WO2014036165A1 - Aqueous based compositions for treating otitis externa - Google Patents

Description

AQUEOUS BASED COMPOSITIONS FOR TREATING OTITIS EXTERNA

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. provisional application serial number 61/694,704, filed August 29, 2012, which is hereby incorporated by reference in its entirety, including all tables, figures, and claims.

FIELD OF THE FNVENTION

[0002] The present invention relates generally to non-invasive methods and compositions for treating otitis externa (outer ear infection or infestation and inflammation) and, more specifically, to an aqueous otic combination formulated for a single dose regimen.

BACKGROUND OF THE INVENTION

[0003] Millions of animals and people, particularly children, are affected each year with otitis externa, an infection and/or infestation of the outer ear, often accompanied by painful inflammation of the affected tissue. Animals with ear flaps, such as many breeds of dogs, are especially susceptible. Their covered outer ear canals provide a hospitable environment for microbes to breed and inflammation to form, yet caretakers may not notice the condition as readily as in raised ear animals.

[0004] A variety of bacteria, viruses and fungi can be responsible for causing otitis externa. Often first-line treatment is limited to oral or topical antibiotics. The use of orally administered medications may be diluted by the systemic distribution of the drug, and could place the patient at risk for side effects associated with systemic delivery (e.g., yeast infections in females). Yet the risk for fungal overgrowth in the ear canals of patients treated only with topical antibiotics for bacterial infections emphasizes a need for careful diagnosis and treatment of all the causative agents associated with otitis externa and its sequalae (Schraeder and Issacson, Pediatrics, 111(5): 1123, 2003). As such, a preference is emerging for multiple agent topical treatment of otitis externa, especially in children and animals in whom compliance with a long-term oral dosing regimen can be difficult to obtain.

[0005] When single or multiple active agents are applied topically to treat otitis externa, efficacy often depends on how long the medication can be maintained in contact with the affected tissue, especially when a fungal or parasitic infestation (e.g., ear mites) is present. Conventional ear drops are problematic because the tissues they contact are directly affected by the attitude of the patient's head, and the drops can easily flow out of the ear with movement. Approaches to increasing the residence time of topical medications in the external ear canal have included use of flowable gels made more adhesive with viscocity- enhancing agents such as cellulose (e.g., hydroxypropyl methylcellulose), gel plugs, mousses, foams, or other formulations with adhesive properties.

[0006] However, compliance with dosing regimes using such formulations is again an issue, as their thick and/or sticky feel in the ear may be a source of frustration, especially to animals and young children. If acceptance of a retainable topical formulation isn't possible, the remaining option is often more frequent, and less convenient, dosing with less viscous solutions, such as conventional ear drops. Current courses of treatment for otitis externa include multi-dose administration to subjects suffering from infection, e.g., applying a topical formulation daily for several days. Non-compliance with multi-dose regimens is a common occurrence, and in the case of, e.g., bacterial or fungal infections has profound implications. Poor treatment compliance and ineffective management of otitis externa can lead to the emergence of drug resistant microorganisms and the eventual deterioration of a patient's health.

[0007] A need, therefore, exists for an approach to topical treatment of otitis externa which can be applied infrequently, preferably only once, to ameliorate (significantly reduce symptoms) or resolve the condition. Preferably, such a formulation will not rely on use of gels, cellulose-based or adhesive compositions to increase viscocity for retention in the ear.

SUMMARY OF THE INVENTION

[0008] The present invention is based on the seminal discovery that acute otitis externa in an afflicted subject may be clinically cured with a single dose treatment regimen. One dose of a formulation containing a combination of active agents in aqueous solution applied topically to affected subjects is effective in the treatment of otitis externa.

[0009] Provided herein are methods for treating or preventing otitis externa infection and sequelae, by administering, to a subject in need thereof, an aqueous pharmaceutical dosage form. In certain aspects, the pharmaceutical dosage form is administered topically to, by way of example, the outer ear canal of the subject. In another aspect, the aqueous pharmaceutical dosage form is a solution. In yet another aspect, the pharmaceutical dosage form is administered as a single dose, with such dose being sufficient to resolve, or substantially resolve, an existing infection or prevent the onset, or reoccurrence, of an infection without introduction of a further infective agent.

