HK1263278A1 - Triple combination product of histamine-3 receptor inverse agonists, acetylcholinesterase inhibitors and nmda receptor antagonist - Google Patents

Description

Triple combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist

Technical Field

The present invention relates to histamine-3 receptors (H) in combination with or as an adjunct to acetylcholinesterase inhibitors (AChEI) and N-methyl-D-aspartate (NMDA) receptor antagonists₃R) an inverse agonist or a pharmaceutically acceptable salt thereof. The invention also relates to the use of such a combination and of a pharmaceutical composition containing said combination for the treatment of cognitive disorders.

Background

Alzheimer's Disease (AD) is the most common cause of dementia worldwide. The number of cases of AD predicted in the past and in the next decades is exponentially increasing and is expected to put great pressure on the society and healthcare systems of both developed and developing economies as well. AD also places a significant emotional and economic burden on the patient's families and society.

The current list of cognitive enhancing drugs approved for AD is not long and historically there has been a constant interest in acetylcholinesterase inhibitors (donepezil, rivastigmine and galantamine). These drugs act by targeting the enzyme acetylcholinesterase (AChE) to inhibit the hydrolysis of acetylcholine (ACh) to acetate and choline. Increasing levels of ACh in the synapse can stimulate cholinergic receptors and promote memory function. Although acetylcholinesterase inhibitors (AChEI) can temporarily delay the progression of cognitive decline in AD, their effects are moderate. ACh is present in both the central and peripheral nervous systems, and AChEI produces a number of adverse side effects, such as gastrointestinal disturbances, bradycardia and excessive salivation, which are associated with effects on peripheral muscarinic cholinergic receptors (Expert Opinion on drug safety,3,2004, 425-. The limitation of AChE inhibitor class drugs is their poor tolerability, their inability to sustain efficacy, and their need for constant dose titers as the disease progresses (Cochrane Database Systematic Reviews,2006, CD005593), which results in significant patient non-compliance. The incidence and severity of these side effects increases with increasing dose and is generally more pronounced at the beginning of treatment or after increasing dose. Therefore, there is an unmet need for alternative therapies for the treatment of cognitive disorders.

H₃R is a G protein-coupled receptor (GPCR), expressed primarily in the cortex, hippocampus, and anterior part of the striatum. H₃R functions as both an autoreceptor (autoreceptor) and a heteroreceptor (heteroreceptor). It regulates the synthesis and release of a variety of neurotransmitters that play important roles in cognitive, emotional, and sensory gating. Preliminary literature reports indicate that H₃R antagonists may have promising utility in the treatment of a variety of CNS disorders, including AD, schizophrenia, attention-deficit hyperactivity disorder (ADHD), epilepsy, narcolepsy, neuropathic pain, and metabolic disorders. Antagonism of this receptor by a variety of investigational compounds has been shown to improve learning and memory in animal models.

Due to blocking of H₃R modulates histaminergic and cholinergic activity, and H is expected₃The R inverse agonist complements and/or enhances the cognitive function of AChEI. This may in turn help to reduce side effects, while having better patient compliance and thus may be administered for a long period of time.

The glutamatergic system is also involved in learning and memory and is a target for the treatment of alzheimer's disease. Memantine, another approved treatment for alzheimer's disease, acts on the glutamatergic system by inhibiting the NMDA receptor under overstimulatory conditions. It can protect glutamate neurons from excessive glutamate stimulation, while increasing signal-to-noise ratio. Glutamate neurons are known to have synaptic connections on cholinergic neurons in brain regions associated with learning and memory.

Since the cause and progression of dementia depends on different mechanisms, it may be advantageous to treat AD using combinations of drugs that work with different mechanisms. Currently approved therapies for AD include the combination of the acetylcholinesterase inhibitor donepezil and the NMDA receptor antagonist memantine. However, there is still a need for new drugs/combinations to treat patients with AD.

The compound of the invention is H₃R is reversely excitedAn animal agent which has high affinity and very high selectivity for closely related receptor subtypes and improves learning and memory in animals. H as referred to herein₃R inverse agonist compounds are described in US9079888B2, which is incorporated herein by reference. The preparation of these compounds is given in the above mentioned patents.

Since the treatment of AD is chronic in nature, there is an extremely desirous unmet medical need for better and safer treatment options. The therapeutic strategy urgently sought by AD patients is to achieve improvements by aiding existing treatments, which brings additional relief to the patient, reduces the burden on the caregiver, and enables the patient to enjoy better quality of life without the need for institutional care and/or hospitalization.

The invention provides H₃An R inverse agonist compound or a pharmaceutically acceptable salt thereof for use in combination therapy with an AChEI and NMDA receptor antagonist to enhance cognitive function in a patient. The present invention is based on the following unusual findings: having H₃The combination of a compound having R inverse agonist activity, a compound acting as AChEI (e.g., donepezil), and a compound acting as NMDA receptor antagonist (e.g., memantine) shows a synergistic effect in its pharmacological activity. When levels are too high, memantine acts by blocking glutamatergic neurotransmission in the brain. Histamine regulates the release of glutamate from cortical striatal nerve endings. Therefore, H was never expected₃The combination of R inverse agonist + donepezil + memantine produces a synergistic pro-cognitive effect. However, surprisingly, H₃The combination of R inverse agonist + AChEI + NMDA receptor antagonist (triple combination) shows a synergistic effect in animal models and also increases the level of acetylcholine, a neurotransmitter playing an important role in cognitive improvement. Based on these results, H can be inferred₃Such combined administration and/or co-treatment of R inverse agonist + AChEI + NMDA receptor antagonist may produce beneficial effects to improve therapeutic efficacy in humans. Further, H of the present invention₃The R inverse agonist compounds or pharmaceutically acceptable salts thereof enhance the effects of ache and NMDA receptor antagonists in the treatment of cognitive disorders.

Disclosure of Invention

It is an object of the present invention to provide improved combination therapies for the treatment of cognitive disorders such as Alzheimer's disease, schizophrenia, Parkinson's disease, lewy body dementia, vascular dementia, frontotemporal dementia, Down syndrome or Tourette's syndrome.

