WO2024211310A1 - Methods of dosing spinogenic compounds - Google Patents

Abstract

Provided herein is a method for generating functional spines on a neuron which method comprises transiently contacting said neuron with an effective amount of a spinogenic compound wherein said transient contact initiates spinogenic activity that leads to formation of new functional spines; and wherein said transient contact of an effective amount terminates after initiation and before for maturation of said functional spines.

Description

METHODS OF DOSING SPINOGENIC COMPOUNDS

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit under 35 U.S.C. 119(e) of United States Provisional Application Serial No. 63/456,685, filed April 3, 2023, which is hereby incorporated by reference in its entirety.

FIELD

[0002] Provided herein are methods and dosages for initiating spinogenesis in a subject in need thereof.

BACKGROUND

[0003] Human neurodegenerative diseases are most commonly associated with age. Many of these diseases arise from the reduced capacity of aged or diseased neurons to generate functional neural spines and synapses in sufficient amounts necessary for neurons to communicate with each other. The underlying marker for many of these neurodegenerative diseases is the loss of an adequate density of functional dendritic spines. The resulting pathology leads to one or more functional decline(s) in memory, mobility, and other critically human characteristics.

[0004] Current treatments for most or all human neurodegenerative diseases act primarily to delay further functional decline in the patient. That is to say that these treatments slow the progression of the disease or the symptoms associated therewith without significantly restoring any previously loss functionality.

[0005] Still further, these treatments require substantially continuous maintenance of a therapeutic concentration of the drug in the brain in order to be most effective. For example, acetylcholine is a neurotransmitter that, in addition to other functions, plays a role in muscle movement, short-term memory and learning. Neurodegenerative diseases involving loss of one or more of these functional attributes are often treated with cholinesterase inhibitors. Such inhibitors reduce the breakdown of acetylcholine in the brain and require a substantially continuous presence of an effective amount of the inhibitor. Nevertheless, the disease pathology continues unabated. .

[0006] Many elderly patients afflicted with and treated for a neurodegenerative disease are also afflicted with one or more additional conditions or diseases that require drug therapy. This imposes a further constraint on the attending clinician to limit the choice of drugs used so as to avoid adverse drugdrug interactions.

[0007] Given the increased incidence of neurodegenerative diseases due at least in part to an aging population, there is a need for methods for treating such diseases. Ideally, such methods would impart restorative properties and would minimize adverse drug-drug interactions and reduce the severity of or eliminate side-effects. Such methods would represent a paradigm shift in the treatment of these diseases. SUMMARY

[0008] Disclosed herein are methods for treating a subject afflicted with a neurodegenerative disease or condition that would benefit from spinogenesis. The disease or condition may be characterized by a loss of spine density in diseased neurons. In turn, this leads to loss or decreased effectiveness of one or more functional properties in the subject.

[0009] The methods described herein initiate spinogcnic activity in mammalian neurons in a very short time (e.g., within an hour of administration). Formation of functional dendritic spines that can form functional synapses with axons from other neurons occurs over a longer time period of several hours or more (e.g., about 4 hours). The resulting synapses restore functional communication between these neurons leading to repair of some or more of the normal functional properties controlled by the neurons.

[0010] The compounds used in the methods described below have a very short half-life in mice of about 30 minutes or less and, in one case, the half-life is 24 minutes. Moreover, the concentration of these compounds in the brain tissue and serum is very low and is on the order of nanomoles. Such properties evidence a transient presence in the brain prior to elimination from the body. For example, in mice approximately 96% of the drug has been eliminated from the body within the first 2 hours after administration. Without being limited to any theory, we postulate that the compounds used in the methods herein merely initiate or signal for the initiation of spinogenesis leaving the neuron to independently further the process through maturation.

[0011] In one embodiment, there are provided methods for increasing spine density in aged or diseased neurons by initiating spinogenesis through transient contact with a compound or a composition comprising such a compound described herein with such neurons. Such transient contact initiates repair of neural communications by increasing the number of functional dendritic spines (spines that form synapses) on the neurons. Our in vivo studies using only a single daily dose of the compound for 4 days nevertheless evidenced significant differences between treated diseased mice and untreated diseased mice. Such is both surprising and unexpected since the in vivo concentration of the administered compound decreases by approximately 96% within the first 2 hours, and is effective at nanomolar levels.

[0012] Again, without being limited to any theory, the compounds described herein stimulate both spinogenesis and the formation of dendritic spines capable of forming functional synapses with axons from other neurons following transient contact (an “instructive cue”) with a substantial portion of the biological transformations occurring after more than 96% of the compound is no longer present.

[0013] This combination of a short half-life coupled with biological transformations continuing after eliminations of most of the compound is contemplated to allow for reduced drug side effects and/or prevent possible drug-drug interactions in subjects who are currently medicated with one or more additional pharmaceutical agents.

[0014] Without being limited to any theory, the data suggests that the compounds described herein initiate spinogenic activity in neurons resulting in the formation of spines capable of generating functional synapses. While the half-life of these compounds is quite short in a mammal, they are still capable of initiating and maturating spinogenesis well after several half-life periods have expired. This suggests that these compounds activate or turn-on spinogenic activity including maturation which has been reduced or lost due a neurological condition. The fact that such spinogenic activity including maturation occurs well after the compound’s in vivo concentration approaches zero suggests that just initiating spinogenic activity is all that is required. Based on the above, it is possible that the neurological condition underlying the loss of spine density in the affected neuron is due primarily to the condition’s compromising the activation of spinogenic activity. If so, the ability of the compounds described herein to activate spinogenic activity addresses a key component of disease progression - loss of spine density in the affected neurons leading to loss of functionality (e.g., loss of short-term memory, loss of muscle functionality, etc.).

[0015] Regardless, the data herein demonstrates that the compounds described herein initiate spinogenic activity. Moreover, this activity leads to spine maturation and synapse formation with an adjacent axon despite the rapid in vivo clearance of the activating compound. In combination, this data provides significant insight into the pathology of such neurological conditions as well as methods and dosing amounts that offset the loss of spine density associated with that condition. As such, the methods described herein provide treatment protocols wherein a unit dose of the compound is administered once or perhaps twice a day to achieve spinogenic activity coupled with synapse formation.

[0016] Given that only limited amounts of the compound arc required to initiate and generate functional spinogenic activity, leading to functional synapses, the methods and unit doses described herein significantly target the amount of compound that is required to effect spinogenesis and limited dosing of the mammal to just once or twice per day notwithstanding the rapid in vivo clearance of the compound from the mammal. Stated differently, imitation of the spinogenetic activity is believe to be solely required to effect the desired formation of functional synapse.

[0017] In one embodiment, there is provided a method for generating functional spines on a neuron which method comprises transiently contacting said neuron with an effective amount of a compound of formula I:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, wherein R is hydrogen, C1-C4 alkyl, halo, hydroxyl, amino, cyano or nitro; q is from 2 to 8; and wherein said transient contact initiates spinogenic activity that leads to formation of new functional spines; and wherein said transient contact of an effective amount terminates after initiation and before complete maturation of said functional spines.

0018] In one embodiment, the effective amount of a compound of formula I provides for a maximum concentration of the compound, or a salt, stereoisomer, mixture of stereoisomers, or metabolite thereof, of no more than about 30 nM in a brain tissue.

[0019] In one embodiment, the compound is

or a pharmaceutically acceptable salt thereof.

[0020] In one embodiment, there is a provided a method for repairing diseased neurons in a mammal afflicted with a neurodegenerative disease which method comprises: administering to said mammal a single daily dose of an effective amount of a compound of formula I:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, wherein R is hydrogen, C1-C4 alkyl, halo, hydroxyl, amino, cyano or nitro; q is from 2 to 8; and wherein said compound contacts said neurons and initiates their repair by the subsequent formation of new dendritic spines which spines form functional synapses with axons on other neurons wherein said repair is continued in the absence of the effective amount of said compound; wherein said neurodegenerative disease is characterized as early-stage or mid-stage .

[0021] In one embodiment, the effective amount of the compound of formula I provides for a concentration of up to 30 nM in a brain tissue.

[0022] In one embodiment, the compound of formula I is

or a pharmaceutically acceptable salt thereof , where R is hydrogen and q is 4 or 6, the mammal is a human, and said effective amount is about 0.1 to 0.4 mg/kg and preferably from about 0.1 to 0.4 mg/kg/day.

[0023] In one embodiment, the mammal is human and the compound of formula I is administered at a dose of about 0.25 mg/kg and preferably at a dose of about 0.25 mg/kg/day.

[0024] In one embodiment, the neuronal disease or disorder is a neurodegenerative disease. In one embodiment, the neurodegenerative disease is selected from Alzheimer’ s disease (AD), amyotrophic lateral sclerosis (ALS), Parkinson’s disease, frontotemporal dementia, and Huntington’s disease.

[0025] In one embodiment, the neurodegenerative disease is Alzheimer’ s disease.

[0026] In one embodiment, the neurodegenerative disease is art recognized to be early stage or midstage but not late stage as those terms are recognized in the art.

[0027] In one embodiment, the dose administered is therapeutically effective in treating the neuronal disease or disorder.

[0028] In one embodiment, there is a provided a method for repairing aged or diseased neurons in a mammal in need thereof by initiating formation of dendritic spines according to a method provided herein. [0029] In one embodiment, is provided a unit dose for initiating formation of stable, functional synapses in a mammal suffering from decreased spine density and accordingly compromised functional synapses, said unit dose comprising no more than about 0.4 mg/kg/day of a compound of formula IA:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, q is from 2 to 8; and wherein said compound has a serum half life of less than 3 hours, and further wherein said unit dose provides for formation of stable functional synapses in said mammal.

[0030] In one embodiment, provided is a method for generating functional spines on a neuron which method comprises transiently contacting said neuron with an effective amount of a compound of formula I:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, wherein R is hydrogen, C1-C4 alkyl, halo, hydroxyl, amino, cyano or nitro; q is from 2 to 8; and wherein said transient contact initiates spinogenic activity that leads to formation of new functional spines; and wherein said transient contact of an effective amount terminates after initiation and before complete maturation of said functional spines.

[0031] In one embodiment, provided is a method to initiate spinogenic activity in a mammal suffering from a neurological condition characterized by diseased neurons with compromised spinogenic activity characterized by a decreased ability to initiate spinogenic activity that leads to formation of new functional spines, said method comprises contacting said neuron with an effective amount of a compound of formula I:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, wherein R is hydrogen, C1-C4 alkyl, halo, hydroxyl, amino, cyano or nitro; q is from 2 to 8; and wherein said transient contact initiates spinogenic activity that leads to formation of new functional spines; and wherein said transient contact of an effective amount terminates after initiation and before complete maturation of said functional spines.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] FIG. 1 shows escape latency (seconds, y-axis) vs. time in days (x-axis) in an embodiment according to Example 1.

[0033] FIGs. 2A, 2B, 2C, and 2D show frequency, duration in zone (seconds), distance moved (cm), and velocity (cm/s) (y-axis), respectively, for wild type (WT) and 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1.

[0034] FIG. 3 shows inactive cumulative duration (s) for WT and 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1.

[0035] FIG. 4 shows PSD95 (panels Al a- Aid), colocalization (panels A2a-A2d), SYN (panels A3a- A3d) for WT and 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1.

[0036] FIG. 5A, FIG. 5B, and FIG 5C show number of spots for PSD95 (FIG. 5A), SYN (FIG. 5B), and co-localized PSD95/SYN (FIG. 5C) for WT and 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1; Lane A - WT vehicle; B - 3xTg-AD vehicle; C - 3xTg-AD Compound 1, 3 mg/kg; D - 3xTg-AD Compound 1, 30 mg/kg.

[0037] FIG. 6 shows images of dendritic spines in an embodiment according to Example 1.

[0038] FIG. 7 is a chart showing number of total, mushroom, stubby and thin spines per 100 pm for WT and 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1. [0039] FIG. 8 is a chart showing number of spines per 20 pm for WT and 3xTg-AD mice untreated (control) and treated with vehicle and treated with Compound 1 at 0.1, 0.3, 1, 3, and 10 pM, in an embodiment according to Example 1.