[0010] The amount of the pharmaceutical dosage form to be administered to the subject may be in quantities of, for example, about 0.5 ml to 5 ml, and all dosage ranges in between. It will be understood, however, that lower or higher dosages may be administered in accord with the clinical judgment of a healthcare professional.

[0011] The aqueous pharmaceutical dosage form includes a therapeutically effective amount of at least two active agents, such as antibiotics, anti-fungals, anti-parasitics, anti- virals, non-steroidal anti-inflammatories, analgesics, anesthetics, steroids, and the like.

Examples of the antibiotics contemplated herein include, but are not limited to, quinolone antibiotics, penicillin antibiotics, macrolide antibiotics, cephalosporin antibiotics, sulfa antibiotics, beta-lactamase inhibitors, and bacteriostatic antibiotics. By way of example, allylamine anti-fungals are included in the pharmaceutical dosage form of the disclosed methods. In one aspect, the pharmaceutical dosage form includes three active ingredients, such as an antibiotic, an anti-fungal, and a steroid. In one embodiment, the pharmaceutical dosage form contains florfenicol, terbinafme, and mometasone furoate.

[0012] In one embodiment, the pharmaceutical dosage form contains about 1.0 to 2.0% (w/w) terbinafme and about 0.1 to 0.5% (w/w) mometasone furoate in aqueous solution. The pharmaceutical dosage form used in the present methods also contains excipients including, but not limited to, propylene carbonate, propylene glycol, PEG 8000, and alcohol.

[0013] In certain aspects, the subject is a mammal, such as a domestic animal or human. In one embodiment, the subject is a dog.

[0014] The summary of the invention described above is not limiting and other features and advantages of the invention will be apparent from the following detailed description of the embodiments, as well as from the claims.

DETAILED DESCRIPTION OF THE INVENTION

[0015] The invention provides a multiple agent composition for treating antibiotic or parasitic infections, fungal infestations, and inflammation which can be placed into and retained in the ear for a sufficient length of time to treat otitis externa without use of a gel, cellulose or other adhesive formulation. Surprisingly, it has been found that aqueous formulations of the invention can be applied topically once to the afflicted subject and effectively resolve the treated condition entirely.

[0015] Preferred medicaments for delivery according to the invention are those useful in the treatment or prevention of otitis externa and its sequelae (such as pruritis). The invention is particularly well-suited to the delivery of medicaments such as antibiotics or anti-viral agents (depending on the source of the infection present), anti-fungal agents, and antiinflammatory agents or other painkillers. For prevention of chronically recurring external ear infections, the methods of the invention may also be utilized between active infections to deliver prophylactic agents to the outer ear canal.

[0016] The invention is suitable for practice in the treatment of otitis externa in animals and humans. In addition to primates, such as humans, a variety of other mammals can be treated according to the method of the disclosure. For instance, mammals including, but not limited to, cows, sheep, goats, horses, dogs, cats, guinea pigs, rats or other bovine, ovine, equine, canine, feline, rodent or murine species can be treated. However, the method can also be practiced in other species, such as avian species (e.g., chickens).

[0017] The term "therapeutically effective amount" means the amount of the compound or pharmaceutical composition that will elicit the biological or medical response of a tissue, system, animal or human that is being sought by the researcher, veterinarian, medical doctor or other clinician; e.g., single dose substantial resolution of otitis externa and its sequalae to a degree sufficient to constitute treatment to a clinically significant extent. Most preferable, a therapeutically effective amount will be one in which, when administered in a single dose, prevents or resolves an infection to a degree sufficient to avoid reoccurrence without introduction of additional infective agents into the ear. A clinical score of less than 3 as described in Example II below is, in this context, the desired outcome achievable by single dose administration of an aqueous pharmaceutical composition containing a therapeutically effective amount of active agents according to the invention.