In a first aspect, the present invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another aspect, the invention relates to a combination of a histamine-3 inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the histamine-3 receptor inverse agonist is selected from the group consisting of:

n- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide;

n- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide; and

n- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide;

or a pharmaceutically acceptable salt thereof.

In another aspect, the invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the histamine-3 receptor inverse agonist is N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof.

In another aspect, the invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the histamine-3 receptor inverse agonist is N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof.

In another aspect, the invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the histamine-3 receptor inverse agonist is N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof.

In another aspect, the invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the acetylcholinesterase inhibitor is selected from donepezil, galantamine and rivastigmine or their pharmaceutically acceptable salts.

In another aspect, the invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the NMDA receptor antagonist is memantine, or a pharmaceutically acceptable salt thereof.

In another aspect, the present invention relates to a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, donepezil and memantine, or a pharmaceutically acceptable salt thereof.

In another aspect, the present invention relates to a combination of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, donepezil and memantine, or a pharmaceutically acceptable salt thereof.

In another aspect, the present invention relates to a combination of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, donepezil and memantine, or pharmaceutically acceptable salts thereof.

In another aspect, the invention relates to said combination for use in the treatment of cognitive disorders.

In another aspect, the invention relates to said combination for use in the treatment of cognitive disorders, such as alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome or tourette's syndrome.

In another aspect, the invention relates to a method of treating a cognitive disorder (e.g. alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome or tourette's syndrome) comprising administering a therapeutically effective amount of said combination to a patient in need thereof.

In another aspect, the invention relates to histamine-3 receptor inverse agonists for use in the adjunctive treatment of cognitive disorders (e.g., alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome, or tourette's syndrome) in patients treated with acetylcholinesterase inhibitors and NMDA receptor antagonists.

In another aspect, the present invention relates to the compound N- [4- (1-cyclobutyl-piperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, for use in the adjunctive treatment of cognitive disorders (e.g. alzheimer's disease, schizophrenia, parkinson's disease, lewy body dementia, vascular dementia, frontotemporal dementia, down's syndrome or tourette's syndrome) in a patient being treated with donepezil and memantine.

In another aspect, the present invention relates to the compound N- [4- (1-cyclobutyl-piperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, for use in combination or adjunctive treatment of cognitive disorders such as alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome or tourette's syndrome with acetylcholinesterase inhibitors and NMDA receptor antagonists.

In another aspect, the present invention relates to a method for the treatment of cognitive disorders comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, in combination with or as an adjunct to donepezil or a pharmaceutically acceptable salt thereof and memantine or a pharmaceutically acceptable salt thereof.

In another aspect, the invention relates to the use of a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist for the treatment of cognitive disorders (e.g. alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome or tourette's syndrome).

In another aspect, the invention relates to the use of N- [4- (1-cyclobutyl-piperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, donepezil and memantine, or pharmaceutically acceptable salts thereof, for the treatment of cognitive disorders such as alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome or tourette's syndrome.

In another aspect, the present invention relates to a pharmaceutical composition comprising a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist and a pharmaceutically acceptable excipient or a combination thereof.

In another aspect, the present invention relates to a pharmaceutical composition comprising N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, donepezil and memantine, or pharmaceutically acceptable salts thereof, and a pharmaceutically acceptable excipient, or a combination thereof.

In another aspect, the present invention relates to a pharmaceutical composition comprising a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist, or pharmaceutically acceptable salts thereof, and pharmaceutically acceptable excipients, or combinations thereof, for use in the treatment of cognitive disorders, such as alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome, or tourette's syndrome.

Brief Description of Drawings

Figure 1a depicts the results of the effect of co-treatment of compound 1 with donepezil and memantine on cognitive enhancing properties using an object recognition task model.

Figure 1b depicts the results of the effect of co-treatment of compound 3 with donepezil and memantine on cognitive enhancing properties using an object recognition task model.

Figure 2 depicts the effect of compound 1 in combination with donepezil and memantine on extracellular acetylcholine levels in the medial prefrontal cortex of male Wistar rats.

Figure 3 depicts the effect of compound 2 in combination with donepezil and memantine on extracellular acetylcholine levels in the medial prefrontal cortex of male Wistar rats.

Figure 4 depicts the effect of compound 3 in combination with donepezil and memantine on extracellular acetylcholine levels in the medial prefrontal cortex of male Wistar rats.

Figure 5 depicts the effect of compound 1 in combination with donepezil and memantine on theta levels induced in the dorsal hippocampus of anesthetized male Wistar rats.

Detailed Description

Unless otherwise indicated, the following terms used in the specification and claims have the following meanings:

the term "histamine-3 receptor inverse agonist" as used herein refers to a ligand or drug that binds to the constitutively active histamine-3 receptor, stabilizing them and thereby reducing activity (negative intrinsic activity). Which block or inhibit agonist pair H₃Receptor function/binding and exert the opposite pharmacological effects of receptor agonists.

Examples of histamine-3 receptor inverse agonists include:

n- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide;

n- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide; and

n- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide;

or a pharmaceutically acceptable salt thereof.

Examples of pharmaceutically acceptable salts of the above compounds include, but are not limited to, N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride; 2- (morpholin-4-yl) acetamide tartrate, N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -N- [4- (morpholin-4-yl) acetamide tartrate; and N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate.

The term "acetylcholinesterase inhibitor" as used herein is a chemical or drug that inhibits the breakdown of acetylcholine by acetylcholinesterase, thereby increasing both the level and duration of action of the neurotransmitter acetylcholine. Examples of acetylcholinesterase inhibitors are donepezil, rivastigmine and galantamine. Preferably, the acetylcholinesterase inhibitor is donepezil and rivastigmine. More preferably, the acetylcholinesterase inhibitor is donepezil.

Donepezil is a drug approved for the treatment of mild, moderate and severe dementia of alzheimer's disease. Donepezil is a reversible inhibitor of acetylcholinesterase, available under the trade name donepezilSold as the hydrochloride salt.

