AU2010317667B2

AU2010317667B2 - Drug combination with theobromine and its use in therapy

Info

Publication number: AU2010317667B2
Application number: AU2010317667A
Authority: AU
Inventors: Robin Mark Bannister; John Brew
Original assignee: Infirst Healthcare Ltd
Current assignee: Infirst Healthcare Ltd
Priority date: 2009-11-13
Filing date: 2010-11-12
Publication date: 2014-05-29
Anticipated expiration: 2030-11-12
Also published as: GB0919889D0; CN102753174A; PE20130147A1; BR112012011227A2; WO2011058373A2; JP6118919B2; UA108993C2; JP2016128439A; ZA201204248B; NZ599949A; IL219768A0; RU2519086C2; WO2011058373A3; CA2780703A1; CO6551744A2; EP2498777A2; AU2010317667A1; RU2012124038A; MX2012005532A; JP2013510841A

Abstract

An agent comprises theobromine and another non-opiate antitussive, for simultaneous, sequential or separate use in therapy. Preferably, the therapy is of cough.

Description

WO 2011/058373 PCT/GB2010/051895 1 DRUG COMBINATION WITH THEOBROMINE AND ITS USE IN THERAPY Field of the Invention This invention relates to a drug combination, its composition and its use 5 in the therapy of cough. Background of the Invention Cough is a protective reflex. Persistent cough can be distressing. Over the-counter remedies are available but their effectiveness is doubtful. W098/42322 discloses the use of theobromine for the treatment of 10 cough, to be given orally. Usmeni et al., FASEB J. express acticle 10.1096, discloses that theobromine inhibits sensory nerve action and cough. Data are provided, showing effects following oral dosing in citric-acid induced cough in the guinea pig, and in the capsaicin cough challenge in humans, and following bathing of isolated guinea pig vagus nerve preparations. 15 A number of non-opiate antitussive drugs have been developed for cough therapies. A number of these antitussive drugs are NMDA antagonists. Dextromethorphan is one such drug that has been developed specifically for use as a cough therapy. However, its efficacy and suitability as a treatment for cough has already been brought into question. In J. Ramsey et al., British 20 Journal of Clinical Pharmacology, the authors report that the apparent success of dextromethorphan as a clinical treatment for cough is in fact just a placebo effect, and that it has no efficacy in cough. Summary of the Invention The invention is based at least in part on data showing a synergistic anti 25 tussive effect for theobromine combined with the non-opiate antitussive drug, dextromethorphan, in a citric acid-induced cough model. The data show that when theobromine is combined with dextromethorphan, the effect is surprisingly potent and greater than the sum of the individual drugs, revealing that the combination has a substantially improved effect. 30 Consequently, a considerably reduced dose of both drugs can be given for an equivalent effect for each individual drug, so reducing side-effects and drug burden. One such side-effect of dextromethorphan, and many other non opiate antitussives is sedation. It has surprisingly been found that theobromine counteracts the sedative properties of such drugs.