[0018] By "active agent" or "active pharmaceutical ingredient" is meant any biologically active compound useful in the treatment and/or prevention of otitis externa and its sequalae, as well as associated pain and inflammation. In this respect, therefore, particularly preferred medicaments are antibiotics useful in the treatment or prevention of otitis externa in mammals. Depending on the severity of the condition and its cause, such antibiotics include, without limitation, amoxicillin (and other penicillins), ciprofloxacin (and other quinolone antibiotics, such as ofloxacin), clavulanate (and other beta-lactamase inhibitors), cefaclor (and other cephalosporins, such as cefixime), azithromycin (and other macrolide antibiotics, such as clarithromycin), sulfisoxazole (as well as other sulfa drugs, such as

sulfamethoxazole), chloramphenicol, thiamphenicol, and florfenicol.

[0019] Preferably, compositions of the invention will contain multiple agents useful in treating otitis externa including, without limitation, anti-fungal and anti-inflammatory compounds. Useful anti-inflammatory compounds for co-administration or use independent of antibiotic therapy include those that are sometimes less effective or well-tolerated in oral administration; e.g., non-steroidal anti-inflammatory drugs (NSAIDs), such as diclofenac, naproxen, ketoprofen, celecoxib, indomethacin, and pharmaceutically acceptable derivatives thereof. Steroidal compounds may be administered as an alternative or additive to an NSAID when clinically indicated (e.g., in chronic cases of otitis externa with pruritis), but are not required for use in the invention. Where present, the steroid may be betamethasone, betamethasone dipropionate, betamethasone acetate, fluocinonide, fluocinoline acetonide, hydrocortisone, methylprednisolone, mometasone furoate, clobetasol, beclomethasone, dexamethasone sodium phosphate, triamcinolone and pharmaceutically acceptable derivatives thereof.

[0020] In preferred embodiments, the pharmaceutically active agents provided will include an anti-fungal agent. Suitable anti-fungal agents primarily include those that act on the cell wall or membrane of the fungi, although others (e.g., intracellularly acting agents) may also be suitable when clinically indicated. In general, cell wall/membrane active anti-fungals include the allylamines, the azoles, the polyene antimicotics, and the echinocandins. Non- limiting specific examples include terbinafine, miconazole, ketoconazole, amphotericins, fluconazole, flucytosine, natamycin, amphotericin B, nystatin, cromolyn, lodoxamide, levocabastin, naphazolin, antazoline, pheniramimane and pharmaceutically acceptable derivatives thereof. Unless its use is contraindicated (e.g., for certain lupus patients), terbinafine is the presently preferred anti-fungal agent for use in the invention.

[0021] In some embodiments the pharmaceutically active agent may also include a local anesthetic or analgesic agent. Examples of suitable agents include benzocaine, benzyl benzoate, bupivacaine, calamine, chloroprocaine, chloroxylenol, cinchocaine, cocaine, dexivacaine, diamocaine, dibucaine, dyclonine, etidocaine, hexylcaine, ketamine,

levobupivacaine, lidocaine, menthol, mepivacaine, oxethazaine, phenol, pramoxine, prilocaine, amethocaine, tetracaine, proparacaine, propoxycaine, pyrrocaine, resorcinol, risocaine, rodocaine, ropivacaine, tetracaine, and pharmaceutically acceptable derivatives thereof. Due to the rapid action of the compositions of the invention in resolving treated otitis externa, use of such anesthetic or analgesics may be unnecessary.

[0022] In animals especially, otitis externa is often linked to a parasitic infestation, most often an otocariosis, or Otodectes cynotis (ear mites) infestation. Topical treatment with ear mites has often been accomplished with relatively long courses of topical insecticidal therapy, e.g., with a pyrethrin-containing composition. However, shorter courses of therapy have been more recently obtained with mectin and mycin compounds, e.g., avermectins (such as ivermectin and selamectin) and milbemycin, administered otically, by injection, or on the skin. If clinically indicated, such anti-parasiticidal compounds may be co-administered within, or as a separate adjunct to, the compositions of the invention. Further, where clinically indicated, anti-viral compounds, such as acyclovir, may be administered in lieu of, or as an adjunct to, antibiotic compounds.