RivastigmineIs a drug approved for the treatment of mild, moderate and severe dementia of alzheimer's disease. Rivastigmine is a reversible cholinesterase inhibitor, sold under the trade name RivastigmineAnd ExelonSold as the tartrate salt.

Galantamine is a drug approved for the treatment of mild, moderate and severe dementia of alzheimer's disease. Galantamine is a reversible competitive acetylcholinesterase inhibitor, sold asSold as the hydrobromide salt.

The term "NMDA receptor antagonist" as used herein refers to a class of compounds that act on the glutamatergic system by inhibiting the NMDA receptor. An example of an NMDA receptor antagonist is memantine. Memantine is a drug approved for the treatment of moderate to severe dementia with alzheimer's disease. Memantine is an NMDA receptor antagonist, available under the trade name MemantineAnd NamendaSold as the hydrochloride salt.

The combination of memantine and donepezil is approved for the treatment of moderate to severe dementia of alzheimer's disease and is available under the trade name Namzaric^TMSold as memantine hydrochloride and donepezil hydrochloride.

The phrase "therapeutically effective amount" is defined as the following amount of a compound of the invention: (i) treating a particular disease, condition, or disorder, (ii) eliminating one or more symptoms of a particular disease, condition, or disorder, and (iii) delaying the onset of one or more symptoms of a particular disease, condition, or disorder described herein.

The term "pharmaceutically acceptable salt" as used herein refers to salts of the active compounds and is prepared by reaction with a suitable organic or inorganic acid or acid derivative, depending on the particular substituents found on the compounds described herein.

The term "patient" as used herein refers to an animal. Preferably, the term "patient" refers to a mammal. The term mammal includes animals such as mice, rats, dogs, rabbits, pigs, monkeys, horses, and humans. More preferably, the patient is a human.

The term "alzheimer's disease" as used herein refers to dementia that causes memory, thinking and behavior problems. The alzheimer's disease may be mild to moderate to severe alzheimer's disease.

Compound 1 as used herein is N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, which has the following chemical structure:

compound 2 as used herein is N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, having the following chemical structure:

compound 3 as used herein is N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, having the following chemical structure:

the term "treatment" as used herein refers to any treatment of a disease in a mammal, including: (a) slowing or arresting the development of clinical symptoms; and/or (b) causing regression of clinical symptoms.

The term "compound for use" as used herein includes any one or more of the following: (1) use of a compound, (2) method of use of a compound, (3) use in therapy, (4) use for the manufacture of a pharmaceutical composition/medicament for therapy, or (5) method of treatment/therapy/prevention/reduction/inhibition comprising administering to a subject in need thereof an effective amount of an active compound.

The term "cognitive disorders" as used herein refers to a group of mental health disorders that primarily affect learning, memory, perception and problem resolution, including amnesia, dementia and delirium. Cognitive disorders may be caused by a disease, condition, disorder, or toxicity. Examples of cognitive disorders include, but are not limited to, alzheimer's disease, schizophrenia, parkinson's disease, Lewy Body Dementia (LBD), vascular dementia, frontotemporal dementia (FTD), down's syndrome, or tourette's syndrome. Preferably, the cognitive disorder is alzheimer's disease.

The term "adjuvant" or "adjuvant therapy" as used herein refers to an additional treatment of a patient who has received at least one other treatment for cognitive disorders. Drugs used as adjunctive therapy are administered to patients to make the initial therapy work better.

Detailed description of the preferred embodiments

The present invention encompasses all combinations described herein without limitation, however, some preferred aspects and elements of the invention are discussed herein in the form of the following embodiments.

In one embodiment, the present invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the histamine-3 receptor inverse agonist is N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride.

In another embodiment, the invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the histamine-3 receptor inverse agonist is N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate.

In another embodiment, the invention relates to a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the histamine-3 receptor inverse agonist is N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, rivastigmine and memantine, or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, galantamine and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, rivastigmine and memantine, or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, galantamine and memantine or pharmaceutically acceptable salts thereof.

In another embodiment, the present invention relates to a combination of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, rivastigmine and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to a combination of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, galantamine and memantine or pharmaceutically acceptable salts thereof.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, donepezil hydrochloride, and memantine hydrochloride.

In another embodiment, the invention relates to a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, rivastigmine tartrate, and memantine hydrochloride.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, galantamine hydrobromide and memantine hydrochloride.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, donepezil hydrochloride, and memantine hydrochloride.

In another embodiment, the invention relates to a combination of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, rivastigmine tartrate and memantine hydrochloride.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, galantamine hydrobromide and memantine hydrochloride.

In another embodiment, the present invention relates to a combination of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, donepezil hydrochloride, and memantine hydrochloride.

In another embodiment, the invention relates to a combination of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, rivastigmine tartrate and memantine hydrochloride.

In another embodiment, the present invention relates to a combination of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate, galantamine hydrobromide and memantine hydrochloride.

In another embodiment, the present invention provides a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist that is more effective than the combination of a histamine-3 receptor inverse agonist and an acetylcholinesterase inhibitor, an acetylcholinesterase inhibitor and an NMDA receptor antagonist, or a histamine-3 receptor inverse agonist and an NMDA receptor antagonist.

In another embodiment, the present invention provides a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor, and an NMDA receptor antagonist that is more effective than the histamine-3 receptor inverse agonist alone, the acetylcholinesterase inhibitor alone, and the NMDA receptor antagonist alone.

In another embodiment, the present invention provides a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, donepezil hydrochloride, and memantine hydrochloride that is more effective than N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride and donepezil hydrochloride, and memantine hydrochloride, or N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, and memantine hydrochloride.

In another embodiment, the present invention provides a combination of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, donepezil hydrochloride, and memantine hydrochloride that is more effective than N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, donepezil hydrochloride, and memantine hydrochloride alone.

