WO2022008966A1

WO2022008966A1 - N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide composition for oral administration

Info

Publication number: WO2022008966A1
Application number: PCT/IB2020/060605
Authority: WO
Inventors: Reema Sinha; Sandeep Kumar Bansal; Dr. Shardendu Kumar MISHRA; Dr. Rahul KAUSHIK
Original assignee: Reema Sinha; Sandeep Kumar Bansal; Mishra Dr Shardendu Kumar; Kaushik Dr Rahul
Priority date: 2020-07-06
Filing date: 2020-11-11
Publication date: 2022-01-13

Abstract

The present invention relates to N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide composition for oral administration. Specifically, the invention relates to method of administration of N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide and the use thereof in the treatment of refractory epilepsy.

Description

N - [4 - (TRIFLUOROMETHOXY) BENZYLIDENE) NICOTINOHYDRAZIDE COMPOSITION FOR ORAL ADMINISTRATION.

PRIORITY:

This application claims the benefit of Indian complete application number 202011028643 dated 6^th July 2020 entitled, ‘N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide composition for oral administration’, the contents of which are incorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION:

BACKGROUND OF THE INVENTION:

Epilepsy is a central nervous system (neurological) disorder in which brain activity becomes abnormal, causing seizures or periods of unusual behavior, sensations, and sometimes loss of awareness.

Epilepsy isn't one disease or condition. There are many kinds of epilepsy with different symptoms and patterns.

Basic types of epilepsy based on the seizures are as follows -

• Generalized epilepsy

• Focal epilepsy

• Generalized and focal epilepsy

• Unknown if generalized or focal epilepsy

The treatment options depend upon the types of epilepsy.

Refractory epilepsy occurs when your antiepilepsy medicines are no longer controlling your seizures. Often the cause of refractory epilepsy is not known. The symptoms of refractory seizure include Convulsions, or shaking movements, Loss of consciousness, Confusion, Tongue biting, Lip smacking, Loss of bowel or bladder control, Uncontrolled eye movements, Staring into space, Falling, Muscle rigidness, tremors, or twitching, Odd behavior (such as screaming or yelling).

When medicines do not prevent a child's seizures, doctors may recommend a special diet, like the high-fat, low-carbohydrate ketogenic diet. Sometimes they recommend vagal nerve stimulation (VNS).

The treatment options for refractory seizures include antiepileptic drugs like Carbamazepine, Phenytoin, Gabapentin, Lamotrigine, Levetiracetam, Oxcarbazepine, Tiagabine, Topiramate and Zonisamide. If medicines aren't helping with the seizures, 2 options available are surgery and electrical stimulation.

Surgery may be very helpful if refractory partial epilepsy and the part of the brain where the seizures start can be found and safely removed. During the procedure, the healthcare provider will take out the part of your brain that's starting the seizures.

If the patient doesn’t want to have a brain surgery, the healthcare provider may suggest vagus nerve stimulation (VNS) with an implantable device. The device is placed under the skin in the chest. Wires are connected it to the vagus nerve in the neck. It sends a current to the nerve. With this device, there would be fewer seizures. It may also help lessen the severity of a seizure that has already started.

Several efforts are going on for newer treatment options for epilepsy, specifically refractory epilepsy.

A research paper Reema Sinha et al, Nicotinic acid hydrazones: a novel anticonvulsant pharmacophore, Medicinal Chemistry Research volume 20, pages 1499-1504(2011) explored and a series of aryl acid hydrazones of substituted aromatic acid hydrazides were synthesized and evaluated for anticonvulsant activity. Aryl acid hydrazones of Nicotinic acid hydrazide displayed excellent protection in maximal electroshock screen.

Pyridine-3 -carbohydrazide derivatives as potential anticonvulsants in generalized and partial seizures have been investigated in the research article Reema Sinha et al, In silico validation and structure activity relationship study of a series of Pyridine-3 - carbohydrazide derivatives as potential anticonvulsants in generalized and partial seizures, Central Nervous System agents in Medicinal Chemistry, 2013. The article explores various compounds as anti consul vants.

One of these compounds is N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide. Its preparation methodology is provided in the above mentioned article viz. Reema Sinha et al, In silico validation and structure activity relationship study of a series of Pyridine-3-carbohydrazide derivatives as potential anticonvulsants in generalized and partial seizures, Central Nervous System agents in Medicinal Chemistry, 2013. It is referred as RNH12 in the reference provided. The article concluded that RNH12 is the most potent analogue from nicotinic acid aryl hydrazones.