[0023] Compositions administered according to the invention will be prepared in a pharmaceutically acceptable form. By "pharmaceutically acceptable" it is meant any inactive ingredients (e.g., a carrier, buffer, diluent or excipient, if any, used with the active ingredients of a composition) must be compatible with the other ingredients of the formulation and not deleterious to the recipient thereof.

[0024] The active compounds utilized in the invention may be formulated into therapeutic compositions as natural or salt forms. Pharmaceutically acceptable non-toxic salts include the base addition salts (formed with free carboxyl or other anionic groups) which may be derived from inorganic bases such as, for example, sodium, potassium, ammonium, calcium, or ferric hydroxides, and such organic bases as isopropylamine, trimethylamine, 2- ethylamino-ethanol, histidine, procaine, and the like. Such salts may also be formed as acid addition salts with any free cationic groups and will generally be formed with inorganic acids such as, for example, hydrochloric, sulfuric, or phosphoric acids, or organic acids such as acetic, citric, /?-toluenesulfonic, methanesulfonic acid, oxalic, tartaric, mandelic, and the like. Salts of the disclosure include amine salts formed by the protonation of an amino group with inorganic acids such as hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, phosphoric acid, and the like. Salts of the disclosure may also include amine salts formed by the protonation of an amino group with suitable organic acids, such as p-toluenesulfonic acid, acetic acid, and the like. Additional excipients which are contemplated for use in the practice of the disclosure are those available to those of ordinary skill in the art, for example, those found in the United States Pharmacopeia Vol. XXII and National Formulary Vol. XVII, U.S. Pharmacopeia Convention, Inc., Rockville, Md. (1989), the relevant contents of which is incorporated herein by reference. In addition, polymorphs, hydrates, and solvates of the active compounds are included in the disclosure.

[0025] Aqueous suspensions contain the active materials in admixture with excipients suitable for the manufacture of aqueous suspensions. Viscocity-enhancing/viscogenic or gelling agents are not required and may be excluded. If a suspending agent or solvent is utilized, its composition and concentration need not, and preferably will not, provide the suspension with a viscosity in excess of 5 cps. Penetration enhancers need not, and will preferably not, be present in the suspension, which is intended for treating the portion of the ear canal outside of the tympanic membrane.

[0026] The aqueous suspensions may also contain one or more preservatives, for example ethyl, or n-propyl, p-hydroxybenzoate. Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, suspending agent and one or more

preservatives.

[0027] The present disclosure provides methods for topically treating and preventing otitis externa through administration of multiple active agents, preferably at least two and most preferably at least three active agents, which are useful in prophylaxis or treatment of external ear infections, infestations and inflammation.

[0028] The terms "administration of and or "administering a" compound should be understood to mean providing one or more active compounds of the disclosure or a pharmaceutical composition containing such actives to the subject in need of treatment.

[0029] By "topical administration" is meant that a composition of the invention is applied to the external ear canal, i.e., on the outer ear side of the tympanic membrane (eardrum). The compositions of the invention do not contain gelling agents, methylcellulose or other adhesive elements, yet are sufficiently potent to ameliorate or resolve otitis externa through a single dose course of treatment.

[0030] Topical administration to the outer ear canal may be achieved by, for example, introducing the composition of the invention into the outer ear canal by any medically acceptable means, e.g., application of the carrier composition to the membrane by insertion of a needleless syringe, dropper or swab into the auditory canal. Administration is repeated as required to achieve the therapeutically effective dosage level for the antibiotic compound given. However, a particular advantage offered by the invention is that it enables

amelioration (substantial reduction of symptoms) or resolution (elimination of symptoms) of otitis externa with a course of treatment consisting of as little as one dose. For example, as demonstrated in Examples 2 and 3, 1.0 ml of an aqueous solution of a topical carrier composition delivered once resulted in clinical cures in 24 of 30 dogs receiving the aqueous formulation with the active pharmaceutical ingredients for an efficacy of 80.0%.

