METHOD FOR IDENTIFYING CRMP MODULATORS

Abstract

The present invention refers to a method for identifying a modulator of CRMP suitable for the prevention, alleviation or/and treatment of CRMP-associated diseases.

Description

The present invention refers to a method for identifying a modulator of CRMP suitable for the prevention, alleviation or/and treatment of CRMP associated diseases. The present invention further refers to a cell capable of overexpressing or underexpressing CRMP, and to a non-human animal comprising such cell. Further subjects of the present invention are compounds suitable for the prevention, alleviation or/and treatment of CRMP-associated diseases.

Charrier et al. (Molecular Neurobiology, 2003, 28:51-63) describe the family of collapsin response mediator proteins (CRMP-1 to 5) as developmentally regulated proteins strongly expressed in postmitotic neural cells in the developing nervous system. In the adult brain, the CRMPs are dramatically down-regulated.

CRMP-2 (also called CRMP-62; Dihydropyrimidinase-related protein 2, DRP-2; TOAD-64; Ulip2) is described in the literature as being involved in the regulation of neuronal polarity. CRMP-2 binds to tubulin heterodimers and promotes microtubule assembly. CRMP-2/tubulin complexes modulate microtubule dynamics and contribute to axonal growth.

In hippocampal neurons, CRMP-2 accumulates in the distal part of the growing axons. Overexpression of CRMP-2 induces the formation of multiple axons, in contrast to axons normally having a single axon and several dendrites. Overexpression of CRMP-2 promotes axonal growth and branching. CRMP-2 blockade inhibits axon formation and CRMP-2 inhibition attenuates neurotrophic factor induced axon propagation (NT3/BDNF). Dominant negative mutants of CRMP-2 (truncated mutants) suppress axonal growth (Arimura N. et al., J. Neurobiol. 2004, 58:34-47).

Axogenesis and spatial and temporal dendrite formation have serious effects on the function of the nervous system. Disruptions of neuronal polarity are frequently associated with mental illness such as neurodegenerative diseases, e.g. Alzheimer's disease.

Nakata et al. (Biol. Psychiatry 2003, 53:571-576) discuss the role of CRMP-2 polymorphism in paranoid-type schizophrenia on the basis of allele frequencies of CRMP-2 gene polymorphism. The correlation suggests that a specific mutation may reduce the susceptibility to schizophrenia, especially to the paranoid subtype. There is no hint that CRMP-2 would be a target for therapy of schizophrenia, e.g. in combination with antipsychotic drugs.

In Down syndrome and Alzheimer patients, deranged CRMP-2 levels may contribute to the abnormal plasticity and wiring observed in the brains of these patients (Nakata et al., Biol Psychiatry 2003; 53:571-576).

In hypothyroidism, which is characterized by abnormalities of central nervous system development, CRMP-2 was found to be dysregulated (Charrier et al., Mol. Neurobiology. 2003; 28(1): 51-63).

In Parkinson's disease, CRMP-2 could be involved in dopamine-induced neuronal apoptosis, possibly via semaphorin 3A (Charrier et al., Mol. Neurobiology. 2003; 28(1): 51-63). There is, however, no indication that CRMP-2 would be a target for the treatment of Parkinsonian tremor syndromes.

CRMP-2 was shown to interact directly with PLD₂ (Lee et al., J. Biol. Chem. 2002, 277:6542-6549) by amino acids 243-300 (rat CRMP-2). CRMP-2 was found to inhibit PLD₂ activity concentration dependently in COS-7 cells. CRMP-2 was found to be co-localized in the distal tips of neurites in differentiated PC12 cells. In PC12 cells, semaphorin 3A inhibits PLD₂ activity, indicating the CRMP-2 may be an intracellular mediator of semaphorin 3A.

Phosphorylation of CRMP-2 seems to be the major regulatory mechanism of CRMP-2 activity. Phosphorylated CRMP-2 is inactive; dephosphorylated CRMP-2 regulates microtubule assembly in axons by regulation of the polymerization rate by the tubulin dimer pool and stabilization of the microtubule polymer (Nakata et al., Biol Psychiatry 2003; 53:571-576). Glycogen synthase kinase-3β (GSK-3β) was shown to phosphorylate CRMP-2 at Thr-514, thus inactivating it and thereby regulating neurotrophin-induced axonal outgrowth (Yoshimura et al, Cell 2005; 120: 137-149).

Apart from its function in neurodevelopment, CRMP-2 was shown to be involved in pathways that regulate the proliferation of non-neuronal cells through its phosphorylation by regulatory proteins. It was suggested that de-regulation of CRMP-2 phosphorylation levels may lead to aberrant cell proliferation and consequently, tumorgenesis (Tahimic et al, Biochem. Biophys. Res. Commun. 2006; 340:1244-1250).

Czech et al. (Neurochemical Research 2004, 29:2189-2196) describe reduction of CRMP-2 in patients suffering from mesial temporal lobe epilepy (MTLE).

The CRMP-2 family of proteins is implicated in developmental process of the nervous system since most of the five CRMP proteins are highly expressed during early development and mainly in the central nervous system. On an in-vitro level, CRMP-2 has been shown to be involved in neuronal differentiation, polarization and axonal outgrowth induced by neurotrophic factors such as brain derived neurotrophic factor (BDNF). Interestingly re-arrangement of neuronal connections and erroneous neuronal outgrowth has been implicated in the pathophysiology of epilepsy and neuropathic pain (Pezet, McMchon, Ann. Rev. Neurosci 2006, 29:507-38, Binder 2004, Adv. Exp. Med. Biol. 548:34-56). Moreover, BNDF is involved in the development of epilepsy and chronic pain in animal models.

Lacosamide (international non-proprietory name) is known to be an anticonvulsant and analgesic drug. Lacosamide belongs to a class of peptidic compounds known to exhibit central nervous system activity. These peptides are described in the U.S. Pat. Nos. 5,378,729 and 5,773,475. In the context of the present invention, these compounds are referred to as Lacosamide-related compounds.

The standard chemical nomenclature of Lacosamide is (R)-2-acetamide-N-benzyl-3-methoxypropionamide. Lacosamide is also known as SPM 927 or Harkoseride.

Lacosamide is in phase III clinical development in the indications epilepsy and diabetic neuropathy pain. Preclinical data support a potential of Lacosamide in the treatment of the following pain syndromes: diabetic neuropathy, chemotherapy-induced neuropathy, fibromyalgia, osteoarthritis, cancer pain, nerve lesion-induced pain, inflammatory pain and central pain. Additional preclinical data support a potential of Lacosamide in the treatment of the following disease areas: essential tremor, dyskinesias, migraine prophylaxis, amyotrophic lateral sclerosis and psychosis, especially schizophrenia. Finally, Lacosamide has shown preclinical and clinical efficacy for the treatment of complex partial seizures with and without secondary generalization, and status epilepticus.

The mechanism of action of anticonvulsants in disease treatment is only beginning to be understood. The broad activity of Lacosamide is described in various disease models, although the molecular mode of action for these effects remains unknown.

It was therefore the object of the present invention to provide a method of identifying compounds suitable for the prevention, alleviation or/and treatment of diseases or conditions which can be treated by Lacosamide, based on the mode of action of Lacosamide. Surprisingly, in protein binding experiments, it was found that Lacosamide binds directly to CRMP-2 in extracts obtained from rat brain. The binding was confirmed in experiments employing heterologously expressed human CRMP-2 in Xenopus oocytes. A functional interaction of CRMP-2 and Lacosamide was shown in experiments exploring the effect of Lacosamide on the neurotrophin-induced stimulation of axonal outgrowth in cultured hippocampal neurons. CRMP-2 is therefore regarded as a target of Lacosamide in the nervous system in treatment of epilepsy, pain, essential tremor, dyskinesias, amyotrophic lateral sclerosis, schizophrenia and other diseases or conditions as described herein.

This object is achieved according to the invention by a method for identifying a modulator of CRMP suitable for the prevention, alleviation or/and treatment of a CRMP associated disease, comprising the steps

• • (a) selecting a substance,
  • (b) contacting the substance selected in step (a) with CRMP, and
  • (c) determining whether CRMP interacts with the substance,
    wherein a substance interacting with CRMP is a modulator of CRMP, in particular a modulator of CRMP suitable for the prevention, alleviation or/and treatment of a CRMP associated disease.

The CRMP associated disease of the present invention may be a disease which can by prevented, alleviated or/and treated by Lacosamide or a Lacosamide-related compound.

A preferred CRMP associated disease is a CRMP-2 associated disease.

It is preferred that the CRMP associated disease, in particular the CRMP-2 associated disease is a neurological disease, such as epilepsy, a pain syndrome, a motoneuron disorder, a dyskinesia, or a tremor syndrome. “Neurological disease” also includes arthritic conditions like osteoarthritis, rheumatoid arthritis including juvenile rheumatoid arthritis, fibromyalgia, and musculoskeletal disorders as defined herein.

It is also preferred that the CRMP associated disease, in particular the CRMP-2 associated disease, is a psychiatric disease, such as psychosis or/and schizophrenia.

It is also preferred that the CRMP associated disease, in particular the CRMP-2 associated disease, is an inflammatory disease such as arthritis or an arthritic condition associated with inflammation, e.g. inflammatory osteoarthritis.

Thus, the CRMP associated disease, in particular the CRMP-2 associated disease, is preferably selected from neurological diseases, psychiatric diseases, or/and inflammatory diseases.

The CRMP associated disease, in particular the CRMP-2 associated disease, is also preferably selected from psychiatric diseases, and inflammatory diseases.

It is also preferred that the CRMP-associated disease, in particular the CRMP-2 associated disease, of the present invention is selected from epilepsy, pain syndromes, motoneuron disorders, dyskinesias, tremor syndromes, psychosis, especially schizophrenia, arthritis or an arthritic condition such as fibromyalgia and osteoarthritis, any condition or disease included therein as described herein, and combinations thereof.

It is also preferred that the CRMP-associated disease, in particular the CRMP-2 associated disease, of the present invention is selected from epilepsy, pain syndromes, dyskinesias, tremor syndromes, psychosis, especially schizophrenia, arthritis or an arthritic condition such as fibromyalgia and osteoarthritis, any condition or disease included therein as described herein, and combinations thereof.

It is more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease, is selected from epilepsy, pain syndromes, motoneuron disorders, dyskinesias, tremor syndromes different from Parkinsonian tremor syndrome, arthritis or an arthritic condition such as fibromyalgia and osteoarthritis, any condition or disease included therein as described herein, and combinations thereof.

It is also more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease, is selected from epilepsy, pain syndromes, dyskinesias, tremor syndromes different from Parkinsonian tremor syndrome, arthritis or an arthritic condition such as fibromyalgia and osteoarthritis, any condition or disease included therein as described herein, and combinations thereof.

It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease is selected from epilepsy and epilepsy conditions as described herein.

It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease is selected from pain syndromes.

It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease is selected from motoneuron disorders.

It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease is selected from dyskinesias.

It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease is selected from tremor syndromes, such as tremor syndromes different from Parkinsonian tremor syndrome.

It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease is psychosis, especially schizophrenia.

It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease is selected from arthritis or an arthritic condition such as fibromyalgia and osteoarthritis. It is even more preferred that the CRMP-associated disease of the present invention, in particular the CRMP-2 associated disease, is selected from epilepsy, pain syndromes, arthritis or an arthritic condition such as fibromyalgia and osteoarthritis, any condition or disease included therein as described herein, and combinations thereof. Preferred epilepsy conditions are status epilepticus and complex partial seizures with and without secondary generalization. A preferred pain syndrome is painful diabetic neuropathy, preferably associated with Diabetes mellitus Type I or II, more preferably Type II. Another preferred pain syndrome is pain associated with arthritis or an arthritic condition, in particular with osteoarthritis.

Epilepsy includes, but is not limited to, complex partial seizures with and without secondary generalization, status epilepticus and a status epilepticus-related condition, e.g. acute repetitive seizures, seizure clusters, etc. Further, epilepsy, in particular before/during acute seizures, may require neuroprotective treatment to reduce brain damage, short term memory loss, cognitive decline, or/and additional seizures (anti-epileptogenesis). Status epilepticus includes partial or/and generalized seizures. Generalized seizures can be convulsive, such as tonic-clonic, tonic, clonic, or myoclonic seizures, or non-convulsive, such as absences or atonic seizures. Details of the prevention, alleviation or/and treatment of status epilepticus and neuroprotective treatment by Lacosamide are described in EP 1 541 138, the disclosure of which is incorporated herein by reference.