A better treatment option is still highly needed for treatment of refractory epilepsy and the proper administration of the drug to a patient in need thereof.

OBJECT OF THE INVENTION:

The main object of the invention is to provide N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide composition for oral administration.

Another object of the invention is to provide method of administration of N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide and the use thereof in the treatment of epilepsy, specifically refractory epilepsy.

Yet another object of the invention is to provide N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in proper dosing strength and administered in a suitable dosage form.

SUMMARY OF THE INVENTION:

The present invention relates to N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide composition for oral administration. Specifically, the invention relates to method of administration of N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide and the use thereof in the treatment of refractory epilepsy. In an embodiment of the present invention, there is provided a pharmaceutical composition comprising N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide and pharmaceutically acceptable inert excipients. Specifically, the composition comprises N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in the form of E-isomer.

In an aspect of the embodiment, the composition is administered orally.

In another aspect of the embodiment, the composition comprises N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in an amount between 400 mg to 1200 mg. In a further aspect of the embodiment, the composition is in the form of a solid dosage form. In a specific aspect of the embodiment, the solid dosage form is a tablet.

In one more aspect of the embodiment, the composition is used for the treatment of refractory epilepsy in a subject in need thereof.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 shows the Activity of N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in IHK model (Y7R2 Testing).

PET ATT, DESCRIPTION OF THE INVENTION:

The terms used in the specification are defined as follows.

As used herein, the terms "comprising" (and any form of comprising, such as "comprise", "comprises", and "comprised"), "having" (and any form of having, such as "have" and "has"), "including" (and any form of including, such as "includes" and "include"), or "containing" (and any form of containing, such as "contains" and "contain"), are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

A "subject," "individual," or "patient," is used interchangeably herein, which refers to a vertebrate, preferably a mammal, more preferably a human. Tissues, cells and their progeny of a biological entity obtained in vitro or cultured in vitro are also encompassed.

The use of the terms "a" and "an" and "the" and similar referents in the context of describing the elements (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" are to be construed as open-ended terms (i.e., meaning "including, but not limited to,") unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e g., "such as") provided herein, is intended merely to better illuminate the embodiments and does not pose a limitation on the scope of the claims unless otherwise stated. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

"Therapeutic effect" means any improvement in the condition of a subject, human or animal, treated according to the subject method, including obtaining a preventative or prophylactic effect, or any alleviation of the severity of signs and symptoms of a disease, disorder, or condition which can be detected by means of physical examination, laboratory or instrumental methods.

As used herein, the terms "about", "substantially", etc. are intended to allow some leeway in mathematical exactness to account for tolerances that are acceptable in the trade and to prevent any unconscientious violator from unduly taking advantage of the disclosure in which exact or absolute numerical values are given so as to help understand the invention.

As used herein, the phrase "in need thereof means that the animal or mammal has been identified as having a need for the particular method or treatment. In some embodiments, the identification can be by any means of diagnosis. In any of the methods and treatments described herein, the animal or mammal can be in need thereof. In some embodiments, the animal or mammal is in an environment or will be traveling to an environment in which a particular disease, disorder, or condition is prevalent.

As used herein, the terms "prevention" or "preventing" mean a reduction of the risk of acquiring a particular disease, condition, or disorder.

As used herein, the terms "treat," "treated," or "treating" mean both therapeutic treatment or prophylactic or preventative measures wherein the object is to prevent or slow down (lessen) an undesired physiological condition, disorder or disease, or obtain beneficial or desired clinical results. For purposes of this invention, beneficial or desired clinical results include, but are not limited to, alleviation of symptoms; diminishment of extent of condition, disorder or disease; stabilized (i.e., not worsening) state of condition, disorder or disease; delay in onset or slowing of condition, disorder or disease progression; amelioration of the condition, disorder or disease state or remission (whether partial or total), whether detectable or undetectable; an amelioration of at least one measurable physical parameter, not necessarily discernible by the patient; or enhancement or improvement of condition, disorder or disease.

The present invention will now be described with reference to the accompanying embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein. Rather, the embodiment is provided so that this disclosure will be thorough, and will fully convey the scope of the invention to those skilled in the art. In an embodiment of the present invention, there is provided a pharmaceutical composition comprising N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide and pharmaceutically acceptable inert excipients.