[0031] If the otitis externa proves to be unusually refractive to treatment, but the clinical symptoms of the condition are ameliorated after the first dose administered, a follow up dose can be delivered after a medically suitable period of time. Those of ordinary skill in the art will be familiar with, and readily able to select, dosing regimens suitable for following to treat a particular infection.

[0032] The following examples illustrate preparation and use of compositions of the invention to treat otitis externa in dogs. As demonstrated, the condition was resolved in most animals (24 out of 30 dogs or 80%) with a single dose course of treatment. For the negative control group, i.e., animals receiving the delivery vehicle only, clinical cures were observed in only 2 of 15 dogs or 13.3%. Animals who continued to show signs of the condition at day 7 following single dose treatment were withdrawn from the study for inefficacy and were considered treatment failures.

[0033] It will of course be appreciated that the invention may be utilized to treat otitis externa in any mammal, in whom the pharmaceutically acceptable, cellulose-free, non-gelled aqueous compositions of the invention will be applied topically to the outer ear canal in a dose sufficient to clinically ameliorate (significantly reduce symptoms to susceptibility to resolution with re-treatment, preferably a single dose re-treatment) or to resolve the treated condition. While physicians and veterinarians will of course be familiar with appropriate concentrations for dosing with individual active agents, the concentrations and dosing ranges expected to be efficacious in most clinical situations and species are 0.1 to 2.0% active pharmaceutical ingredient w/w, delivered in unit dosages of about 1 ml, depending on the clinician's judgment of the appropriate course of treatment and the strength of the dosage delivered.

[0034] The invention having been fully described, the following examples are intended to illustrate, not to limit, the scope of the invention, which is defined by the appended claims.

EXAMPLE 1

ANTIBIOTIC, ANTI-FUNGAL, ANTI-INFLAMMATORY-CONTAINING

COMPOSITION OF THE INVENTION

[0035] Sample pharmaceutically acceptable compositions for use in the methods of the invention to treat otitis externa in test subjects were prepared as follows.

EXAMPLE 2

TREATMENT OF OTITIS EXTERNA IN CANINES

[0037] Thirty dogs of varying breeds were divided into three treatment grou ps with two groups receiving the active formulation and one group receiving a negative control. All dogs were confirmed to have otitis externa, including bacterial infection, fungal infestation and inflammation, and were treated with a single dose by topical administration of 1 ml per ear of the active composition (IVP) of Example 1 or a control sample (CVP). The treated ears were evaluated for signs of otitis externa at days 7 and 14 following dosing. All personnel at the clinics were masked. Masking was achieved by placing the IVP and CVP in identical bottles. The IVP was labeled with code letters B or C, whi le the CVP was labeled with the code letter A.

The endpoint for effectiveness, i.e., a clinical cure was a clinical score improvement to 3 or less in the infected ear, or in the right ear if both ears were infected.

[0038] This example demonstrates the effectiveness and field safety of a combination otic formulation for the treatment of otitis externa in dogs. Two study groups (groups B & C) received the investigational veterinary product (IVP), which was a solution containing florienicol, terbinatlne and mometasone (Formulation 1), while a third study group (group A)

¹ Heated to 50 - 60 °C. received the control veterinary product (CVP), which was a solution identical to the IVP with the exception that the active ingredients were omitted,

[0039] At each of three study sites, ten dogs received the IVP and five dogs received the CVP, Thus, a total of 30 dogs received IVP and 15 dogs received CVP. All IVP cases were included in both efficacy and safety analyses.