Further, epilepsy includes a refractory epileptic condition. The term “refractory epileptic condition” herein refers to an epileptic disease state such as status epilepticus, an epileptic seizure, a repetitive seizure or a seizure cluster that is at least partially or substantially resistant to treatment with one or more anti-epileptic drugs. The term “refractory status epilepticus” herein refers to status epilepticus as defined above exhibiting at least partial or substantial resistance to treatment with one or more anti-epileptic drugs. Such drugs in either case include benzodiazepines, barbiturates and anticonvulsants other than a compound of Formula (I) as defined herein. For example and without limitation, resistance can be exhibited to treatment with one or more drugs selected from diazepam, lorazepam, midazolam, phenobarbital, carbamazepine, phenyloin, fosphenyloin, oxcarbazepine, lamotrigine, gabapentin, pregabalin, valproic acid, pentobarbital, thiopental, propofol and pharmaceutically acceptable salts thereof. Details of the prevention, alleviation or/and treatment of refractory status epilepticus and neuroprotective treatment by compounds of Formulae (I), (II) or/and (III) as described herein, in particular Lacosamide, are described in PCT/EP2007/005306 the disclosure of which is incorporated herein by reference.

Further, refractory status epilepticus as used herein may be initially responsive to treatment with such drugs but becomes at least partially refractory when it lasts for at least about 10 minutes, for example at least about 15 minutes, at least about 20 minutes, at least about 30 minutes, at least about 45 minutes or at least about 60 minutes.

Further, a refractory epileptic condition including refractory status epilepticus can be present a priori, or, in the case of refractory status epilepticus, can be associated with the duration of status epilepticus as indicated above.

It is preferred that epilepsy as used herein is not mesial temporal lobe epilepsy (MTLE).

Pain syndromes include, but are not limited to, allodynia, phantom pain, acute and chronic pain, neuropathic pain including central neuropathic pain and peripheral neuropathic pain, painful diabetic neuropathy, painful conditions associated with or/and caused by cortical spreading depression (CSD), pain associated with a mononeuropathy, tumor pain, chemotherapy induced pain, nucleoside induced pain, and nucleoside analogue induced pain, non-inflammatory musculoskeletal pain, pain associated with arthritis or with an arthritic condition.

Allodynia includes, but is not limited to, allodynia as a major and unique pain symptom independent of the nature of the underlying disease, and phantom pain. Details of the prevention, alleviation or/and treatment of allodynia by Lacosamide are described in EP 1 243 263, the disclosure of which is incorporated herein by reference.

Details of the prevention, alleviation or/and treatment of phantom pain by the CRMP modulator Lacosamide are described in EP 1 243 263, the disclosure of which is incorporated herein by reference.

Acute and chronic pain include, but are not limited to, non neuropathic inflammatory pain including chronic inflammatory pain, rheumatoid arthritis pain, and secondary inflammatory osteoarthritic pain. Details of the prevention, alleviation or/and treatment of acute and chronic pain by Lacosamide are described in EP 1 243 262, the disclosure of which is incorporated herein by reference.

Neuropathic pain includes, but is not limited to, pain associated with lesions of the nervous system. Neuropathic pain includes peripheral and central neuropathic pain.

Central neuropathic pain includes, but is not limited to, spinal cord injury pain or/and CNS injury pain. Details of the prevention, alleviation or/and treatment of central neuropathic pain by Lacosamide are described in WO 2005/053667 A1, the disclosure of which is incorporated herein by reference.

Peripheral neuropathic pain includes, but is not limited to, pain associated with injury, infection or dysfunction of peripheral sensory nerves.

Painful diabetic neuropathy includes, but is not limited to, a condition associated with painful diabetic neuropathy, such as, but not limited to, average daily pain, overall pain, present pain intensity, pain interference with sleep, the subject's perception of pain interference with general activity, the patients' global impression of change in pain, clinical global impression of change in pain, the subject's perception of different neuropathic pain qualities, quality of life and proportion of pain-free days. A preferred painful diabetic neuropathy is a diabetic distal sensory polyneuropathy. The painful diabetic neuropathy may be associated with Diabetes mellitus Type I or Diabetes mellitus Type II. Details of the prevention, alleviation or/and treatment of painful diabetic neuropathy by Lacosamide are described in WO 2005/092313 A1, the disclosure of which is incorporated herein by reference.

Painful conditions associated with or/and caused by cortical spreading depression (CSD) include, but are not limited to, chronic headache, cerebral ischemia during stroke or cardiovascular surgery, traumatic brain injury, subarachnoid hemorrhage or transient global amnesia. The chronic headache associated with or/and caused by CSD may be selected from migraine and other forms of chronic headache of both central and peripheral origin such as, but not limited to, cluster headache, tension-type headache, secondary headaches associated with over use of medication, cranial neuralgias, brain trauma and vascular or metabolic disorders. The migraine is preferably acute migraine. Details of the prevention, alleviation or/and treatment of painful conditions associated with or/and caused by CSD, in particular chronic headache, with Lacosamide are described in WO 2005/099740 A1, the disclosure of which is incorporated herein by reference.

Pain associated with a mononeuropathy includes, but is not limited to, trigeminal neuropathic pain, pain associated with trigeminal neuralgia, and atypical facial pain. Details of the prevention, alleviation or/and treatment of trigeminal neuropathic pain by Lacosamide are described in WO 2005/120539 A2, the disclosure of which is incorporated herein by reference.

Tumor pain includes, but is not limited to, tumor pain associated with AIDS, bone cancer pain, pain produced during tumor progression by infiltration in or pressure on bone, viscera, soft tissue or/and nerves, metastasis-induced pain, metastasis-induced bone cancer pain or/and pain induced by metastatic disease in patients with breast, prostate or/and lung cancer.

Chemotherapy-induced pain includes, but is not limited to, chemotherapy-induced neuropathic pain, vinca alkaloid-induced pain or/and vincristine-induced pain.

Nucleoside or/and nucleoside analogue-induced pain include, but are not limited to, painful peripheral neuropathy induced by nucleosides or/and nucleoside analogues, pain induced by anti-tumor or/and anti-viral nucleoside analogues, pain induced by anti-viral nucleoside analogues in AIDS therapy, and pain induced by AZT, ddC, ddI or/and d4T.

Details of the prevention, alleviation or/and treatment of tumor pain, chemotherapy induced pain, nucleoside induced pain and nucleoside analogue induced pain by Lacosamide are described in WO 2006/021412 A2, the disclosure of which is incorporated herein by reference.

Details of the prevention, alleviation or/and treatment of non-inflammatory musculoskeletal pain, in particular specific manifestations of non-inflammatory musculoskeletal pain such as muscular hyperalgesia or/and allodynia occurring in fibromyalgia, myofascial pain syndrome or/and back pain are described in the unpublished application EP 05 017 979.9, which is included herein by reference.

In the present invention, non-inflammatory musculoskeletal pain includes, but is not limited to non-inflammatory musculoskeletal pain associated with or/and caused by a pathological condition. Preferably, this condition is selected form regional pain syndrome such as back or neck pain, rheumatoid arthritis, osteoarthritis, gout, ankylosing spondylitis, lupus erythematosus, fibromyalgia, fibrositis, fibromyositis, myofascial pain syndrome, autoimmune disorders, polymyalgia rheumatica, polymyositis, dermatomyositis, muscular abscess, trichinosis, Lyme disease, Malaria, Rocky Mountain spotted fever, and polio.

Non-inflammatory musculoskeletal pain may be responsible for a number of symptoms, which may be remedied or at least relieved by the treatment of the non-inflammatory musculoskeletal pain. Therefore, in the present invention, non-inflammatory musculoskeletal pain includes, but is not limited to a condition associated with or/and caused by non-inflammatory musculoskeletal pain. Preferably, this condition is selected from fatigue, sleep disorder, irritable bowel syndrome, chronic headache, temporo-mandibular joint dysfunction syndrome, multiple chemical sensitivity, painful menstrual periods, dysmenorrhea, chest pain, morning stiffness, cognitive or memory impairment, numbness and tingling sensations, muscle twitching, irritable bladder, the feeling of swollen extremities, skin sensitivities, dry eyes and mouth, frequent changes in eye prescription, dizziness and impaired coordination.

Pain associated with arthritis or/and pain associated with an arthritic condition includes, but is not limited to osteoarthritic pain such as inflammatory osteoarthritic pain and non-inflammatory osteoarthritic pain, pain associated with rheumatoid arthritis including juvenile rheumatoid arthritis, fibromyalgia pain and pain associated with a musculoskeletal disorder of one or more joints of a subject including arthritis associated with or secondary to conditions not necessary primarily arthritic. An arthritic condition includes, but is not limited to psoriatic arthritis, infectious arthritis, ankylosing spondylitis, neurogenic arthropathy and polyarthralgia. Conditions to which arthritis can be secondary include without limitation Sjögren's syndrome, Behçet's syndrome, Reiter's syndrome, systemic lupus erythematosus, rheumatic fever, gout, pseudogout, Lyme disease, sarcoidosis and ulcerative colitis.

The definition of pain associated with arthritis or with an arthritic condition overlaps with non-inflammatory musculoskeletal pain as defined herein.

Motoneuron disorders include, but are not limited to, amyotrophic lateral sclerosis (ALS), progressive spinal muscular atrophy such as progressive monomelic, focal or segmental spinal muscular atrophy, progressive bulbar palsy, proximal hereditary motor neuropathy, and peripheral neuropathies, such as, but not limited to, Guillain-Barré Syndrome and Charcot-Marie-Tooth Syndrome. Details of the prevention, alleviation or/and treatment of motoneuron disorders such as ALS by Lacosamide are described in WO 2005/120476 A2, the disclosure of which is incorporated herein by reference.

In one embodiment, motoneuron disorders are not myelin disorders. In a further embodiment, motoneuron disorders include, but are not limited to, amyotrophic lateral scierorsis, progressive spinal muscular atrophy such as progressive monomelic, focal or segmental spinal muscular atrophy, progressive bulbar palsy, and proximal hereditary motor neuropathy.

Dyskinesias include, but are not limited to, primary dyskinesias such as, but not limited to, Huntington's chorea and cerebral palsy, and secondary dyskinesias such as, but not limited to, tardive and L-DOPA-induced dyskinesia. The dyskinesia forms include chorea, athetosis, dystonia, ballismus, and combinations thereof. Details of the prevention, alleviation or/and treatment of dyskinesias by Lacosamide are described in WO 2005/110390, the disclosure of which is incorporated herein by reference.

Tremor includes, but is not limited to, essential tremor, physiologic tremor, enhanced physiologic tremor, undetermined tremor syndrome, primary orthostatic tremor, dystonic tremor, task- and position-specific tremors, Parkinsonian tremor syndromes, cerebellar tremor syndromes, Holmes tremor, palatal tremors, neuropathic tremor syndrome, drug-induced and toxic tremor syndromes, psychogenic tremor, myorhythmia, rest tremor, action tremor, postural tremor, kinetic tremor, task- or position-specific tremor or isometric tremor. Details of the prevention, alleviation or/and treatment of tremor by Lacosamide are described in WO 2006/000397, the disclosure of which is incorporated herein by reference.

It is preferred that tremor does not include Parkinsonian tremor syndromes.

Psychosis includes, but is not limited to, schizophrenia, psychosis associated with bipolar disorder, autism, Alzheimer's disease, attention deficit hyperactivity disorder, drug or/and alcohol abuse, affective disorders, dyskinesias and related disorders, dementia, mental retardation, polydipsia/hyponatremia, severe personality disorder, acute episodes of mania, obsessive compulsive disorder, intractable chronic insomnia, Huntington's Disease, Tourette's syndrome, Parkinson's disease or/and dopaminergic therapy of Parkinson's disease.

Details of the prevention, alleviation or/and treatment of schizophrenia in an add-on therapy by Lacosamide are described in PCT/EP2006/000722, the disclosure of which is incorporated herein by reference.

Preferably, the CRMP-associated disease of the present invention is not psychosis, in particular not schizophrenia.

Arthritis or an arthritic condition includes, but is not limited to osteoarthritis such as inflammatory osteoarthritis and non-inflammatory osteoarthritis, rheumatoid arthritis including juvenile rheumatoid arthritis, fibromyalgia and a musculoskeletal disorder of one or more joints of a subject including arthritis associated with or secondary to conditions not necessary primarily arthritic. Osteoarthritis can be idiopathic or primary in origin, or secondary to other conditions. Arthritic conditions and conditions to which arthritis can be secondary as used herein are defined herein in the context of pain associated with arthritis or an arthritic condition.

In the context of the present invention, “CRMP” includes any CRMP polypeptide, in particular any CRMP polypeptide described in the state of the art, such as CRMP-1, CRMP-2, CRMP-3, CRMP-4 and CRMP-5 including splice variants thereof. For instance, two splice variants of CRMP-1 have been described.

FIG. 4 demonstrates that, for instance, CRMP-2 is highly conserved among vertebrate species, in particular among mammalian species. Preferably, CRMP is obtained from a vertebrate species, more preferably from a mammalian species. “CRMP” also includes any nucleic acid encoding a CRMP polypeptide.

“CRMP” also includes a modified CRMP polypeptide. As used herein, “modified CRMP polypeptide” includes but is not limited to modifications of the CRMP sequence as defined herein. Further, “modified CRMP polypeptide” includes but is not limited to post-translational and chemical modifications of CRMP. The person skilled in the art knows suitable methods of chemically modifying a polypeptide, for instance by conjugation at functional groups of amino acid side chains.

SEQ ID NO: 1 describes a nucleotide sequence encoding a CRMP-1 (Genbank NM_—001014809.1, GI:62422570). SEQ ID NO: 1 describes a first splice variant of a CRMP-1.

