcus between the molar teeth and the inside of the cheek. After the lamb had received the formulation, the appropriate castration and tail docking 5 or control sham treatment was carried out. Lambs were placed on their back in a lamb marking cradle within the animal house for 60s for castration. Knife castration was performed by cutting off the lower half of the scrotum with a knife then pulling out the testes with the aid of a hook on the knife. Tail docking was performed below the third palpable 10 joint with a Primus BJ5000 hot knife. Control lambs were placed on their back in the lambing cradle and the scrotum and tail gently handled. Video cameras were used to continuously record the behaviour of lambs in the study. For each pen, one camera was mounted on roofing rafters at each end of the pen. Each camera provided a view of the entire area available to the 15 lambs. The cameras were connected to digital video recorders and captured by behaviour of the lambs in their pens on Days 0-3. Behaviour of the lambs was classified every 15 minutes for 12 hours per day from the time of marking or sham treatment, to 3 days post-procedure. The postures classified were: normal ventral lying, abnormal ventral lying, 20 ventral lying other, lateral lying, abnormal lying, total lying, normal standing, statue standing, abnormal standing, standing other, normal walking, abnormal walking, walking other, feeding at the trough, total standing, total abnormal behaviours. All behaviour assessments were conducted from the video recordings and carried out by a single staff member trained in categorising 25 behaviours. The person performing the video observations post-treatment was blinded as to treatment. In the weeks prior to treatment, all lambs had their necks clipped to facilitate blood sampling by jugular venipuncture. Blood was collected at -24h, Oh, 6h, 12h, 24h, 48h and 72h time-points relative to the commencement of the 30 treatments. Staff collecting blood samples were blinded as to treatment. The results of the current study indicated that there was a significant effect of treatment (P < 0.001) and time (P < 0.001) and a significant treatment WO 2013/053015 PCT/AU2012/001240 22 by time interaction (P = 0.001). Marked lambs generally spent more time in total abnormal postures than Sham lambs throughout the observation period, however, Meloxicam 0.25 mg/kg and Meloxicam 1.0 mg/kg groups spent significantly less time in total abnormal behaviours than Placebo group in the 5 intervals from 0-8 h. The results of the current study indicate that Meloxicam ameliorated postural changes associated with pain indicating that it had an analgesic effect. Effect on postural indicators of pain were all observed on Day 1, with the exception of a tendency for lambs receiving 1.0 mg/kg to spend more time feeding at the trough on Day 2 as well as Day 1. 10 Marking caused an increase in total white cell count that was mostly associated with an increase in neutrophils while at the same time there was a decrease in lymphocytes and eosinophils. These are typical responses following acute tissue damage and stress. The data for neutrophil count and neutrophil to lymphocyte ratio indicated that meloxicam treatment improved 15 these variables at 0.25, 0.5 and 1.0 mg/kg dose rates. There was also a pronounced increase in haptoglobin in response to marking. This response is typical of the damage seen following tissue trauma associated with mulesing and knife castration. In the current study, Meloxicam 1.0 mg/kg significantly reduced the increase in haptoglobin. 20 Total white cell and eosinophil counts were also performed and statistically significant improvements noted at various time-points in the 0.5mg/ml and 1.0mg/ml treatment groups. The effects of Meloxicam on neutrophils, and neutrophil to lymphocyte ratio, haptoglobin, total white cell and eosinophil counts are evidence of anti 25 inflammatory effects of the drug. EXAMPLE 12 - Pharmacokinetics 1% Liquid Gel Formulation G from Example 7 A further example is cited in which Formulation G from Example 7 was 30 administered in a two-period, two-sequence pharmacokinetic study in lambs. The objective of the study was (1) to determine concentrations of meloxicam in plasma resulting from intramuscular (IM) and buccal (OTM, Oral Trans WO 2013/053015 PCT/AU2012/001240 23 Mucosal) administration of meloxicam at 1.0mg/kg; and (2) compare resultant pharmacokinetic parameters such as Area Under Curve (AUC), Cmax and Tmax to determine if the combination of the Formulation G from Example 7 and administration route, could be a viable alternative to injectable meloxicam 5 for analgesia at the time of surgical husbandry. 