[0040] FIG. 9 is a depiction of various gel bands for WT and 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1. Lane A - WT vehicle; B - 3xTg-AD vehicle; C - 3xTg-AD Compound 1, 3 mg/kg; D - 3xTg-AD Compound 1, 30 mg/kg; E - WT vehicle; F - 3xTg-AD vehicle; G- 3xTg-AD Compound 1, 3 mg/kg; H - 3xTg-AD Compound 1, 30 mg/kg.

[0041] FIG. 10 is a depiction of levels of various proteins of interest in Alzheimer’s disease for WT and 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1.

[0042] FIG. 11 depicts immunohistochemistry for certain proteins in 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1.

[0043] FIG. 12A and FIG. 12B are bar charts depicting levels of amyloid beta, tau, and phosphorylated tau for 3xTg-AD mice treated with vehicle and treated with Compound 1 at 3 and 30 mg/kg, in an embodiment according to Example 1.

[0044] FIG. 13A shows selected neurite segments, of at least 20 pm, the width is around 0.3 pm, and the border is around 2 pm around the segments to provide a total of about 4-5 pm diameter for locating pre- and post-synaptic structures in an embodiment. FIG. 13B is a cartoon depicting the anatomy of a neural junction and indicating the location of the pre- and post-synaptic structures.

[0045] FIG. 14 shows a bar chart indicating DIV 14 rat hippocampal neurons treated with a compound described herein for 4 hours in an embodiment according to Example 1. The Y-axis is dendritic spines per 20 pm and the x-axcs arc concentration of test compound in pM. First group: co-localized synaptobrevin/PSD95; second group: synaptobrevin only; third group: PSD95 only.

[0046] FIG. 15 shows a graph of Gait Scores in Compound 1 and Vehicle Treated TDP-43 Mice with daily treatment beginning on day 14 in an embodiment according to Example 2.

[0047] FIG. 16 shows a graph of Kyphosis Scores in Compound 1 and Vehicle Treated TDP-43 Mice with daily treatment beginning on day 14 in an embodiment according to Example 2.

[0048] FIG. 17 shows a graph of Tremor Scores in Compound 1 and Vehicle Treated TDP-43 Mice with daily treatment beginning on day 14 in an embodiment according to Example 2.

[0049] FIG. 18 shows a graph of Survival of TDP-43 ALS Mice treated with Compound 1 in an embodiment according to Example 2.

[0050] FIG. 19 shows the Layer 5 Motor Cortex basal and apical spine density of WT and Ubqln2 mice treated with vehicle, and Compound 1 (10 mg/kg). [0051] FIG. 20 shows images of Layer 5 Motor Cortex dendritic spines.

[0052] FIG. 21 shows the Medial Prefrontal Cortex basal and apical spine density of WT and Ubqln2 mice treated with vehicle, and Compound 1 (10 mg/kg).

[0053] FIG. 22 shows images of Medial Prefrontal Cortex dendritic spines.

[0054] FIG. 23 shows the Field CAI Hippocampus basal and apical spine density of WT and Ubqln2 mice treated with vehicle, and Compound 1 (10 mg/kg).

[0055] FIG. 24 shows images of Field CAI Hippocampus dendritic spines.

DETAILED DESCRIPTION

[0056] Generally the compounds and methods described herein provide for the administration of spinogenesis-initiating concentrations of compounds that are useful in the treatment, prevention, or reversal of neuronal diseases or disorders. In some embodiments, the compositions and methods provide a spinogenesis-initiating concentration that is useful for treating a neuronal disease or disorder, where the concentration that is sufficiently small to reduce drug-drug interactions, minimize side effects, and expand suitable patient populations.

Definitions

[0057] The following description sets forth exemplary embodiments of the present technology. It should be recognized, however, that such description is not intended as a limitation on the scope of the present disclosure but is instead provided as a description of exemplary embodiments.

[0058] As used in the present specification, the following words, phrases and symbols are generally- intended to have the meanings as set forth below, except to the extent that the context in which they are used indicates otherwise.

[0059] The term “spinogenesis” and the like refer, in the usual and customary sense, to formation (e.g., initiation, growth and/or maturation) of dendritic spines on neurons. In some embodiments, spinogenesis comprises an increase in spine density. In some embodiments, the compounds provided herein promote spinogenesis without affecting the normal distribution of spine morphologies. In further embodiments, the spinogenesis may result in a change in the distribution of spine morphologies. The promotion is relative to a control without administration of the compound.

[0060] As used herein, the term “dendrite” refers to the branched extension of a neuron cell. Dendrites are typically responsible for receiving electrochemical signals transmitted from the axon of an adjacent neuron. The terms “dendritic spines”, “dendrite spines”, or "spines" refer to protoplasmic protuberances on a neuron cell (e.g., on a dendrite). In some embodiments, dendritic spines may be described as having a membranous neck which may be terminated with a capitulum (e.g., head). Dendritic spines are classified according to their shape, for example, as headless, thin, stubby, mushroom, or branched. Dendritic spine density refers to the total number of dendritic spines per unit length of a neuron cell. For example, the dendritic spine density may be given as the number of dendritic spines per micron, or per 20 microns.

[0061] The term “dendritic spine initiation” and the like refer, in the usual and customary sense to processes which lead to an increased number of dendritic spines or increased development of dendritic spines. The term “dendritic spine morphology” and the like refer, in the usual and customary sense, to physical characterization of a dendritic spine (e.g., shape and structure). Improvement of dendritic spine morphology is a change in morphology (e.g., increase in length or increase in width) that results in increased functionality (e.g., increased area of contact between neurons). As known in the art and disclosed herein, exemplary methods for such characterization include measurement of the dimensions (i.c., length and width) of dendritic spines. Accordingly, the term “improving dendritic spine morphology” generally refers to an increase in length, width, or both length and width of a dendritic spine.

[0062] “Binding” refers to at least two distinct species (e.g. chemical compounds including biomolecules, or cells) becoming sufficiently proximal to react or interact thereby resulting in the formation of a complex. For example, the binding of two distinct species (e.g., a protein and a compound described herein) may result in the formation of a complex wherein the species are interacting via non- covalent or covalent bonds. In some embodiments, the resulting complex is formed when two distinct species (e.g., a protein and a compound described herein) interact via non-covalent bonds (e.g., electrostatic, van der Waals, or hydrophobic).

[0063] As defined herein, the term “activation,” “activate,” “activating” and the like in reference to a protein-activator (e.g. agonist) interaction means positively affecting (e.g. increasing) the activity or function of the protein relative to the activity or function of the protein in the absence of the activator (e.g. compound described herein).

[0064] As defined herein, the terms “inhibition,” “inhibit,” “inhibiting” and the like, are to be given their customary meanings to those of skill in the art. In reference to a protein-inhibitor (e.g. antagonist) interaction, the terms “inhibition,” “inhibit,” and “inhibiting” mean negatively affecting (e.g. decreasing) the functional activity of the protein relative to the functional activity of the protein in the absence of the inhibitor (e.g. compound described herein).

[0065] Reference to “about” a value or parameter herein includes (and describes) embodiments that are directed to that value or parameter per se. In certain embodiments, the term “about” includes the indicated amount + 10%. In other embodiments, the term “about” includes the indicated amount ± 5%. In certain other embodiments, the term “about” includes the indicated amount + 1%. Also, to the term “about X” includes description of “X”. Also, the singular forms “a” and “the” include plural references unless the context clearly dictates otherwise. Thus, e.g., reference to "the compound" includes a plurality of such compounds and reference to “the assay” includes reference to one or more assays and equivalents thereof known to those skilled in the art.

[0066] ‘ 'Halogen” or “halo” includes fluoro, chloro, bromo, and iodo.

[0067] The terms “optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances in which it does not. Also, the term “optionally substituted” refers to any one or more hydrogen atoms on the designated atom or group may or may not be replaced by a moiety other than hydrogen. The term “optionally substituted” with reference to a group is intended to be construed as describing the unsubstituted group and the group substituted by the indicated or defined substituent(s).

[0068] Some compounds exist as tautomers. For example, amide containing compounds may exist in equilibrium with imidic acid tautomers. Regardless of which tautomer is shown, and regardless of the nature of the equilibrium among tautomers, the compounds are understood by one of ordinary skill in the art to comprise all tautomers.

[0069] Any formula or structure given herein is also intended to represent isotopically labeled forms of the compounds as well as unlabeled forms. Isotopically labeled compounds have structures depicted by the formulas given herein except that one or more atoms are replaced by an isotope having the indicated atomic mass or mass number. Examples of isotopes that can be incorporated into compounds of the disclosure, or counter-ions thereto, include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine and chlorine, such as, but not limited to ²H (deuterium, D), ³H (tritium), ^HC, ¹³C, ¹⁴C, ¹⁵N, ¹⁸F, ³¹ P, ³²P, ³⁵S, ³⁶C1 and ¹²⁵I. Various isotopically labeled compounds are possible under the present disclosure, for example those into which radioactive isotopes such as ³H and ¹⁴C are incorporated. Such isotopically labelled compounds may be useful in metabolic studies, reaction kinetic studies, detection or imaging techniques, such as positron emission tomography (PET) or single-photon emission computed tomography (SPECT) including drug or substrate tissue distribution assays or in radioactive treatment of patients.

[0070] The disclosure also includes “deuterated analogs” of compounds, and counter-ions thereto, in which from 1 to n hydrogen atoms is/are replaced by deuterium, in which n is the number of hydrogens in the molecule. Such compounds are synthesized by means well known in the art, for example by employing starting materials in which one or more hydrogens have been replaced by deuterium. [0071] Isotopically labeled compounds of this disclosure and prodrugs thereof can generally be prepared by carrying out the procedures disclosed in the schemes or in the examples and preparations described below by substituting a readily available isotopically labeled reagent for a non-isotopically labeled reagent.

[0072] The concentration of such a heavier isotope, specifically deuterium, may be defined by an isotopic enrichment factor. Tn the compounds of this disclosure any atom not specifically designated as a particular isotope is meant to represent any stable isotope of that atom. Unless otherwise stated, when a position is designated specifically as “H” or “hydrogen,” the position is understood to have hydrogen at its natural abundance isotopic composition. Accordingly, in the compounds of this disclosure any atom specifically designated as a deuterium (D) is meant to represent enrichment of deuterium above a naturally occurring level at the indicated position.

[0073] Compounds described herein may be present as a salt, such as a pharmaceutically acceptable salt. Compounds are capable of forming salts such as acid and/or base salts. Provided are also pharmaceutically acceptable salts, hydrates, solvates, tautomeric forms, polymorphs, and prodrugs of the compounds described herein. “Pharmaceutically acceptable” or “physiologically acceptable” refer to compounds, salts, compositions, dosage forms and other materials which are useful in preparing a pharmaceutical composition that is suitable for veterinary or human pharmaceutical use. Salts of compounds described herein can be prepared according to procedures described herein and as known in the art.