In another embodiment, pharmaceutically acceptable salts of the histamine-3 receptor inverse agonist include, but are not limited to, dihydrochloride, oxalate, succinate, tartrate, and the like. Preferably, the pharmaceutically acceptable salts are dihydrochloride and tartrate. More preferably, the pharmaceutically acceptable salt is the dihydrochloride salt.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of said combination.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclobutyl-piperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof, an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof, an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, in combination with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, in combination with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, in combination with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride in combination with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate in combination with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate in combination with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride in combination with donepezil or a pharmaceutically acceptable salt thereof and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride in combination with donepezil hydrochloride and memantine hydrochloride.

In another embodiment, the present invention relates to a combination of N- [4- (1-cyclobutyl-piperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, an acetylcholinesterase inhibitor and an NMDA receptor antagonist for use in the treatment of Alzheimer's disease.

In another aspect, the invention relates to N- [4- (1-cyclobutyl-piperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, for use in the adjunctive treatment of alzheimer's disease in a patient being treated with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another aspect, the invention relates to N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, for use in the adjunctive treatment of alzheimer's disease in a patient being treated with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another aspect, the invention relates to N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, for use in the adjunctive treatment of alzheimer's disease in patients being treated with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the invention relates to N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride for use as an adjunct treatment for alzheimer's disease in a patient being treated with donepezil and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate for use as adjunct treatment for alzheimer's disease in a patient being treated with donepezil and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate for use in the adjunctive treatment of alzheimer's disease in a patient being treated with donepezil and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the invention relates to the use of a combination of a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist in the manufacture of a medicament for the treatment of alzheimer's disease.

In another embodiment, the invention relates to the use of a histamine-3 receptor inverse agonist in the manufacture of a medicament for use in the treatment of alzheimer's disease in combination with an acetylcholinesterase inhibitor and an NMDA receptor antagonist.

In another embodiment, the invention relates to the use of a histamine-3 receptor inverse agonist in the manufacture of a medicament for the treatment of alzheimer's disease as an adjunct to acetylcholinesterase inhibitors and NMDA receptor antagonists.

In another embodiment, the invention relates to the use of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, for the preparation of a medicament for the treatment of alzheimer's disease in combination with donepezil or a pharmaceutically acceptable salt thereof and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the present invention relates to the use of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride for the preparation of a medicament for the treatment of alzheimer's disease in combination with donepezil or a pharmaceutically acceptable salt thereof and memantine or a pharmaceutically acceptable salt thereof.

In another embodiment, the invention relates to the use of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride for the preparation of a medicament for the treatment of alzheimer's disease in combination with donepezil hydrochloride and memantine hydrochloride.

In another embodiment, the invention relates to a histamine-3 receptor inverse agonist, which is conjugated to Namzaric^TMThe combination is useful for the treatment of alzheimer's disease.

In another embodiment, the invention relates to a method of treating alzheimer's disease comprising administering to a patient in need thereof a therapeutically effective amount of a compound of formula i and a pharmaceutically acceptable carrier^TMA combined histamine-3 receptor inverse agonist.

In another embodiment, the invention relates to a combination for use in the treatment of alzheimer's disease, wherein alzheimer's disease is mild alzheimer's disease.

In another embodiment, the invention relates to a combination for use in the treatment of alzheimer's disease, wherein alzheimer's disease is moderate alzheimer's disease.

In another embodiment, the invention relates to a combination for use in the treatment of alzheimer's disease, wherein alzheimer's disease is severe alzheimer's disease.

In another embodiment, the invention relates to a combination wherein the active ingredients can be administered to a patient simultaneously or separately.

In another aspect, the active ingredients of the COMBINATION OF THE INVENTION are generally administered by formulating the active ingredients into pharmaceutical compositions according to standard pharmaceutical practice.

In another aspect, the active ingredients of the combination of the invention may be administered by oral, nasal, topical, dermal or parenteral routes.

In another aspect, the active ingredients of the COMBINATION OF THE INVENTION can be administered by the same or different routes of administration. For example, the histamine-3 receptor inverse agonist of the present invention may be administered orally, the acetylcholinesterase inhibitor may be administered transdermally, and the NMDA receptor antagonist may be administered topically.

The pharmaceutical compositions of the present invention may be formulated in a conventional manner using one or more pharmaceutically acceptable excipients. Pharmaceutically acceptable excipients are diluents, disintegrants, binders, lubricants, glidants, polymers, coating agents, solvents, co-solvents, preservatives, wetting agents, thickeners, antifoams, sweeteners, flavoring agents, antioxidants, colorants, solubilizers, plasticizers, dispersants, etc. The excipient is selected from microcrystalline cellulose, mannitol, lactose, pregelatinized starch, sodium starch glycolate, corn starch or derivatives thereof, povidone, crospovidone, calcium stearate, glyceryl monostearate, glyceryl palmitostearate, talc, colloidal silicon dioxide, magnesium stearate, sodium lauryl sulfate, sodium stearyl fumarate, zinc stearate, stearic acid or hydrogenated vegetable oils, gum arabic, magnesium oxide, glucose, fats, waxes, natural or hardened oils, water, physiological sodium chloride solutions or alcohols (e.g., ethanol, propanol or glycerol), sugar solutions (e.g., glucose solutions or mannitol solutions), and the like or mixtures of various excipients.

In another aspect, the active compounds of the present invention may be formulated as pills, tablets, coated tablets, capsules, powders, granules, pellets, patches, implants, films, liquids, semisolids, gels, aerosols, emulsions, elixirs, and the like. Such pharmaceutical compositions and methods for their preparation are well known in the art.

In another aspect, the pharmaceutical compositions of the present invention contain 1 to 90%, 5 to 75%, and 10 to 60% by weight of a compound of the present invention or a pharmaceutically acceptable salt thereof. The amount of active compound or a pharmaceutically acceptable salt thereof in the pharmaceutical composition may be from about 0.1mg to about 100mg or from about 0.1mg to about 60mg or from about 0.1mg to about 30mg or any range falling within the broader range of 0.1mg to 100 mg.