SEQ ID NO: 2 describes a CRMP-1 encoded by SEQ ID NO: 1.

SEQ ID NO: 3 describes a nucleotide sequence encoding another CRMP-1 (Genbank NM_—001313.3, GI:62422567). SEQ ID NO: 3 describes a second splice variant of a CRMP-1.

The CRMP-1 nucleic acid preferably comprises SEQ ID NO:1 or/and 3 or a fragment thereof.

SEQ ID NO: 4 describes a CRMP-1 encoded by SEQ ID NO: 3.

The CRMP-1 polypeptide preferably comprises SEQ ID NO:2 or/and 4 or a fragment thereof.

SEQ ID NO: 5 describes a nucleotide sequence encoding a CRMP-2 (Genbank BC056408.1, GI:33991633). The CRMP-2 nucleic acid preferably comprises SEQ ID NO:5 or a fragment thereof.

SEQ ID NO: 6 describes a CRMP-2 encoded by SEQ ID NO: 5. The CRMP-2 polypeptide preferably comprises SEQ ID NO:6 or a fragment thereof.

SEQ ID NO: 7 describes a nucleotide sequence encoding a CRMP-3 (Genbank NM_—006426.1, GI:11321616). The CRMP-3 nucleic acid preferably comprises SEQ ID NO:7 or a fragment thereof.

SEQ ID NO: 8 describes a CRMP-3 encoded by SEQ ID NO: 7. The CRMP-3 polypeptide preferably comprises SEQ ID NO:8 or a fragment thereof.

SEQ ID NO: 9 describes a nucleotide sequence encoding a CRMP-4 (Genbank NM_—001387.2, GI:45505175). The CRMP-4 nucleic acid preferably comprises SEQ ID NO:9 or a fragment thereof.

SEQ ID NO: 10 describes a CRMP-4 encoded by SEQ ID NO: 9. The CRMP-4 polypeptide preferably comprises SEQ ID NO:10 or a fragment thereof.

SEQ ID NO: 11 describes a nucleotide sequence encoding a CRMP-5 (Genbank NM_—020134.2, GI:19923820). The CRMP-5 nucleic acid preferably comprises SEQ ID NO:11 or a fragment thereof.

SEQ ID NO: 12 describes a CRMP-5 encoded by SEQ ID NO: 11. The CRMP-5 polypeptide preferably comprises SEQ ID NO:12 or a fragment thereof.

“CRMP” also includes complementary sequences to the sequences described herein. For instance, transcripts to be translated are complementary to the respective coding DNA sequences. Further, complementary sequences may serve as template for synthesis of a nucleic acid to be transcribed. Thus, complementary sequences of SEQ ID Nos: 1, 3, 5, 7, 9, and 11 and fragments thereof are also suitable in the method of the present invention. The complementary sequences to SEQ ID Nos: 1, 3, 5, 7, 9, and 11 may encode for a polypeptide of SEQ ID Nos: 2, 4, 6, 8, 10, and 12, respectively.

In the method of the present invention, it is preferred that CRMP comprises

• • (i) a polypeptide selected from the group consisting of SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ ID NO:10, SEQ ID NO:12 and fragments thereof, or/and
  • (ii) a polypeptide which is at least 70%, preferably at least 80%, more preferably at least 90%, even more preferably at least 95%, most preferably at least 98% identical to the polypeptide of (i).

In the method of the present invention, it is also preferred that CRMP comprises

• • (iii) a polypeptide encoded by a nucleotide sequence selected from the group consisting of SEQ ID NO:1, SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, SEQ ID NO:11, and fragments thereof,
  • (iv) a polypeptide encoded by a sequence complementary to the nucleotide sequence of (iii),
  • (v) a polypeptide encoded by a nucleic acid which is at least 70%, preferably at least 80%, more preferably at least 90%, even more preferably at least 95%, most preferably at least 98% identical to the nucleic acid of (iii) or/and (iv),
  • (vi) a polypeptide encoded by a nucleic acid corresponding to the nucleic acid of (iii), (iv) or/and
  • (v) within the scope of the degeneracy of the genetic code, or/and
  • (vii) a polypeptide encoded by a nucleic acid capable of hybridizing with the nucleic acid of (iii), (iv), (v) or/and (vi) under stringent conditions.

It is preferred that the polypeptide of (iv) encodes a polypeptide of (iii).

A preferred CRMP is CRMP-2.

Yet another preferred CRMP is a human CRMP.

It is preferred that the polypeptide of (i) is selected from SEQ ID NO: 6 and fragments thereof.

It is also preferred that the polypeptide of (iii) is encoded by a nucleotide sequence selected from SEQ ID NO:5 and fragments thereof.

Identity refers to the proportion of identical positions of two sequences (either nucleotide sequences or amino acid sequences) in the region of maximal overlap. A person skilled in the art is aware of methods for identity determination. Identity may be determined by commonly know algorithms such as FASTA or/and BLAST (in particular blastp or blastn for comparison of nucleotide or amino acid sequences; blastx for comparison of a translated nucleotide sequence with an amino acid sequence or tblastn for comparison of an amino acid sequence with a translated nucleotide sequence).

A person skilled in the art is familiar with stringent hybridization conditions (see e.g. Sambrook J. et al., 1989, Molecular Cloning, A Laboratory Manual, Cold Spring Harbor Press, Plainview, N.Y). Preferably, hybridization under stringent conditions means that, after washing for 1 h with 1×SSC and 0.1% SDS at 50° C., preferably at 55° C., more preferably at 62° C. and most preferably at 68° C., particularly for 1 h in 0.2×SSC and 0.1% SDS at 50° C., preferably at 55° C., more preferably at 62° C., and most preferably at 68° C., a positive hybridization signal is observed.

The nucleic acid fragment of the present invention preferably has a length of at least 30 nucleotides, more preferably at least 150 nucleotides, even more preferably at least 300 nucleotides, most preferably at least 600 nucleotides.

The nucleic acid fragment of the present invention preferably has a length of the natural CRMP truncated by at least 1 nucleotide, more preferably has a length of at the maximum 1500 nucleotides, even more preferably at the maximum 1200 nucleotides, most preferably at the maximum 900 nucleotides.

The polypeptide fragment of the present invention preferably has a length of at least 10 amino acids, more preferably at least 50 amino acids, even more preferably at least 100 amino acids, most preferably at least 200 amino acids.

The polypeptide fragment of the present invention preferably has a length of the natural CRMP truncated by at least 1 amino acid, more preferably has a length of at the maximum 500 amino acids, even more preferably at the maximum 400 amino acids, most preferably at the maximum 300 amino acids.

Modulation of CRMP in the context of the present invention includes the binding of a substance to CRMP or/and modulation of the biological activity of CRMP. The modulator of CRMP of the present invention may be an antagonist or may be an agonist of the biological activity of CRMP. Preferably, the modulator of CRMP is an antagonist. The biological activity may be modulated by modulation of nucleic acid activity such as transcription or/and translation, or may be modulated by modulating the activity of a translated protein. The modulator may increase or decrease the biological activity of CRMP directly or indirectly by modulation of members of the signalling cascade regulating CRMP activity, in particular of the CRMP-2 signalling cascade, such as GSK-3beta, Akt, PDK, PI3-Kinase.

The biological activity of CRMP, in particular CRMP-2, to be modulated includes, but is not limited to, spatial and temporal axogenesis and dendrite formation, formation of multiple axons by overexpression of CRMP, preferably of CRMP-2, in contrast to axons normally having a single axon and several dendrites, in particular in hippocampal neurons, suppression of axonal growth in particular in hippocampal neurons by inhibition of CRMP, preferably of CRMP-2, neuronal apoptosis, interaction with PLD₂, in particular by amino acid position 243-300 (with reference to rat CRMP-2), inhibition of PLD₂ activity, phosphorylation of CRMP, preferably of CRMP-2, dephosphorylation of CRMP, preferably of CRMP-2, activation by dephosphorylation of CRMP, preferably of CRMP-2, inactivation by phosphorylation of CRMP, preferably of CRMP-2, regulation of microtubule assembly in axons by phosphorylation/dephosphorylation, in particular by regulation of the polymerization rate by the tubulin dimer pool or/and stabilization of the microtubule polymer.

In step (a) of the present invention, the substance of the present invention is selected. The method of the present invention does not require limitations upon the substance to be selected. Any substance may be selected. Preferably, the substance is selected from compounds which have a low toxicity for mammalian cells. The substance may be an organic molecule, in particular a small organic compound with a molecular weight of at least about 50 Daltons, preferably at least about 100 Daltons, or/and at the maximum about 2,500 Daltons, preferably at the maximum about 1000 Daltons. The substance may comprise at least one functional group capable of structurally interacting with CRMP, particularly forming hydrogen bonding(s), which group may be selected from the amine, carbonyl, hydroxyl and carboxyl group. The substance may be a biomolecule, which can be selected from peptides, polypeptides, proteins, saccharides, fatty acids, steroids, purines, pyrimidines, nucleic acids including aptamers and siRNA molecules, and derivatives, structural analogs or combinations thereof.

In step (b) of the method of the present invention, the substance selected in step (a) is contacted with CRMP.

In a preferred embodiment of the method of the present invention, in step (b) the substance is contacted with isolated CRMP. In this embodiment, the method of the present invention is a molecular screening assay.

In the context of the present invention, isolated CRMP refers to CRMP partially or completely purified from a cell or/and a tissue expressing CRMP, or a cell or/and tissue lysate comprising CRMP, or a composition comprising CRMP. The cell or/and the tissue may be a natural cell or/and tissue capable of expressing CRMP, or may be a cell or/and tissue modified by recombinant DNA technology capable of expressing CRMP, in particular capable of overexpression CRMP. The cell or/and tissue may be of eukaryotic origin, or the cell may be a prokaryotic cell, preferably a gram-negative cell, such as E. coli. A person skilled in the art familiar with the amino acid sequence of CRMP or the nucleotide sequence encoding CRMP as described above is able to provide isolated CRMP by isolation from natural sources or by culturing a cell or/and tissue under conditions suitable for the expression and recovery of CRMP.

In step (b), CRMP or/and a member of the CRMP signalling cascade may be bound to a solid phase and contacted with the substance. In this event, at least the substance may be labelled, so that the label can directly or indirectly provide a detectable signal when the substance forms a complex immobilized on the solid phase via CRMP or/and a member of the CRMP signalling cascade. Alternatively, the substance may be bound to a solid phase. In this case, at least CRMP or/and a member of the CRMP signalling cascade may be labelled, so that the complex immobilized via the substance can be detected by the label. Binding on the solid phase may be irreversible or reversible by tagging CRMP, a member of the CRMP signalling cascade or/and the substance and capturing by an solid-phase bound affinity ligand specific for the tag. Suitable tag/ligand pairs are familiar to a person skilled in the art, e.g. biotin-avidin/streptavidin.

In yet another preferred embodiment of the method of the present invention, the substance is contacted in step (b) with a cell capable of expressing or overexpressing CRMP or/and with a non-human animal comprising a cell capable of expressing or overexpressing CRMP. In this embodiment, the method of the present invention is a cellular screening assay. In a preferred embodiment, in step (b), the cell is a eukaryotic cell, such as a cell line, fungal cell (e.g. yeast), an insect cell (such as Sf9), a non-human animal cell, a non-human cell line (such as CHO, COS, Hek293 or BHK), a human cell, a human cell line (such as HeLa), or a plant cell. The cell in step (b) being a eukaryotic cell may be an isolated cell. The cell in step (b) being a eukaryotic cell may be a neuronal cell, e.g. a hippocampal or a dorsal root ganglion cell, which may display neuronal polarity. The cell may comprise a complex as described herein.

Step (c) of the method of the present invention refers to determination of CRMP interaction with the substance, wherein a substance interacting with CRMP is a modulator of CRMP.

The interaction of CRMP with the substance may be a direct interaction or an indirect interaction.

A direct interaction includes complex formation. In one embodiment of the present invention, the substance may form a complex with CRMP based upon of binding, in particular specific binding, of the substance with CRMP. In a molecular screening assay, the substance may form a complex with the isolated CRMP. In a cellular screening assay, the substance may form a complex with the CRMP within the cell or/and the non-human animal.

A CRMP complex within the cell or/and the non-human animal or a complex of isolated CRMP may be detected by an antibody against CRMP or CRMP linked antigens. The antibody may be a polyclonal antibody or a monoclonal antibody, recombinant antibody, e.g. a single chain antibody, or a fragment thereof which contain at least one antigen-binding site, e.g. a proteolytic antibody fragment such as a Fab, Fab′ or F(ab′)₂ fragment or a recombinant antibody fragment such as a scFv fragment. The antibody may also be a chimeric antibody, a humanized antibody or a human antibody.

It is therefore preferred that in step (c), the determination of interaction of isolated CRMP with the substance is the determination of a complex of CRMP with the substance. In particular, the interaction of the isolated CRMP with the substance may be determined by affinity chromatography, e.g. by a pull-down assay.

