U.S. patent application number 13/614283 was filed with the patent office on 2013-01-10 for methods of treating fragile x syndrome.
This patent application is currently assigned to Seaside Therapeutics, Inc.. Invention is credited to Mark F. Bear, Randall L. Carpenter, Kathryn Roberts.
Application Number | 20130012586 13/614283 |
Document ID | / |
Family ID | 39272866 |
Filed Date | 2013-01-10 |
United States Patent
Application |
20130012586 |
Kind Code |
A1 |
Roberts; Kathryn ; et
al. |
January 10, 2013 |
Methods of Treating Fragile X Syndrome
Abstract
Subjects having fragile X syndrome are treated with a
composition that includes gamma-aminobutyric acid agonists. The
gamma-aminobutyric acid agonist (GABA) can be a GABA(B) agonist,
such as baclofen, including racemic and R-baclofen.
Inventors: |
Roberts; Kathryn;
(Fairfield, CT) ; Carpenter; Randall L.; (Boston,
MA) ; Bear; Mark F.; (Boston, MA) |
Assignee: |
Seaside Therapeutics, Inc.
Cambridge
MA
|
Family ID: |
39272866 |
Appl. No.: |
13/614283 |
Filed: |
September 13, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13362656 |
Jan 31, 2012 |
8273715 |
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13614283 |
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12454202 |
May 14, 2009 |
8143311 |
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13362656 |
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PCT/US2007/024311 |
Nov 21, 2007 |
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12454202 |
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61001567 |
Nov 2, 2007 |
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60860733 |
Nov 22, 2006 |
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Current U.S.
Class: |
514/567 |
Current CPC
Class: |
A61K 31/428 20130101;
A61P 25/00 20180101; A61P 25/22 20180101; A61P 25/08 20180101; A61P
25/18 20180101; A61K 31/197 20130101; A61K 31/195 20130101; A61K
31/215 20130101; A61K 31/215 20130101; A61P 43/00 20180101; A61P
15/00 20180101; A61K 2300/00 20130101; A61K 2300/00 20130101; A61K
31/195 20130101; A61K 31/428 20130101; A61K 2300/00 20130101 |
Class at
Publication: |
514/567 |
International
Class: |
A61K 31/197 20060101
A61K031/197; A61P 25/00 20060101 A61P025/00 |
Claims
1. A method of improving at least one of motivation, calmness,
class participation, ability to tolerate stress and sleep patterns
in a human having fragile X syndrome, comprising the step of orally
administering to the human a composition that includes a
therapeutically effective amount of at least one GABA(B)
agonist.
2. The method of claim 1, wherein the GABA(B) agonist is
administered to the human in a dose of about 0.001 mg/kg/day to
about 5 mg/kg/day.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 13/362,656, filed Jan. 31, 2012, which is a continuation of
U.S. application Ser. No. 12/454,202, filed May 14, 2009 (now U.S.
Pat. No. 8,143,311), which is a continuation of International
Application No. PCT/US2007/024311, filed Nov. 21, 2007, which
designates the U.S., published in English, and claims the benefit
of U.S. Provisional Application No. 61/001,567, filed Nov. 2, 2007
and U.S. Provisional Application No. 60/860,733, filed Nov. 22,
2006. The entire teachings of the above applications are
incorporated herein by reference.
INCORPORATION BY REFERENCE OF MATERIAL IN ASCII TEXT FILE
[0002] This application incorporates by reference the Sequence
Listing contained in the following ASCII text file being submitted
concurrently herewith:
[0003] a) File name: 39331008013 SequenceListing.txt; created Sep.
12, 2012, 1 KB in size.
BACKGROUND OF THE INVENTION
[0004] Mental retardation, Down's syndrome, fragile X syndrome and
autism are developmental and genetic disorders that affect day to
day functioning, including learning, memory, speech, social skills
and behavior. Currently available treatment regimens for humans
with mental retardation, Down's syndrome, fragile X syndrome and to
assist in day-to-day functioning, include, for example, behavioral
modifications and treatment with a range of medications including
anti-depressant and anti-psychotic drugs. However, such regimens
frequently are not effective or may produce undesirable
side-effects with long term use, particularly the use of
anti-psychotic drugs. Thus, there is a need to develop new,
improved and effective methods to treat mental retardation, Down's
syndrome, fragile X syndrome and autism.
SUMMARY OF THE INVENTION
[0005] The present invention relates to a method of treating humans
having mental retardation, Down's syndrome, fragile X syndrome and
autism.