In another aspect, the pharmaceutical compositions of the combination of the invention may be conventional formulations, such as immediate release formulations, modified release formulations such as sustained release formulations, delayed release formulations and extended release formulations, or new delivery systems, such as orally disintegrating formulations and transdermal patches.

The dosage of the active compound may vary depending on factors such as the age and weight of the patient, the nature, the route of administration and the severity of the disease to be treated. Thus, any reference to a pharmacologically effective amount of compounds 1, 2 and 3 refers to the factors described above.

In another aspect, the histamine-3 receptor inverse agonist may be co-administered with an acetylcholinesterase inhibitor and an NMDA receptor antagonist in a daily dose of 0.1mg to 100 mg; e.g. 0.1, 0.5, 0.75, 1, 1.5, 3, 5, 6, 10, 20, 25, 30, 50, 75 and 100mg, preferably a daily dose of 0.1, 3, 5, 6, 10, 20, 25, 30 or 50mg, most preferably a daily dose of 0.5, 3, 5, 10 or 20 mg.

In another aspect, the acetylcholinesterase inhibitor may be co-administered with the histamine-3 receptor inverse agonist and the NMDA receptor antagonist in a daily dose of 1mg to 30 mg; e.g. 1, 1.5, 2, 3, 4, 4.5, 5, 6, 8, 9.5, 10, 12, 13, 13.3, 15, 16, 23, 24, 25 or 30mg, preferably in a daily dose of 1, 1.5, 2, 3, 4, 4.5, 5, 6, 8, 9.5, 10, 12, 13, 13.3, 16, 23, 24 or 25mg, most preferably in a daily dose of 1.5, 3, 4, 4.5, 5, 6, 8, 9.5, 10, 12, 13.3, 16, 23 or 24.

In another aspect, the NMDA receptor antagonist memantine may be co-administered with a histamine-3 receptor inverse agonist and an acetylcholinesterase inhibitor in a daily dose of 1mg to 40 mg; e.g. 5, 7, 10, 14, 20, 28 or 40mg, preferably a daily dose of 5, 7, 10, 14, 20 or 28mg, most preferably a daily dose of 5, 10, 14, 20 or 28 mg.

In another aspect, the acetylcholinesterase inhibitor donepezil may be co-administered with the histamine-3 receptor inverse agonist and the NMDA receptor antagonist in a daily dose of 2mg to 30 mg; e.g. 2, 5, 10, 15, 23, 25 or 30mg, preferably a daily dose of 2, 5, 10, 23 or 25mg, most preferably a daily dose of 5, 10 or 23 mg.

In another aspect, the acetylcholinesterase inhibitor rivastigmine may be co-administered with a histamine-3 receptor inverse agonist and an NMDA receptor antagonist in a daily dose of 0.5mg to 15 mg; e.g. 1, 1.5, 3, 4.5, 5, 6, 9.5, 10 or 13.3mg, preferably the daily dose is 1, 1.5, 3, 4.5, 5, 6, 9.5 or 13.3mg, most preferably the daily dose is 1.5, 3, 4.5, 6, 9.5 and 13.3 mg.

In another aspect, the acetylcholinesterase inhibitor galantamine can be co-administered with a histamine-3 receptor inverse agonist and an NMDA receptor antagonist in a daily dose of 1mg to 30 mg; e.g. 1, 2, 4, 6, 8, 12, 16, 24 and 30mg, preferably daily doses of 2, 4, 6, 8, 12, 16 and 24mg, most preferably daily doses of 4, 8, 12, 16 and 24 mg.

In another aspect, the treatment comprises administering to the patient 0.1mg to 100mg of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, per day.

In another aspect, the treatment comprises administering to the patient 0.1mg to 60mg of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, per day.

In another aspect, the treatment comprises administering to the patient 0.1mg to 30mg of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, per day.

In another aspect, the treatment comprises administering to the patient 1mg to 25mg of donepezil or a pharmaceutically acceptable salt thereof per day.

In another aspect, the treatment comprises administering to the patient 5mg to 25mg of donepezil or a pharmaceutically acceptable salt thereof per day.

In another aspect, the treatment comprises administering 5, 10 or 23mg per day of donepezil or a pharmaceutically acceptable salt thereof to the patient.

In another aspect, the treatment comprises administering to the patient 1mg to 40mg of memantine, or a pharmaceutically acceptable salt thereof, per day.

In another aspect, the treatment comprises administering to the patient 5mg to 30mg of memantine, or a pharmaceutically acceptable salt thereof, per day.

In another aspect, the treatment comprises administering to the patient 5, 10, 14, 20, or 28mg of memantine, or a pharmaceutically acceptable salt thereof, per day.

In another aspect, treatment comprises administering the active compound to the patient one to three times daily, one to three times weekly, or one to three times monthly. Preferably, treatment comprises administering the compound to the patient once a day, twice a day, or three times a day. More preferably, the treatment comprises administering the compound to the patient once a day.

Examples

The examples given below are provided by way of illustration only and should not be construed to limit the scope of the invention.

Abbreviations:

ANOVA: analysis of variance

AP: front and back (Anterior Posterior)

aCSF: artificial cerebrospinal fluid

CaCl₂.2H₂O: calcium chloride dihydrate

DV: dorsoventral side (Dorsal Ventral)

DTT: dithiothreitol

EC₅₀: half maximal effective concentration

EDTA: ethylenediaminetetraacetic acid

EEG: electroencephalogram

GDP: guanosine diphosphate

GPCR: g protein-coupled receptors

HCl: hydrochloric acid

h: hour(s)

HEPES (high efficiency particulate air): 4- (2-hydroxyethyl) piperazine-1-ethanesulfonic acid

i.p.: intraperitoneal cavity

i.v.: intravenous administration of drugs

KCl: potassium chloride

K_b: binding constant

K_i: suppression constant

LC-MS/MS: liquid chromatography-mass spectrometry/mass spectrometry

mg: milligrams of

MgCl₂: magnesium chloride

min: minute (min)

ML: inner and outer sides (media Lateral)

And (mM): millimole

nmol/L: nanomole per liter

NaCl: sodium chloride

NaH₂PO₄.2H₂O: sodium dihydrogen phosphate dihydrate

Na₂HPO₄.7H₂O: sodium hydrogen phosphate heptahydrate

NPO: nucleuses kisses brain bridge (nucleous Pontis Oralis)

nM: nano-massage

p.o.: through the mouth

s.c.: under the skin

S.e.m.: standard error of mean

μ M: micro-massage

θ ： Theta

Example 1: determination of K for the human and rat histamine-3 receptor_iValue of

Test compounds were evaluated according to the following procedure to determine K at the human and rat histamine-3 receptor_iThe value is obtained.