[0074] The term “pharmaceutically acceptable salt” of a given compound, refers to salts that retain the biological effectiveness and properties of the given compound, and which are not biologically or otherwise undesirable. “Pharmaceutically acceptable salts” or “physiologically acceptable salts” include, for example, salts with inorganic acids and salts with an organic acid. In addition, if the compounds described herein are obtained as an acid addition salt, the free base can be obtained by basifying a solution of the acid salt. Conversely, if the product is a free base, an addition salt, particularly a pharmaceutically acceptable addition salt, may be produced by dissolving the free base in a suitable solvent and treating the solution with an acid, in accordance with conventional procedures for preparing acid addition salts from base compounds. Those skilled in the art will recognize various synthetic methodologies that may be used to prepare nontoxic pharmaceutically acceptable addition salts. Pharmaceutically acceptable acid addition salts may be prepared from inorganic and organic acids. Salts derived from inorganic acids include hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, and the like. Salts derived from organic acids include acetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid, malic acid, malonic acid, succinic acid, maleic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, methanesulfonic acid, ethanesulfonic acid, p-toluene-sulfonic acid, salicylic acid, isobutyric acid, suberic acid, lactic acid, and the like. Likewise, pharmaceutically acceptable base addition salts can be prepared from inorganic and organic bases. Salts derived from inorganic bases include, by way of example only, sodium, potassium, lithium, ammonium, calcium and magnesium salts. Salts derived from organic bases include, but are not limited to, salts of primary, secondary and tertiary amines, such as alkyl amines (i.e., NH2(alkyl)), dialkyl amines (i.e., HN(alkyl)2), trialkyl amines (i.e., N(alkyl)3), substituted alkyl amines (i.e., NH2(substituted alkyl)), di(substituted alkyl) amines (i.e., HN(substituted alkylh), tri(substituted alkyl) amines (i.e., N(substituted alkylh), alkenyl amines (i.e., NH2(alkenyl)), dialkenyl amines (i.e., HNialkenyl ), trialkenyl amines (i.e., N(alkenyl)s), substituted alkenyl amines (i.e., NfLi'substituted alkenyl)), di(substituted alkenyl) amines (i.e., HN(substituted alkenyl h). tri(substituted alkenyl) amines (i.e., N(substituted alkenyl^, mono-, di- or tri- cycloalkyl amines (i.e., NHi(cycloalkyl). HN(cycloalkyl)2, Nicycloalkyl),), mono-, di- or triarylamines (i.e., NH2(aryl), HN(aryl)z, Nfarylh), or mixed amines, etc. Specific examples of suitable amines include, by way of example only, isopropylamine, trimethyl amine, diethyl amine, tri(iso-propyl) amine, tri(n-propyl) amine, ethanolamine, 2-dimethylaminoethanol, piperazine, piperidine, morpholine, N-ethylpiperidine, and the like. Methods of preparing a salt also include mixing a compound by redox reaction with an active metal, or by exchange of ions, for example, due to differing solubility of salts.

[0075] A “solvate” is a solid form of a compound in which solvent molecules are incorporated. A solvate is formed by the interaction of a solvent and a compound. A hydrate is a solvate in which the solvent is water. Solvates of salts of compounds described herein are also provided.

[0076] As used herein, “pharmaceutically acceptable carrier” or “pharmaceutically acceptable excipient” includes any and all solvents, dispersion media, fillers, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents and the like. The use of such media and agents for pharmaceutically active substances is well known in the art. Except insofar as any conventional media or agent is incompatible with the active ingredient, its use in the therapeutic compositions is contemplated. Supplementary active ingredients can also be incorporated into the compositions.

[0077] ‘ ‘Treatment” or “treating” provides a beneficial or desired result, e.g., an improvement in one or more clinical indicia of a disease or disorder. Beneficial or desired results may include one or more of the following: decreasing or ameliorating one or more symptoms of the disorder, diminishing the extent of the disorder; (e.g., stabilizing the disorder, preventing or delaying the worsening or progression of the disorder); providing partial or total remission of the disorder; enhancing effect of another medication; increasing the quality of life; and/or prolonging survival in a population of patients.

[0078] “ Prevention” or “preventing” means blocking development of a disease or disorder, or symptoms thereof. Compounds may, in some embodiments, be administered to a subject (including a human) who is at risk of, for example, has a family history, of the disease or disorder. Prevention may comprise delay in reaching predefined disease milestones or reduction in appearance or progression of an index of the disease or disorder. [0079] A “dose” refers to a single discrete administration. A “dose cycle” refers to two or more doses, where the doses are separated by a period of time.

[0080] “Subject” refers to an animal, such as a mammal, e.g. a human that may benefit from administration of a compound described herein. The methods described herein may be useful in human therapy and/or veterinary applications. In some embodiments, the subject is a mammal. In some embodiments, the subject is a human. When the subject is a human person, the subject may be referred to as a “patient.”

[0081] The term “therapeutically effective amount” of a compound described herein means an amount sufficient to effect treatment of a disease or disorder described herein when administered to a subject. The therapeutically effective amount may vary depending on the subject, the disease or disorder being treated, the weight and age of the subject, the severity of the disease or disorder, any complications of the disease or disorder that have developed, and the manner of administering, and generally can be determined by a medical practitioner.

[0082] The term “refractory” means that a subject having a disease or disorder has previously been resistant to treatment of the disease or disorder. For example, one or more symptoms of the disease or disorder persisted following treatment.

[0083] The term “marker” means a characteristic of a subject that indicates a risk for developing a disease or disorder. For example, a marker may be a genetic indicator associated with a disease or disorder; a marker may be a personal history of the disease or disorder; a marker may be a family history, e.g., a genetic relative or relatives having had the disease or disorder or a related disease or disorder; or a marker may be a test result or a symptom.

[0084] The term "transient" as it relates to drug presence in vivo means that an effective amount of the drug is present only for a short period of time whereas the biological processes leading to the biologically end point (in this case, functional dendritic spines) continue well after the drug is below its effective amount or is its absence (less than 5% of the effective amount of the drug remains in the serum). For a drug with a 24-minute half-life, the drug is considered absent after in less than about 2 hours after administration. A person of skill in the art will appreciate that the half-life of a compound in one mammal may differ from another mammal. Accordingly, the half-life of a compound described herein, when administered to a human, may differ from the values described, which were measured in rodents.

[0085] The term “repair” refers to the generation of new functional synapses.

[0086] The term “functional” refers to the ability of a spine or synapse to communicate between neurons. [0087] The term “neurodegenerative disease” refers to one of a subset of neuronal diseases or disorders that are incurable. These diseases are debilitating and result in progressive degeneration and / or death of nerve cells and ultimately death of the subject. These diseases are categorized into at least the following two components: those that affect movement (called ataxias), or mental functioning (called dementias). Such neurodegenerative diseases include but are not limited to dementia (including by way of example only, Alzheimer’s disease (AD) and frontotemporal dementia), amyotrophic lateral sclerosis (ALS), Parkinson’s disease, and Huntington’s disease. Examples of neuronal diseases that are not neurodegenerative include fragile X syndrome, autism, chronic stress, and attention-deficit/hyperactivity disorder (ADHD).

[0088] The terms “early stage”, "mid-stage", and "late stage" for each neurodegenerative disease are well known and many have defined terms known to an attending clinician. For Alzheimer's Disease (AD), these stages are defined in https://www.alz.org/alzheimers-dementia/stages which is incorporated herein by reference in its entirety. Thus, an early stage AD patient may exhibit memory lapses including: coming with the right word or name; remembering names when introduced to new people; having difficulty performing tasks in social or work settings; forgetting material that was just read; losing or misplacing a valuable object; experiencing increased trouble with planning or organizing. A mid-stage AD patient may exhibit difficulty expressing thoughts and performing routine tasks without assistance, including: Being forgetful of events or personal history; Feeling moody or withdrawn, especially in socially or mentally challenging situations; Being unable to recall information about themselves like their address or telephone number, and the high school or college they attended; Experiencing confusion about where they are or what day it is; Requiring help choosing proper clothing for the season or the occasion; Having trouble controlling their bladder and bowels; Experiencing changes in sleep patterns, such as sleeping during the day and becoming restless at night; Showing an increased tendency to wander and become lost. A late stage AD patient may exhibit lack of ability to respond to their environment and require assistance and personal care, including: Lose awareness of recent experiences as well as of their surroundings; Experience changes in physical abilities, including walking, sitting and, eventually, swallowing; Have difficulty communicating; Become vulnerable to infections, especially pneumonia.

[0089] For ALS, these stages are defined in https://alsnewstoday.com/stages-of-als/ and https://www.mda.org/disease/amyotrophic-lateral-sclerosis/signs-and-symptoms/stages-of-als each which is incorporated herein by reference in its entirety. Thus, an early stage ALS patient may exhibit symptoms including: Muscles may be weak and soft, or they may be stiff, tight, and spastic; Muscle cramping and twitching (fasciculation) occurs, as does loss of muscle bulk (atrophy); Symptoms may be limited to a single body region or mild symptoms may affect more than one region; The person may experience fatigue, poor balance, slurred words, a weak grip, tripping when walking, or other minor symptoms. A mid-stage ALS patient may exhibit: paralysis of some muscles, while others are weakened or unaffected; Fasciculations may continue; Unused muscles may cause contractures, in which the joints become rigid, painful, and sometimes deformed; If a fall occurs, the person may not be able to stand back up alone; Weakness in swallowing muscles may cause choking and greater difficulty eating and managing saliva; Weakness in breathing muscles can cause respiratory insufficiency, especially when lying down; Some people experience bouts of uncontrolled and inappropriate laughing or crying (pseudobulbar affect). A late stage ALS patient may exhibit: Most voluntary muscles are paralyzed; the diaphragm muscles are severely compromised; mobility is extremely limited, and help is needed in caring for most personal needs; Poor respiration may cause fatigue, fuzzy thinking, headaches, and susceptibility to pneumonia; Speech, or eating and drinking by mouth, may not be possible.

[0090] For Parkinson’s Disease (PD), there are 5 separate components of this disease set forth in https://www.parkinson.org/Understanding-ParkinsonsAVhat-is-Parkinsons/Stages-of-Parkinsons which is incorporated herein by reference in its entirety. These stages are further categorized as early stages (components 1 and 2 of the 5 components), mid-stages (components 2 and 3 of the 5 components) and latc-stagc (components 4 and 5 of the 5 components). Other ncurodcgcncrativc diseases likewise have well defined stages of the disease. Stage 1 : During this initial stage, the person has mild symptoms that generally do not interfere with daily activities; Tremor and other movement symptoms occur on one side of the body only; Changes in posture, walking and facial expressions occur. Stage 2: symptoms start getting worse; Tremor, rigidity and other movement symptoms affect both sides of the body; Walking problems and poor posture may be apparent; The person is still able to live alone, but daily tasks are more difficult and lengthy. Stage 3: Considered mid-stage, loss of balance and slowness of movements are hallmarks; Falls are more common; The person is still fully independent, but symptoms significantly impair activities such as dressing and eating. Stage 4: Symptoms are severe and limiting; It’s possible to stand without assistance, but movement may require a walker; The person needs help with activities of daily living and is unable to live alone. Stage 5: Symptoms are debilitating; Stiffness in the legs may make it impossible to stand or walk; The person requires a wheelchair or is bedridden; Around-the-clock nursing care is required for all activities; The person may experience hallucinations and delusions.

[0091] For Huntington’s disease (HD) stages are described at https://hopes.stanford.edu/stages-of- huntingtons-disease/, the content of which is incorporated herein by reference in its entirety. Early stage symptoms include motor symptoms in the extremities, including involuntary twitches in the fingers, toes, and face, minor loss of coordination, and may have trouble performing complicated motions; cognitive symptoms include difficulty thinking through complicated tasks; behavioral symptoms include depression, irritability, disinhibition. Mid-stage Huntington’s disease symptoms may lead to difficulty working or driving, and unable to perform household chores; motor symptoms include chorea, difficulty with voluntary motor tasks such as walking, problems with balance, and difficulty swallowing; cognitive symptoms include trouble organizing information and thinking clearly, and inability to solve problems; behavioral symptoms include increasing severity of those for early stage, and additionally include apathy and decreased sexual desire. Late stage symptoms lead to difficulty in all aspects of life, including speech, and patients may remain bedridden; motor symptoms include severe difficulty with voluntary movement, rigidity, dystonia, and bradykinesia; cognitive symptoms are debilitating; and behavioral symptoms include apathy (possibly sufficient to counteract depression) and psychosis.

Treatment Methods and Uses

[0092] Described herein are methods for the prevention, repair, and/or treatment of a neuronal disease or disorder by administering to a subject a sufficient amount of a compound so as to provide for a concentration in the brain that promotes spinogenesis in one or more neurons as described herein. Also provided is a compound described herein for use in the prevention, treatment, or repair of a neuronal disease or disorder, wherein the compound is administered in a spinogenesis-initiating dose.

Unit Doses

[0093] In one embodiment is provided a unit dose for initiating formation of stable, functional synapses in a mammal suffering from decreased spine density and accordingly compromised functional synapses, said unit dose comprising no more than about 0.4 mg/kg/day of a compound of formula IA:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, q is from 2 to 8; and wherein said compound has a serum half-life of less than 3 hours, and further wherein said unit dose provides for formation of stable functional synapses in said mammal.

[0094] In one embodiment, the unit dose comprises from about 0.1 mg/kg/day to about 0.4 mg/kg/day. In one embodiment, the decreased functional spine density is the result of a neurological condition. In one embodiment, the unit dose is prescribed for administration once a day.