The pharmaceutically acceptable inert excipients comprise binders; diluents; lubricants; disintegrating agents; glidants; stabilizers; dissolution enhancing agents; pH modifiers or surface active agents.

Examples of binders include, potato starch; pregelatinized starch; modified starch; gelatin; wheat starch; corn starch; celluloses such as methyl cellulose, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropylmethyl cellulose, ethyl cellulose and sodium carboxy methyl cellulose; hydroxypropyl Starch, polymethacrylates; carbomers; natural gums such as acacia, alginic acid and guar gum; lactose (anhydrous, monohydrate, spray dried); liquid glucose; dextrin; sodium alginate; kaolin; povidone; syrup; polyethylene oxide; polyvinyl pyrrolidone; poly vinyl alcohol; poly-N-vinyl amide; polyethylene glycol; sucrose; polydextrose; gelatin; poly propylene glycol; tragacanth; ceratonia; glycerylbehenate; hydrogenated vegetable oil; zein; castor oil; paraffin; higher aliphatic alcohols; higher aliphatic acids; long chain fatty acids; fatty acid esters; agar; chitosan; maltodextrin; magnesium aluminum silicate; inulin and wax-like materials such as fatty alcohols, fatty acid esters, fatty acid glycerides, hydrogenated fats, hydrocarbons, stearic acid; Copovidone; dextrates, sunflower oil and stearyl alcohol.

Examples of diluents include microcrystalline cellulose; lactose, cellulose powdered, cellulose silicified, cellulose acetate, methyl cellulose, microcrystalline lactose; dibasic or tribasic calcium phosphate; saccharides; confectioner's sugar; compressible sugar; confectioner's sugar; sugar spheres; dextrates; dextrin; dextrose; fructose; maltose; sodium chloride; lactitol; maltodextrin; mannitol; sucrose; fructose; glycerylpalmitostearate; semithicone; Magnesium aluminum silicate; starch; pregelatinized starch; maltitol; xylitol; erythritol; isomalt; sorbitol; sulfobutylether b- cyclodextrin, polymethacrylates; talc; trehalose; ammonium alginate; calcium carbonate; ethyl cellulose; magnesium carbonate; magnesium oxide and calcium sulphate. The disintegrating agents include povidone, low- substituted hydroxypropyl cellulose; cross-linked polyvinyl pyrrolidone; cross-linked sodium carboxymethylcellulose; hydroxypropyl starch; sodium starch glycolate; sodium starch glycolate; sodium carboxymethylcellulose; carboxymethyl cellulose calcium; sodium carboxymethyl starch; ion-exchange resins such as polacrillin potassium; microcrystalline cellulose; starches and pregelatinized starch; formalin-casein; clays such as bentonite or veegum; guar gum; celluloses or cellulose derivatives; sodium alginate; calcium alginate; alginic acid; chitosan; magnesium aluminum silicate; colloidal silicon dioxide.

The lubricants may be selected from Mg, Al, Ca or Zn stearate; polyethylene glycol; polyvinyl alcohol; glycerylbehenate; glyceryl monostearate; Glycerylpalmitostearate; potassium benzoate; sodium benzoate; mineral oil; sodium stearylfumarate; palmitic acid, myristic acid; stearic acid; hydrogenated vegetable oil; hydrogenated castor oil; talc; hydrogenated soybean oil; stearyl alcohol; leucine; sodium lauryl sulfate; ethylene oxide polymers; poloxamer; octyldodecanol; Sodium stearylfumarate and colloidal silica.

The stabilizers may be selected from naturally occurring as well as synthetic phospholipids, their hydrogenated derivatives and mixtures thereof; organic acids like acetic acid, tartaric acid, citric acid, fumaric acid, lactic acid, and mixtures thereof sphingolipids and glycosphingolipids; physiological bile salts such as sodium cholate, sodium dehydrocholate, sodium deoxycholate, sodium glycocholate and sodium taurocholate; saturated and unsaturated fatty acids or fatty alcohols; ethoxylated fatty acids or fatty alcohols and their esters and ethers; alkylaryl-polyether alcohols such as tyloxapol; esters and ethers of sugars or sugar alcohols with fatty acids or fatty alcohols; acetylated or ethoxylated mono- and diglycerides; synthetic biodegradable polymers like block co-polymers of polyoxyethylene and polyoxypropyleneoxide; ethoxylatedsorbitanesters or sorbitanethers; amino acids, polypeptides and proteins such as gelatine and albumin; or combination thereof.