In a pull-down assay, the physical interaction between two compounds can be determined. In the context of the present invention, the minimal requirement for a pull-down assay is the provision of isolated and tagged CRMP (the bait), which will be immobilized on a solid phase by the tag and used to capture and ‘pull-down’ the substance to be tested as a protein-binding partner (the prey) by release of the complex formed by bait and prey.

Classical binding assays, classical competition assays, affinity chromatography, etc, which may form part of the method of the present invention, in particular of steps (b) and (c), are familiar to a person skilled in the art.

Complex formation may also take place in a cellular screening assay. It is therefore also preferred that in step (c), the determination of interaction of CRMP with the substance within the cell or/and the non-human animal is the determination of a complex of CRMP with the substance.

In another embodiment of the present invention, the interaction of CRMP with the substance in step (c) is an indirect interaction. Indirect interactions of CRMP with the substance may be employed in a molecular screening assay or a cellular screening assay.

The indirect interaction may be mediated by GSK3beta or other members of the signalling cascade involved in the regulation of CRMP activity, in particular CRMP-2 activity. These members include but are not limited to trk receptor A, trk receptor B, trk receptor C, phosphoinositide 3 (PI3) kinase, PDK kinase, Akt kinase, glycogen synthase kinase-3β (GSK-3β). Activation of at least one of trk receptor A, trk receptor B, trk receptor C, PI3 kinase, PDK kinase, and Akt kinase result in inactivation of GSK-3β, which leads to an activation of CRMP-2 or other CRMP polypeptides. Inactivation of GSK-3β also leads to an activation of CRMP-2 or other CRMP polypeptides. Inactivation of at least one trk receptor A, trk receptor B, trk receptor C, PI3 kinase, PDK kinase, and Akt kinase result in activation of GSK-3β, which leads to an inactivation of CRMP-2 or other CRMP polypeptides. Activation of GSK-3β also leads to an inactivation of CRMP-2 or other CRMP polypeptides.

The interaction of CRMP with the substance may be determined in step (c) by modulation of the biological activity of CRMP within the cell or/and the non-human animal, in particular where, in step (b), a cell capable of expressing or overexpressing CRMP or/and a non-human animal comprising a cell capable of expressing or overexpressing CRMP is used for contacting the substance with CRMP.

Modulation of the biological activity CRMP may be caused by direct interaction. For instance, the modulation may be caused by a complex of CRMP and a substance as described herein, e.g. a compound of Formulae (I), (II), or/and (III), such as lacosamide, or a metabolite thereof. Modulation of the biological activity of CRMP may also be caused by an indirect interaction as described herein, e.g. an indirect interaction of the substance with at least one member of the signalling cascade involved in the regulation of CRMP activity, in particular CRMP-2 activity, as described herein.

Preferred biological activities of CRMP, in particular of CRMP-2, which may be modulated in the method of the present invention are described above. It is more preferred that the biological activity is neuronal polarity, i.e. a neuronal cell is capable of developing at least one axon and dendrite(s). CRMP modulation, in particular CRMP-2 modulation, may be determined by modulation of axon growth in such cells, wherein multiple axons are formed, for example, and the number of dendrites is reduced when CRMP activity, in particular CRMP-2 activity, increases, and short or no axons are formed when CRMP activity, in particular CRMP-2 activity, decreases. Suitable neuronal cell displaying neuronal polarity are hippocampal neurons, in particular cultured hippocampal neurons.

In the method of the present invention, the biological activity of CRMP may be modulated on the nucleic acid level, e.g. by modulating transcription or/and translation of CRMP or/and a member of the CRMP signalling cascade. Modulation of transcription includes a partial or complete gene inactivation, e.g. by gene disruption. Modulation also includes gene activation. Modulation of translation includes application of anti-sense molecules, ribozymes, or/and siRNA molecules. Suitable anti-sense molecules may be selected from DNA molecules, RNA molecules or nucleic acid analogues. Ribozymes may be selected from RNA molecules and nucleic acid analogues. Small RNA molecules capable of RNA interference (siRNA molecules) may be selected from RNA molecules and nucleic acid analogues. The person skilled in the art knows methods for construction of suitable anti-sense molecules or/and siRNA molecules. A suitable sequence may be selected from sequences encoding CRMP such as SEQ ID NO:1, SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, SEQ ID NO: 11, and sequences encoding CRMP signalling members, such as trk receptor A, trk receptor B, trk receptor C, PI3 kinase, PDK kinase, Akt kinase, GSK-3β, and fragments thereof.

In the method of the present invention, at least the substance may be labelled, so that the label can directly or indirectly provide a detectable signal. Alternatively, at least CRMP or/and at least one member of the CRMP signalling cascade may be labelled. Labelling of the substance, CRMP or/and at least one member of the CRMP signalling cascade can be performed by a moiety providing a detectable signal, for instance a luminescence signal, in particular a fluorescence or phosphorescence signal. Suitable dyes which can serve as luminescence labels are familiar to a person skilled in the art.

In yet another preferred embodiment, the method of the present invention is performed in a high throughput format. In this embodiment, the substances to be tested for interaction with CRMP are provided in libraries of synthetic or/and natural compounds. A person skilled in the art is aware of the technology of cellular and molecular screening assays in the high throughput format.

Yet another subject of the present invention is a cell capable of overexpressing or underexpressing CRMP or/and expressing a modified CRMP polypeptide. The cell of the present invention may be any cell capable of expressing CRMP when cultured in a suitable medium under such conditions that expression of CRMP takes place.

In a preferred embodiment, the cell is a eukaryotic cell, such as a cell line, fungal cell (e.g. yeast), an insect cell (such as Sf9), a non-human animal cell, a non-human cell line (such as CHO, COS, Hek293 or BHK), a human cell, a human cell line (such as HeLa), or a plant cell. The eukaryotic cell may be an isolated cell. More preferably, the eukaryotic cell is a neuronal cell, e.g. a hippocampal or a dorsal root ganglion cell, which may display neuronal polarity.

In another preferred embodiment, the cell is a prokaryotic cell which recombinantly expresses CRMP, more preferably a gram-negative prokaryotic cell, most preferably E. coli.

Preferably, the cell of the present invention may be a transgenic cell, i.e. a cell carrying a heterologous CRMP gene or fragment thereof.

The cell of the present invention may comprise a complex as described herein.

The cell of the present invention may be used for the provision of isolated CRMP (see above), or may be used in step (b) or/and (c) of the method of the present invention for contacting the substance selected in step (a) with CRMP.

Yet another subject of the present invention is a non-human animal comprising a cell capable of overexpressing or underexpressing CRMP or/and expressing a modified CRMP polypeptide. Preferably, the non-human animal of the present invention may be a transgenic animal, i.e. an animal carrying a heterologous CRMP gene or fragment thereof or a CRMP gene with modified nucleotide sequence i.e. point mutations modifying protein activity. The non-human animal may comprise a complex as defined herein.

CRMP, in particular CRMP-2 is naturally found in neuronal tissues, in particular during development of the central nervous system, but can also be found in peripheral tissues such as adult testis, lung tissue of fetal mouse, or monocytes (Charrier et al., Mol. Neurobiology. 2003; 28(1): 51-63). The non-human animal of the present invention may underexpress or overexpress CRMP in these cells or/and tissues. Further, the non-human animal of the present invention may express CRMP in cells or/and tissues where it is not normally expressed, such as in tissues different from neuronal tissue, adult testis, lung tissue of fetal mouse and monocytes. The non-human animal of the present invention may also express CRMP in cells or/and tissues at times where it is normally not expressed, or may underexpress CRMP in cells or/and tissues at times where it is normally expressed. Since expression of CRMP is low in adult neuronal tissue, overexpression of CRMP may be induced in adult neuronal tissue. On the other hand, CRMP may be underexpressed in developing neuronal tissue.

Non-human animals of the present invention may be obtained by homologous recombination in embryonic stem (ES) cells, where the normal locus of CRMP is mutated. Alternatively, a nucleic acid construct encoding CRMP may be injected into oocytes for randomly integrating into the genome. An ES cell line may be employed, or ES cells may be obtained freshly from a host, e.g. mouse, rat, guinea pig, etc. Construction of animals carrying recombinant DNA by ES cell manipulation is a technology familiar to a person skilled in the art.

Non-human animals of the present invention may be obtained by random mutagenesis of the animal genome, induced by the treatment with mutagenic compounds such as the chemical N-ethyl-N-nitrosourea (ENU) and a subsequent breading of animals carrying homozygous mutations in the CRMP gene locus. Random chemical mutagenesis and breeding of specific mutant animals is a technology familiar to a person skilled in the art.

If the manipulation of CRMP leads to lethality of the embryo during development, cells, tissues or/and organs of the embryo may be maintained as grafts or transplants, or by in vitro culture.

The non-human animals of the present invention may be any non-human mammal, such as a laboratory animal, domestic animals, etc, for example, mouse, rat, guinea pig, sheep, cow, pig and others.

The non-human animal of the present invention may be used for the provision of isolated CRMP (see above), or may be used in step (b) or/and (c) of the method of the present invention for contacting the substance selected in step (a) with CRMP.

As demonstrated herein, Lacosamide modulates neurotrophin-induced neuronal outgrowth. Thus, Lacosamide can thereby attenuate the induction or/and progression of neurological diseases such as epilepsy or/and neuropathic pain. Thus a compound of the present invention as described herein suitable for the prevention, alleviation or/and treatment of a CRMP associated disease, in particular Lacosamide, can have disease modifying properties when interacting with CRMP, in particular CRMP-2. This may explain the potential long-term neuroprotective effects of lacosamide.

Thus a further aspect of the present invention is a method for identification of compounds which are disease-modifying compounds or/and compound suitable for neuroprotective treatment, in particular long-term neuroprotective treatment, comprising

• • (a) selecting a substance,
  • (b) contacting the substance selected in step (a) with CRMP, and
  • (c) determining whether CRMP interacts with the substance,
    wherein a substance interacting with CRMP is a disease-modifying compound or/and a compound suitable for neuroprotective treatment, in particular long-term neuroprotective treatment. It is preferred that the disease-modifying compound or/and the compound suitable for neuroprotective treatment is suitable for treatment of a CRMP associated disease. As used in this context, “CRMP associated disease” includes the preferred CRMP associated diseases as described herein. In this context, a particularly preferred CRMP associated diseases is a neurological disease, such as epilepsy or a pain syndrome, e.g. neuropathic pain.

In the method for identification of compounds which are disease-modifying compounds or/and compound suitable for neuroprotective treatment of the present invention, the substance may be contacted in step (b) with a cell capable of expressing or overexpressing CRMP or/and with a non-human animal comprising a cell capable of expressing or overexpressing CRMP. In this embodiment, the method of the present invention is a cellular screening assay. In a preferred embodiment, in step (b), the cell is a eukaryotic cell, such as a cell line, fungal cell (e.g. yeast), an insect cell (such as Sf9), a non-human animal cell, a non-human cell line (such as CHO, COS, Hek293 or BHK), a human cell, a human cell line (such as HeLa), or a plant cell. The cell in step (b) being a eukaryotic cell may be an isolated cell. The cell in step (b) being a eukaryotic cell may be a neuronal cell, e.g. a hippocampal or a dorsal root ganglion cell, which may display neuronal polarity. The cell in step (b) may comprise a complex as described herein.

In the context of the present invention, “disease-modifying” refers to the ability of a compound to attenuate the induction or/and progression of a disease, in particular a CRMP associated disease as defined herein.

Another aspect of the present invention is the use of a compound of Formula (I), (II) or/and (III) as described herein for the manufacture of a disease-modifying medicament or/and a medicament suitable for neuroprotective treatment such as long-term neuroprotective treatment, in particular in a CRMP associated disease as described herein. As used in this context, “compound of Formula (I), (II) or/and (III)” includes the preferred compounds as described herein. A most preferred compound is lacosamide. As used in this context, “CRMP associated disease” includes the preferred CRMP associated diseases as described herein. In this context, a particularly preferred CRMP associated diseases is a neurological disease, such as epilepsy or a pain syndrome, e.g. neuropathic pain.