Materials and methods:

the receptor source is as follows: recombinant human cDNA expressed in rat brain frontal cortex or CHO cell

A radioligand: [3H] r-alpha-methyl histamine

Final ligand concentration: [3.0nM ]

Non-specific determinants: r-alpha-methyl histamine (100. mu.M)

Reference compound: r-alpha-methyl histamine

Positive control: r-alpha-methyl histamine

Incubation conditions were as follows:

increasing concentrations of test compound or standard with membrane receptor and radioligand at 5mM MgCl₂And 50mM Tris-HCl (pH 7.4) at room temperature for 60 minutes. The reaction was terminated by rapid vacuum filtration on a glass fiber filter. Determining the radioactivity trapped on the filter and comparing it with a control value to determine the amount of radioactivity trapped on the filterAny interaction of the test compound with the cloned human or rat receptor binding site.

As a result:

ND-not subjected to

Reference:

Br J Pharmacol.,2008,154(6):1166–1181.

example 2: determination of IC of histamine-3 receptor₅₀Value of

Test compounds were evaluated to determine IC according to the following procedure₅₀The value is obtained.

Materials and methods:

the receptor source is as follows: human recombination (CHO-K1 cell)

A radioligand: [35S ] -GTP γ S

Final ligand concentration: [0.3nM ]

Reference compound: tiopronamide (Thioperamide)

Positive control: tiopronamide

Incubation conditions were as follows:

elevated concentrations of test compound and/or vehicle were mixed with membrane (0.09mg/mL) and 10. mu.M GDP at 30 ℃ in modified HEPES pH 7.4 buffer (20mM HEPES, pH 7.4,100mM NaCl, 10mM MgCl. RTM. HEPES, pH 7.4)₂1mM EDTA) for 20 minutes, then SPA beads were added and incubated for an additional 60 minutes. By 0.3nM [ 2 ]³⁵S]GTP γ S initiates the reaction for an additional 30 minutes incubation period. Relative to the 3 μ M R (-) - α -MethylHistamine response, test Compound induced³⁵S]A50% or greater (. gtoreq.50%) increase in GTP γ S binding indicates potential histamine-3 receptor agonist activity. The test compound induces [ alpha ] -methyl histamine of 0.03 mu M R (-) -alpha³⁵S]Inhibition of an increase of 50% or more (. gtoreq.50%) of the GTP γ S binding response indicates receptor antagonist activity. These studies were performed and the data were analyzed in the Eurofins Panlabs Taiwan Ltd using standard radioligand binding techniques as described above.

As a result:

compound 1 in humansExhibits inverse agonist-like properties, IC, in the GTP γ S assay of the recombinant histamine-3 receptor₅₀The value was 20 nM.

Reference:

J.Neurochem.,1998,71(2):808-816.

example 3: object recognition task model

The cognitive enhancing properties of the compounds of the invention were evaluated using this model.

Male Wistar rats (8-10 weeks old) were used as experimental animals. Four animals were housed per cage. Starting the day before the experiment, the animals maintained 20% of food deprivation. Water was provided ad libitum throughout the experiment. Animals were maintained in a temperature and humidity controlled room for a 12 hour light/dark cycle. The experiments were performed in an open area made of acrylic acid. On day 1, rats were acclimated to independent fields (open area) without any object.

In familiarity with (T)₁) And selection (T)₂) Prior to the trial, rats received vehicle, donepezil and memantine, or test compound, donepezil and memantine, on the day of acclimation. In the familiarity stage (T)₁) During this period, rats were placed individually in the field for 3 minutes with two identical objects (a)₁And a₂) Located 10cm from the wall. At T₁After 24 hours, the long term memory test was evaluated. The same rats were placed as they were at T₁In the same field as in the test. In the selection phase (T)₂) During this period, rats were allowed to replicate on familiar objects (a)₃) And a new object (b) was present to visit the field for 3 minutes. At T₁And T₂During the trial, a stopwatch was used to record the exploration of each object (defined as sniffing, licking, chewing or moving the nose hair while the nose was pointing at the object at a distance of less than 1 cm)

T₁Is the total time spent exploring a familiar object (a)₁+a₂)。

T₂Is the total time (a) spent exploring familiar and new objects₃+b)。

The discrimination index is in the selection test (T)₂) The time spent in exploring a new object is divided byTo explore the sum of the time spent with new and familiar objects.

Object identification tests were performed as described in Behavioural Brain Research,1988,31, 47-59.

As a result:

vehicle treated animals spent nearly equal time exploring new and familiar objects. The group treated with the combination of test compound, donepezil and memantine took significantly more time to explore new objects. No significant increase in discrimination index was observed in the group treated with donepezil and memantine compared to vehicle treatment. However, the group co-treated with the test compound, donepezil and memantine showed a significant improvement in the memory endpoint (discrimination index). This pro-cognitive effect indicates that the test compound has an enhancing effect on the pro-cognitive effects of donepezil and memantine. The results of this study are provided in fig. 1a and 1 b.

Example 4: assessment of acetylcholine modulation in medial prefrontal cortex of male Wistar rats

The neurotransmitter regulation of the triple combination is evaluated by this model.