12 lambs were randomly allocated into two treatment groups (A and B) of 6 lambs in each group based on weight. Group A lambs received the Reference Treatment, 1.0mg meloxicam/kg intramuscularly (IM); Group B received Formulation G from Example 7 administered at 1.0mg meloxicam/kg 10 between the molar teeth and the inside of the cheek (buccal). On Day 10, after a washing out period of 10 days, the treatments were reversed for the two groups. During each period, blood samples were collected pre-treatment on Days 0 and 10 and then at 1, 5, 10, 15, 30, 45, 60, 75, 90, 105, 120 min; 3, 4, 8, 10, 12, 24, 48, 72 and 96 hours post-treatment. Plasma was extracted and 15 analysed. Meloxicam concentrations in plasma were determined using a validated analytical procedure with instrumental determination by Ultra High Performance Liquid Chromatography - electrospray ionisation-tandem mass spectrometry. The Lower Limit of Quantitation (LLOQ) for the method in ovine plasma was 20 established at 10ng/mL for meloxicam. The pharmacokinetic parameters AUC, Cmax, Tmax were defined for each test subject and tabulated by route of administration in Tables 14 and 15. Overlaid Plots of concentration vs time for each period and sequence are presented in Figure 5. A plot of average concentrations (by route of 25 administration) vs time is provided in Figure 6. The bioavailability of meloxicam administered in the form of Formulation G from Example 7 by the oral trans mucosal route (buccal) was expressed as a percentage of AUC determined in lambs receiving an equivalent dose by the intramuscular route. The resultant bioavailability of meloxicam was calculated 30 to be 80% (Table 16). The extensive absorption of meloxicam following buccal administration of the Formulation G from Example 7 indicates that this method of WO 2013/053015 PCT/AU2012/001240 24 administration would be a viable, safe and efficient method of providing analgesia to lambs immediately prior to the conduct of surgical husbandry procedures. 5 Table 14: Pharmacokinetic parameters by administration route Meloxicam - Oral trans mucosal (OTM) AUC (o-t) AUC. Cmax Tmax Animal (ng- (ng Period Sequence Treatment No. hr/mL) hr/mL) ng/mL hours 1 1 OTM 5 53602 53860 2563 3 1 1 OTM 78 58594 59110 2326 2 1 1 OTM 111 50042 50204 2417 3 1 1 OTM 205 30699 30762 1088 4 1 1 OTM 324 46373 47239 1272 3 1 1 OTM 641 44370 44444 2693 1.5 2 2 OTM 16 32516 3146 1301 2 2 2 OTM (24) 33915 33971 1214 2 2 2 OTM (87) 34675 35055 1213 1 2 2 OTM 138 37329 37376 2231 3 2 2 OTM 154 39442 40071 1620 4 2 2 OTM (601) 27943 28004 1824 3 OTM Treatment Average 40792 L41104 1814 2.6 (No)=Spare animals substituted for animals in Period 1 10 Table 15:Pharmacokinetic parameters by administration route Meloxicam - Intramuscular injection (IM) AUC (0-t) AUC-o Cmax Tmax Animal (ng- (ng Period Sequence Treatment No. hr/mL) hr/mL) ng/mL hours 2 1 IM 5 51691 51813 3876 1 2 1 IM 78 70968 71804 5358 1 2 1 IM 111 49907 50068 4303 1.5 2 1 IM 205 40107 40233 3718 1.5 2 1 IM 324 41668 41972 2048 2 2 1 IM 641 52484 52537 6944 0.5 1 2 IM 16 56984 57607 3221 2 1 2 IM 21 34943 35240 2901 1.5 1 2 IM 31 61502 61743 4218 1 1 2 IM 123 42377 42465 2738 2 1 2 IM 138 46911 46974 4042 1 1 2 IM 154 44099 44407 3641 1.5 IM Treatment Average 49470 49739 3917 1.4 WO 2013/053015 PCT/AU2012/001240 25 Table 16: Bioavailability Calculation - Meloxicam AUC (-t) AUC. (ng-hr/mL) (ng-hr/mL) OTM Treatment Average 40792 41104 IM Treatment Average 49470 49739 Bioavailability 82% 83% There have been described and illustrated herein several embodiments. While particular embodiments of the invention have been described, it is not 5 intended that the invention be limited thereto. It is intended that the invention be broad in scope as the art will allow and that the specification be read likewise. Thus, whilst examples of formulations have been disclosed, it will now be appreciated that other formulation can be used as well. It will therefore be appreciated by those skilled in the art that yet other modifications could be 10 made to the formulations and method of use without deviating from the spirit and scope as claimed. INDUSTRIAL APPLICABILITY The present invention has general applicability in the field of veterinary pharmacology and the treatment of animals by veterinarians.