Yet another subject of the present invention are modulators of CRMP suitable for the prevention, alleviation or/and treatment of a CRMP-associated disease which are compounds of Formula (I)

wherein
R is hydrogen, alkyl, alkenyl, alkynyl, aryl, aryl alkyl, heterocyclic, heterocyclic alkyl, alkyl heterocyclic, cycloalkyl or cycloalkyl alkyl, and R is unsubstituted or is substituted with at least one electron withdrawing group, or/and at least one electron donating group;
R₁ is hydrogen or alkyl, alkenyl, alkynyl, aryl alkyl, aryl, heterocyclic alkyl, alkyl heterocyclic, heterocyclic, cycloalkyl, cycloalkyl alkyl, each unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group;
and
R₂ and R₃ are independently hydrogen, alkyl, alkenyl, alkynyl, alkoxy, alkoxyalkyl, aryl alkyl, aryl, halo, heterocyclic, heterocyclic alkyl, alkyl heterocyclic, cycloalkyl, cycloalkyl alkyl, or Z-Y wherein R₂ and R₃ may be unsubstituted or substituted with at least one electron withdrawing group or/and at least one electron donating group;
Z is O, S, S(O)_a, NR₄, NR′₆, PR₄ or a chemical bond;
Y is hydrogen, alkyl, aryl, aryl alkyl, alkenyl, alkynyl, halo, heterocyclic, heterocyclic alkyl, alkyl heterocyclic and Y may be unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group, provided that when Y is halo, Z is a chemical bond, or
ZY taken together is NR₄NR₅R₇, NR₄OR₅, ONR₄R₇, OPR₄R₅, PR₄OR₅, SNR₄R₇, NR₄SR₇, SPR₄R₅, PR₄SR₇, NR₄PR₅R₆, PR₄NR₅R₇ or N⁺R₅R₆R₇,

R′₆ is hydrogen, alkyl, alkenyl, or alkenyl which may be unsubstituted or substituted with at least one electron withdrawing group or/and at least one electron donating group;
R₄, R₅ and R₆ are independently hydrogen, alkyl, aryl, aryl alkyl, alkenyl, or alkynyl, wherein R₄, R₅ and R₆ may independently be unsubstituted or substituted with at least one electron withdrawing group or/and at least one electron donating group;
R₇ is R₆ or COO₈ or COR₈, which R₇ may be unsubstituted or substituted with at least one electron withdrawing group or/and at least one electron donating group;
R₈ is hydrogen or alkyl, or aryl alkyl, and the aryl or alkyl group may be unsubstituted or substituted with at least one electron withdrawing group or/and at least one electron donating group; and
n is 1-4; and
a is 1-3, or a metabolite thereof.

In a preferred embodiment, the compound of Formula (I) has the general Formula (II),

wherein

• • Ar is aryl which is unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group, preferably halo, more preferably fluoro;
  • R₁ is alkyl, preferably alkyl containing 1-3 carbon atoms, more preferably methyl; and
  • R₃ is as defined herein.

In a more preferred embodiment, the compound of Formulae (I) or/and (II) has the general Formula (III),

wherein

• • R₉ is one or more substituents independently selected from the group consisting of hydrogen, halo, alkyl, alkenyl, alkynyl, nitro, carboxy, formyl, carboxyamido, aryl, quaternary ammonium, haloalkyl, aryl alkanoyl, hydroxy, alkoxy, carbalkoxy, amino, alkylamino, dialkylamino, aryloxy, mercapto, alkylthio, alkylmercapto, and disulfide;
  • R₃ is selected from the group consisting of hydrogen, alkyl, arylalkyl, alkoxy, alkoxyalkyl, aryl, heterocyclic, heterocyclic alkyl, N-alkoxy-N-alkylamino, N-alkoxyamino, and N-carbalkoxy; and
  • R₁ is alkyl, preferably alkyl containing 1 to 3 carbon atoms, more preferably methyl.

The compounds utilized in the present invention may contain one or more asymmetric carbons and may exist in racemic and optically active forms. The configuration around each asymmetric carbon can be either the D or L form. It is well known in the art that the configuration around a chiral carbon atoms can also be described as R or S in the Cahn-Prelog-Ingold nomenclature system. All of the various configurations around each asymmetric carbon, including the various enantiomers and diastereomers as well as racemic mixtures and mixtures of enantiomers, diastereomers or both are contemplated by the present invention.

As used herein, the term configuration particularly refers to the configuration around the carbon atom to which R₂ and R₃ or H and R₃ are attached, even though other chiral centers may be present in the molecule. Therefore, when referring to a particular configuration, such as D or L, it is to be understood to mean the D or L stereoisomer at the carbon atom to which R₂ and R₃ or H and R₃ are attached. However, it also includes all possible enantiomers and diastereomers at other chiral centers, if any, present in the compound.

The compounds of the present invention are directed to all the optical isomers, i.e., the compounds of the present invention are either the L-stereoisomer or the D-stereoisomer (at the carbon atom to which R₂ and R₃ or H and R₃ are attached). These stereoisomers may be found in mixtures of the L and D stereoisomer, e.g., racemic mixtures. The D stereoisomer is preferred.

It is preferred that the compounds of Formula (I) are in the R configuration. It is also preferred that the compounds of Formula (II) are in the R configuration. It is also preferred that the compounds of Formula (III) are in the R configuration.

It is preferred that the compounds of Formulae (I), (II) or/and (III) in the R configuration are substantially enantiopure. As used herein, the term “substantially enantiopure” refers to a content of the R enantiomer of at least 99.5%. This corresponds to an enantiomeric excess, (ee) of 99%. The respective quantities of R and S enantiomer may be determined by chiral column chromatography, e.g. by HPLC with “ChiralPak” as chiral, stationary phase.

The term “alkyl” (alone or in combination with another term(s)) means a straight- or branched-chain saturated hydrocarbyl substituent preferably containing from 1 to about 20 carbon atoms (C₁-C₂₀-alkyl), more preferably from 1 to about 8 carbon atoms (C₁-C₈-alkyl), even more preferably from 1 to about 6 carbon atoms (C₁-C₆-alkyl), and most preferably from 1 to 3 carbon atoms (C₁-C₃-alkyl). The alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, amyl, hexyl, and the like. Further, alkyl groups also include halogenated alkyl groups up to perhalogenation, e.g. trifluoromethyl, if not indicated otherwise.

The term “alkoxy” (alone or in combination with another term(s)) refers to —O-alkyl and means a straight- or branched-chain alkoxy substituent preferably containing from 1 to about 20 carbon atoms (C₁-C₂₀-alkoxy), more preferably from 1 to about 8 carbon atoms (C₁-C₈-alkoxy), even more preferably from 1 to about 6 carbon atoms (C₁-C₆-alkoxy), and most preferably from 1 to 3 carbon atoms (C₁-C₃-alkoxy). The alkoxy groups include methoxy, ethoxy, propoxy, butoxy, isobutoxy, tert-butoxy, pentoxy, hexoxy and the like. Further, alkoxy groups include halogenated alkoxy groups up to perhalogenation, if not indicated otherwise.

The term “alkoxyalkyl” refers to an alkyl group substituted with at least one alkoxy group. The alkoxyalkyl groups include methoxymethyl (—CH₂—OCH₃) groups, methoxyethyl (—CH₂—CH₂—OCH₃) groups, ethoxymethyl (—CH₂—O—CH₂CH₃) groups and the like.

The term “N-alkoxyamino” refers to amino groups substituted with one or two alkoxy groups, e.g. —NH—N(OCH₃)₂.

The term “N-alkoxy-N-alkylamino” refers to amino groups substituted with an alkoxy group and an alkyl group, e.g. —N(CH₃)(OCH₃), —N(CH₃)(OCH₂—CH₃) and the like.

The term “N-carbalkoxy” refers to amino groups substituted with a carbalkoxy group, e.g. —NH(C(O)—O—CH₃), —NH(C(O)O—CH₂—CH₃).

The term “aryl”, when used alone or in combination with other term(s), refers to an aromatic group which contains from 6 up to 18 ring carbon atoms (C₆-C₁₈-aryl), preferably from 6 up to 10 ring carbon atoms (C₆-C₁₀-aryl), and includes polynuclear aromatics. The aryl groups may be monocyclic, bicyclic, tricyclic or polycyclic and may be fused rings. A polynuclear aromatic compound as used herein, is meant to encompass bicyclic and tricyclic fused aromatic ring systems containing from 10-18 ring carbon atoms. Aryl groups include phenyl and polynuclear aromatics e.g., naphthyl, anthracenyl, phenanthrenyl, azulenyl and the like. The aryl group also includes groups such as ferrocenyl. Aryl groups may be unsubstituted or mono or polysubstituted with electron withdrawing or/and electron donating groups. A preferred aryl group is phenyl, which may unsubstituted or mono or polysubstituted with electron withdrawing or/and electron donating groups.

The term “aryl alkyl” as used herein alone or in combination with other term (s) means an alkyl group as defined herein carrying an aryl substitutent as defined herein. Preferred aryl alkyl groups are aryl-C₁-C₆-alkyl, aryl-C₁-C₃-alkyl, C₆-C₁₀-aryl-alkyl, C₆-C₁₀-aryl-C₁-C₆-alkyl, C₆-C₁₀-aryl-C₁-C₃-alkyl. More preferred aryl alkyl groups are phenyl-C₁-C₆-alkyl and phenyl-C₁-C₃-alkyl. Even more preferred aryl alkyl groups include, for example, benzyl, phenylethyl, phenylpropyl, phenylisopropyl, phenylbutyl, diphenylmethyl, 1,1-diphenylethyl, 1,2-diphenylethyl, and the like. Most preferred is benzyl.

The term “alkenyl” (alone or in combination with another term(s)) means a straight- or branched-chain alkenyl substituent containing at least one double bond and preferably containing from 2 to about 20 carbon atoms (C₂-C₂₀-alkenyl), more preferably from 2 to about 8 carbon atoms (C₂-C₈-alkenyl), and even more preferably from 2 to about 6 carbon atoms (C₂-C₆-alkenyl), most preferably 2 or 3 carbon atoms (C₂-C₃-alkenyl). The alkenyl group may be in the Z or E form. Alkenyl groups include vinyl, propenyl, 1-butenyl, isobutenyl, 2-butenyl, 1-pentenyl, (Z)-2-pentenyl, (E)-2-pentenyl, (Z)-4-methyl-2-pentenyl, (E)-4-methyl-2-pentenyl, pentadienyl, e.g., 1, 3 or 2,4-pentadienyl, and the like.

The term “alkynyl” (alone or in combination with another term(s)) means a straight- or branched-chain alkynyl substituent containing at least one triple bond and preferably containing from 2 to about 20 carbon atoms (C₂-C₂₀-alkynyl), more preferably from 2 to about 8 carbon atoms (C₂-C₈-alkynyl), and even more preferably from 2 to about 6 carbon atoms (C₂-C₆-alkynyl), most preferably 2 or 3 carbon atoms (C₂-C₃-alkynyl). The alkynyl group includes ethynyl, propynyl, 1-butynyl, 2-butynyl, 1-pentynyl, 2-pentynyl, 3-methyl-1-pentynyl, 3-pentynyl, 1-hexynyl, 2-hexynyl, 3-hexynyl and the like.

The term “cycloalkyl” when used alone or in combination with another term (s) means a cycloalkyl group containing from 3 to 18 ring carbon atoms (C₃-C₁₈-cycloalkyl), preferably from 6 up to 10 ring carbon atoms (C₃-C₁₀-cycloalkyl). The cycloalkyl groups may be monocyclic, bicyclic, tricyclic, or polycyclic, and the rings may be fused. The cycloalkyl may be completely saturated or partially saturated. Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, cyclohexenyl, cyclopentenyl, cyclooctenyl, cycloheptenyl, decalinyl, hydroindanyl, indanyl, fenchyl, pinenyl, adamantyl, and the like. The cycloalkyl group includes the cis or trans forms. Cycloalkyl groups may be unsubstituted or mono or polysubstituted with electron withdrawing or/and electron donating groups. In a bridged bicyclic cycloalkyl group, the substituents may either be in endo or exo positions.

The term “cycloalkyl alkyl” as used herein alone or in combination with other term(s) means an alkyl group as defined herein carrying a cycloalkyl substitutent as defined herein. Preferred cycloalkyl alkyl groups are cycloalkyl-C₁-C₆-alkyl, cycloalkyl-C₁-C₃-alkyl, C₆-C₁₀-cycloalkyl-alkyl, C₆-C₁₀-cycloalkyl-C₁-C₆-alkyl, C₆-C₁₀-cycloalkyl-C₁-C₃-alkyl. A more preferred cycloalkyl alkyl group is selected from cyclohexyl-C₁-C₆-alkyl and cyclohexyl-C₁-C₃-alkyl.

The term “halo” or “halogen” includes fluoro, chloro, bromo, and iodo.

The prefix “halo” indicates that the substituent to which the prefix is attached is substituted with one or more independently selected halogen radicals. For example, haloalkyl means an alkyl substituent wherein at least one hydrogen radical is replaced with a halogen radical. Examples of haloalkyls include chloromethyl, 1-bromoethyl, fluoromethyl, difluoromethyl, trifluoromethyl, 1,1,1-trifluoroethyl, and the like. Illustrating further, “haloalkoxy” means an alkoxy substituent wherein at least one hydrogen radical is replaced by a halogen radical. Examples of haloalkoxy substituents include chloromethoxy, 1-bromoethoxy, fluoromethoxy, difluoromethoxy, trifluoromethoxy (also known as “perfluoromethyloxy”), 1,1,1,-trifluoroethoxy, and the like. It should be recognized that if a substituent is substituted by more than one halogen radical, those halogen radicals may be identical or different (unless otherwise stated).