Dosage regimen

[0095] In further embodiments, the compositions and methods are provided for preventing, repairing, and/or treating a neuronal I neurodegenerative disease or disorder by inducing spinogenesis wherein the amount of drug administered is effective to provide for a concentration in the brain that induces spinogenesis and increases spines. In some embodiments, spinogenesis is induced within less than 5 minutes, less than 10 minutes, less than 30 minutes, or less than 60 minutes of administration.

[0096] Surprisingly, very small concentrations of a spinogenic compound having a half-life of less than 30 minutes (as measured in vivo in rodents), as described herein, are sufficient to induce spinogenesis. Such small concentrations have been found to provide an instructive cue to neurons to induce spinogenesis. Equally surprisingly is the fact that the induced spines are maintained for an extended period of time following administration of a small dose of a compound as described herein notwithstanding the absence of the drug from the mammal. This combination of a very short half-life and a very low dose in the brain in order to produce a prolonged effect on neurons is believed to be novel.

[0097] The dose-response curve for a compound described herein may be nonlinear. A compound described herein crosses the blood-brain barrier at a rate sufficient to initially provide a spinogenesis- initiating concentration in a brain fluid or brain tissue and then subsequently be eliminated.

[0098] In some embodiments, following the first dose, the compound, or a salt, stereoisomer, mixture of stereoisomers, or metabolite thereof, reaches its C_max in a brain fluid (e.g. serum) or brain tissue. In some embodiments, the C_max is reached in the brain within 5 to 10 minutes and then falls rather rapidly due to its short half-life. However, once initiated, spine development continues even after the concentration of the compound falls below the spinogenesis-initiating concentration in extracellular fluid. Accordingly, a single dose may induce dendritic spines that maintain over about 4 hours or more, for example, about 24 hours, about 48 hours, about 72 hours, about 96 hours, or one week following administration to the subject.

[0099] A spinogenesis-initiating concentration of a compound described herein as provided herein increases synaptic density or improve synaptic morphology in a brain region. For example, the synaptic density increase or synaptic morphology improvement may be in the hippocampus. The synaptic density increase or synaptic morphology improvement may be in the prefrontal cortex. The synaptic density increase or synaptic morphology improvement may be in the motor cortex. A spinogenesis-initiating concentration of a compound described herein as provided herein may increase the density of mushroom and/or stubby spines in a brain region, for example, the hippocampus, the prefrontal cortex, or the motor cortex, or another brain region.

[0100] To achieve the desired in vivo concentration, a spinogenesis-initiating dose of a compound described herein may be based on the weight of the subject. The effective dose to achieve a spinogenesis- initiating concentration may be determined by allometric scaling. In some embodiments, the mammal is a human and the effective dose is about 0.1 to 0.4 mg/kg. The effective dose in a human may be less than about 0.5 mg/kg, or may be about 0.2, 0.25, 0.3, 0.35, or 0.4 mg/kg/day, preferably about 0.4 mg/kg/day. The dose in a human subject may be about 0.2 to about 0.4 mg/kg. The dose may be effective in treating, preventing or repairing a neuronal disease or disorder, such as a neurodegenerative disease described herein.

[0101] Also, dosing is preferably continued on a daily schedule or a schedule of 5 days per week.

[0102] The neuronal disease or disorder may be Alexander's disease, Alper's disease, Alzheimer's disease, depression, perinatal asphyxia, Parkinson’s disease dementia (“PD dementia”), amyotrophic lateral sclerosis, ataxia telangiectasia, Batten disease (also known as Spiclmcycr-Vogt-Sjogrcn-Battcn disease), spongiform encephalopathy (e.g., bovine spongiform encephalopathy (mad cow disease), Kuru, Creutzfeldt- Jakob disease, fatal familial insomnia, Canavan disease, Cockayne syndrome, corticobasal degeneration, fragile X syndrome, frontotemporal dementia, Gerstmann-Straussler-Scheinker syndrome, Huntington's disease, HIV-associated dementia, Kennedy's disease, Krabbe's disease, Lewy body dementia, Machado- Joseph disease (Spinocerebellar ataxia type 3), multiple sclerosis, multiple system atrophy, narcolepsy, neuroborreliosis, Parkinson's disease, Pelizaeus-Merzbacher Disease, Pick's disease, primary lateral sclerosis, prion diseases, Refsum's disease, Sandhoff s disease, Schilder's disease, subacute combined degeneration of spinal cord secondary to pernicious anaemia, schizophrenia, spinocerebellar ataxia (multiple types with varying characteristics), spinal muscular atrophy, Steele- Richardson-Olszewski disease, Tabes dorsalis, drug-induced Parkinsonism, progressive supranuclear palsy, corticobasal degeneration, Progressive Bulbar Palsy (PBP), Pseudobulbar Palsy, Progressive Muscular Atrophy, Spinal Muscular Atrophy, Kennedy's Disease, multiple system atrophy, idiopathic Parkinson's disease, autosomal dominant Parkinson disease, familial, type 1 (PARK1), Parkinson disease 3, autosomal dominant Lewy body (PARK3), Parkinson disease 4, autosomal dominant Lewy body (PARK4), Parkinson disease 5 (PARK5), Parkinson disease 6, autosomal recessive early-onset (PARK6), Parkinson disease 2, autosomal recessive juvenile (PARK2), Parkinson disease 7, autosomal recessive early-onset (PARK7), Parkinson disease 8 (PARK8), Parkinson disease 9 (PARK9), Parkinson disease 10 (PARK10), Parkinson disease 11 (PARKl l), Parkinson disease 12 (PARK12), Parkinson disease 13 (PARK13), or mitochondrial Parkinson's disease. In some embodiments, the neuronal disease is Alzheimer's disease, Parkinson's disease, Parkinson’s dementia, autism, stroke, post-traumatic stress disorder (PTSD), traumatic brain disorder (TBD), chronic traumatic encephalopathy (CTE), schizophrenia, dementia (e.g., general dementia), attention-deficit/hyperactivity disorder (ADHD), amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration (FTLD) (e.g., FTLD-tau, FTLD- TDP, or FTLD-FUS), memory loss (e.g., age-related memory loss), hypertensive encephalopathy, or chronic stress.

[0103] In one preferred embodiment, the neuronal disease or disorder is a neurodegenerative disease selected from Alzheimer's disease, Parkinson's disease, ALS, frontotemporal dementia, or traumatic brain injury. [0104] In one embodiment, any one of the above diseases is excluded from the scope of this invention. roiosi In some embodiments, the neuronal disease is Alzheimer's disease (AD). Alzheimer's disease is characterized by symptoms of memory loss in the early stages of the disease. Apoe4 carriers are at greater risk of developing AD. Having experienced a traumatic brain injury (TBI) is another risk factor for developing AD, and studies indicate that those who experience a TBI have a significantly increased risk of AD. Cognitive decline has been correlated with the progressive loss of synapses. As the disease advances, symptoms include confusion, long-term memory loss, paraphasia, loss of vocabulary, aggression, irritability and/or mood swings. In more advanced stages of the disease, there is loss of bodily functions. Patients with Alzheimer's Disease (AD) demonstrate many characteristic neuropathies such as increased oxidative stress, mitochondrial dysfunction, synaptic dysfunction, disruption of calcium homeostasis, deposition of senile plaques and neurofibrillary tangles, and atrophy of the brain. AD related disorders include senile dementia of AD type (SDAT), frontotemporal dementia (FTD), vascular dementia, mild cognitive impairment (MCI) and age-associated memory impairment (AAMI). In some embodiments, a method of treating or preventing Alzheimer's disease is provided, comprising administering to a patient in need thereof a spinogenesis-initiating dose of a compound described herein. In some embodiments, the neuronal disease or disorder is selected from Alzheimer’ s disease, Parkinson’ s disease, Parkinson’s dementia, autism, fragile X syndrome, stroke, and traumatic brain injury. Surprisingly, treatment with a compound described herein may treat AD or a symptom thereof without altering A[> or Tau pathology.

[0106] The neuronal disease or disorder may be associated with a spinal cord injury, or a complication of a spinal cord injury. Spinal cord injury (SCI) may be accompanied by one or more of a number of acute complications. In some embodiments, a complication of spinal cord injury may be a respiratory complication, cardiovascular complication, hypotension, bradycardia, neurogenic shock, an autonomic dysreflexia, secondary immunodeficiency, syringomyelia, neuropathic joint arthropathy, Charcot joint arthropathy, loss of motor control, loss of sensory function, tetraplegia, paraplegia, loss of bladder control, spasm, loss of sexual function, numbness, loss of balance, autonomic dysreflexia, deep vein thrombosis, spasticity, pain, neuropathic pain, syringomyelia, neurogenic heterotopic ossification, shock, bradyarrhythmias, hypotension, ectopic beats, abnormal temperature regulation, changes in sweat secretion, vasodilatation, autonomic dysreflexia, thromboembolism, pressure ulcer, or heterotopic ossification, or a combination thereof.

[0107] The neuronal disease or disorder may be associated with a traumatic brain injury or stroke. The neuronal disease or disorder may be a psychiatric disorder such as depression or schizophrenia. In any case, the disease or disorder is one that can be treated or ameliorated by increasing the dendritic spine density in the mammal. In some embodiments, the average dendritic spine density following administration of a spinogenesis-initiating dose of a compound described herein relative to the time that treatment is initiated, increases by at least about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, 90%, or 100%, or any range between any two of the numbers, end points inclusive. The increase may be maintained for about 4 hours, about 24 hours or longer after administration of the dose.

[0108] It is believed that the instant methods provide superior benefit in stages of the neurodegenerative disease or disorder in which sufficient intact neurons remain such that new spines may form functional synapses with surrounding neurons. For example, a method provided herein may be beneficial in a patient with 0% to 20% loss of functionality (early stage disease), or with 20% to 60% loss of functionality (mid-stage disease). For example, the neuronal / neurological disease or disorder may be Alzheimer’s disease and the subject may exhibit mild cognitive impairment, mild dementia, or moderate dementia.

[0109] Amyotrophic Lateral Sclerosis (ALS) may be staged according to the symptomology of the patient. One staging system that is used is the Amyotrophic Lateral Sclerosis Functional Rating Scale - Revised (ALSFRS-R). The ALSFRS provides a physician-generated estimate of the patient’s degree of functional impairment, which can be evaluated to assess progression of the disease. The ALSFRS-R includes twelve questions that ask the physician to rate his/her impression of the patients level of functional impairment in performing twelve common tasks including speech, salivation, swallowing, handwriting, cutting food, dressing and hygeine, turning in bed, walking, climbing stairs, dyspnea, orthopnea, and respiratory insufficiency. Each task is rated on a five-point scale from 0 = can't do, to 4 = normal ability. Individual item scores are summed to produce a reported score of between 1 (least functional) and 48 (normal function). (A score of zero would indicate unreasonable incapacitation.) In some embodiments, the neuronal disease or disorder is Amyotrophic Lateral Sclerosis and the subject has an ALSFRS-R score of 38 to 47. In some embodiments, the neuronal disease or disorder is Amyotrophic Lateral Sclerosis and the subject has an ALSFRS-R score of 20 to 38.

[0110] ALS clinical stages are defined by central nervous system region involvement with weakness, wasting, spasticity, dysphagia or dysarthria, and with regions defined in the same way as for the El Escorial criteria. Involvement of a single CNS region (symptom onset) is Stage 1, a second CNS region is Stage 2, and three CNS regions define Stage 3. Respiratory involvement sufficient to require ventilatory support, or swallowing impairment sufficient to require gastrostomy, defines Stage 4. Stage 5 is death. In some embodiments, the neuronal disease or disorder is Amyotrophic Lateral Sclerosis and the subject is clinical Stage 1 or Stage 2. In some embodiments, the neuronal disease or disorder is Amyotrophic Lateral Sclerosis and the subject is clinical Stage 1, Stage 2 or Stage 3.