Microdialysis catheters were stereotactically implanted under isoflurane anesthesia in the medial prefrontal cortex (mPFC; AP: +3.2mm, ML: -0.5mm, DV: -3.0mm) of male Wistar rats (240 to 300g body weight). Coordinates were obtained from a rat brain atlas (Paxinos and Watson,2004) with the reference point taken from bregma and perpendicular to the skull. Rats were allowed to recover individually for 4 days in a round bottomed Plexiglas (Plexiglas) bowl, with free access to feed and water.

After 4 days of surgical recovery, male Wistar rats were connected to a double quartz lined double channel liquid rotation device (Instech, UK) on a balanced lever arm, which allowed unrestricted movement of the animals. A pre-equilibrated microdialysis probe (2mm dialysis membrane) was inserted into the mPFC through the catheter 16 hours before the start of the study. On the day of the study, artificial cerebrospinal fluid (aCSF; NaCl 147mM, KCl 2.7mM, MgCl) was used₂1mM,CaCl₂.2H₂O1.2 mM, pH 7.4) was perfused with the probe at a flow rate of 1.5 μ L/min and maintained for a 2 hour stationary phase. In the treatment with the test compound (3 or 10mg/kg, p.o.) or vehicleFirst, five base samples were collected at 20 minute intervals. Donepezil (1mg/kg, s.c.) and memantine (1mg/kg, s.c.) were administered 30 minutes after the test compound. Dialysate samples were collected for an additional 4 hours after test compound treatment. The dialysate was stored below-50 ℃ prior to analysis.

Quantification of acetylcholine:

the acetylcholine concentration in the dialysate was quantified using an LC-MS/MS based method.

Statistical analysis:

all microdialysis data for acetylcholine were plotted as percent change from the mean dialysate base concentration, 100% being defined as the mean of the five predose values. The percent change in acetylcholine levels was compared to donepezil and memantine combinations using two-way analysis of variance (time and treatment) followed by a Bonferroni post-test. Area under the curve (AUC) values for percent change in acetylcholine levels were calculated and again the unpaired "t" test was used to compare the statistical significance between mean AUC values versus donepezil and memantine treatments. A p-value less than 0.05 was considered statistically significant. Incorrect probe placement was considered as a criterion to exclude animal data.

Reference:

1.Paxinos G.and Watson C.(2004)Rat brain in stereotaxiccoordinates.Academic Press,New York.

as a result: compound 1

Treatment with donepezil and memantine increased acetylcholine levels to 1726 ± 297% of the maximal basal level. The increase in acetylcholine was significantly higher after combination of compound 1, donepezil and memantine compared to donepezil and memantine combination. After triple combination, the mean maximum increase in acetylcholine was observed to be 2968 ± 585 of the pre-dose level (fig. 2 (a)).

The area under the curve (AUC) calculated after compound 1, donepezil and memantine treatment was significantly higher compared to the donepezil and memantine combination (fig. 2 (b)).

Compound 2

Treatment with donepezil and memantine increased acetylcholine levels to 1365 ± 249% of the maximum basal level. The increase in acetylcholine was significantly higher after combination of compound 2, donepezil and memantine compared to donepezil and memantine combination. After triple combination, the mean maximum increase in acetylcholine was observed to be 2696 ± 504% of the pre-dose level (fig. 3 (a)).

The area under the curve (AUC) calculated after compound 2, donepezil and memantine treatment was significantly higher compared to the donepezil and memantine combination (fig. 3 (b)).

Compound 3

Treatment with donepezil and memantine increased acetylcholine levels to 1375 ± 461% of the maximum basal level. The increase in acetylcholine was significantly higher after the combination of compound 3, donepezil and memantine compared to the combination of donepezil and memantine. After triple combination, the mean maximum increase in acetylcholine was observed to be 2674 ± 271 of the pre-dose level (fig. 4 (a)).

The mean area under the curve (AUC) calculated after compound 3, donepezil and memantine treatment was significantly higher compared to the donepezil and memantine combination (fig. 4 (b)).

Example 5: assessment of theta modulation in the dorsal hippocampus of anesthetized male Wistar rats

The effect of the triple combination on brain activity as a pharmacodynamic endpoint was evaluated using this model.

Male Wistar rats (240 to 320g) were anesthetized by intraperitoneal administration of urethane (1.2 to 1.5g/kg) for catheter implantation in the left femoral vein. Animals were placed in stereotactic frames for implantation of electrodes (stainless steel wire, Plastics One) into the dorsal hippocampus (AP: -3.8 mm; ML: +2.2 mm; DV: -2.5 mm; Paxinos and Watson, 2004). Bipolar stimulating electrodes (untwisted stainless steel wires with tips spaced 0.75-1.0mm apart, Plastics One) were implanted into Nucleus Pontis Oralis (NPO; AP: -7.8 mm; ML:1.8 mm; DV: -6.0 mm; Paxinos and Watson, 2004). In addition, one electrode was implanted in the cerebellum as a reference. Hippocampal theta rhythms were induced by a 6 second electrical stimulation sequence (20-160 μ Α,0.3-ms pulse duration, 250Hz) delivered to the NPO at a rate of 0.01 sequence/second using a Grass S88 stimulator and a psuu 6 stimulation isolation device (Grass Medical Instruments, Quincy, MA). EEGs were recorded at a rate of 1000Hz using Ponemah (version 5.2) software and stored for offline analysis using Neurosphere (version 3.0). The baseline amplitude level is achieved by using the current required to direct the theta rhythm to 50% of the maximum amplitude under controlled conditions. After a stabilization period of 1 hour, baseline recordings were made for 30 minutes, then treated with vehicle or compound 1(1mg/kg, i.v.). Donepezil (0.3mg/kg, i.v.) and memantine (0.3mg/kg, i.v.) were administered 30 minutes after compound 1 treatment and recording continued for an additional 1 hour.

Statistical analysis:

the power of the theta rhythm frequency during the stimulation period during the 30 minute baseline was calculated and the% change in these measurements after treatment was calculated. The percent change in relative theta power after triple combination of compound 1, donepezil and memantine was compared to donepezil and memantine using two-way analysis of variance (time and treatment) followed by a Bonferroni post test. A p-value less than 0.05 was considered statistically significant.