The glidants may be selected from magnesium trisilicate; powdered cellulose; starch; talc; tribasic calcium phosphate; calcium silicate; magnesium silicate; magnesium trisilicate; colloidal silicon dioxide; and silicon hydrogels. Dissolution enhancing agents may be selected from, but are not limited to, organic acids, inorganic acids or combination thereof. The organic acids include, but not limited to citric acid, fumaric acid, malic acid, maleic acid, tartaric acid, succinic acid, oxalic acid, aspartic acid, mandelic acid, glutaric acid, and glutamic acid. The inorganic acids include but not limited to hydrochloric acid, phosphoric acid, nitric acid, and sulfuric acid.

Other agents like pH modifiers such as acetic acid/alkali metal acetate, fumaric acid/alkali metal fumarate, succinic acid/alkali metal succinate, citric acid/alkali metal citrate, tartaric acid/alkali metal tartrate, lactic acid/alkali metal lactate, maleic acid/alkali metal maleate, methanesulphonic acid/alkali metal methanesulphonate, monoalkali metal phosphate, the alkali metal in each of the above salts being, for example, sodium or potassium, etc may also be added in the pharmaceutical composition.

The surface active agents used may be hydrophilic, hydrophobic or combination thereof. Hydrophilic surfactants may be either ionic or non-ionic.

Suitable hydrophilic ionic surfactants include, but are not limited to, alkylammonium salts; fusidic acid salts; fatty acid derivatives of amino acids, oligopeptides, and polypeptides; glyceride derivatives of amino acids, oligopeptides, and polypeptides; lecithins and hydrogenated lecithins; lysolecithins and hydrogenated lysolecithins; phospholipids and derivatives thereof; lysophospholipids and derivatives thereof; carnitine fatty acid ester salts; salts of alkylsulfates; fatty acid salts; sodium docusate; acyl lactylates; mono- and di-acetylated tartaric acid esters of mono- and di glycerides; succinylated mono- and di-glycerides; citric acid esters of mono- and di glycerides; ammonium lauryl sulfate, sodium lauryl sulfate, sodium myreth sulfate, dioctyl sodium sulfosuccinate, perfluorooctanesulfonate, perfluorobutanesulfonate, alkyl benzene sulfonates, alkyl aryl ether phosphate, alkyl ether phosphate, alkyl carboxylates like, fatty acid salts, sodium stearate, sodium lauroylsarcosinate, octenidinedihydrochloride, cetyltrimethylammonium bromide (CTAB) or hexadecyltrimethyl ammonium bromide, cetyltrimethylammonium chloride (CTAC), cetylpyridinium chloride (CPC), polyethoxylated tallow amine (POEA), benzalkonium chloride (BAC), benzethonium chloride (BZT), 5-Bromo-5-nitro-l,3- dioxane, dimethyldioctadecylammonium chloride, dioctadecyldimethylammonium bromide (DODAB), cocamidopropylbetaine, cocamidopropylhydroxysultaine and mixtures thereof.

Suitable hydrophilic non-ionic surfactants include alkylglucosides; alkylmaltosides; alkylthioglucosides; lauryl macrogolglycerides; polyoxyalkylene alkyl ethers such as polyethylene glycol alkyl ethers; polyoxyalkylenealkylphenols such as polyethylene glycol alkyl phenols; polyoxyalkylene alkyl phenol fatty acid esters such as polyethylene glycol fatty acids monoesters and polyethylene glycol fatty acids diesters; polyethylene glycol glycerol fatty acid esters; polyglycerol fatty acid esters; polyoxyalkylenesorbitan fatty acid esters such as polyethylene glycol sorbitan fatty acid esters; hydrophilic transesterification products of a polyol with at least one member of the group consisting of glycerides, vegetable oils, hydrogenated vegetable oils, fatty acids, and sterols; polyoxyethylene sterols, derivatives, and analogues thereof; poly oxy ethylated vitamins and derivatives thereof; polyoxyethylene- polyoxypropylene block copolymers; and mixtures thereof.