Claims (23)

1. A method of providing analgesia or controlling inflammation in sheep when the sheep are undergoing a painful surgical procedure selected from the group consisting of tail docking, castration, and mulesing, wherein the method comprises administering to the sheep a therapeutically effective amount of a liquid gel formulation containing pharmacologically acceptable meloxicam or meloxicam salt, and wherein the formulation is administered via the buccal or oral route.

2. The method of claim 1 wherein the dose of meloxicam or meloxicam salt contained in the formulation is in the range of 0.25 mg/kg to 1.0 mg/kg of bodyweight of the sheep.

3. The method of claim 2 wherein the dose is in the range of 0.5 mg/kg to 1.0 mg/kg of bodyweight of the sheep.

4. The method of claim 3 wherein the dose is 1.0 mg/kg of bodyweight of the sheep.

5. The method of claim 1 wherein the concentration of meloxicam or meloxicam salt contained in the formulation is between 0.25% and 1% (w/v).

6. The method of any one of claims I to 5 wherein the meloxicam or meloxicam salt contained in the formulation is present, at least partially, suspended in the solid phase, and where the formulation is administered to the sheep via the oral route. 04/04/16 27

7. The method of any one of claims 1 to 6 wherein the formulation contains one or more of viscosity modifiers, suspending agents, buffers, pH modifying agents, sweeteners, preservatives and solubilisers.

8. The method of any one of claims 1 to 7 wherein the formulation additionally comprises glycerol, xylitol, sodium benzoate, citric acid, sodium dihydrogen phosphate, sodium saccharin, xanthan gum, sorbitol and water.

9. The method of any one of claims 1 to 5 wherein the meloxicam or meloxicam salt contained in the formulation is dissolved, and where the formulation is administered to the sheep via the buccal route.

10. The method of claim 9 wherein the formulation contains dissolved meloxicam salt.

11. The method of claim 10 wherein the meloxicam salt is the salt of meloxicam and an inorganic or organic base.

12. The method of claim 11 wherein the base is selected from the group consisting of megiumine, monoethanolamine and lysine.

13. The method of claim 12 wherein the base is selected from the group consisting of meglumine and monoethanolamine.

14. The method of any one of claims 9 to 13 wherein the formulation contains one or more of solubilisers, preservatives, thickeners, gelling agents, pH modifying agents and buffers. 04/04116 28

15. The method of any one of claims 9 to 14 wherein the formulation additionally comprises propylene glycol, benzy alcohol and hydroxyethylcelIlulose.

16. The method of any one of claims 9 to 14 wherein the formulation additionally comprises propylene glycol, methyl hydroxybenzoate, propyl hydroxybenzoate and hydroxypropylmethylcellulose.

17. The method of any one of claims 9 to 14 wherein the formulation additionally comprises ethanol and hydroxyethylcellulose.

18. The method of any one of claims 9 to 14 wherein the formulation is instead administered to the sheep via the oral route.

19. The method of claim 18 wherein the formulation comprises an aqueous solution of a meloxicam meglumine salt and ethanol.

20. The use of a therapeutically effective amount of a liquid gel formulation containing pharmacologically acceptable meloxicam or meloxicam salt in the manufacture of a medicament to be administered via the buccal or oral route for providing analgesia or controlling inflammation in sheep when the sheep are undergoing a painful surgical procedure selected from the group consisting of tail docking, castration, and mulesing.

21. The use of claim 20 wherein the concentration of meloxicam or meloxicam salt contained in the formulation is between 0.25% and 1% (w/v). 04/04/16 29

22. The use of claim 20 or claim 21 wherein the formulation is administered to the sheep via the buccal route.

23. The use of claim 20 or claim 21 wherein the meloxicam or meloxicam salt contained in the formulation is present, at least partially, suspended in the solid phase, or is dissolved, and wherein the formulation is administered to the sheep via the oral route. 04/04/16