[0040] Dogs enrolled in the study presented to the clinic with signs of otitis externa. On Day 0, a physical examination, including an aural and otoscopic exam, was conducted in order to verify an intact tympanic membrane, absence of foreign bodies and ear mites, and to assign a clinical score to the study ear based on erythema, exudate, swelling and ulceration. In order to be included in the study, the minimum clinical score had to be greater than or equal to 6, A hearing test was conducted, one ear swab was obtained for bacterial culture, one ear swab was obtained for fungal identification via cytology, and the ear was subsequently cleaned with saline. The dogs were dosed by administering 1.0 mi of the assigned IVP or CVP per infected ear. If both ears were infected, the right ear was designated as the study ear. For masking purposes, the IVP was identified as both ΓνΤ-Β and IVP-C, while the CVP was dentified as I VP- A.

[0041] At the first follow-up visit on Day 7 (± 2). an aural and otoscopic exam were conducted to evaluate irritation and to assign a clinical score. If there was no improvement in the Day 7 score as compared to the Day 0 score, the option was available to remove the dog from the study at the investigator's discretion.

[0042] At the final follow-up visit on Day 14 (± 2), a physical examination, including an aural and otoscopic exam, was conducted to evaluate initation and to assign a clinical score. A hearing test was also conducted. For a case to be considered a clinical cure, the final clinical score had to be less than or equal to 3. If clinical cure was not achieved, additional ear swabs were obtained for bacterial culture and fungal identification.

[0043] Based on clinical scores, clinical cures were obtained in 24 of 30 dogs receiving a single dose of IVP for an efficacy of 80.0%. Clinical cures were obtained in 2 of 15 dogs receiving CVP for an efficacy of 13.3%.

[0044] Effectiveness Assessment:

[0045] Clinical endpoints to be reached for effectiveness: Improvement in clinical score.

[0046] Clinical score measurement: Investigator evaluated the ear and assigned an objective clinical score.

[0047] Frequency of assessment: days 0, 7, and 14. [0048] Scoring system: Clinical scores were assigned based on a standard scoring system for each of the following clinical signs associated with otitis externa: erythema, exudate, swelling, and ulceration Each variable was scored on the following scale:

[0049] ERYTHEMA

[0050] 0 = none

[0051] 1 = mild: barely perceptible redness visible with otoscope

[0052] 2 = moderate: obvious redness visible with otoscope

[0053] 3 = severe: beet or cherry red or erythema extends into pinna

[0054] EXUDATE

[0055] 0 = none

[0056] 1 = mild: small amount visible with otoscope

[0057] 2 = moderate: small amount visible without otoscope

[0058] 3 = severe: extending out of ear canal and may be encrusted

[0059] SWELLING

[0060] 0 = none

[0061] 1 = mild: slight occlusion of the ear canal - can easily pass otoscope

[0062] 2 = moderate: some occlusion of the ear canal - difficulty passing otoscope

[0063] 3 = severe: canal almost completely occluded - very difficult to pass otoscope

[0064] ULCERATION

[0065] 0 = none

[0066] 1 = mild: localized area of abrasions

[0067] 2 = moderate: two or more areas of abrasions

[0068] 3 = severe: abrasions that are bleeding

[0069] Methods for computing and calculating the effect: Final clinical scores of 3 or less were considered treatment successes.

[0070] Additional Assessment: Hearing Evaluation

[0071] Clinical endpoints: ability or inability to hear was recorded as supportive information.

[0072] Measurement: Clinic personnel clapped their hands together in a location out of the dog's sight and observed if it turned toward where the noise originated.

[0073] Frequency of assessment: Days 0 and 14

[0074] Methods for computing and calculating effect: Day 0 results were compared to Day 14 results. [0075] Statistics: Descriptive statistics were performed to obtain percent efficacy.

[0076] Randomization method: Each animal was assigned in presentation order using randomization forms generated using the SAS statistical package. Each study site utilized a separate randomization form.

[0077] Animal selection and identification

[0078] Source: Dogs that presented to the clinic with otitis externa

[0079] Number: 45

[0080] Species: Canine

[0081] Age: > 8 weeks . Ages of IVP -treated dogs ranged from 7 months to 11.6 years old. Table 1 below includes study population distribution by age.