[0006] In one embodiment, the invention is a method of treating a
human, comprising the step of administering to a human having at
least one condition selected from the group consisting of Down's
syndrome, fragile X syndrome and autism a composition that includes
a gamma-aminobutyric acid agonist.
[0007] In another embodiment, the invention is a method of treating
a human, comprising the step of administering to a human having at
least one condition selected from the group consisting of Down's
Syndrome, fragile X syndrome and autism a composition that includes
Formula I:
##STR00001##
[0008] In yet another embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes baclofen, wherein the baclofen is
administered to the human at a dose of about 2 mg per day for days
1, 2 and 3 of treatment, a dose of about 4 mg per day for days 4, 5
and 6 of treatment, a dose of about 6 mg per day for days 7, 8 and
9 of treatment, a dose of about 10 mg per day for days 10, 11 and
12 of treatment, a dose of about 20 mg per day for days 13, 14 and
15 of treatment, a dose of about 30 mg per day for days 16, 17 and
18 of treatment and a dose between about 30 mg to about 80 mg per
day for the duration of the treatment.
[0009] In an additional embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes baclofen, wherein the baclofen is
administered to the human at a dose of about 15 mg for days 1, 2
and 3 of treatment, a dose of about 30 mg for days 4, 5 and 6 of
treatment, a dose of about 45 mg for days 7, 8 and 9 of treatment,
a dose of about 60 mg for days 10, 11 and 12 of treatment and a
dose between about 60 mg to about 80 mg per day for the duration of
the treatment.
[0010] In still another embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes at least about 51 mole percent
S-baclofen relative to the total S-baclofen and R-baclofen in the
composition administered to the human.
[0011] In a further embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes at least about 51 mole percent
R-baclofen relative to the total R-baclofen and S-baclofen in the
composition administered to the human.
[0012] An additional embodiment of the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes baclofen, wherein the baclofen is
administered to the human at a dosing regimen of at least one
member selected from the group consisting of about 1 mg twice a
day, about 2 mg twice a day, about 3 mg twice a day, about 5 mg
twice a day, about 10 mg twice a day and about 10 mg three times a
day.
[0013] In yet another embodiment, the invention is a method of
treating a subject, comprising the step of administering to a
subject having at least one condition selected from the group
consisting of mental retardation, Down's syndrome, fragile X
syndrome and autism a composition that includes at least one M1
muscarinic antagonist.
[0014] Advantages of the claimed invention can include, for
example, treatment of mental retardation, Down's syndrome, fragile
X syndrome and autism in a manner that can improve symptoms (e.g.,
reduce anxiety and irritability; increase cognitive function,
communication and/or social interaction), efficacy or reduce side
effects and thereby improve tolerability for use over a relatively
long period of time without significant side effects. The methods
of the invention can provide an effective manner to treat a subject
having mental retardation, Down's syndrome, fragile X syndrome
and/or autism.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 depicts the effects of racemic baclofen on the
inhibition of marble-burying behavior in fragile X (Fmr1) knock out
(KO) mice (n=7-8 mice/group). Data are expressed as the mean.+-.SEM
number of marbles buried.
[0016] FIG. 2 depicts the effects of R(+)-baclofen on
marble-burying behavior in Fmr1 KO mice (n=10-16 mice/group). Data
are expressed as the mean marbles buried.+-.SEM. An asterik (*)
indicates data for the 10 mg/kg dose was significantly less
(p<0.05) than all other groups.
[0017] FIG. 3 depicts the effects S(-)-baclofen on marble-burying
behavior of Fmr1 KO mice (n=11-15 mice/group). Data are expressed
as the mean number of marbles buried.+-.SEM. The # symbol indicates
that the data for the 1 mg/kg dose was significantly greater than
the 0 mg/kg dose. The asterik (*) indicates that the 50 mg/kg dose
was significantly different (p<0.05) than all other groups.
[0018] FIG. 4 depicts the effect of R(+)-baclofen and S(-)-baclofen
on audiogenic seizures in Fmr1 KO mice (n=9-10 mice/group). Data
are expressed as a percentage of mice treated with vehicle (0
mg/kg), R(+)- or S(-)-baclofen, that exhibited audiogenic
seizures.
[0019] FIG. 5 depicts the effect of R(+)- and S(-)-baclofen on
open-field activity of Fmr1 KO male mice. Data are expressed as the
mean.+-.SEM of the total distance traveled. The symbol # indicates
that the data for the vehicle treated Fmr1 KO mice are
significantly higher than wild type (WT) mice. An asterik (*)
indicates that the vehicle-treated Fmr1 KO mice were significantly
higher than the respective dose of R(+)- or (S-)-baclofen.