[0111] Traumatic brain injuries (TBI) are classified as mild, moderate and severe. A mild form of traumatic brain injury is a concussion. These can be caused by a bump, blow, or jolt to the head or body that makes the brain move rapidly inside the skull. Even if there is no loss of consciousness, a mild traumatic brain injury or mTBI is diagnosed when the person has any loss of memory for events immediately before or after the injury. Symptoms of mild traumatic brain injury include: Headache; Dizziness; Insomnia; decreased concentration and attention span; Depression; Anxiety; Mood swings; Impaired balance; Decreased speed of information processing; Decreased ability to learn new things and recall. With a moderate traumatic brain injury, there are usually abnormal CT, PET or MRI findings after the injury. Loss of consciousness may have lasted a few minutes to a few hours. People who experience a moderate TBI normally have confusion lasting a few days to weeks. However, physical, cognitive and/or behavioral impairments could last for months or be permanent. A severe traumatic brain injury usually involves a prolonged unconscious state or coma that lasts days, weeks, or months. Symptoms of severe traumatic brain injury can include loss of consciousness, headache, nausea, vomiting, lack of coordination, dizziness, trouble with balance, dilation of one or more pupils, slurred speech, behavioral or mood changes, loss of coordination, restlessness and agitation. Patients with severe TBI can make significant improvements, including return to a life very similar to what they had before the injury. However, some are left with permanent physical, cognitive, or behavioral impairments. With severe traumatic brain injury, rehabilitation is almost always a necessity. In some embodiments the neuronal disease or disorder is traumatic brain injury and the patient has suffered mild traumatic brain injury or moderate traumatic brain injury but not severe traumatic brain injury.

[0112] For traumatic brain injury, the process of recovery has three stages, in the first the patient is unconscious, in the second he or she regains full consciousness signified by the end of the period of post traumatic amnesia and continues to show evidence of rapid improvement in basic physical and mental functions; The rate of recovery shows within six months of injury in most cases and this represents the end of the second stage; In the third stage, which may last for many months, both the patient and his or her relatives adapt to the residual disabilities of the former. See Bond, The stages of recovery from severe head injury with special reference to late outcome, Int. Rehabil. Med. (1979) Vol. 1(4): 155-9. Thus, in some embodiments the neuronal disease or disorder is traumatic brain injury and the patient is second stage recovery or third stage recovery.

[0113] In some embodiments, the dendritic spine density following administration of a spinogenesis- initiating dose of a compound described herein, relative to the time that treatment with a compound described herein, is initiated, increases by about 20% to about 100%.

[0114] In some embodiments, the time to realize a change in spine density or spine morphology described herein, for example, average dendritic spine density, average spine density, or average number of spines per neuron, is as little as 5 minutes, for example, 30 minutes, 45 minutes, 60 minutes, or 4 hours. The change in spine density is maintained for at least about 4 hours, about 24 hours, about 48 hours, or about 72 hours following administration. Compounds roiisi In some embodiments, the compound is a compound described in International Patent

Publication No. WO 2019/028164. In some embodiments, the compound is a compound of formula I

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, wherein R is hydrogen, C1-C4 alkyl, halo, hydroxyl, amino, cyano or nitro; and q is from 2 to 8.

[0116] In some embodiments, provided is a compound, or a pharmaceutically acceptable salt or solvate thereof, selected from:

p .

[0117] The efficacy of Compound 1 to promote spinogenesis in mice with spinal cord injuries has also been demonstrated in a recent study by Fogarty et al., “Novel regenerative drug, SPG302 promotes functional recovery of diaphragm muscle activity after cervical spinal cord injury”, The Journal of Physiology 0.0 (2023) pp 1-20.

Combination Therapies

[0118] In one embodiment, a dose as described herein of a compound described herein may be used in combination with one or more additional therapeutic agent that are being used and/or developed to treat a neuronal disease or disorder.

[0119] When used for the treatment or prevention of the diseases and disorders described above, a dose as described herein of a compound described herein, or a pharmaceutical composition thereof, may be administered together with one or more additional therapeutic agents, for example additional therapeutic agents approved for use in the treatment or prevention of the particular disease or disorder, and more particularly agents considered to form the current standard of care. Where combination therapy is envisaged, the active agents may be administered simultaneously, separately or sequentially in one or more pharmaceutical compositions.

[0120] Recent strategies for the treatment of AD that may be combined with a method provided herein include controlling the production or the aggregation state of specific isoforms of Ap peptides.

Additional strategies include preventing, reducing or removing toxic forms of phosphorylated tau. Other strategies involve small molecule targeting of enzymes that play a role in production of A peptides through processing of amyloid precursor protein in an attempt to lower the abundance of Ap peptides in the brain. Additionally, there is accruing information on the role of non-amyloid neuropathies such as tauopathy or sporadic inheritance of specific mutations in the apolipoprotein E gene, which is stimulating the development of additional strategies to combat neurodegeneration.

[0121] The one or more additional therapeutic agent may be tacrine, donepezil, galantamine, rivastigmine, memantine, levodopa, carbidopa, lisuride, rasagiline, tolcapone, entacapone, clozapine, desipramine, citalopram, nortriptyline, paroxetine, atomoxetine, venlafaxine, amantadine, donepezil, rivastigmine, bromocriptine, cabergoline, pergolide, pramipexole, ropinirole, rotigotine, apomorphine, benserazide, selegiline, omigapil, CEP- 1347, isradipine, DOPA, lithium, riluzole, levetiracetam, ezogabine, pregabalin, rufmamide, felbamate, carbamazepine, valproate, sodium valproate, lamotrigine, phenytoin, oxcarbazepine, ethosuximide, gabapentin, tiagabine, topiramate, vigabatrin, phenobarbital, primidone, clonazepam, interferon beta-la, interferon beta-lb, mitoxantrone, natalizumab, fmgolimod, natalizumab, teriflunomide, dimethyl fumarate, glatiramer, ATOH1 gene therapy, ozanezumab, arimoclomol, tirasemtiv, dexpramipexole, pridopidine, or galantamine; or a phosphoglycerate kinase (PGK) as described in US 2018/0147263. Tn some embodiments, the one or more additional therapeutic agent may be an acetyl-cholinesterase inhibitor (AChEI), for example, acotiamide, alpha-pinene, ambenonium, demecarium, DFP (diisopropylfluorophosphate), donepezil, edrophonium, galantamine, huperzine A, lactucopicrin, ladostigil, neostigmine, physostigmine, pyridostigmine, dyflos, echothiophate, rivastigmine, rosmarinic acid, tacrine, ungeremine, zanapezil, ganstigmine, phenserine, phenethylnorcymserine (PENC), cymserine, thiacymserine, SPH 1371 (galantamine plus), ER 127528, RS 1259, or F3796. In some embodiments, the one or more additional therapeutic agent may be an amyloid-clearing antibody, for example, bapineuzumab, solanezumab, gantenerumab, crenezumab, ponczumab, BAN2401, or aducanumab.

[0122] The one or more additional therapeutic agents may be a sedative -hypnotic such as chloral hydrate, estazolam, flurazepam hydrochloride, pentobarbital, pentobarbital sodium, phenobarbital sodium, secobarbital sodium, temazepam, triazolam, zaleplon, or zolpidem tartrate; an anticonvulsant such as acetazolamide sodium, carbamazepine, clonazepam, clorazepate dipotassium, diazepam, divalproex sodium, ethosuximde, fosphenytoin sodium, gabapentin, lamotrigine, magnesium sulfate, phenobarbital, phenobarbital sodium, phenytoin, phenytoin sodium, primidone, tiagabine hydrochloride, topiramate, valproate sodium, or valproic acid; an antidepressant such as amitriptyline hydrochloride, amitriptyline pamoate, amoxapine, bupropion hydrochloride, citalopram hydrobromide, clomipramine hydrochloride, desipramine hydrochloride, doxepin hydrochloride, fluoxetine hydrochloride, imipramine hydrochloride, imipramine pamoate, mirtazapine, nefazodone hydrochloride, nortriptyline hydrochloride, paroxetine hydrochloride, phenelzine sulfate, sertraline hydrochloride, tranylcypromine sulfate, trimipramine maleate, or venlafaxine hydrochloride; an antianxiety drug such as alprazolam, buspirone hydrochloride, chlordiazepoxide, chlordiazepoxide hydrochloride, clorazepate dipotassium, diazepam, doxepin hydrochloride, hydroxyzine embonate, hydroxyzine hydrochloride, hydroxyzine pamoate, lorazepam, mephrobamate, midazolam hydrochloride, or oxazepam; an antipsychotic drug such as chlorpromazine hydrochloride, clozapine, fluphenazine decanoate, fluephenazine enanthate, fluphenazine hydrochloride, haloperidol, haloperidol decanoate, haloperidol lactate, loxapine hydrochloride, loxapine succinate, mesoridazine besylate, molindone hydrochloride, olanzapine, perphenazine, pimozide, prochlorperazine, quetiapine fumarate, risperidone, thioridazine hydrochloride, thiothixene, thiothixene hydrochloride, or trifluoperazine hydrochloride; a central nervous system stimulant such as amphetamine sulfate, caffeine, dextroamphetamine sulfate, doxapram hydrochloride, methamphetamine hydrochloride, methylphenidate hydrochloride, modafinil, pemoline, or phentermine hydrochloride; an antiparkinsonian such as amantadine hydrochloride, benztropine mesylate, biperiden hydrochloride, biperiden lactate, bromocriptine mesylate, carbidopa-levodopa, entacapone, levodopa, pergolide mesylate, pramipexole dihydrochloridc, ropinirolc hydrochloride, selegiline hydrochloride, tolcapone, or trihexyphenidyl hydrochloride; or a central nervous system agent such as bupropion hydrochloride, donepezil hydrochloride, droperidol, fluvoxamine maleate, lithium carbonate, lithium citrate, naratriptan hydrochloride, nicotine polacrilex, nicotine transdermal system, propofol, rizatriptan benzoate, sibutramine hydrochloride monohydrate, sumatriptan succinate, tacrine hydrochloride, or zolmitriptan; a cholinergic (e.g., parasymathomimetic) such as bethanechol chloride, edrophonium chloride, neostigmine bromide, neostigmine methylsulfate, physostigmine salicylate, or pyridostigmine bromide; an anticholinergic such as atropine sulfate, dicyclomine hydrochloride, glycopyrrolate, hyoscyamine, hyoscyamine sulfate, propantheline bromide, scopolamine, scopolamine butylbromide, or scopolamine hydrobromide; an adrenergic (sympathomimetics) such as dobutamine hydrochloride, dopamine hydrochloride, metaraminol bitartrate, norepinephrine bitartrate, phenylephrine hydrochloride, pseudoephedrine hydrochloride, or pseudoephedrine sulfate; an adrenergic blocker (sympatholytic) such as dihydroergotamine mesylate, ergotamine tartrate, methysergide maleate, or propranolol hydrochloride; a skeletal muscle relaxant such as baclofen, carisoprodol, chlorzoxazone, cyclobenzaprine hydrochloride, dantrolene sodium, methocarbamol, or tizanidine hydrochloride; a neuromuscular blocker such as atracurium besylate, cisatracurium besylate, doxacurium chloride, mivacurium chloride, pancuronium bromide, pipecuronium bromide, rapacuronium bromide, rocuronium bromide, succinylcholine chloride, tubocurarine chloride, or vecuronium bromide; or a corticosteroid such as betamethasone, betamethasone acetate or betamethasone sodium phosphate, betamethasone sodium phosphate, cortisone acetate, dexamethasone, dexamethasone acetate, dexamethasone sodium phosphate, fludrocortisone acetate, hydrocortisone, hydrocortisone acetate, hydrocortisone cypionate, hydrocortisone sodium phosphate, hydrocortisone sodium succinate, methylprednisolone, methylprednisolone acetate, methylprednisolone sodium succinate, prednisolone, prednisolone acetate, prednisolone sodium phosphate, prednisolone tebutate, prednisone, triamcinolone, triamcinolone acetonide, or triamcinolone diacetate.

Kits

[0123] Provided herein are also kits that include a spinogenesis-initiating dose of a compound described herein, or a pharmaceutical composition thereof, optionally a second active agent, and suitable packaging. In one embodiment, a kit further includes instructions for use. In one aspect, a kit includes a spinogenesis-initiating dose of a compound described herein, or a pharmaceutical composition thereof, and a label and/or instructions for use of the pharmaceutical composition in the treatment of a neuronal disease or disorder described herein.

[0124] Provided herein are also articles of manufacture that include a spinogenesis-initiating dose of a compound described herein, or a pharmaceutical composition thereof, in a suitable container. The container may be a vial, jar, ampoule, preloaded syringe, nebulizer, aerosol dispensing device, dropper, or intravenous bag.