Reference:

1.Paxinos G.and Watson C.(2004)Rat brain in stereotaxiccoordinates.Academic Press,New York.

as a result:

treatment with donepezil and memantine in combination produced a modest increase in hippocampal theta power. Compound 1 in combination with donepezil and memantine produced a significant increase in theta power levels with peak levels reaching 167 ± 11% of the pre-dose levels. The effect in the triple combination was observed to be significantly higher than the combination of donepezil and memantine (fig. 5 (a)).

The area under the flat curve value (AUC) calculated after compound 1, donepezil and memantine treatment was significantly higher compared to donepezil and memantine combination (fig. 5 (b)).

Claims (21)

1. A combination product comprising a histamine-3 receptor inverse agonist, an acetylcholinesterase inhibitor and an NMDA receptor antagonist for use in the treatment of a cognitive disorder in a patient; wherein the histamine-3 receptor inverse agonist is selected from the group consisting of: n- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide;

n- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide; or

N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide;

or a pharmaceutically acceptable salt thereof;

the acetylcholinesterase inhibitor is donepezil or a pharmaceutically acceptable salt thereof, and the NMDA receptor antagonist is memantine or a pharmaceutically acceptable salt thereof.

2. A combination product according to claim 1 wherein the histamine-3 receptor inverse agonist is N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof.

3. A combination product according to claim 1 wherein the pharmaceutically acceptable salt is selected from,

n- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride;

2- (morpholin-4-yl) acetamide tartrate, N- [4- (1-cyclopropylpiperidin-4-yloxy) phenyl ] -N- [4- (morpholin-4-yl) acetamide tartrate; or

N- [4- (1-isopropylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide tartrate.

4. The combination product according to any one of claims 1, 2 or 3, wherein the histamine-3 receptor inverse agonist is N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride.

5. A combination product according to claim 1 wherein the acetylcholinesterase inhibitor is donepezil hydrochloride.

6. The combination product of claim 1, wherein the NMDA receptor antagonist is memantine hydrochloride.

7. A combination comprising N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide dihydrochloride, donepezil hydrochloride, and memantine hydrochloride.

8. A combination product as claimed in any one of claims 1 to 7 for use in the treatment of cognitive disorders in a patient.

9. A combination product according to claim 8 wherein the cognitive disorder is selected from Alzheimer's disease, schizophrenia, Parkinson's disease, dementia with Lewy bodies, vascular dementia, frontotemporal dementia, Down's syndrome or Tourette's syndrome.

10. Use of a combination product as defined in any one of claims 1 to 7 in the manufacture of a medicament for the treatment of cognitive disorders in a patient in need thereof.

11. Use of a combination product as claimed in claim 10, wherein the cognitive disorder is selected from alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia, frontotemporal dementia, down's syndrome or tourette's syndrome.

12. A combination comprising N- [4- (1-cyclobutyl-piperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, an acetylcholinesterase inhibitor and an NMDA receptor antagonist for use in the treatment of alzheimer's disease in a patient; wherein the acetylcholinesterase inhibitor is donepezil or a pharmaceutically acceptable salt thereof, and the NMDA receptor antagonist is memantine or a pharmaceutically acceptable salt thereof.

13. A combination product according to claim 12, (a) wherein the N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, an acetylcholinesterase inhibitor and an NMDA receptor antagonist are administered in combination for the treatment of a patient, or

(b) Wherein the N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof is administered as adjunctive therapy to a patient stably treated with an acetylcholinesterase inhibitor and an NMDA receptor antagonist; wherein the acetylcholinesterase inhibitor is donepezil or a pharmaceutically acceptable salt thereof, and the NMDA receptor antagonist is memantine or a pharmaceutically acceptable salt thereof.

14. Use of a combination product according to claim 12 for the manufacture of a medicament for the treatment of Alzheimer's disease in a patient,

(a) wherein 0.1mg to 100mg of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof is administered to the patient per day, or

(b) Wherein 0.1mg to 60mg of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof is administered to the patient per day, or

(c) Wherein 0.1mg to 30mg of N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof is administered to the patient per day, and

(d) wherein 1mg to 30mg of donepezil or a pharmaceutically acceptable salt thereof is administered to the patient per day, and

(e) wherein from 1mg to 40mg of memantine, or a pharmaceutically acceptable salt thereof, is administered to the patient daily.

15. A pharmaceutical composition comprising a combination product as claimed in any one of claims 1 to 7, and a pharmaceutically acceptable excipient.

16. The pharmaceutical composition according to claim 15 for the treatment of cognitive disorders selected from alzheimer's disease, schizophrenia, parkinson's disease, dementia with lewy bodies, vascular dementia or frontotemporal dementia.

17. The pharmaceutical composition of claim 15, (a) wherein the N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, is present in an amount of 0.1mg to 100mg, or

(b) Wherein the N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof is present in an amount of 0.1mg to 60mg, or

(c) Wherein the N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide or a pharmaceutically acceptable salt thereof is present in an amount of 0.1mg to 30mg, and

(d) wherein the donepezil or pharmaceutically acceptable salt thereof is present in an amount of 2mg to 30mg, and

(e) wherein the memantine, or a pharmaceutically acceptable salt thereof, is present in an amount of 1mg to 40 mg.

18. Use of a combination according to claim 12 or claim 13 in the manufacture of a medicament for the treatment of alzheimer's disease in a patient, wherein N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, is administered to the patient by the oral or parenteral route.

19. The use according to claim 18, wherein N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, is administered to the patient by a topical route.

20. The use according to claim 18, wherein N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, is administered to the patient by nasal or dermal route.

21. Use of a combination product according to claim 12 or claim 13 in the manufacture of a medicament for the treatment of alzheimer's disease in a patient, wherein N- [4- (1-cyclobutylpiperidin-4-yloxy) phenyl ] -2- (morpholin-4-yl) acetamide, or a pharmaceutically acceptable salt thereof, is administered to the patient one to three times daily, one to three times weekly or one to three times monthly.