[0020] FIG. 6 depicts dicyclomine inhibition of marble-burying
behavior in fragile X knockout (KO) mice (n=3-5 mice/group). Data
are expressed as the mean number of marbles buried.+-.SEM.
[0021] FIG. 7 depicts audiogenic seizures in young Fmr1 KO mice
with or without dicyclomine (diccyc.) treatment. Data are the
percentage of mice treated with vehicle (0 mg/kg) or dicyclomine
(40 mg/kg) that displayed audiogenic seizures.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The features and other details of the invention, either as
steps of the invention or as combinations of parts of the
invention, will now be more particularly described and pointed out
in the claims. It will be understood that the particular
embodiments of the invention are shown by way of illustration and
not as limitations of the invention. The principle features of this
invention can be employed in various embodiments without departing
from the scope of the invention.
[0023] In one embodiment, the invention is a method of treating a
human, comprising the step of administering to a human having at
least one condition selected from the group consisting of Down's
syndrome, fragile X syndrome and autism a composition that includes
a gamma-aminobutyric acid (GABA) agonist, such as a GABA(B)
receptor agonist (also referred to herein as "GABA(B) agonist" or
"GABAB agonist").
[0024] GABA (gamma-amino butyric acid) is an abundant
neurotransmitter in the mammalian brain. GABA, like other
neurotransmitters, including L-glutamate, serotonin and
acetylcholine, activates ionotropic and metabotropic receptors.
Ionotropic receptors are ligand gated ion channels that convey fast
synaptic transmission, whereas G-protein coupled metabotropic
receptors modulate synaptic transmission through intracellular
effector systems. GABA exerts its effects through ionotropic
ligand-gated GABA(A) (also referred to as "GABAA"), GABA(C) (also
referred to as "GABAC") and GABA(B) (also referred to as "GABAB")
receptors to produce slow, and prolonged synaptic inhibitory
signals by activating a Cl-conductance that can be allosterically
modulated by psychoactive drugs, such as the benzodiazepines,
barbiturates and neurosteroids.
[0025] The subunits of the GABA(A) receptor have sequence homology
with the nAChR subunit family. A family of GABA(A) receptors
subtypes exists, which are generated by alternative splicing of
alpha 1-6, beta 1-4, gamma 1-4, delta, epsilon, pie, theta, and
rho1-3 to form protein complexes. Various GABA(A) subunits show
distinct patterns of temporal and spatial expression that may have
tissue specific physiological roles. GABA(A) receptor proteins are
characterized by the presence of a cleavable signal peptide, a
large extracellular N-terminus, three transmembrane domains, a
large cytoplasmic domain followed by another transmembrane domain
and C-terminal extracellular domain. The other common motif is
referred to as a Cys-loop and two Cys loops are separated by
thirteen amino acids in the extracellular domain of the receptor.
The regions between the third and fourth transmembrane domain and
the large cytoplasmic loop are least conserved among various GAA
subunits, which may confer subunit specific functionality. GAA
genes are distributed as clusters throughout the human genome
(chromosomes 4, 5, 15, and X; delta subunit on chromosome 1).
[0026] GABA(B) receptors are metabotropic transmembrane receptors
for gamma-aminobutyric acid (GABA) that are linked by G-proteins to
potassium channels (Chen K, et al., Brain Res Bull 67: 310-8
(2005)). GABA(B) receptors are found in the central and peripheral
autonomic nervous system. GABA(B) receptors can stimulate potassium
channels, which can result in hyperpolarization of the neuron,
prevent sodium channel influx and, thus, neurotransmitter release.
GABA(B) receptors may also reduce adenylyl cyclase activity and
decrease calcium conductance in a neuron.
[0027] GABA(B) receptors are structurally similar to metabotropic
glutamate receptors and are divided into two subtypes GABA(B)1 and
GABA(B).sub.2, which appear to assemble as heterodimers in neuronal
membranes by linking by carboxy-termini.
[0028] An "agonist," as used herein, is a compound that activates
cell signaling. For example, a GABA(B) receptor agonist activates
cell signaling mediated through GABA(B) receptors and an
.alpha.2-adrenergic agonist activates cell signaling mediated
through .alpha.2-adrenergic receptors.
[0029] The GABA agonists employed in the methods of the invention
preferably cross the blood brain barrier. The GABA agonists for use
in the methods described herein can inhibit glutamate release in
the central nervous system, such as in the cortex and basal ganglia
of the central nervous system.