Table 1. Study Population Distribution by Age

[0082] Gender: Varied. Table 3 below includes study population distribution by gender.

[0083] Breed: Varied . Table 4 below includes study population distribution by breed.

[0084] Initial body weight: Body weights of IVP -treated dogs ranged from 9.8 to 121.9 pounds. Table 2 below includes study population distribution by weight.

Table 2. Study Population Distribution by Weight

Table 3. Study Population Distribution by Gender

Table 4. Study Population Distribution by Breed

Total 30 15 45

[0085] Physiological state: Varied

[0086] Inclusion criteria:

[0087] Eight weeks of age or older

[0088] Minimum clinical score of 6

[0089] Intact tympanic membrane

[0090] Exclusion criteria:

[0091] Clinical score of less than 6

[0092] Treatment with systemic or otic antimicrobials within the last 14 days

[0093] Treatment with parenteral or topical anti-inflammatory agents, including short- acting corticosteroids within the last 14 days

[0094] Treatment with parenteral or topical antihistamines within the last 14 days

[0095] Treatment with parenteral or topical long-acting corticosteroids within last 28 days

[0096] Concurrent Otodectes eynotis infections

[0097] Presence of foreign body in ear canal

10098| Post-inclusion removal criteria: No dogs were removed for serious adverse events or for failing to return for follow-up visits. There were eight dogs removed at Day 7 due to lack of improvement in the clinical score. Seven of these dogs received the CVP, while one dog received the IVP. All eight dogs were considered treatment failures.

[0099] Protocol Amendments and Deviations: There were no protocol amendments. The following protocol deviations occurred:

[0100] RON02: Day 14 culture result not obtained

[0101] RON07: Day 14 visit occurred on Day 17

[0102] SIF04: Day 14 visit occurred on Day 18

[0103] SIF15: Day 14 visit occurred on Day 17 EXAMPLE 3

EFFICACY OF AQUEOUS COMBINATION SOLUTION FORMULATION FOR THE

TREATMENT OF OTITIS EXTERNA

[0104] A total of 45 dogs were enrolled in the study, with 37 dogs completing the study through Day 14. Thirty (30) dogs received a single dose of I VP and 15 dogs received a single dose of CVP. One dog receiving 1VP (ROB02) and seven dogs receiving CVP withdrew from the study at Day 7 per protocol for inefficacy and were considered treatment failures (data included in the final analysis.) Surprisingly, clinical cures were obtained in 24 of 30 dogs after treatment with a single dose of the IVP formulation. A detailed summary of the study results is shown in Table 5.

Table 5. Efficacy of Combination Treatment Formulated as Aqueous Solution for Topical

Treatment of Otitis Externa

*FTC = failed to complete study - dog removed due to lack of improvement at Day 7 [0105] At the first treatment facility, 9 of 10 dogs treated with IVP completed the study, while 1 of the 5 dogs treated with CVP completed the study. One dog in the IVP group and 4 dogs in the CVP group dropped out at Day 7 for inefficacy and were considered treatment failures. At study completion, 9 of 10 IVP cases and 0 of 5 CVP cases had clinical scores of 3 or less.

[0106] At the second treatment facility, all 10 dogs treated with IVP completed the study, while 5 of the 5 dogs treated with CVP completed the study. At study completion, 6 of 10 IVP cases and 2 of 5 CVP cases had clinical scores of 3 or less.

[0107] At the third treatment facility, all 10 dogs treated with IVP completed the study, while 2 of the 5 dogs treated with CVP completed the study. Three dogs in the CVP group dropped out at Day 7 for inefficacy and were considered treatment failures. At study completion, 6 of 10 IVP cases and 0 of 5 CVP cases had clinical scores of 3 or less.

[0108] The data in Table 5 is indicative of the effectiveness of a single dose of IVP administered at a dose volume of 1.0 ml/ear for treating canine otitis externa complicated by susceptible strains of yeast and bacteria was 80.0% whereas the effectiveness of the negative control (IVP) was 13.3%.