Suitable lipophilic surfactants include, but are not limited to fatty alcohols; glycerol fatty acid esters; acetylated glycerol fatty acid esters; lower alcohol fatty acids esters; propylene glycol fatty acid esters; sorbitan fatty acid esters; polyethylene glycol sorbitan fatty acid esters; sterols and sterol derivatives; polyoxyethylated sterols and sterol derivatives; polyethylene glycol alkyl ethers; sugar esters; sugar ethers; lactic acid derivatives of mono- and di-glycerides; hydrophobic transesterification products of a polyol with at least one member of the group consisting of glycerides, vegetable oils, hydrogenated vegetable oils, fatty acids and sterols; oil-soluble vitamins/vitamin derivatives; and mixtures thereof. Within this group, preferred lipophilic surfactants include glycerol fatty acid esters, propylene glycol fatty acid esters, and mixtures thereof, or are hydrophobic transesterification products of a polyol with at least one member of the group consisting of vegetable oils, hydrogenated vegetable oils, and triglycerides.

Isomerism is the phenomenon in which more than one compounds have the same chemical formula but different chemical structures. Chemical compounds that have identical chemical formulae but differ in properties and the arrangement of atoms in the molecule are called isomers. In the present case, the composition comprises N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in the form of E-isomer. The compound RNH12 prepared in Reema Sinha et al, In silico validation and structure activity relationship study of a series of Pyridine-3-carbohydrazide derivatives as potential anticonvulsants in generalized and partial seizures , Central Nervous System agents in Medicinal Chemistry, 2013 is E-isomer and the same is used for this invention.

Route of administration of a drug is significant for optimizing the effect of the drug on a particular site of action. In an aspect of the embodiment, the composition is administered orally. The oral administration route is preferred over the various other administration routes of drug delivery due to the many advantages it exhibits. These advantages include safety, good patient compliance, and ease of ingestion, pain avoidance, and versatility to accommodate various types of drugs.

In another aspect of the embodiment, the composition comprises N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in an amount between 400 mg to 1200 mg. Specifically, N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide is present in an amount of 400 mg, 420 mg, 450 mg, 475 mg, 500 mg, 525 mg, 550 mg or 575 mg or 600 mg or 625 mg or 650 mg or 675 mg or 685 mg or 700 mg or 725 mg or 750 mg or 775 mg or 800 mg or 825 mg or 850 mg or 875 mg or 900 mg or 925 mg of 950 mg or 950 mg or 975 mg or 1000 mg or 1050 mg or 1100 mg or 1150 mg or 1200 mg or any specific amount between 400 mg to 1200 mg.

In a further aspect of the embodiment, the composition is in the form of a solid dosage form. In a specific aspect of the embodiment, the solid dosage form is a tablet.

In one more aspect of the embodiment, the composition is used for the treatment of refractory epilepsy in a subject in need thereof. Specifically, N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide is administered in a dose range of 11 mg/kg body weight to 12 mg/kg body weight of the subject in need of the treatment. Specifically, N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide is administered in a dose of 11.42 mg/kg body weight of a subject in need thereof. The compositions according to the invention are prepared according to the methods available in the literature of tableting.

The present invention will now be described with reference to the accompanying examples of methodology and characterization used to establish the invention.

EXAMPLE 1

N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide (the compound) was evaluated by the National Institute of Neurological Diseases and Stroke (NINDS), USA Epilepsy Therapy Screening Program (ETSP) in rodent preclinical seizure models. The compound was evaluated for its ability to reduce the incidence of HPDs in the in vivo chronic Intrahippocampal Kainate (IHK) mouse model.

Methods -

Male adult C57BE6 mice were used (10 weeks old; Janvier, France). All animals were allowed free access to both food and water except when they were removed from their cages for the experimental procedure. All rats were housed, fed, and handled in a manner consistent with the recommendations in the National Research Council publication, "Guide for the Care and Use of Laboratory Animals." No insecticides capable of altering hepatic drug metabolism enzymes were used in the animal facilities. All animals were euthanized in accordance with the Institute of Laboratory Resources policies on the humane care of laboratory animals.

All protocols involving the care and use of animals have been approved by the Institutional Animal Care and Use Committee at the University of Utah.

The compound was administered perorally in a volume of 0.01 ml/g body weight in mice. Intrahippocampal Kainate Mouse Model IHK studies are conducted by SynapCell (France). Experiments are performed on adult, male C57BE6 mice of at least 10 weeks of age. Surgery is performed under general anesthesia using a mixture of isoflurane (2-3%) in oxygen.