Pharmaceutical Compositions and Modes of Administration

[0125] A spinogenesis-initiating dose of a compound described herein may be administered in the form of pharmaceutical compositions. Thus, provided herein are also pharmaceutical compositions that contain a spinogenesis-initiating dose of a compound described herein and one or more pharmaceutically acceptable excipients. Suitable pharmaceutically acceptable excipients may include, for example, inert solid diluents and fillers, diluents, including sterile aqueous solution and various organic solvents, permeation enhancers, solubilizers and adjuvants. Such compositions are prepared in a manner well known in the pharmaceutical art. See, e.g., Remington’s Pharmaceutical Sciences, Mace Publishing Co., Philadelphia, Pa. 17th Ed. (1985); and Modern Pharmaceutics, Marcel Dekker, Inc. 3rd Ed. (G.S. Banker & C.T. Rhodes, Eds.).

[0126] The pharmaceutical composition may be administered by various methods including, for example, nasal, rectal, buccal, intranasal and transdermal routes. In certain some embodiments, the pharmaceutical composition may be administered by intra-arterial injection, intravenously, intraperitoneally (“i.p.”), parenterally, intramuscularly, subcutaneously, orally, topically, or as an inhalant. [0127] One mode for administration is parenteral, for example, by injection. The forms in which the pharmaceutical compositions described herein may be incorporated for administration by injection include, for example, aqueous or oil suspensions, or emulsions, with sesame oil, corn oil, cottonseed oil, or peanut oil, as well as elixirs, mannitol, dextrose, or a sterile aqueous solution, and similar pharmaceutical vehicles.

[0128] Oral administration may be another route for administration of the compositions described herein. Administration may be via, for example, capsule or enteric coated tablets. In making the pharmaceutical compositions that include at least one compound described herein or a pharmaceutically acceptable salt or solvate thereof, the active ingredient is usually diluted by an excipient and/or enclosed within such a carrier that can be in the form of a capsule, sachet, paper or other container. When the excipient serves as a diluent, it can be in the form of a solid, semi-solid, or liquid material, which acts as a vehicle, carrier or medium for the active ingredient. Thus, the compositions can be in the form of tablets, pills, powders, lozenges, sachets, cachets, elixirs, suspensions, emulsions, solutions, syrups, aerosols (as a solid or in a liquid medium), ointments containing, for example, up to 10% by weight of the active compound, soft and hard gelatin capsules, sterile injectable solutions, and sterile packaged powders.

[0129] Some examples of suitable excipients include lactose, dextrose, sucrose, sorbitol, mannitol, starches, gum acacia, calcium phosphate, alginates, tragacanth, gelatin, calcium silicate, microcrystalline cellulose, polyvinylpyrrolidone, cellulose, sterile water, syrup, and methyl cellulose. The formulations can additionally include lubricating agents such as talc, magnesium stearate, and mineral oil; wetting agents; emulsifying and suspending agents; preserving agents such as methyl and propylhydroxybenzoates; sweetening agents; and flavoring agents.

[0130] The pharmaceutical composition and any container in which it is distributed may be sterilized. The pharmaceutical composition may also contain adjuvants such as preservatives, stabilizers, emulsifiers or suspending agents, wetting agents, salts for varying the osmotic pressure, viscosity alerting agents, or buffers.

[0131] The compositions that include at least one compound described herein, such as a compound described herein, or a pharmaceutically acceptable salt or solvate thereof can be formulated so as to provide quick, sustained or delayed release of the active ingredient after administration to the subject by employing procedures known in the art. Controlled release drug delivery systems for oral administration include osmotic pump systems and dissolutional systems containing polymer-coated reservoirs or drug- polymer matrix formulations. Examples of controlled release systems are given in U.S. Patent Nos. 3,845,770; 4,326,525; 4,902,514; and 5,616,345. Another formulation for use in the methods disclosed herein employ transdermal delivery devices (“patches”). Such transdermal patches may be used to provide continuous or discontinuous infusion of the compounds described herein in controlled amounts. The construction and use of transdermal patches for the delivery of pharmaceutical agents is well known in the art. See, e.g., U.S. Patent Nos. 5,023,252, 4,992,445 and 5,001,139. Such patches may be constructed for continuous, pulsatile, or on demand delivery of pharmaceutical agents.

[0132] For preparing solid compositions such as tablets, the principal active ingredient may be mixed with a pharmaceutical excipient to form a solid preformulation composition containing a homogeneous mixture of a compound described herein or a pharmaceutically acceptable salt or solvate thereof. When referring to these preformulation compositions as homogeneous, the active ingredient may be dispersed evenly throughout the composition so that the composition may be readily subdivided into equally effective unit dosage forms such as tablets, pills and capsules.

[0133] The tablets or pills of the compounds described herein may be coated or otherwise compounded to provide a dosage form affording the advantage of prolonged action, or to protect from the acid conditions of the stomach. For example, the tablet or pill can include an inner dosage and an outer dosage component, the latter being in the form of an envelope over the former. The two components can be separated by an enteric layer that serves to resist disintegration in the stomach and permit the inner component to pass intact into the duodenum or to be delayed in release. A variety of materials can be used for such enteric layers or coatings, such materials including a number of polymeric acids and mixtures of polymeric acids with such materials as shellac, cetyl alcohol, and cellulose acetate.

[0134] The pharmaceutical composition may be formulated for nasal administration. Such pharmaceutical compositions may include one or more active ingredients, such as a compound described herein, or a pharmaceutically acceptable salt or solvate thereof, in varying physical states. For example, the active ingredients may be dissolved or suspended in a liquid carrier. The active ingredients may be in a dry form. The dry form may be a powder. Active ingredients in a powder may be amorphous or crystalline. For example, a compound described herein, or a pharmaceutically acceptable salt or solvate thereof, may be amorphous or crystalline. The crystalline active material may be a hydrate or a solvate.

[0135] Solid compounds, or a salt or crystal thereof, may be present in a formulation in a selected average particle size. The particles may have an average particle size (in longest dimension) of 10 nm, 100 nm, 300 nm, 500 nm, 1 pm, 10 pm, 50 pm, 100 pm, 300 pm, or 500 pm, or a range between any two values.

[0136] Administration may be by inhalation or insufflation. Compositions for inhalation or insufflation may include solutions and suspensions in pharmaceutically acceptable, aqueous or organic solvents, or mixtures thereof, and powders. The liquid or solid compositions may contain suitable pharmaceutically acceptable excipients as described herein. In some embodiments, the compositions are administered by the oral or nasal respiratory route. Effects may be local or systemic. In a particular embodiment, the effect is local to cranial tissues. In other embodiments, compositions in pharmaceutically acceptable solvents may be nebulized by use of inert gases. Nebulized solutions may be inhaled directly from the nebulizing device or the nebulizing device may be attached to a facemask tent, or intermittent positive pressure breathing machine. Solution, suspension, or powder compositions may be administered, preferably orally or nasally, from devices that deliver the formulation in an appropriate manner. A pharmaceutical composition for inhalation or insufflation may be an aerosol.

[0137] The pharmaceutical composition may comprise a liquid suspension or solution comprising about 0.05%, about 0.1%, about 0.3%, about 0.5%, about 0.7%, about 1%, about 2%, about 3%, about 4%, or about 5% w/w of active ingredients. The liquid may comprise water and/or an alcohol. The liquid may include a pH adjusting agent such that the pH is about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, or about 10, or a range of values therebetween.

[0138] The pharmaceutical composition may comprise a pharmaceutically acceptable preservative. Preservatives suitable for use herein include, but are not limited to, those that protect the solution from contamination with pathogenic particles, including phenylethyl alcohol, benzalkonium chloride, benzoic acid, or benzoates such as sodium benzoate. In certain some embodiments, the pharmaceutical composition comprises from about 0.01% to about 1.0% w/w of benzalkonium chloride, or from about 0.01% and about 1% v/w phenylethyl alcohol. Preserving agents may also be present in an amount from about 0.01% to about 1%, preferably about 0.002% to about 0.02% by total weight or volume of the composition.

[0139] The pharmaceutical composition may also comprise from about 0.01% to about 90%, or about 0.01% to about 50%, or about 0.01% to about 25%, or about 0.01% to about 10%, or about 0.01% to about 1% w/w of one or more of an emulsifing agent, a wetting agent or a suspending agent. Such agents for use herein include, but are not limited to, polyoxyethylene sorbitan fatty esters or polysorbates, including, but not limited to, polyethylene sorbitan monoolcatc (Polysorbate 80), polysorbate 20 (polyoxyethylene (20) sorbitan monolaurate), polysorbate 65 (polyoxyethylene (20) sorbitan tristearate), polyoxyethylene (20) sorbitan mono-oleate, polyoxyethylene (20) sorbitan monopalmitate, polyoxyethylene (20) sorbitan monostearate; lecithins; alginic acid; sodium alginate; potassium alginate; ammonium alginate; calcium alginate; propane- 1,2-diol alginate; agar; carrageenan; locust bean gum; guar gum; tragacanth; acacia; xanthan gum; karaya gum; pectin; amidated pectin; ammonium phosphatides; microcrystalline cellulose; methyl cellulose; hydroxypropylcellulose; hydroxypropylmethylcellulose; ethylmethylcellulose; carboxymethylcellulose; sodium, potassium and calcium salts of fatty acids; mono-and di-glycerides of fatty acids; acetic acid esters of mono- and diglycerides of fatty acids; lactic acid esters of mono-and di-glycerides of fatty acids; citric acid esters of mono-and di-glycerides of fatty acids; tartaric acid esters of mono-and di-glycerides of fatty acids; mono- and diacetyltartaric acid esters of mono-and di-glycerides of fatty acids; mixed acetic and tartaric acid esters of mono-and di-glycerides of fatty acids; sucrose esters of fatty acids; sucroglycerides; polyglycerol esters of fatty acids; polyglycerol esters of polycondensed fatty acids of castor oil; propane - 1,2-diol esters of fatty acids; sodium stearoyl-21actylate; calcium stearoyl-2-lactylate; stearoyl tartrate; sorbitan monostearate; sorbitan tristearate; sorbitan monolaurate; sorbitan monooleate; sorbitan monopalmitate; extract of quillaia; polyglycerol esters of dimerised fatty acids of soya bean oil; oxidatively polymerised soya bean oil; and pectin extract.

[0140] In a further embodiment, the pharmaceutical composition for nasal administration may be provided in the form of a powder. For example, a powdery nasal composition can be directly used as a powder for a unit dosage form. If desired, the powder can be filled in capsules such as hard gelatine capsules. The contents of the capsule or single dose device may be administered using e.g. an insufflator.

[0141] Thus, a method for treating a neuronal disease or disorder may include the step of administering nasally a pharmaceutical composition comprising a compound described herein, or a salt thereof, to a subject in need thereof.

EXAMPLES

Example 1

Transgenic mice and treatment protocol

[0142] Female homozygous 6 months old 3xTg-AD and wild-type (WT) mice were used in the study. The characterization of the 3xTg-AD mice has been described previously. Oddo, S., et al. (2003). Triple- transgenic model of Alzheimer’s disease with plaques and tangles: intracellular Abeta and synaptic dysfunction, Neuron 39, 409-21. Additional procedures found in Trujillo-Estrada, et al. (2019).

[0143] Two different doses of Compound 1 were used: 3 mg/kg and 30 mg/kg. 3xTg-AD and WT mice were randomly divided into groups (n=8-ll): WT vehicle (n=ll), 3xTG-AD vehicle (n=10), 3xTG-AD Compound 1, 3 mg/kg (n=10), 3xTG-AD Compound 1, 10 mg/kg (n=l 1), 30 mg/kg (n=10). Compound 1 (dissolved in 5% dimethyl sulfoxide (DMSO) and diluted with phosphate buffered saline (PBS) to 5% DMSO) was administered by intraperitoneal injection once daily for 4 weeks. Animals treated with vehicle (5% DMSO in PBS) were used as a negative control group. WT mice were used as a comparator to confirm neurodegeneration in the 3xTG-AD mice. After all behavior experiments were completed, the mice were euthanized.