[0109] The invention illustratively described herein may be practiced in the absence of any element or elements, limitation or limitations which is not specifically disclosed herein. The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention that in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention as defined by the appended claims.

[01 10| The contents of the articles, patents, and patent applications, and all other documents and electronically available information mentioned or cited herein, are hereby incorporated by reference in their entirety to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. Applicants reserve the right to physically incorporate into this application any and all materials and information from any such articles, patents, patent applications, or other documents. |01 1 11 The inventions illustratively described herein may suitably be practiced in the absence of any element or elements, limitation or limitations, not specifically disclosed herein. Thus, for example, the terms "comprising", "including," containing", etc. shall be read expansively and without limitation. Additionally, the terms and expressions employed herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the inventions embodied therein herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention.

[0112] The invention has been described broadly and generically herein. Each of the narrower species and subgeneric groupings falling within the generic disclosure also form part of the invention. This includes the generic description of the invention with a proviso or negative limitation removing any subject matter from the genus, regardless of whether or not the excised material is specifically recited herein. Other embodiments are set forth within the following claims.

[0113] In addition, where features or aspects of the invention are described in terms of Markush groups, those skilled in the art will recognize that the invention is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[01 14| The scope of our invention is defined by the following claims.

Claims

What is claimed is:

1. A method for treating or preventing otitis externa infection and sequelae, comprising administering, to a subject in need thereof, a single dose of an aqueous pharmaceutical dosage form, wherein the dosage form comprises a therapeutically effective amount of at least two active agents selected from the group consisting of antibiotics, anti-fungals, antiparasitics, anti-virals, non-steroidal anti-inflammatories, analgesics, anesthetics, and steroids.

2. The method of claim 1, wherein the administering is topical.

3. The method of claim 1, wherein the pharmaceutical dosage form is applied only to the outer ear canal.

4. The method of claim 1, wherein the pharmaceutical dosage form is a solution which does not contain a viscocity-enhancing or gelling agent.

5. The method of claim 1, wherein about 1 ml of the pharmaceutical dosage form is administered to the subject.

6. The method of claim 1, wherein one active agent in the pharmaceutical dosage form is an antibiotic.

7. The method of claim 1, wherein one active agent in the pharmaceutical dosage form is an anti-fungal.

8. The method of claim 1, wherein one active agent in the pharmaceutical dosage form is a non-steroidal anti-inflammatory drug (NSAID).

9. The method of claim 1, wherein one active agent in the pharmaceutical dosage form is a steroid.

10. The method of claim 6, wherein the antibiotic is selected from the group consisting of quinolone antibiotics, penicillin antibiotics, macrolide antibiotics, cephalosporin antibiotics, sulfa antibiotics, beta-lactamase inhibitors, and bacteriostatic antibiotics.

11. The method of claim 10, wherein the antibiotic comprises florfenicol.

12. The method of claim 7, wherein the anti-fungal is an allylamine anti-fungal agent.

13. The method of claim 12, wherein the allylamine is terbinafme.

14. The method of claim 9, wherein the steroid is mometasone furoate.

15. The method of claim 1, wherein the pharmaceutical dosage form comprises three active agents.

16. The method of claim 15, wherein the active agents are: (i) an antibiotic; (ii) an antifungal; and (iii) a steroid.

17. The method of claim 1, wherein the antibiotic is florfenicol, the anti-fungal is terbinafme, and the steroid is mometasone furoate.

18. The method of claim 17, wherein the florfenicol, terbinafme, and mometasone furoate are in aqueous solution.

19. The method of claim 18, wherein the terbinafme is present in a concentration of about 1 to 2.0% (w/w) of the solution.

20. The method of claim 18, wherein the mometasone furoate is present in a

concentration of about 0.1 to 0.5% (w/w) of the solution.

21. The method of claim 1 , wherein the subject is a mammal.

22. The method of claim 21 wherein the mammal is a dog.