The terms “electron-withdrawing” and “electron donating” refer to the ability of a substituent to withdraw or donate electrons, respectively, relative to that of hydrogen if the hydrogen atom occupied the same position in the molecule. These terms are well understood by one skilled in the art and are discussed in Advanced Organic Chemistry, by J. March, John Wiley and Sons, New York, N.Y., pp. 16-18 (1985) and the discussion therein is incorporated herein by reference. Electron withdrawing groups include halo, including bromo, fluoro, chloro, iodo; nitro, carboxy, alkenyl, alkynyl, formyl, carboxyamido, aryl, quaternary ammonium, haloalkyl such as trifluoromethyl, aryl alkanoyl, carbalkoxy and the like. Electron donating groups include such groups as hydroxy, alkoxy, including methoxy, ethoxy and the like; alkyl, such as methyl, ethyl, and the like; amino, alkylamino, dialkyl amino, aryloxy such as phenoxy, mercapto, alkylthio, alkylmercapto, disulfide (alkyldithio) and the like. One of ordinary skill in the art will appreciate that some of the aforesaid substituents may be considered to be electron donating or electron withdrawing under different chemical conditions. Moreover, the present invention contemplates any combination of substituents selected from the above-identified groups.

The electron donating or/and electron withdrawing groups may independently be present in any one of the substituents in Formula (I), (II) or/and (III) e.g., in R, R₁, R₂, R₃, R₄, R₅, R₆, R′₆, R₇, R₈, R₉ or/and R₁₀ as defined herein.

The at least one electron withdrawing or/and at least one electron donating group is preferably selected independently from halo, alkyl, alkenyl, alkynyl, nitro, carboxy, formyl, carboxyamido, aryl, quaternary ammonium, haloalkyl, aryl alkanoyl, hydroxy, alkoxy, carbalkoxy, amino, alkylamino, dialkylamino, aryloxy, mercapto, alkylthio, alkylmercapto, disulfide, alkanoyl, amino alkyl, aryloyl, cyano, sulfonyl, sulfoxide, heterocyclic, guanidine, sulfonium salts, mercaptoalkyl, and alkyldithio.

The term “sulfide” encompasses mercapto, mercapto alkyl and alkylthio, while the term disulfide encompasses alkyldithio.

In the compounds of the present invention, the at least one electron withdrawing or/and at least one electron donating group is more preferably selected independently from halo, alkyl, alkenyl, alkynyl, nitro, carboxy, formyl, carboxyamido, aryl, quaternary ammonium, haloalkyl, aryl alkanoyl, hydroxy, alkoxy, carbalkoxy, amino, alkylamino, dialkylamino, aryloxy, mercapto, alkylthio, alkylmercapto, and disulfide.

Even more preferably, the at least one electron withdrawing or/and at least one electron donating group is selected from halo, C₁-C₆-alkyl, C₂-C₆-alkenyl, C₁-C₆-alkynyl, nitro, carboxy, formyl, carboxyamido, C₆-C₁₀-aryl, quaternary ammonium, C₁-C₆-haloalkyl, C₆-C₁₀-aryl C₂-C₆-alkanoyl, hydroxy, C₁-C₆-alkoxy, C₂-C₆-carbalkoxy, amino, C₁-C₆-alkylamino, C₁-C₆-dialkylamino, C₆-C₁₀-aryloxy, mercapto, C₁-C₆-alkylthio, C₁-C₆-alkylmercapto, and disulfide.

Even more preferably, the electron withdrawing or/and electron donating groups may also be independently selected from halo, C₁-C₆-alkoxy, nitro, carboxy, formyl, carboxyamido, quaternary ammonium, hydroxy, amino, mercapto, and disulfide.

Most preferred electron withdrawing or/and electron donating groups are independently selected from halo such as fluoro and C₁-C₆-alkoxy such as methoxy and ethoxy.

The term “carbalkoxy” as used herein alone or in combination with other term(s) means an —CO—O-alkyl, wherein alkyl is as defined herein, taking into account that the —CO—O— group provides one carbon atom in addition to those of the alkyl group. The carbalkoxy group preferably contains from 2 to about 20 carbon atoms (C₂-C₂₀-carbalkoxy), more preferably from 2 to about 8 carbon atoms (C₂-C₈-carbalkoxy), even more preferably from 2 to about 6 carbon atoms (C₂-C₆-carbalkoxy), and most preferably from 2 to 3 carbon atoms (C₂-C₃-carbalkoxy).

The term “alkanoyl” as used herein alone or in combination with other term (s) means an alkanoyl group —CO-alkyl, wherein alkyl is as defined herein, taking into account that the —CO— group provides one carbon atom in addition to those of the alkyl group. The alkanoyl preferably contains from 2 to about 20 carbon atoms (C₂-C₂₀-alkanoyl), more preferably from 2 to about 8 carbon atoms (C₂-C₈-alkanoyl), even more preferably from 2 to about 6 carbon atoms (C₂-C₆-alkanoyl), and most preferably from 2 to 3 carbon atoms (C₂-C₃-alkanoyl). The alkanoyl group may be straight chained or branched. The alkanoyl groups include, for example, formyl, acetyl, propionyl, butyryl, isobutyryl, tertiary butyryl, pentanoyl and hexanoyl.

As employed herein, a heterocyclic group contains at least one heteroatom in the cyclic structure, preferably one, two, three or four heteroatoms. The at least one heteroatom may be independently selected from sulfur, nitrogen and oxygen. The heterocyclic groups contemplated by the present invention include heteroaromatics and saturated and partially saturated heterocyclic groups. The heterocyclics may be monocyclic, bicyclic, tricyclic or polycyclic and may be fused rings. The heterocyclics also include the so-called benzoheterocyclics. Heterocyclic groups may be unsubstituted or mono or polysubstituted with electron withdrawing or/and electron donating groups. The heterocyclic groups preferably contain up to 18 ring atoms and up to a total of 17 ring carbon atoms and may be unsubstituted or mono or polysubstituted with electron withdrawing or/and electron donating groups.

More preferably, the heterocyclic group may be independently selected from 5 or 6-membered monocyclic heterocyclic groups and may be unsubstituted or mono or polysubstituted with electron withdrawing or/and electron donating groups. The heterocyclic group may also be more preferably selected independently from furyl, thienyl, pyrazolyl, pyrrolyl, methylpyrrolyl, imidazolyl, indolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, piperidyl, pyrrolinyl, piperazinyl, quinolyl, triazolyl, tetrazolyl, isoquinolyl, benzofuryl, benzothienyl, morpholinyl, benzoxazolyl, tetrahydrofuryl, pyranyl, indazolyl, purinyl, indolinyl, pyrazolindinyl, imidazolinyl, imadazolindinyl, pyrrolidinyl, furazanyl, N-methylindolyl, methylfuryl, pyridazinyl, pyrimidinyl, pyrazinyl, pyridyl, epoxy, aziridino, oxetanyl, azetidinyl, the N-oxides of the nitrogen containing heterocycles, such as the N-oxides of pyridyl, pyrazinyl, and pyrimidinyl and the like. Even more preferably, the heterocyclic moieties are those aforementioned heterocyclics which are monocyclic.

The heterocyclics may also be more preferably selected independently from thienyl, furyl, pyrrolyl, benzofuryl, benzothienyl, indolyl, oxazolyl, methylpyrrolyl, morpholinyl, pyridiyl, pyrazinyl, imidazolyl, pyrimidinyl, and pyridazinyl. Especially preferred heterocyclic are independently selected from furyl, oxazolyl, pyridyl, pyrazinyl, imidazolyl, pyrimidinyl, and pyridazinyl. The most preferred heterocyclics are independently selected from furyl, pyridyl and oxazolyl.

The monocyclic 5- or 6-membered heterocyclic groups in the compounds of the present invention are preferably of the Formula (IV):

or those corresponding partially or fully saturated form thereof, wherein n is 0 or 1; and
R₅₀ is H, an electron withdrawing group or an electron donating group;
A, E, L, J and G are independently CH, or a heteroatom selected from the group consisting of N, O, S; but when n is O, G is CH, or a heteroatom selected from the group consisting of NH, O and S with the proviso that at most two of A, E, L, J and G are heteroatoms.

When n is 0, the above heteroaromatic moiety is a five membered ring, while if n is 1, the heterocyclic moiety is a six membered monocyclic heterocyclic moiety.

If the ring depicted in Formula (IV) contains a nitrogen ring atom, then the N-oxide forms are also contemplated to be within the scope of the invention.

When R₂ or R₃ is a heterocyclic of Formula (IV), it may be bonded to the main chain by a ring carbon atom. When n is 0, R₂ or R₃ may additionally be bonded to the main chain by a nitrogen ring atom.

The term “heterocyclic alky” as used herein alone or in combination with other term(s) means an alkyl group as defined above carrying a heterocyclic substituent as defined above. Preferred heterocyclic alkyl groups are heterocyclic-C₁-C₆-alkyl, heterocyclic-C₁-C₃-alkyl, wherein the heterocyclic may be a preferred, more preferred or most preferred heterocyclic group as defined herein.

The term “alkyl heterocyclic” as used herein alone or in combination with other term(s) means a heterocyclic group as defined above carrying at least one alkyl substituent as defined above. Preferred alkyl heterocyclic groups are C₁-C₆-alkyl-heterocyclic, C₁-C₃-alkyl-heterocyclic, wherein the heterocyclic group may be a preferred, more preferred or most preferred heterocyclic group as defined herein.

The preferred compounds are those wherein n is 1, but di (n=2), tri (n=3) and tetrapeptides (n=4) are also contemplated to be within the scope of the invention.

In the ZY groups representative of R₂ or/and R₃, in the formula (I) or/and (II), Z may be O, S, S(O)_a, wherein a is 1-3, NR₄, NR′₆, PR₄ or a chemical bond; and Y may be hydrogen, alkyl, aryl, aryl alkyl, alkenyl, alkynyl, halo, heterocyclic, heterocyclic alkyl, alkyl heterocyclic, and Y may be unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group, provided that when Y is halo, Z is a chemical bond, or

ZY taken together may be NR₄NR₅R₇, NR₄OR₅, ONR₄R₇, OPR₄R₅, PR₄OR₅, SNR₄R₇, NR₄SR₇, SPR₄R₅, PR₄SR₇, NR₄PR₅R₆, PR₄NR₅R₇ or N⁺R₅R₆R₇,

wherein R₄, R₅, R′₆, R₆, R₇, are as defined herein.

The ZY groups representative of R₂ or/and R₃ in the Formula (I) or/and (II) may be hydroxy, alkoxy, such as methoxy, ethoxy, aryloxy, such as phenoxy; thioalkoxy, such as thiomethoxy, thioethoxy; thioaryloxy such as thiophenoxy; amino; alkylamino, such as methylamino, ethylamino; arylamino, such as anilino; dialkylamino, such as, dimethylamino; trialkyl ammonium salt, hydrazino; alkylhydrazino and arylhydrazino, such as N-methylhydrazino, N-phenylhydrazino, carbalkoxy hydrazino, aralkoxycarbonyl hydrazino, aryloxycarbonyl hydrazino, hydroxylamino, such as N-hydroxylamino (—NH—OH), alkoxy amino [(NHOR₁₈) wherein R₁₈ is alkyl], N-alkylhydroxylamino [(NR₁₈)OH wherein R₁₈ is alkyl], N-alkyl-O-alkylhydroxyamino, i.e., [N(R₁₈)OR₁₉ wherein R₁₈ and R₁₈ are independently alkyl], and O-hydroxylamino (—O—NH₂); alkylamido such as acetamido; trifluoroacetamido; alkoxyamino, (e.g., NH(OCH₃); and heterocyclicamino, such as pyrazoylamino.

In a preferred ZY group, Z is O, NR₄ or PR₄; Y is hydrogen or alkyl.

In another preferred embodiment,

In a more preferred that ZY is NR₄OR₅, or ONR₄R₇.

Another more preferred ZY is N-hydroxyamino, N-alkylhydroxyamino, N-alkyl-O-alkyl hydroxyamino, O-alkylhydroxyamino, N-alkoxy-N-alkylamino, N-alkoxyamino, or N-carbalkoxy.

In Formula (I), R is preferably aryl or aryl alkyl, more preferably R is aryl alkyl, wherein R is unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group. R may be phenyl or benzyl, most preferably benzyl, wherein R is unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group. If R is substituted, R is preferably substituted on the aryl ring. In this embodiment, the at least one electron donating group or/and at least one electron withdrawing group is preferably halo, more preferably fluoro.

In Formulae (I), (II) or/and (III), R₁ is H or alkyl. More preferably, R₁ is alkyl, preferably containing from 1 to 6 carbon atoms, more preferably containing from 1 to 3 carbon atoms. Most preferably the R₁ group is methyl. R₁ may be unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group.

Further, it is preferred that one of R₂ and R₃ is hydrogen. It is more preferred that R₂ is hydrogen. Other preferred moieties of R₂ in Formula (I) are aryl such as phenyl, aryl alkyl such as benzyl, and alkyl. It is to be understood that the preferred groups of R₂ may be unsubstituted or mono or poly substituted with electron donating or/and electron withdrawing groups. It is preferred that the at least one electron withdrawing or/and at least one donating group in R₂ is independently alkoxy, N-hydroxyamino, N-alkylhydroxyamino, N-alkyl-O-alkyl hydroxyamino or O-alkylhydroxyamino, and especially methoxy or ethoxy.