Animals are placed in a stereotactic frame in a flat skull position and injected using the protocol. A stainless steel cannula connected to a micro-syringe (Hamilton) via PE20 tubing containing distilled water is filled with a 1 nmol KA solution (Sigma) in 100 nL 0.9% sterile NaCl and positioned in the right dorsal hippocampus. Mice receive the KA solution using a micro-pump. After KA injection, all mice are implanted with a bipolar electrode into the injected hippocampus and a reference electrode over the cerebellum. After surgery, mice are housed in individual cages with food and water ad libitum and kept under a 12/12h light-dark controlled cycle (lights on between 8:00 am and 8:00 pm, room temperature at 21 ± 3°C). All experiments are performed during the light hours of the cycle. At the end of the surgery, animals receive a single injection of buprenorphine (O.lmg/kg). The animals are allowed to recover for four weeks prior to evaluation in the screening protocol.

The electroencephalogram (EEG) is recorded in freely moving animals placed in individual plexiglass cages (15 x 15 x 25 cm) in a Faraday cage using a digital acquisition computed-based system (Coherence 3NT, Deltamed, France, or SystemPlus Evolution, Micromed, France). A referential setup is used in which hippocampal electrodes are referenced with the electrode placed over the cerebellum. Offline analysis is performed using Coherence software (Deltamed, France) to detect HPDs i.e. high amplitude hippocampal discharges lasting at least 5 seconds and separated by at least 1 second.

Doses are selected for testing in this model using the 6 Hz 44 mA ED50. TD50 values may also influence dose selection. For all acute studies, drug conditions are counter balanced in MTLE mice over a two-week period using a Latin square dosing protocol. From four weeks after KA injection, 10 MTLE mice are injected with drugs in a random order (two injections per week). Animals are used as their own controls. Digital EEG recordings are performed on freely moving animals for 20 minutes pre injection (reference period) and 90 minutes post-injection.

Data are analyzed for the period of 10 minutes before and 10 minutes after TPE (e.g., from 6 Hz 44 mA studies) of the investigational compound. The effects of the injected compound are compared to the reference period. Any accompanying effect on animal behavior is noted. Data are presented as the number of HPDs during the analyzed 20- minute period (10 minutes before and 10 minutes after TPE of compound) for each MTLE mouse, group mean number of HPDs, and by percent of baseline HPD values. Results

In the chronic mouse IHK model of mesial temporal lobe epilepsy, male mice are treated with a unilateral intrahippocampal infusion of the excitotoxin kainic acid (KA) to induce spontaneous hippocampal paroxysmal discharges (HPDs) two to three weeks post-infusion.

This result in superimposed rhythmic depolarizations that initiate bursts of action potentials similar to those recorded in human tissue from temporal lobe epilepsy patients.

The compound significantly decreased HPDs for the 20-minute period surrounding the time of peak effect (TPE), as determined in the 6 Hz 44 mA assay (see Table 1 and associated Figure 1- significance assessed using a paired t test).

A total of seven mice were evaluated for treatment condition (130 mg/kg, p.o.) at 30 minutes post-drug administration, with the mean baseline HPD count determined prior to drug administration. HPD counts were 7.14 % ± 7.14 of baseline levels in mice that were administered the compound.

SEfvl - standard error of the mean; TPE - time of peak effect ^***p<0.001 vs baseline (paired t-tests

Table 1: Activity of the compound in IHK model (Y7R2 Testing)

EXAMPLE 2 Composition according to the invention

Manufacturing process

The tablet dosage form according to the invention is prepared using the above ingredients by wet granulation method.

Claims

We claim:

1. A pharmaceutical composition comprising N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide and pharmaceutically acceptable inert excipients.

2. The composition according to claim 1, wherein the composition is administered orally.

3. The composition according to claim 1, wherein the composition comprises N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in an amount between 400 mg to 1200 mg.

4. The composition according to claim 1, wherein the composition is in the form of a solid dosage form.

5. The composition according to claim 4, wherein the solid dosage form is a tablet.

6. The composition according to claim 1, wherein the composition is used for the treatment of refractory epilepsy in a subject in need thereof.

7. The composition according to claim 1, wherein the composition comprises N - [4 - (trifluoromethoxy) benzylidene) nicotinohydrazide in the form of E-isomer.