[0144] After euthanasia, the animals were perfused transcardially with 0.1M phosphate-buffered saline pH 7.4. Next, a hemisphere of the brain was stained with Golgi solution using superGolgi Kit (Bioenno Tech LLC, Santa Ana, CA) and the other hemisphere used to prepare synaptosomes and for immunohistochemistry as described below. Golgi Stain of Dendritic Spines

[0145] Brains were incubated for 11-days in impregnation solutions, followed by 2-days incubation in a post-impregnation solution. Once the impregnation of neurons was complete, thick (150 pm) free- floating sections were obtained using a HA752 vibratome (Campden Instruments Ltd, Lafayette, IN) and serially collected in a mounting buffer. Sections mounted on coated slides were stained and post-stained respectively for 20 min, dehydrated in graded ethanol, cleared with xylene and coverslipped with DPX (VWR, Visalia, CA, USA) mounting medium.

Dendritic Spine Analysis

[0146] Stereological quantifications were performed using Neurolucida software from Microbrightfield Bioscience (MBF Bioscience, Williston, VT, USA) to determine the number of spines in the stratum radiatum (sr) of the hippocampal CAI region and in the prefrontal cortex. Briefly, every second section was used through the entire antero-posterior extent of each region of interest. Spines were counted using a 100x/1.4 objective (5-6 sections per animal, n=5 animals per group).

Synaptosome extracts

[0147] Briefly, the hippocampus from the non-Golgi treated hemisphere was homogenized (using a Dounce homogenizer) in DEPC-treated water (Ambion) supplemented with 0.32 M sucrose, 20 mM Tris- HC1, 0.5 M EDTA and 0.5 M EGTA (pH 7.4), containing complete protease (Sigma) and phosphatase inhibitor cocktails (Sigma). After homogenization, the crude synaptosomal fraction (synaptosomes plus mitochondria) was isolated by two sequential centrifugations (l,500xg, 10 min followed by 12,500xg, 20 min; at 4°C). The protein content of the synaptosomal fractions was determined using the Bradford assay. For Western blots (WB) experiments, synaptosomal preparations were temporally stored at -80°C.

Immunoblotting

[0148] Equal amounts of protein (20 pg) were separated on 10% Bis-Tris gel (Invitrogen, Carlsbad, CA) and transferred to nitrocellulose membranes. Membranes were blocked for 1 hour in 5% (w/v) suspension of Bovine Serum Albumin (BSA; Gemini Bio-Products, West Sacramento, CA, USA) in 0.2% Tween 20 Tris-buffered saline (pH 7.5). After blocking, the membranes were incubated overnight at 4°C with one of the following primary antibodies: anti-Drebrin (1:1000; Enzo Life Sciences), anti- GluAl (1:1000; Cell Signaling), anti-p-GluAl (Ser845; 1:1000; Cell Signaling), anti-postsynaptic density protein 95 (PSD95; 1:1000; Cell Signaling), anti-synaptic vesicle glycoprotein 2 (SV2A; 1:1000; Abeam), anti-fascin (1:1000; Abeam), anti-p-fascin (1:1000; Abeam), anti-synaptophysin (1:2000; Abeam), anti- -tubulin (1:5000; Cell Signaling). The membranes were washed in tween-TBS for 20 min and incubated at 20°C with the specific secondary antibody at a dilution of 1 : 10000 (Pierce Biotechnology) for 60 min. The blots were developed using Super Signal (ThermoFisher Scientific, Rockford, IL, USA).

Immunohistochemistry

[0149] Coronal free-floating sections (40p.m thick) were pretreated with 3% H2C>2/3% methanol in Trisbuffered saline (TBS) for 30 min to block endogenous peroxidase activity. After TBS wash, sections were incubated first in TBS with 0.1% Trition X-100 (TBST) for 15 min, and then in TBST with 2% bovine serum albumin (BSA, Sigma-Aldrich) for 30 min. Sections were incubated with 6E10 (1:1000; BioLegend, San Diego, CA, USA), anti-HT7 (1:500; Thermo Scientific) and anti-AT180 (1:500; Thermo Scientific), in TBS + 5% normal horse serum overnight at room temperature. Sections were then incubated with biotinylated anti-mouse, 1:500 in TBS + 2%BSA + 5% normal serum for Ihr at 20°C, followed by Vector ABC Kit and DAB reagents (Vector Laboratories, Burlingame, CA, USA) to visualize staining.

[0150] For double fluorescent stain, sections were incubated with anti-PSD95 (1:250; Invitrogen) and anti-synaptophysin (1:700; Sigma) overnight at 4°C. Next, sections were incubated in secondary goat anti-mouse alexa-fluor 555 for synaptophysin and goat anti-rabbit alexa-fluor 488 for PSD95 antibody (Invitrogen) for 1 hour. Sections were then mounted and coverslipped with Fluoromount-G (Southern Biothech).

Quantitative analyses

[0151] The biochemical data were quantitatively analyzed using Image J 1.36b software. For synaptophysin/PSD95 quantification, fluorescent sections were imaged with a Leica DM 2500 laser scanning confocal with identical laser and detection settings. Using a 63x oil objective (zoom=4), a Z stacks (0.34 pm interval, within a depth of 3 pm) for each section (6 sections per animal, n=5) were collected per area of interest (CAI, stratum radiatum). Number of synaptic puncta and colocalization between PSD95 and synaptophysin puncta (number of colocalized spots at a distance of 200 nm or less) were quantified using Bitplane Imaris software (spots function).

Ap and tau ELISA

[0152] Levels of Af> and Tau were measured using the V-Plex A[3 peptide panel 1 kit and phospho- Thr231/total tau kit, respectively. For AP ELISA, 150 pl/well of Diluent 35 was added in a plate and incubated for 1 hour at room temperature. After the washes, 25 pl of detection antibody solution and 25 pl of samples (soluble fraction, SI), calibrators or controls, were added to each well and incubated for 24 h at 4 Celsius degree. Then, samples were washed, 150 pl of Read buffer were added to each well and the plate was read in the MESO QuickPlex SQ 120 instrument. For tau ELISA, 150 pl/well of Blocker A solution were first added and incubated for 1 hour at room temperature. Then, the plate was washed and 25 pl of calibrator or samples were added in each well. Next, the plate was washed and incubated in the detection antibody solution (25 pl) for 1 hour at room temperature. Finally, samples were washed, added 150 pl of Read buffer and read in the MESO QuickPlex SQ 120 instrument. The data obtained were normalized with the protein concentration of each sample.

In vitro assay

[0153] Briefly, neurons from the hippocampus of 3 newborn rats were cultured and plated in a 24-well plate and were cultured for 14 days. At day 1, the culture medium was replaced with plain medium. At day 4, 5 nM of araC was added in order to stop glial cell mitosis and to avoid background staining, multidimensional plains of focus and excessive nutrient consumption. At day 14, Compound 1 was added to the culture wells in several concentrations (0.1, 0.3, 1, 3 and 10 pM) using 0.1% DMSO as a solvent. At day 15, cells were fixed on coverslips using methanol and double-stained with antibody against PSD95 for synaptic count of spines on the basal dendrites and antibody against synaptobrevin II for presynaptic imaging. DAPI staining was used for cell nuclei count. The number of spines per 20 pm length of dendrite was compared to the untreated control group. Vehicle group was treated with 0.1% DMSO.

[0154] For immunocytochemistry, coverslips with primary rat hippocampal neurons at day 15 were fixed with 100% frozen methanol and permeabilized with 0.02% Triton X-100. Neurons were then incubated in BSA for Ih at room temperature followed by incubation with respective antibodies: mouse- anti-PSD95 (Thermofisher) and rabbit-anti-Synaptobrevin II (SYSY). Later on, secondary antibodies Alexa Fluor 488-conjugated anti mouse antibody and Alexa Fluor 594-conjugated anti rabbit antibody. Coverslips were mounted on slides using fluorescent mounting medium with DAPI (Gbi). Approximately 10 images from different areas of a total of 3 coverslips per treatment group were taken. Imaging was done using BX43 Olympus microscope driven by the standard “CellSens” software by Olympus. Images were taken under 60X water-dipping objective using DP74 camera (Olympus). Dendritic spines were detected automatically using ImageJ software. To perform analysis on the PSD95 content puncta, an exclusion threshold was set at 5 points above the background. Irrelevant content, such as cell bodies, glia and synapses out of the focus plain were dimmed. To estimate the neurites length, an ImageJ plugin - “NeuronJ” was used.

Statistical analyses

[0155] All experiments were conducted blinded, and data were analyzed by one-way or two-way analysis of variance (ANOVA), followed by Tukey’s comparisons using Graphpad Prism 8® software (Graphpad Prism Inc., San Diego, CA, USA). The significance was set at 95% of confidence. All values are presented as mean ± SEM. Results

[0156] The in vivo experiments demonstrate that Compound 1 treatment mitigates the behavioral impairments in 3xTg-AD mice. To evaluate the cognitive effects of Compound 1, WT and 3xTg-AD mice at 6 months of age were dosed daily for 4 weeks with either vehicle or Compound 1 at 3 or 30mg/kg (i.p.), with behavioral assessments conducted during the 4^th week, followed by sacrifice for performance of histological and biochemical assays in brains from the same animals. To assess whether Compound 1 rescues cognitive function in 3xTg-AD mice, we evaluated spatial memory in vehicle and Compound 1-treated WT and 3xTg-AD mice using the Morris water maze test (Fig. 1). 3xTg-AD mice treated with vehicle showed severe impairments in learning during acquisition of the spatial task compared to vehicle-treated WT mice. These deficits were reversed by Compound 1 treatment at both 3- and 30-mg/kg doses (Fig. 1). In addition, mice were tested 24 hours after the last training trial to evaluate memory retention. Vehicle-treated 3xTg-AD mice displayed significant impairments in retention as measured by the frequency of visits to, and time spent in, the target area (Fig. 2A-2B). Treatment of 3xTg-AD mice with Compound 1 at 3- and 30-mg/kg significantly improved memory retention in these assays. Moreover, the cognitive impairments observed in 3xTg-AD vehicle mice were not attributed to motor deficits, since no significant changes were noted for distance traveled and velocity (Fig. 2C-2D) in any of the treatment groups (including WT and 3xTg-AD mice).

10157] To further characterize the memory enhancing effects of Compound 1 in 3xTg-AD mice, the contextual fear conditioning (CFC) paradigm was used, another hippocampal-dependent task (Fig. 3). Vehicle-treated 3xTg-AD mice showed a markedly reduced freezing response to the conditioning context compared to WT vehicle mice. The duration of the freezing response was significantly increased after Compound 1 treatment in 3xTg-AD mice and was similar to WT levels. Overall, these data suggest that Compound 1 reverses hippocampal learning and memory deficits in 3xTg-AD mice.

[0158] The experiments show Compound 1 restores the numbers of postsynaptic puncta and their colocalization with presynaptic elements in 3xTg-AD mice. We next evaluated whether the Compound 1- induced improvement of 3xTg-AD mice in hippocampal-dependent memory tasks was associated with changes in pre- and postsynaptic protein puncta in the stratum radiatum of hippocampal field CAI using immunofluorescence microscopy. Analysis of sections immunolabeled for the postsynaptic scaffolding protein, PSD95, revealed a significant deficit in the number of postsynaptic puncta (Fig. 4 panels Ala- Ald and Fig. 5A) in 3xTg-AD mice treated with vehicle (Fig. 4 panel Alb) compared to WT vehicle mice (Fig. 4 panel Ala). The postsynaptic puncta were restored by Compound 1 treatment at both 3 and 30mg/kg doses (Fig. 4 panels Ale and Aid). Decreases in the number of presynaptic elements containing synaptophysin in 3xTg-AD mice were also observed, but this was not rescued by Compound 1 treatment at 3- or 30-mg/kg (Fig. 4 panels A2a-A2d and Fig. 5B). However, Compound 1 treatment (at 30mg/kg) did rescue deficits in the colocalization of PSD95- and synaptophysin-labeled elements (Fig. 4 panels A3a-A3d) in 3xTg-AD mice at 30 mg/kg mice (Fig. 5C), considered an immunohistochemical measure of functional synapses.