In Formulae (I), (II) or/and (III), R₃ may be hydrogen, an alkyl group unsubstituted or substituted by at least an electron donating or/and at least one electron withdrawing group, an aryl group unsubstituted or substituted by at least an electron donating or/and at least one electron withdrawing group heterocyclic, heterocyclic alkyl, or ZY.

It is preferred that R₃ is hydrogen, alkyl unsubstituted or substituted by at least an electron donating or/and at least one electron withdrawing group, aryl which is unsubstituted or substituted by at least one electron donating group or/and at least one electron withdrawing group, heterocyclic, heterocyclic alkyl or ZY, wherein Z is O, NR₄ or PR₄; Y is hydrogen or alkyl;

It is also preferred that R₃ is alkyl unsubstituted or substituted by at least an electron donating or/and at least one electron withdrawing group; or Z-Y,
wherein Z-Y is as defined herein.

It is also preferred that R₃ is alkyl unsubstituted or substituted by at least an electron donating or/and at least one electron withdrawing group; NR₄OR₅, or ONR₄R₇, wherein R₄, R₅ and R₇ are as defined herein.

It is also preferred that R₃ is CH₂-Q, wherein Q is alkoxy especially containing 1-3 carbon atoms; or R₃ is NR₄OR₅ or ONR₄R₇, wherein R₄, R₅, and R₇ are as defined herein.

R₃ is also preferably alkyl which is unsubstituted or substituted with at least one alkoxy especially containing 1-3 carbon atoms.

R₃ is also preferably CH₂-Q, wherein Q is alkoxy preferably containing 1-3 carbon atoms, more preferably Q is ethoxy or methoxy.

R₃ is also preferably NR₄OR₅, or ONR₄R₇, wherein R₄, R₅ and R₇ are as defined herein, and R₄, R₅ and R₇ are as defined herein, e.g. N-alkoxy, N-alkoxy-N-alkylamino or N-carbalkoxy.

R₃ is also preferably heterocyclic, heterocyclic alkyl, or aryl, which may be unsubstituted or substituted with at least an electron donating or/and at least one electron withdrawing group. A most preferred heterocyclic in R₃ is furyl or oxazolyl.

R₃ is also preferably selected from the group consisting of hydrogen, alkyl, arylalkyl such as benzyl, alkoxy, alkoxyalkyl, aryl such as phenyl, heterocyclic, heterocyclic alkyl, N-alkoxy-N-alkylamino, N-alkoxyamino and N-carbalkoxy.

It is to be understood that the preferred groups of R₃ may be unsubstituted or mono or poly substituted with electron donating or/and electron withdrawing groups. It is preferred that the at least one electron withdrawing or/and at least one electron donating group in R₃ is independently alkoxy, N-hydroxyamino, N-alkylhydroxyamino, N-alkyl-O-alkyl hydroxyamino or O-alkylhydroxyamino, and especially methoxy or ethoxy.

R₄, R₅, R₆, R′₆, R₇ and R₈ are preferably independently hydrogen or alkyl.

R₄, R₅, and R₇ are preferably independently hydrogen or alkyl preferably containing 1-3 carbon atoms.

The most preferred aryl is phenyl. The most preferred halo is fluoro.

In the compounds of Formula (I), R is preferably aryl alkyl, wherein R is unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group.

In the compounds of Formula (I), R₁ is preferably alkyl which is unsubstituted or substituted with at least one electron donating group or/and at least one electron withdrawing group.

In the compounds of Formula (I), R₂ and R₃ is preferably independently hydrogen, alkyl which is unsubstituted or substituted by at least one electron donating group or/and at least one electron withdrawing group, aryl which is unsubstituted or substituted by at least one electron donating group or/and at least one electron withdrawing group, heterocyclic, heterocyclic aryl, or ZY; wherein Z is O, NR₄ or PR₄; and Y is hydrogen or

wherein R₄, R₅ and R₇ are as defined herein.

In the compounds of Formula (I), the preferred groups of R₂ and R₃ may be unsubstituted or mono or poly substituted with electron donating or/and electron withdrawing groups, such as alkoxy (e.g., methoxy, ethoxy, and the like), N-hydroxyamino, N-alkylhydroxyamino, N-alkyl-O-alkyl hydroxyamino and O-alkylhydroxyamino.

In the compounds of Formula (I), the at least one electron donating group or/and at least one electron withdrawing group in R₂ or/and R₃ is preferably independently hydroxy or alkoxy.

It is more preferred that in the compounds of Formula (I), R₂ is hydrogen.

In the compounds of Formula (II), R₁ is preferably methyl.

In preferred compounds of Formula (II), R₃ is hydrogen or alkyl unsubstituted or substituted by at least one electron donating group or/and at least one electron withdrawing group; or R₃ is heterocyclic, heterocyclic alkyl, or Z-Y, wherein Z-Y and heterocyclic are as defined herein.

In other preferred compounds of Formula (II), R₃ is an alkyl group which is unsubstituted or substituted by at least one electron donating group or/and at least one electron withdrawing group, NR₄OR₅ or ONR₄R₇, wherein R₄, R₅ and R₇ are as defined herein and wherein the at least one electron donating group or/and at least one electron withdrawing group is preferably selected from hydroxy and alkoxy.

In further preferred compounds of Formula (II), R₃ is CH₂-Q, wherein Q is alkoxy preferably containing 1-3 carbon atoms, more preferably methoxy, or

R₃ is NR₄OR₅ or ONR₄R₇ wherein R₄, R₅ and R₇ are independently hydrogen or alkyl containing 1-3 carbon atoms.

In other preferred compounds of Formula (II), R₃ is —CH₂-Q, wherein Q is alkoxy containing 1 to 3 carbon atoms.

In the compounds of Formula (II), Ar is preferably phenyl unsubstituted or substituted with at least one halo, preferably with at least one fluoro. More preferably Ar in Formula (II) is unsubstituted phenyl.

In preferred compounds of Formula (III), R₉ is hydrogen or fluoro, R₃ is selected from the group consisting of methoxymethyl, phenyl, N-methoxy-N-methylamino, and N-methoxyamino, and R₁ is methyl.

The most preferred compounds of the present invention include:

• (R)-2-acetamido-N-benzyl-3-methoxy-propionamide;
• (R)-2-acetamido-N-benzyl-3-ethoxy-propionamide;
• O-methyl-N-acetyl-D-serine-m-fluorobenzyl-amide;
• O-methyl-N-acetyl-D-serine-p-fluorobenzyl-amide;
• N-acetyl-D-phenylglycine benzylamide;
• D-1,2-(N,O-dimethylhydroxylamino)-2-acetamide acetic acid benzylamide;
• D-1,2-(O-methylhydroxylamino)-2-acetamido acetic acid benzylamide;
• D-α-acetamido-N-(2-fluorobenzyl)-2-furanacetamide;
• D-α-acetamido-N-(3-fluorobenzyl)-2-furanacetamide.

It is to be understood that the various combinations and permutations of the Markush groups of R₁, R₂, R₃, R and n described herein are contemplated to be within the scope of the present invention. Moreover, the present invention also encompasses compounds and compositions which contain one or more elements of each of the Markush groupings in R₁, R₂, R₃, n and R and the various combinations thereof. Thus, for example, the present invention contemplates that R₁ may be one or more of the substituents listed hereinabove in combination with any and all of the substituents of R₂, R₃, and R with respect to each value of n.

More preferred is a compound of Formula (I), (II) or/and (III) in the R configuration, preferably substantially enantiopure, wherein the substituent R is benzyl which is unsubstituted with at least one halo group, wherein R₃ is CH₂-Q, wherein Q is alkoxy containing 1-3 carbon atoms and wherein R₁ is methyl. Preferably R is unsubstituted benzyl or benzyl substituted with at least one halo group which is a fluoro group.

Depending upon the substituents, the present compounds may form addition salts as well. All of these forms are contemplated to be within the scope of this invention including mixtures of the stereoisomeric forms.

The manufacture of compounds utilized in the present invention is described in U.S. Pat. Nos. 5,378,729 and 5,773,475, and in the international application PCT/EP 2005/010603 the contents of which are incorporated by reference.

The compounds utilized in the present invention are useful as such as depicted in the Formulae (I), (II) or/and (III) or can be employed in the form of salts in view of its basic nature by the presence of the free amino group. Thus, the compounds of Formulae (I), (II) or/and (III) form salts with a wide variety of acids, inorganic and organic, including pharmaceutically acceptable acids. The salts with therapeutically acceptable acids are of course useful in the preparation of formulation where enhanced water solubility is most advantageous.

These pharmaceutically acceptable salts have also therapeutic efficacy. These salts include salts of inorganic acids such as hydrochloric, hydroiodic, hydrobromic, phosphoric, metaphosphoric, nitric acid and sulfuric acids as well as salts of organic acids, such as tartaric, acetic, citric, malic, benzoic, perchloric, glycolic, gluconic, succinic, aryl sulfonic, (e.g., p-toluene sulfonic acids, benzenesulfonic), phosphoric, malonic, and the like.

Yet another subject of the present invention is a complex comprising CRMP, in particular CRMP-2, and a compound of Formulae (I), (II), or/and (III) as defined herein, a pharmaceutically acceptable salt or a metabolite thereof, wherein the compound or metabolite thereof exhibits an affinity for the CRMP polypeptide, in particular the CRMP-2 polypeptide, characterized by a K_D less than about 5 μM. It is preferred that the complex comprises CRMP, in particular CRMP-2, and lacosamide. In the complex of the present invention, CRMP and CRMP-2 are as defined herein.

The complex of the present invention may be an isolated complex.

Yet another aspect of the present invention is a method for preparing a complex of the present invention, comprising contacting CRMP, in particular CRMP-2, with a compound of Formulae (I), (II), or/and (III) as defined herein, in particular lacosamide, a pharmaceutically acceptable salt or a metabolite thereof having an affinity for the CRMP polypeptide, in particular the CRMP-2 polypeptide, characterized by a K_D less than about 5 μM. In the method for preparing a complex of the present invention, CRMP, in particular CRMP-2 are as defined herein.

In the method for preparing a complex of the present invention, the CRMP, in particular the CRMP-2, may be in a cell and the compound or metabolite thereof may be delivered to the cell and absorbed by the cell. The cell may be a cell as described herein, for instance a neuronal cell, which cell may be capable of overexpressing CRMP, in particular CRMP-2.

Yet another aspect of the present invention is a diagnostic method of a CRMP-associated disease, comprising:

• • (a) contacting a biological sample of a subject with a compound of formula (I), (II), or/and (III) as defined herein, a pharmaceutically acceptable salt or a metabolite thereof having an affinity for CRMP, in particular CRMP-2, characterized by K_D less than about 5 μM, and thereafter
  • (b) assaying the biological sample for a complex of the present invention,
    wherein detection of said complex is indicative of CRMP mediation of the disease and of utility of the compound of formula (I), (II), or/and (III) as defined herein, a pharmaceutically acceptable salt or a metabolite thereof in treatment of the disease. In the diagnostic method, CRMP2, in particular CRMP-2 are as defined herein.

The biological sample may comprise a cell, a tissue, or/and a body fluid obtained from a subject suspected to suffer from a CRMP-associated disease as described herein.

In the diagnostic method of the present invention, the compound of formula (I), (II), or/and (III) may be lacosamide. The disease to be diagnosed by the diagnostic method of the present invention may be a CRMP associated disease as described herein.

Yet another aspect of the present invention is a method for the prevention, alleviation or/and treatment of a CRMP-associated disease in a subject, the method comprising administering to the subject a compound of formula (I), (II), or/and (III) as defined herein, a pharmaceutically acceptable salt or a metabolite thereof, wherein, following said administering, a complex of the present invention is formed in a cell or tissue of an organ of the subject affected by the disease. The compound to be administered may be lacosamide. In the method for the prevention, alleviation or/and treatment of a CRMP-associated disease, CRMP, in particular CRMP-2, are as defined herein.

The CRMP-associated disease may be a disease as defined herein. The disease may be as neurological and the complex is formed in a neuronal cell or tissue. In one embodiment, the CRMP-2 mediated disease is selected from the group consisting of epilepsy, pain syndromes, motoneuron disorders, dyskinesias, tremor syndromes, schizophrenia and combinations thereof. The CRMP-2 mediated disease may be an epilepsy condition, which may be selected from the group consisting of complex partial seizures, status epilepticus, acute repetitive seizures and seizure clusters. The present application claims the priorities of EP 06 021 470.7 filed on 12 Oct. 2006, EP 06 021 469.9 filed on 12 Oct. 2006, EP 06 013 655.3 filed on 30 Jun. 2006 and EP 06 024 241.9 filed on 22 Nov. 2006, the disclosures of which are incorporated herein by reference.

The invention is further illustrated by the following figures and examples. The examples present evidence that Lacosamide binds directly to CRMP-2.

FIGURE LEGENDS

FIG. 1 describes the axon length after treatment by lacosamide. Stimulation of hippocampal primary cells by Lacosamide (1-200 μM) does not significantly change basal axonal outgrowth.