[0030] In another embodiment, the invention is a method of treating
a human, comprising the step of administering to a human having at
least one condition selected from the group consisting of mental
retardation, Down's Syndrome, fragile X syndrome and autism a
composition that includes Formula I:
##STR00002##
[0031] Formula I is baclofen, which is also referred to as
.beta.-(Aminomethyl)-4-chlorobenzenepropanoic acid;
.beta.-(aminomethyl)-p-chlorohydrocinnamic acid;
.gamma.-amino-.beta.-(p-chlorophenyl)butyric acid;
.beta.-(4-chlorophenyl)GABA. Baclofen is also referred to as
Baclon, Lioresal, Kemstro and Myospan.
[0032] The methods of the invention can include the use of a
GABA(B) receptor agonist in combination with, for example, Formula
II:
##STR00003##
[0033] Formula II is 2-amino-6-trifluormethoxybenzothiazole and is
also referred to herein as "riluzole" (see, for example, U.S. Pat.
No. 4,370,338, the teachings of which are hereby incorporated by
reference in its entirety).
[0034] Formula II is FDA approved for the treatment of amyotrophic
lateral sclerosis. It has multiple activities, including inhibition
of presynaptic glutamate release by inactivation of P/Q-type
calcium channels, enhancement of glutamate uptake in astrocytes,
and inhibition of voltage-dependent sodium channels in mammalian
CNS neurons. It has also been reported to potentiate AMPA/KA
receptor-mediated transmission, as well as enhance brain-derived
neurotrophic factor. Riluzole has been shown to have
neuroprotective, anticonvulsant activity, anti-anxiety activity,
and antidepressant activity in animal models and in humans.
[0035] The subject can be treated with salts (e.g., acid salts,
base salts, HCl, oxaylate, calcium, sodium, magnesium, lithium),
prodrugs, polymorphs and other structural and functional
derivatives thereof of the compounds, such as Formulas I and II,
described herein.
[0036] Mental retardation means that a subject has lower than
average intelligence. Intelligence describes a subject's ability to
think, learn and solve problems. A subject with mental retardation
may have difficulty learning, may take longer to learn social
skills, such as how to communicate, and may be less able to care
for himself or herself and to live on his or her own as an
adult.
[0037] Down's syndrome is a disorder that includes a combination of
birth defects, including some degree of mental retardation,
characteristic facial features and, often, heart defects, increased
infections, problems with vision and hearing, and other health
problems. The severity of these problems varies greatly among
affected subjects. Down's syndrome is generally is caused by an
extra copy chromosome 21 and is also referred to as trisomy 21.
[0038] The fragile X syndrome, as implied by its name, is
associated with a fragile site expressed as an isochromatid gap in
the metaphase chromosome at map position Xq 27.3. Fragile X
syndrome is a genetic disorder caused by a mutation in the
5'-untranslated region of the fragile X mental retardation 1 (FMR1)
gene, located on the X chromosome. The mutation that causes fragile
X syndrome is a associated with a CGG repeat in the fragile X
mental retardation gene FMR-1. When a subject has more than about
200 CGG repeats, the fragile X gene is hypermethylated, silenced,
fragile X mental retardation protein (FMRP) is not produced and the
subject is diagnosed as having fragile X syndrome (See, for
example, U.S. Pat. Nos. 6,107,025 and 6,180,337, the entire
teachings of both of which are hereby incorporated by reference in
their entirety).
[0039] The fragile X syndrome segregates as an X-linked dominant
disorder with reduced penetrance. Either sex when carrying the
fragile X mutation may exhibit mental deficiency, which is variable
in severity.
[0040] Children and adults with fragile X syndrome have varying
degrees of mental retardation or learning disabilities and
behavioral and emotional problems, including autistic-like features
and tendencies. Young children with fragile X syndrome often have
delays in developmental milestones, such as learning how to sit,
walk and talk. Affected children may have frequent tantrums,
difficulties in paying attention, frequent seizures (e.g., temporal
lobe seizures) are often highly anxious, easily overwhelmed, can
have sensory hyperarousal disorder, gastrointestinal disorders, may
have speech problems and unusual behaviors, such as hand flapping
and hand biting.
[0041] Fragile X syndrome can be diagnosed by an established
genetic test performed on a sample (e.g., blood sample, buccal
sample) from the subject. The test determines whether a mutation or
pre-mutation is present in the FMR-1 gene of the subject.
[0042] Subjects with fragile X syndrome can also have autism,
attention deficient disorder and/or obsessive compulsive disorder.
Fragile X syndrome is a prevalent form of inherited mental
retardation and is characterized by developmental delay,
hyperactivity, attention deficit disorder and autistic-like
behaviors (Jin, P., et al., Hum Mol Genet. 9: 901-908 (2000)).