WO 2011/058373 PCT/GB2010/051895 2 Therefore, according to the present invention, an agent comprises theobromine and another non-opiate antitussive, as a combined preparation for simultaneous, sequential or separate use in therapy. It is believed that this synergistic relationship will be exhibited by all non 5 opiate antitussives. Without wishing to be bound by theory, this may be because non-opiate antitussives act via a similar mechanism, which may be NMDA antagonism. Description of the Drawing Figure 1 shows the effect of theobromine, and a combination of 10 theobromine and dextromethorphan, on citric acid-induced cough in guinea-pig. Description of the Invention Any suitable form of theobromine can be chosen. These include salts, prodrugs and active metabolites. Theobromine may also be in the form of cocoa or chocolate. Suitable dose ranges for theobromine are known in the art, 15 although the synergistic effect of the combination means that the effective dose may be reduced. The additional agent (a different non-opiate antitussive drug, i.e. not theobromine) may be used in an amount that is already known for its use, although combination according to this invention means that a reduced dose 20 may be effective. Preferably, the dose of the non -opiate antitussive that is administered with the theobromine is greater than 0.1, e.g. more than 5, and typically up to 30 mg/kg/day. The non-opiate antitussive drug is preferably selected from dextromethorphan, isoaminile, benzonate, zipeprol, morclofone, prenoxdiazine, 25 dropropizine, piperidione, pentoxyverine, oxolamine, oxeladin, nepinalone, meprotixol, indantadol, dimemorfan, dibunate, cloperastine, clofedanol, butamirate, bibenzonium, benproperine and fedrilate. Dextromethorphan is the most preferred antitussive drug, e.g. at a dose of 0.1 to 6 mg/kg/day. The non-opiate antitussive drug is preferably an NMDA antagonist. 30 The compounds of the invention may be administered by any available route, such as via the oral, inhaled, intranasal, sublingual, intravenous, rectal and vaginal routes. The oral route is the preferred route of administration. The compounds of the invention are preferably as combinations to be administered orally, for example as tables, troches, lozenges, aqueous or oral WO 2011/058373 PCT/GB2010/051895 3 suspensions, dispersible powders or granules. Preferred pharmaceutical compositions of the invention are tablets and capsules. Liquid dispersions for oral administration may be syrups, emulsions and suspensions. More preferably, the pharmaceutical composition of the combination is a pressed 5 tablet or capsule with conventional excipients, examples of which are given below. Compositions of the combination intended for oral use may be prepared according to any method known to the art for the manufacture of pharmaceutical compositions, and such compositions may contain one or more agents selected 10 from the group consisting of sweetening agents, flavouring agents, colouring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets contain the combined active ingredients in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture of tablets. These excipients may be, for example, 15 inert diluents, such as calcium carbonate, sodium carbonate, lactose, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example corn starch or alginic acid; binding agents, for example starch gelatin, acacia, microcrystalline cellulose or polyvinyl pyrrolidone; and lubricating agents, for example magnesium stearate, stearic acid or talc. The tablets may be 20 uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate may be employed. Aqueous suspensions contain the combined active materials in admixture 25 with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, sodium alginate, polyvinyl pyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be a naturally occurring phosphatide, for example lecithin, or condensation 30 products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long-chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids, for example polyoxyethylene sorbitan monooleate. The aqueous suspensions may also WO 2011/058373 PCT/GB2010/051895 4 contain one or more preservatives, for example ethyl or n-propyl p hydroxybenzoate, one or more colouring agents, one or more flavouring agents, and one or more sweetening agents, such as sucrose or saccharin. Oily suspensions may be formulated by suspending the active ingredient 5 in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, polyoxyethylene hydrogenated castor oil, fatty acids such as oleic acid, or in a mineral oil such as liquid paraffin or in other surfactants or detergents. The oily suspensions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents, such as those set forth above, and 10 flavouring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an antioxidant such as ascorbic acid. Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the combined active ingredients in 15 admixture with a dispersing or wetting agent, suspending agent and one or more preservatives. Suitable sweetening, flavouring and colouring agents may also be present. The combined pharmaceutical compositions of the invention may also be in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, for 20 example olive oil or arachis oil, or a mineral oil, for example liquid paraffin, or mixtures of these. Suitable emulsifying agents may be naturally occurring gums, for example gum acacia or gum tragacanth, naturally occurring phosphatides, for example soya bean, lecithin, and esters or partial esters derived from fatty acids and hexitol anhydrides, for example sorbitan monooleate and condensation 25 products of the said partial esters with ethylene oxide, for example polyoxyethylene sorbitan monooleate. The emulsions may also contain sweetening and flavouring agents. Syrups and elixirs may be formulated with sweetening agents, for example glycerol, propylene glycol, sorbitol or sucrose. Such formulations may 30 also contain a demulcent, a preservative, flavouring and colouring agents. Suspensions and emulsions may contain a carrier, for example a natural gum, agar, sodium alginate, pectin, methylcellulose, carboxymethylcellulose, or polyvinyl alcohol.

WO 2011/058373 PCT/GB2010/051895 5 In a preferred embodiment, theobromine in combination with an antitussive drug is to be administered via the oral route. Combined compositions according to the invention may be produced using conventional formulation techniques. In particular, spray-drying may be used to produce microparticles 5 comprising the active agent dispersed or suspended within a material that provides the controlled release properties. The process of milling, for example jet milling, may also be used to formulate the therapeutic composition. The manufacture of fine particles by milling can be achieved using conventional techniques. The term "milling" is 10 used herein to refer to any mechanical process which applies sufficient force to the particles of active material to break or grind the particles down into fine particles. Various milling devices and conditions are suitable for use in the production of the compositions of the invention. The selection of appropriate milling conditions, for example, intensity of milling and duration, to provide the 15 required degree of force, will be within the ability of the skilled person. Ball milling is a preferred method. Alternatively, a high pressure homogeniser may be used, in which a fluid containing the particles is forced through a valve at high pressure, producing conditions of high shear and turbulence. Shear forces on the particles, impacts between the particles and machine surfaces or other 20 particles, and cavitation due to acceleration of the fluid, may all contribute to the fracture of the particles. Suitable homogenisers include the EmulsiFlex high pressure homogeniser, the Niro Soavi high pressure homogeniser and the Microfluidics Microfluidiser. The milling process can be used to provide the microparticles with mass median aerodynamic diameters as specified above. If 25 hygroscopic, the active agent may be milled with a hydrophobic material, as stated above. If it is required, the microparticles produced by the milling step can then be formulated with an additional excipient. This may be achieved by a spray drying process, e.g. co-spray-drying. In this embodiment, the particles are 30 suspended in a solvent and co-spray-dried with a solution or suspension of the additional excipient. Preferred additional excipients include polysaccharides. Additional pharmaceutically effective excipients may also be used. Compositions of the combination intended for inhaled, topical, intranasal, intravenous, sublingual, rectal and vaginal use may be prepared according to WO 2011/058373 PCT/GB2010/051895 6 any method known to the art for the manufacture of pharmaceutical compositions. Therapy according to the invention may be conducted in generally known manner, depending on various factors, such as the sex, age or condition of the 5 patient, and the existence or otherwise of one or more concomitant therapies. The patient population may be important. The present invention is based at least in part on the following study. Study Cough was induced in guinea pigs by the use of citric acid. One group of 10 guinea pigs was administered 10 mg/kg of theobromine, and a second group was administered 10 mg/kg of theobromine in combination with 30 mg/kg of dextromethorphan. A third group was used as a control, receiving only vehicle. Administration was via the oral route. The results are shown in Figure 1. The data show that a combination of 15 theobromine and dextromethorphan has improved efficacy in cough therapy when compared to theobromine monotherapy (shown in the Figure) and dextromethorphan monotherapy (recently reported to have no effect in cough).