FIG. 2 describes the axon length after stimulation with 50 ng/ml NT3 and treatment with Lacosamide (Lac) or the kinase inhibitor Wortmannin (Wort). Treatment of neurons with 50 ng/ml NT3 increases axonal outgrowth. Treatment with 100 μM Lacosamide (Lac) or 400 nM of the positive control Wortmannin (Wort) significantly decreases NT3-induced axonal growth.

FIG. 3 describes Axon length after stimulation with 200 ng/ml BDNF and treatment with Lacosamide (Lac) or the kinase inhibitor Wortmannin (Wort). Treatment of neurons with 200 ng/ml BDNF significantly increases axonal outgrowth. Treatment with 1 μM and 100 μM Lacosamide (Lac) or 200 nM and 400 nM of the positive control Wortmannin (Wort) significantly decreases BDNF-induced axonal growth.

FIG. 4 gives an overview upon CRMP-2 amino acid sequence identity among various vertebrate species (at least 87% identical to the human CRMP-2 sequence). In the mammalian species considered, the CRMP-2 sequences are at least 98% identical to the human CRMP-2 sequence.

FIG. 5 shows the surviving rates of neuronal embryonic stem cell derivates after excitotoxic insult. After treatment with 200 μM NMDA, survival rate is 15.6%. After treatment with 100 μM of the active R-enantiomer of lacosamide (LCM), survival rate increases to 71%. Treatment with the inactive S-enantiomer (100 μM) has only a minor effect on survival rate.

FIG. 6. Radioactivity bound to the membrane fraction of CRMP-2-transfected Xenopus oocytes in absence (A) and presence (B) of excess of cold lacosamide (17 mM). (C) is specific binding, i.e. the difference between (A) and (B). Error bars are present, but too small to be prominent in this magnification.

EXAMPLE 1

Lacosamide, a New Analgesic and Anti-Epileptic Drug, Interacts with the Collapsin Response Mediator Protein, CRMP-2

The aim of the experiment was to identify proteins which interact with Lacosamide to resolve the molecular mechanism of action of Lacosamide in disease treatment.

Biological pull-down experiments (“Affinity Fishhook”) were performed by incubating a set of four Lacosamide-related affinity-reagents with biotinyl-moieties (R)—N-Benzyl-2-acetamido-6-[Nε-(biotinyl)-2-isothiocynato-6-aminohexanamido]-aminohexanamide((R)-7), (S)—N-Benzyl-2-acetamido-6-[Nε-(biotinyl)-2-isothiocynato-6-aminohexanamido]-aminohexanamide((S)-7), (R)—N-{3-[Nε-(biotinyl)-2-isothiocynato-6-aminohexanamide]-benzyl}-2-acetamido-3-methoxypropion-amide((R)-34) and (R)—N-{4-[Nε-(biotinyl)-2-isothiocynato-6-aminohexanamide]-benzyl}-2-acetamido-3-methoxypropion-amide((R)-35) to rat brain. Isolation of fractions led to enrichment of an overlapping set of proteins, including collapsing response mediator protein (CRMP-2) and some additional proteins related to the vesicle release machinery.

Several findings suggest that CRMP, in particular CRMP-2 is indeed a target of Lacosamide:

(a) The pattern of affinity captured proteins is completely different from raw extracts and controls and the protein is consistently captured under a variety of conditions.
(b) There appears to be some competition of affinity tags with the Lacosamide.
(c) Differences between active R- and less active S-enantiomers of Lacosamide can be found in 2D gels, their exact molecular nature however would require an in-depth mass spectrometry approach.

EXAMPLE 2

CRMP-2 Expression in Xenopus Oocytes: Binding Study with Lacosamide

The aim of this study was to confirm the interaction of Lacosamide with CRMP-2 in a classical competition protein binding experiment with [¹⁴C]-labeled lacosamide as radioligand.

Based on the results of the previous study, the present binding curve ranged from 1 to 100 μM (10 concentrations, in triplicates). With crude membranes from CRMP-2 transfected Xenopus oocytes and rat brain membranes, competitive and specific binding was observed. The KD-value appeared to be below 5 μM and could be competed by an excess of cold unlabeled lacosamide (17 mM, FIG. 6); B_max was about 200 pM/mg. Here the low specific radio activity of ¹⁴C-labelled Lacosamide potentially sets a limit to further binding experiments.

No specific binding was observed in the control oocyte membrane fraction and rat brain membrane fraction up to concentrations of 100 μM.

EXAMPLE 3

Influence of Lacosamide on Axon Growth in Hippocampal Primary Cells

It is known that CRMP-2 is critical for specifying axon/dendrite fate, possibly by promoting neurite elongation via microtubule assembly. Neurotrophins e.g. NT-3 and BDNF decrease phosphorylated CRMP-2, thereby promoting axonal outgrowth. Inactivation of CRMP-2, e.g. through phosphorylation by GSK-3β was shown to inhibit neurotropin-induced axonal outgrowth.

To show that the interaction of Lacosamide with CRMP-2 influences CRMP-2 activity, the effects of Lacosamide on the neurotrophin-induced neuronal differentiation were analyzed in vitro. It could be shown that the neurotrophins NT3 and BDNF stimulate axonal outgrowth in a primary culture of embryonal hippocampal neurons. Quantification of neurite outgrowth was performed by immunofluorescence microscopy employing an antibody against the axonal marker protein Tau-1. BDNF- and NT3-induced but not basal neuronal outgrowth was attenuated by Lacosamide (FIGS. 2 and 3). Lacosamide alone did not significantly change basal axonal outgrowth (FIG. 1). The findings indicate a functional interaction of Lacosamide and CRMP-2 antagonizing CRMP-2 activity.

EXAMPLE 4

Implications of CRMP-2 Silencing on the Neuroprotective Effects of Lacosamide in an In Vitro Assay

NMDA receptor-mediated excitotoxicity combined with calcium-imaging technologies have been employed as a cellular model of neurotoxicity In this functional assay, CRMP-2 has been shown to be postranslational modified after excitotoxic insult.

In order to analyze if the functional interaction of lacosamide with CRMP-2 has an influence on survival rates of neurons after excitotoxic insult, neural derivates of murine embryonal stem cells were exposed to excitotoxic insult (200 μM NMDA) and the survival rates were determined by Calcium imaging. It could be shown that the active R-enantiomer but not the inactive S-enantiomer of lacosamide increase neuronal survival rate from 16% to 71% and have thus clear neuroprotective properties (FIG. 5).

The neuroprotective effect of lacosamide could be diminished by pre-incubation with CRMP-2 siRNA, indicating that functional inactivation of CRMP-2 negatively influences the neuroprotective effects of lacosamide. These results suggest a functional interaction of lacosamide and CRMP-2.

Claims

1. A method for identifying a modulator of CRMP suitable for prevention, alleviation and/or treatment of a CRMP-associated disease, comprising wherein a substance interacting with CRMP is identified as a modulator of CRMP.

(a) selecting a substance,

(b) contacting the selected substance with CRMP, and

(c) determining whether CRMP interacts with the substance,

2. The method of claim 1, wherein CRMP comprises

(i) a polypeptide selected from the group consisting of SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ ID NO:10, SEQ ID NO:12 and fragments thereof, and/or

(ii) a polypeptide which is at least 70% identical to the polypeptide of (i).

3-5. (canceled)

6. The method of claim 1, wherein the CRMP is CRMP-2.

7. (canceled)

8. The method of claim 1, wherein the CRMP-associated disease is selected from neurological diseases, psychiatric diseases, inflammatory diseases, epilepsy, pain syndromes, motoneuron disorders, dyskinesias, tremor syndromes, psychoses, schizophrenia, arthritis and arthritic conditions.

9-14. (canceled)

15. The method of claim 1, wherein the CRMP-associated disease is a CRMP-2-associated disease.

16-20. (canceled)

21. The method of claim 1, wherein in step (b), the substance is contacted with a cell capable of expressing or overexpressing CRMP and/or with a non-human animal comprising a cell capable of expressing or overexpressing CRMP.

22-28. (canceled)

29. A cell capable of overexpressing or underexpressing CRMP and/or expressing a modified CRMP polypeptide.

30-31. (canceled)

32. A non-human animal comprising a cell capable of overexpressing or underexpressing CRMP and/or expressing a modified CRMP polypeptide.

33. (canceled)

34. A method for identifying a compound which is a disease-modifying compound and/or a compound suitable for neuroprotective treatment, comprising wherein a substance interacting with CRMP is identified as a disease-modifying compound and/or a compound suitable for neuroprotective treatment.

(a) selecting a substance,

(b) contacting the selected substance with CRMP, and

(c) determining whether CRMP interacts with the substance,

35. (canceled)

36. The method of claim 61, wherein the compound is lacosamide.

37. A complex comprising CRMP and a compound of Formula (I) wherein or a pharmaceutically acceptable salt or metabolite thereof; wherein, in the compound of Formula (I), electron-withdrawing and electron-donating groups are independently selected from halo, alkyl, alkenyl, alkynyl, nitro, carboxy, formyl, carboxyamido, aryl, guaternary ammonium, haloalkyl, aryl alkanoyl, hydroxy, alkoxy, carbalkoxy, amino, alkylamino, dialkylamino, aryloxy, mercapto, alkylthio, alkylmercapto and disulfide; and wherein the compound, or salt or metabolite thereof exhibits an affinity for CRMP characterized by a KD less than about 5 μM.

R is hydrogen, alkyl, alkenyl, alkynyl, aryl, aryl alkyl, heterocyclic, heterocyclic alkyl, alkyl heterocyclic, cycloalkyl or cycloalkyl alkyl, and R is unsubstituted or is substituted with at least one electron-withdrawing group and/or at least one electron-donating group;

R1 is hydrogen, alkyl, alkenyl, alkynyl, aryl alkyl, aryl, heterocyclic alkyl, alkyl heterocyclic, heterocyclic, cycloalkyl or cycloalkyl alkyl, and is unsubstituted or substituted with at least one electron-donating group and/or at least one electron-withdrawing group;

R2 and R3 are independently hydrogen, alkyl, alkenyl, alkynyl, alkoxy, alkoxyalkyl, aryl alkyl, aryl, halo, heterocyclic, heterocyclic alkyl, alkyl heterocyclic, cycloalkyl, cycloalkyl alkyl, or Z-Y, wherein R2 and R3 are each independently unsubstituted or substituted with at least one electron-withdrawing group and/or at least one electron-donating group;

Z is O, S, S(O)a, NR4, NR′6, PR4 or a chemical bond;

Y is hydrogen, alkyl, aryl, aryl alkyl, alkenyl, alkynyl, halo, heterocyclic, heterocyclic alkyl or alkyl heterocyclic, and is unsubstituted or substituted with at least one electron-donating group and/or at least one electron-withdrawing group, provided that when Y is halo, Z is a chemical bond, or

Z-Y taken together is NR4NR5R7, NR4OR5, ONR4R7, OPR4R5, PR4OR5, SNR4R7, NR4SR7, SPR4R5, PR4SR7, NR4PR5R6, PR4NR5R7, N+R5R6R7,

R′6 is hydrogen, alkyl, or alkenyl, and is unsubstituted or substituted with at least one electron-withdrawing group and/or at least one electron-donating group;

R4, R5 and R6 are independently hydrogen, alkyl, aryl, aryl alkyl, alkenyl or alkynyl, and are each independently unsubstituted or substituted with at least one electron-withdrawing group and/or at least one electron-donating group;

R7 is R6, COOR8, or COR8, and is unsubstituted or substituted with at least one electron-withdrawing group and/or at least one electron-donating group;

R8 is hydrogen, alkyl or aryl alkyl, and is unsubstituted or substituted with at least one electron-withdrawing group and/or at least one electron-donating group;

n is 1-4; and

a is 1-3;

38-41. (canceled)

42. The complex of claim 37, wherein CRMP is CRMP-2 and/or the compound of Formula (I) is lacosamide.

43-44. (canceled)

45. The cell of claim 29, comprising a complex that comprises CRMP and a compound of Formula (I) or a pharmaceutically acceptable salt or metabolite thereof having an affinity for CRMP characterized by a KD less than about 5 μM.

46. The non-human animal of claim 32, wherein said cell comprises a complex comprising CRMP and a compound of Formula (I) or a pharmaceutically acceptable salt or metabolite thereof having an affinity for CRMP characterized by a KD less than about 5 μM.

47. A method for preparing a complex of any of claim 37, comprising contacting CRMP with a compound of Formula (I) or a pharmaceutically acceptable salt or metabolite thereof having an affinity for CRMP characterized by a KD less than about 5 μM.

48-52. (canceled)

53. A diagnostic method for a CRMP-associated disease, comprising: wherein detection of said complex is indicative of CRMP mediation of the disease and of utility of the compound or salt or metabolite thereof in treatment of the disease.

(a) contacting a biological sample from a subject with a compound of Formula (I) or a pharmaceutically acceptable salt or metabolite thereof having an affinity for CRMP characterized by a KD less than about 5 μM, and thereafter

(b) assaying the biological sample for a complex comprising CRMP and the compound or salt or metabolite thereof,

54-60. (canceled)

61. A method for modifying disease and/or for neuroprotection in a subject, comprising administering a compound of Formula (I) or a pharmaceutically acceptable salt or metabolite thereof to the subject.