[0043] About 5% of all children diagnosed with autism have a
mutation in the FMR1 gene and also have fragile X syndrome (FXS).
About 15 to about 20% of subjects with fragile X syndrome meet the
full diagnostic criteria for autism. Although mental retardation is
a hallmark feature of fragile X syndrome, subjects with fragile X
syndrome often display autistic features ranging from shyness, poor
eye contact, and social anxiety in mild cases to hand flapping,
hand biting and perseverative speech in the severely affected.
Subjects with fragile X syndrome display other symptoms associated
with autism such as attention deficit and hyperactivity, seizures,
hypersensitivity to sensory stimuli obsessive-compulsive behavior
and altered gastrointestinal function. The FMR1 mutation prevents
expression of a single protein (FMRP). Brain development in the
absence of FMRP gives rise to the major symptoms of fragile X
syndrome. A key tool allowing for a better understanding of the
function of FMRP has been development of the Fmr1 knockout
mouse.
[0044] In addition to core symptoms, children with fragile X
syndrome frequently have serious behavioral disturbances such as
irritability, aggression and self-injurious behaviors. In a recent
study of males with fragile X syndrome (ages 8-24), self-injurious
behavior was reported in 79%, and aggressive behavior in 75%, of
subjects during a two month observation period (Hessl, D., et al.,
The National Fragile X Foundation Quarterly, Issue 25:10-13
(2006)). Despite the common occurrence of irritable, aggressive and
self-injurious behavior in subjects with fragile X syndrome, there
has been little research assessing treatments for these
symptoms.
[0045] Although there has been little research in subjects with
fragile X syndrome, serious behavioral disturbances such as
self-injurious behavior, aggression and tantrums occur frequently
in individuals with autism (McCracken, J. T., et al., N. Engl. J.
Med. 347:314-321 (2002)), and there have been numerous clinical
trials assessing a variety of therapeutic treatments. Behavior
therapy may provide benefits, but is highly individualized and has
not been evaluated in randomized clinical trials (Schreibman, L.,
J. Autism Dev. Discord. 5:373-378 (2002)). Similarly, treatments
with several medications in various chemical classes have had
limited success (McDougle, C. J., et al., Child Adolesc. Psychiatr.
Clin. N. Am. 9:201-224 (2002)). Risperidone, an atypical
antipsychotic, has been used to treat behaviors in subjects with
autism (McCracken, J. T., et al., N. Engl. J. Med. 347:314-321
(2002)). However, risperidone produces a number of undesirable side
effects including increased appetite (73%) and weight gain (2.7 kg
over 8 weeks), fatigue (59%), drowsiness (49%), drooling (27%), and
dizziness (16%) (McCracken, J. T., et al., N. Engl. J. Med.
347:314-321 (2002)). There are also unresolved safety concerns that
long-term therapy may cause extrapyramidal symptoms and that
elevated prolactin levels may affect growth and sexual maturation.
These side effects limit tolerability and usefulness of risperidone
alone for treating irritable aberrant behavior in subjects with
autism.
[0046] Formal studies have not been published in subjects with
fragile X syndrome, however clinical experience with atypical
antipsychotics, such as risperidone alone is consistent with the
results observed in subjects with autism (McCracken, J. T., et al.,
N. Engl. J. Med. 347:314-321 (2002); Berry-Kravis, E., et al.,
Ment. Retard. Devel Disabil. Res. Rev. 10:42-48 (2004)).
Specifically, risperidone alone reduces irritable behavior, but the
side effect profile limits use of it alone in subjects with fragile
X syndrome.
[0047] Initial studies of the behavioral phenotype of the Fmr1 KO
mouse on a mixed genetic background reported that the Fmr1 KO mice
displayed increased exploratory and locomotor activity compared to
wild-type controls, and also a slight learning impairment in the
Morris water maze (Bakker, C. E., et al., Cell 78:23-33 (1994)).
This learning impairment has been further analyzed by several
groups using the Morris water task, plus-shaped water maze, operant
conditioning paradigms, conditioned fear, passive avoidance and the
radial maze (Bakker, C. E., et al., Cell 78:23-22 (1994). Fmr1 KO
mice have impaired learning processes when assessed on assays that
had previously not been attempted. Fmr1 KO mice do have impaired
learning that is clearly task dependent. It is likely that learning
and memory performance of Fmr1 KO mice is dependent on genetic
background (Paradee, W., et al., Neuroscience 94:185-192 (1999)).