[0159] The experiments show Compound 1 reverses large decreases in dendritic spine density in 3xTg- AD mice and enhances spinogenesis in vitro. We thus sought to validate that Compound 1 increases dendritic spine density in the 3xTg-AD model as expected and as suggested by both the behavioral immunohistochemical data. We performed Golgi staining and stereological quantification of dendritic spines in the stratum radiatum (sr) of hippocampal field CAI (Fig. 6 panels Al and A2). The stereological quantification indicated that 3xTg-AD mice treated with vehicle have significantly reduced dendritic spine density (Fig. 6 panels Al and A2) compared to vehicle-treated WT mice, particularly in mushroom and stubby-type spine profiles (Fig. 7). These large deficits in dendritic spines in 3xTg-AD mice (-35-50%) were reversed by treatment with Compound 1 at 3- and 30-mg/kg (Fig. 6 panels Al, A3 and A4), which increased spine density in 3xTg-AD mice to levels not statistically different from those seen in vehicle-treated WT mice. Surprisingly, the treatment with Compound 1 overcame the level of spine loss occurring before treatment began at 6 months, as well as all spine loss that occurred during the 4 weeks of treatment.

[0160] We also evaluated the effect of Compound 1 in vitro on the density of dendritic spines on primary hippocampal neurons from rat (Fig. 8; also see 14). Treatment with Compound 1 at concentrations of 0.1, 0.3, 1, 3 and 10 pM resulted in a statistically significantly increase in the mean spine density (spines/20 pm) compared to the vehicle group (37.41±5.88, 33.72±2.75, 35.65±3.68, 45.97±3.89, 24.71±2.33, respectively, vs. 12.54±1.81 in vehicle controls). Treatment with vehicle (0.1% DMSO) did not increase the mean spine density compared to an untreated control group (14.76+1.02 vs. 12.54+1.81 , respectively).

[0161] To further understand the nature of Compound 1’s synaptic rescue effects, wc measured the levels of several key synaptic proteins including, Drebrin, GluAl, p-GluAl, PSD95, synaptic vesicle glycoprotein A (SV2A), fascin, and synaptophysin, by Western Blot in hippocampal synaptosomes (Figs. 9 and 10) prepared from a subset of animals tested in behavioral assays. Changes in the levels and activity of these synaptic markers have been associated with memory impairments in AD. In accord with the observed spine deficits 3xTg-AD mice, WB analysis revealed significant decreases in the steady-state levels of Drebrin, PSD95 and the p-GluAl/GluAl ratio in 3xTg-AD vehicle mice compared to WT vehicle mice. The levels of these proteins were significantly increased with Compound 1 treatment (Figs. 9 and 10). These data suggest that the structural effects of Compound 1 on dendritic spine density are accompanied by increases in key scaffolding, actin regulatory, and glutamatergic -signaling proteins involved in the formation and plasticity of glutamatergic synapses.

[0162] The experiments show Compound 1 does not alter Af> or Tau levels in 3xTg-AD mice. Accumulation of Af> and hyperphosphorylated Tau are the hallmark features of AD molecular pathology, so any drug affecting AD progression - even if not targeting these pathways directly - may alter one or both of these characteristics. However, A|3 level was not altered by Compound 1 treatment in 3xTg-AD mice as measured by immunohistochemistry (Fig. 11) and by ELISA (Fig. 12A). Moreover, immunohistochemical and ELISA analysis revealed that neither steady-state Tau (HT7) nor phospho-Tau species recognized by ATI 80 (Thr231) were altered by Compound 1 treatment (Fig. 11 and 12B). The data suggest that the effect of Compound 1 in restoring synaptic and cognitive deficits in 3xTg-AD was not associated with any change in A and/or Tau levels.

Example 2

Homozygous transgenic TDP-43 Mice Typically Begin Dying by Day 23

[0163J This study utilized a rapidly progressing mouse model of ALS. Created by the lab of Kumar - Sing [Wils, 2010], this model, overexpresses human TDP-43 under control of a Thy- 1 promoter. In the vast majority of ALS cases, TDP-43, a predominantly nuclear mRNA binding protein, becomes mislocalized to the cytoplasm, posttranslationally modified and cleaved. It is thought that this misregulation of TDP-43, which maps to brain regions affected by ALS (and FTD), is a key driver of pathogenesis. Accordingly, mutations in TDP-43 that promote the formation of TDP-43 cytoplasmic inclusions are a cause of ALS in humans. Mice homozygous for the human TDP-43 transgene (denoted TAR4/4), develop motor symptoms, tremor and postural phenotypes within the first 2 weeks of life, which progresses rapidly leading to fatality at the beginning of the 4^th week of life, typically between postnatal days (PND) 22-25. This model is used to screen for candidate therapeutics that can have a significant impact on disease progression [Becker, 2017].

[0164] In our ongoing study at USC, homozygous TDP-43 mice were treated with Compound 1 (15 mg/kg, intraperitoneally [IP]) daily from PND 14 - a timepoint when ALS related phenotypes are already present, until they were indicated for euthanization. Significant improvements in motor functions were observed in gait (Fig. 15), posture (Fig. 16), and tremor (Fig. 17). In the scales used, wild type mice score 0 (no impairment).

[0165] All the vehicle-treated mice died by Day 24, whereas the Compound 1 treated mice survived until PND 33, 34 (Fig. 18). Thus, the therapeutic regimen regenerates lost synapses resulted in significant improvements in both motor function and survival, even though intervention was not started until after symptom onset in this very aggressive model of ALS-like pathogenesis.

Example 3

[0166] Neurons from the hippocampus of newborn rats are cultured and plated in a 24-well plate and are cultured for 14 days. At day 1, the culture medium is replaced with plain medium. At day 4, 5 nM of araC is added in order to stop glial cell mitosis and to avoid background staining, multi-dimensional plains of focus and excessive nutrient consumption. At day 14, test compound is added to the culture wells in several concentrations (1, 10, 50, and 100 nM) using DMSO as a solvent. The medium is replaced with and cells washed to remove test compound at various time points (2 minutes, 5 minutes, 10 minutes, 30 minutes, 45 minutes, 1 hours, and 2 hours). Cells are fixed on coverslips using methanol and double-stained with antibody against PSD95 for synaptic count of spines on the basal dendrites and antibody against synaptobrevin II for presynaptic imaging. DAPI staining is used for cell nuclei count. The number of spines per 20 pm length of dendrite is compared to the untreated control group. Vehicle group is treated with 0.1% DMSO.

Example 4

[0167] Ubqln2 P497S mice and wild-type (WT) mice were used in this study. The characterization of Ubqln2 P497S mice has been previously described in Le, N.T. et al, "Motor neuron disease, TDP-43 pathology, and memory deficits in mice expressing ALS-FTD-linked UBQLN2 mutations." Proceedings of the National Academy of Sciences 113.47 (2016): E7580-E7589.

[0168] Ubqln2 P497S mice and wild-type (WT) mice were divided into groups (n=9): WT vehicle, Ubqln2 vehicle, and Ubqln2 Compound 1 (10 mg/kg). Compound 1 (dissolved in 5% dimethyl sulfoxide (DMSO) and diluted with phosphate buffered saline (PBS) to 5% DMSO) was administered by intraperitoneal injection once daily for 4 weeks. Animals treated with vehicle (5% DMSO in PBS) were used as a negative control group. WT mice were used as a control group. After completion of treatment, the mice were euthanized.

[0169] The Golgi stain and dendritic spine density analysis was carried out using the same procedure as described in Example 1.

Results

[0170] The Layer 5 Motor Cortex spine density of basal and apical dendrites of the WT vehicle, Ubqln2 vehicle, and Ubqln2 Compound 1 (10 mg/kg) groups are shown in Fig. 19. The postmortem Golgi stain of dendritic spines is shown in Fig. 20. Fig. 21 and Fig. 22 show the Medial Prefrontal Cortex spine density and the Golgi stain of groups, respectively. Fig. 23 and Fig. 24 show the Field CAI Hippocampus spine density and the Golgi stain of the groups, respectively.

[0171] The in vivo experiments and imaging of the dendritic spines show that treatment of Ubqln2 P497S mice with Compound 1 at 10 mg/kg increases dendritic spine density compared to the vehicle- treated Ubqln2 control group. This study complements the findings of the 3xTg-AD mice study described in Example 1, and demonstrates the efficacy for Compound 1 to Ubqln2 mice models for ALS/FTD. [0172] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0173] The disclosures illustratively described herein may suitably be practiced in the absence of any element or elements, limitation or limitations, not specifically disclosed herein. Thus, for example, the terms “comprising”, “including,” “containing”, etc. shall be read expansively and without limitation. Additionally, the terms and expressions employed herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible.

[0174] Thus, it should be understood that although the present disclosure has been specifically disclosed by preferred embodiments and optional features, modification, improvement and variation of the disclosures embodied therein herein disclosed may be resorted to by those skilled in the art, and that such modifications, improvements and variations are considered to be within the scope of this disclosure. The materials, methods, and examples provided here are representative of preferred embodiments, are exemplary, and are not intended as limitations on the scope of the disclosure.

[0175] All publications, patent applications, patents, and other references mentioned herein are expressly incorporated by reference in their entirety, to the same extent as if each were incorporated by reference individually. In case of conflict, the present specification, including definitions, will control.

Claims

WHAT IS CLAIMED IS:

1. A method for repairing diseased neurons in a mammal afflicted with a neurodegenerative disease which method comprises: administering to said mammal a single daily dose of an effective amount of a compound of formula I:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, wherein R is hydrogen, C1-C4 alkyl, halo, hydroxyl, amino, cyano or nitro; q is from 2 to 8; and wherein said compound contacts said neurons and initiates their repair by the subsequent formation of new dendritic spines which spines form functional synapses with axons on other neurons wherein said repair is continued in the absence of the effective amount of said compound; wherein said neurodegenerative disease is characterized as early-stage or mid-stage.

2. The method of claim 1, wherein said neurodegenerative disease includes ataxia.

3. The method of claim 1, wherein said neurodegenerative disease includes cognition loss.

4. The method of claim 1, wherein said neurodegenerative disease is selected from the group consisting of Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), Parkinson’s disease, frontotemporal dementia, and Huntington’s disease.

5. The method of claim 1, wherein said neurodegenerative disease includes dementia.

6. The method of claim 5, wherein said dementia is due to AD or frontotemporal dementia.

7. The method of claim 1, wherein said mammal is a human and said effective amount is no more than 0.4 mg/kg/day.

8. The method of claim 7, wherein said effective amount is from about 0.1 to about 0.4 mg/kg/day.

The method of claim 1, wherein the neurodegenerative disease is Alzheimer’s disease.

10. The method of claim 9, wherein the Alzheimer’s disease is early-stage.

The method of claim 9, wherein the Alzheimer’s disease is mid-stage.

12. The method of claim 1, wherein the neurodegenerative disease is amyotrophic lateral sclerosis (ALS).

13. The method of claim 12, wherein the ALS is early-stage.

The method of claim 12, wherein the ALS is mid- stage.

15. The method of claim 1, wherein said compound has a serum half-life in rodents of less than about 30 minutes.

16. A unit dose for initiating formation of stable, functional synapses in a mammal suffering from decreased spine density and accordingly compromised functional synapses, said unit dose comprising no more than about 0.4 mg/kg/day of a compound of formula IA:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, q is from 2 to 8; and wherein said compound has a serum half-life of less than 3 hours, and further wherein said unit dose provides for formation of stable functional synapses in said mammal.

17. The unit dose of claim 1, wherein said unit dose comprises from about 0.1 mg/kg/day to about 0.4 mg/kg/day.

18. The unit dose of claim 1, wherein said decreased functional spine density is the result of a neurological condition.

19. The unit dose of claim 1, wherein said unit dose is prescribed for administration once a day.

20. A method for generating functional spines on a neuron which method comprises transiently contacting said neuron with an effective amount of a compound of formula I:

or a pharmaceutically acceptable salt, an isotopically enriched analog, a tautomer, a prodrug, a stereoisomer, or a mixture of stereoisomers thereof, wherein R is hydrogen, C1-C4 alkyl, halo, hydroxyl, amino, cyano or nitro; q is from 2 to 8; and wherein said transient contact initiates spinogenic activity that leads to formation of new functional spines; and wherein said transient contact of an effective amount terminates after initiation and before complete maturation of said functional spines.