7 In the specification the term "comprising" shall be understood to have a broad meaning similar to the term "including" and will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. This definition also applies to variations on the term "comprising" such as "comprise" and "comprises." The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the referenced prior art forms part of the common general knowledge in Australia.

Claims

1. An agent consisting of theobromine and a non-opiate antitussive as a combined admixture preparation for use in a therapy for cough.

2. The agent according to claim 1, wherein the non-opiate antitussive is a N methyl-D-aspartate receptor antagonist.

3. The agent according to claim 1, wherein the non-opiate antitussive is dextromethorphan, isoaminile, benzonatate, zipeprol, morclofone, prenoxdiazine, dropropizine, piperidione, pentoxyverine, oxolamine, oxeladin, nepinalone, meprotixol, indantadol, dimemorfan, dibunate, cloperastine, clofedanol, butamirate, bibenzonium, benproperine or fedrilate.

4. The agent according to any one of claims 1-3, wherein the non-opiate antitussive is dextromethorphan.

5. The agent according to any one of claims 1-3, wherein the non-opiate antitussive is to be administered in a dose of 0.1 to 30 mg/kg/day.

6. The agent according to claim 3 or claim 4, wherein the dextromethorphan is to be administered in a dose of 0.1 to 6 mg/kg/day.

7. The agent according to any one of claims 1-6 manufactured for oral administration.

8. The agent according to any one of claims 1-6 prepared as a tablet, capsule, troche, lozenge, powder, granule, suspension, syrup or emulsion.

9. A pharmaceutical composition comprising the agent of any one of claims 1-6 for use in a therapy of cough.

10. The pharmaceutical composition according to claim 9, further comprising one or more excipients, and optionally one or more of sweetening agents, flavoring agents, coloring agents and/or preserving agents.

11. The pharmaceutical composition according to claim 9 or claim 10 manufactured for oral administration.

12. The pharmaceutical composition according to any one of claims 9-11 prepared as a tablet, capsule, troche, lozenge, powder, granule, suspension, syrup or emulsion.

13. Use of an agent in the manufacture of a medicament for use in a therapy of cough, wherein the agent consists of theobromine and a non-opiate antitussive.

14. The use according to claim 13, wherein the non-opiate antitussive is a N methyl-D-aspartate receptor antagonist.

15. The use according to claim 13, wherein the non-opiate antitussive is 9 dextromethorphan, isoaminile, benzonatate, zipeprol, morclofone, prenoxdiazine, dropropizine, piperidione, pentoxyverine, oxolamine, oxeladin, nepinalone, meprotixol, indantadol, dimemorfan, dibunate, cloperastine, clofedanol, butamirate, bibenzonium, benproperine or fedrilate.

16. The use according to any one of claims 13-15, wherein the non-opiate antitussive is dextromethorphan.

17. The use according to any one of claims 13 to 16, wherein the medicament is manufactured for oral administration.

18. The use according to any one of claims 13-16, wherein the medicament is prepared as a tablet, capsule, troche, lozenge, powder, granule, suspension, syrup or emulsion.

19. Use of an agent in a therapy of cough, wherein the agent consists of theobromine and a non-opiate antitussive.

20. The use according to claim 19, wherein the non-opiate antitussive is a N methyl-D-aspartate receptor antagonist.

21. The use according to claim 19, wherein the non-opiate antitussive is dextromethorphan, isoaminile, benzonatate, zipeprol, morclofone, prenoxdiazine, dropropizine, piperidione, pentoxyverine, oxolamine, oxeladin, nepinalone, meprotixol, indantadol, dimemorfan, dibunate, cloperastine, clofedanol, butamirate, bibenzonium, benproperine or fedrilate.

22. The use according to any one of claims 19-21, wherein the non-opiate antitussive is dextromethorphan.

23. The use according to any one of claims 19-21, wherein the non-opiate antitussive is to be administered in a dose of 0.1 to 30 mg/kg/day.

24. The use according to claim 21 or claim 22, wherein the dextromethorphan is to be administered in a dose of 0.1 to 6 mg/kg/day.

25. A method of treating a cough, the method comprising the step of administering to an individual in need thereof an agent as defined in any one of claims 1-8.

26. A method of treating a cough, the method comprising the step of administering to an individual in need thereof a pharmaceutical composition as defined in any one of claims 9-12.