Although the learning and memory phenotype of the Fmr1 KO mouse has
been challenging and somewhat elusive, there are sufficient data
indicating that Fmr1 KO mice are hyperactive, have altered
responses on tests of anxiety, and altered sensorimotor gating
(Mineur, Y. S., et al., Hippocampers 12:39-46 (2002)). FMRP can
regulate behavioral states of activity/arousal, anxiety-related
responses, and social interactions (Bakker, C. E., et al., Cell
78:23-33 (1994); Peier, A. M., et al., Hum. Mol. Genet. 9:1145-1159
(2000)).
[0048] By challenging the Fmr1 KO mice with different test
situations, the KO mice are hyperactive, can display increased
anxiety-like responses, do show abnormal social interactions, and
have poor learning and memory. Fmr1 KO mice display several
abnormal behavioral responses that parallel symptoms of FXS.
Behavioral responses of Fmr1 KO mice depend on genetic background.
Fmr1 KO mice on particular genetic backgrounds display increased
`autistic-like` traits. Specifically, Fmr1 KO mice on a C57BL/6J X
DBA/2 F1 (D2-Fmr1 F1) hybrid background display increased
stereotypies in the open-field, increased obsessive-like responding
in the marble-burying task, and have reduced social interactions,
while Fmr1 KO mice on a C57BL/6J X 129S1/SvImJ F1 (129-Fmr1 F1)
hybrid background appear to have poor social recognition. That only
some of the Fmr1 KO strains display increased `autistic-like`
traits is consistent with the observations that only 15-20% of FXS
individuals have autism, and may have variation in FXS due to
genetic background. Other mouse models of FXS can display unique
autistic-like features. (Spencer, C. M., et al., Genes, Brain and
Behavior, 4:420-430 (2005)).
[0049] Cognitive behavioral therapy has been used to improve
language and socialization in fragile X syndrome and autism. In
addition, many classes of psychiatric drugs are used in clinical
practice to treat symptoms and behavior in both populations
(Berry-Kravis, E. et al., Ment. Retard. Devel Disabil. Res. Rev.
10:42-48 (2004); Malone, R. P., et al., CNS Drugs 19:923-924
(2005)). In recent years, pharmacological treatment with the
atypical antipsychotic risperidone has been commonly employed to
augment non-pharmacological approaches in the treatment of
individuals with autism. A randomized placebo-controlled trial of
risperidone in autistic children demonstrated significant
improvement on the irritability subscale of the Aberrant Behavior
Checklist and the Clinical Global Impressions-Improvement
(McCracken, J. T., et al., N. Engl. J. Med. 347:314-321 (2002)).
However, adverse events included weight gain, increased appetite,
fatigue, drowsiness, dizziness, and drooling. Social isolation and
communication were not improved by administration of risperidone
and adverse side effects such as extrapyramidal symptoms and
dyskinesias have been associated with risperidone use in autistic
children (Malone, R. P., et al., J. Am. Acad. Child Adolsecent.
Psychiatry 41:140-147 (2002)).
[0050] Although a number of other drugs, including antipsychotics,
antidepressants, and anticonvulsants have mixed results in treating
various symptoms and behaviors associated with autism and fragile x
syndrome; there is a need to develop new treatments.
[0051] As described herein, R-baclofen may be more potent than
S-baclofen for reducing obsessive-compulsive and repetitive
behavior, and for reducing audiogenic seizures, with minimal side
effects. R-baclofen may be useful for the management of typical
problem behavior, such as irritability and aggression, in humans
with fragile X syndrome. Baclofen may improve irritable aberrant
behavior and also have an improved safety and tolerability profile
over atypical antipsychotics in the treatment of fragile X syndrome
and/or autism. Baclofen may be used in combination with other
medications, such as risperidone, antipsychotics, Group I mGluR
antagonists and M1 muscarinic receptor antagonists.
[0052] The pharmacokinetics of baclofen and muscarinic M1
antagonists, such as dicylomine, in mice to define systemic
exposure can be assessed.
[0053] Marble burying behavior in rats is considered to be a model
of obsessive-compulsive disorder (OCD) in humans (Matushita, M., et
al., Med. Bull. Fukuoka Univ. 32:159-165 (2005)). Data described
herein show that baclofen inhibits marble-burying behavior.
[0054] Subjects with autism can have several symptoms that can
range from mild to severe. Such symptoms can include difficulties
interacting with others; making friends; communication problems,
both with spoken language and nonverbal gestures; insistence on
sameness; and some degree of mental retardation or learning
disabilities in most, but not all, of affected children. Subjects
with a mild autistic spectrum disorder, referred to as Asperger
syndrome, can share some of the features of autism, have normal
intelligence and can learn to speak at the expected age. Autism is
generally diagnosed by observing the behavior of the child and
screening tests that assess a number of characteristics and
behaviors associated with autism. Subjects with autism can also
have, for example, obsessive compulsive behaviors, sleep disorders
and/or gastrointestinal disorders.
[0055] A broad range of psychiatric drugs are used to treat
symptoms and improve behavior in subjects with autism.
Antipsychotics are commonly used to treat moderate to severe
behavioral problems associated with autism. Risperidone, an
atypical antipsychotic that is used to treat aggression,
hyperactivity, and other disorders associated with autistic
behavior and aberrant behaviors in fragile X syndrome, can be used
in combination with the GABA agonists, M1 muscarinic receptor
antagonists and Group I mGluR antagonists in the methods described
herein. Antagonism of the 5-HT.sub.2A and D.sub.2 receptors is
considered to be crucial for efficacy of the atypical
antipsychotics in schizophrenia, with higher occupancy of the
5-HT.sub.2A receptor versus D.sub.2 being the key to decreased
movement side effects. Although all of the atypical antipsychotics
share these two pharmacological actions, they differ by having
varying activity at other serotonin and dopamine receptors.
[0056] Perospirone, an atypical antipsychotic drug approved in
Japan for treatment of schizophrenia, has pharmacologic properties
that are different from risperidone, and may be useful in the
treatment of autism, mental retardation and fragile X syndrome.
Perospirone's active metabolite, hydroxyperospirone, has a
pharmacologic profile that may be useful to treat anxiety and
obsessive-compulsive behavior. For example, hydroxyperospirone
achieves relatively high plasma concentrations that are acceptable
safety and tolerability levels in humans, and may make a
significant contribution to the efficacy observed during treatment
with perospirone.
[0057] Recent characterization of mutant mice that model human
genetic disease and display `autistic-like` traits provides an
opportunity to evaluate pharmacologic interventions on genetically
induced and well characterized `autistic-like` behaviors.
[0058] Autism is a disorder characterized by impairments in social
interaction and communication, as well as restricted, repetitive
and stereotyped patterns of behavior, interests and activities
(DSM-IV). The etiology of autism can be medically diagnosed for a
less than 10% of individuals and for many of these the diagnosis is
attributable to single-gene deficits such as fragile X syndrome,
neurofibromatosis or tuberous sclerosis. There is considerable
evidence that the remaining cases of "idiopathic" autism represent
a largely heritable disorder. Twin studies and data from
whole-genome screens suggest that interactions between at least 10
genes predispose to development of autism. Furthermore, it appears
that epigenetic and environmental factors contribute to variable
expression in those genetically predisposed. The complex
interaction of genetic and non-genetic factors in the etiology of
"idiopathic" autism has hindered development of representative
animal models and development of new pharmaceutical treatments.
[0059] In contrast to the complexity of "idiopathic" autism, a
number of human monogenic syndromes have a high incidence of
autism. Animal models for a number of these human monogenic
syndromes are available. These animal models of single gene defects
are providing new insights for potential pharmaceutical treatments
for diseases such as neurofibromatosis and fragile X syndrome.
Fragile X syndrome (Fmr1) knockout mice, which model the single
gene defect in the human fragile X syndrome, are used. Some of
these mice, as well as some humans with fragile X syndrome, have
autistic behaviors.
[0060] The methods of the invention can be employed to treat
additional conditions that can be associated with autism or fragile
X syndrome, for example, Coffin-Lowry syndrome, Cohen syndrome,
Duchenne/Becker muscular dystrophies, Neurofibromatosis, Joubert
syndrome, Lujan-Fryns syndrome, PTEN mutations, Noonan syndrome,
Orstavik syndrome, ARX mutations, CHARGE, Angelman syndrome,
Nance-Horan syndrome, Prader-Willi syndrome, Cerebral dysgenesis
and Smith-Lemli-Optiz syndrome.
[0061] The methods of the invention can be employed to treat
pervasive developmental disorders with no identified source and
autism and other disorders of brain development.
[0062] The methods of the invention can also be employed to treat
disorders of brain development including Autism Spectrum Disorders
(Pervasive Developmental Disorders), Rett's syndrome, Childhood
Disintegrative Disorder, Asperger syndrome and Tuberous
Sclerosis.
[0063] The methods of the invention can be employed to treat
deficits/symptoms, for example, deficits in learning, memory,
executive function, attention and/or processing speed. Such
deficits can be deficits associated with or observed in subjects
with mental retardation, fragile X syndrome, Down's syndrome and
autism; and pervasive developmental disorders, including pervasive
developmental disorders with no obvious source.
[0064] The methods of the invention can be employed to treat
neuropsychiatric disorders and anxiety disorders, including anxiety
disorders that are associated with or observed in subjects that
have mental retardation, autism, Down's syndrome and fragile X
syndrome. Such anxiety disorders include, for example, specific
phobias, such as phobias of the doctor and dentist; agoraphobia and
separation anxiety. Such disorders can also include, for example,
bipolar disorders, repetitive and stereotyped behavior, obsessive
and compulsive traits/disorders, aggressive behavior,
schizophrenia, hyperactivity, pain, itching, sensory hyperarousal,
seizures, behavioral problems, sleep disorders (including insomnia,
hypersomnia and abnormal behaviors during sleep).
[0065] The methods of the invention can also be employed to treat
gastrointestinal disorders and metabolic disorders in subjects with
mental retardation, fragile X syndrome, Down's syndrome and autism.
Autistic behavior (deficits in social interaction, verbal and
non-verbal communication, and restricted/repetitive behaviors or
interests) in subjects with autism, mental retardation, fragile X
syndrome and Down's syndrome can also be treated by the methods of
the invention.
[0066] The human administered the GABA agonist, in particular a
GABA(B) agonist (e.g., baclofen), can further be administered
(e.g., before, concomitantly, sequentially or after) at least one
member selected from the group consisting of an antidepressant, a
.alpha.2-adrenergic agonist, an anticonvulsant, a nicotinic
receptor agonist, an endocannabinoid receptor agonist, an
anticonvulsant, and anti-psychotic, an AMPA agonist, a M1
muscarinic antagonist and a Group I mGluR antagonist. The methods
of the invention can be employed to treat fragile X-associated
tremor/ataxia syndrome (FXTAS) and movement disorders. As discussed
above, an excess of about 200 CGG repeats in the 5'-untranslated
region of the FMR1 gene results in transcriptional silencing of the
FMR1 gene and fragile X syndrome. Subjects with premutation
expansions (about 55 to about 200 CGG repeats in the FMR1 gene) are
generally unaffected intellectually and may develop FXTAS, which is
characterized by progressive cerebellar ataxia, parkinsonism,
dementia and autonomic dysfunction (Baba, Y., et al., Current
Opinion in Neurology 18:393-398 (2005), the teachings of which are
hereby incorporated by reference in its entirety).
[0067] One of skill in the art would be able to employ
well-established criteria to diagnosis a subject that has mental
retardation, Down's syndrome, fragile X syndrome and autism and the
conditions or deficits described herein. (See, for example,
Patzold, L. M., et al., J. Paediatr. Child Health, 34:528-533
(1998); Malow, B. A., Ment. Retard Dev. Disabil. Res. Rev.
10:122-125 (2004); Robinson, A. M., et al., Child Care Health Dev.
30:139-150 (2004); Couturier, J. L., et al., J. Am. Acad Child
Adolesc Psychiatry 44:815-822 (2005); Kuddo, T., et al., Curr.
Opin. Pediatr. 15:339-343 (2003); Molloy, C. A., et al., Autism
7:165-171 (2003)).
[0068] Humans with fragile X syndrome treated by the methods
described herein can also have autism.
[0069] In an additional embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes baclofen, wherein the baclofen is
administered to the human at a dose of about 15 mg for days 1, 2
and 3 of treatment, a dose of about 30 mg for days 4, 5 and 6 of
treatment, a dose of about 45 mg for days 7, 8 and 9 of treatment,
a dose of about 60 mg for days 10, 11 and 12 of treatment and a
dose between about 60 mg to about 80 mg per day for the duration of
the treatment.
[0070] In yet another embodiment, the invention is a method of
treating a human, comprising administering to a human having at
least one condition selected from the group consisting of mental
retardation, Down's syndrome, fragile X syndrome and autism a
composition that includes at least about 51 mole percent S-baclofen
relative to the total S-baclofen and R-baclofen in the composition
administered to the human.
[0071] In a further embodiment, the invention is a method of
treating a human, comprising administering to a human having at
least one condition selected from the group consisting of mental
retardation, Down's syndrome, fragile X syndrome and autism a
composition that includes at least about 51 mole percent R-baclofen
relative to the total R-baclofen and S-baclofen in the composition
administered to the human.
[0072] The subject treatment by the methods of the invention
described herein can be a rodent (e.g., mouse, rat) or a primate
(e.g., a monkey, baboon, human). In a particular embodiment, the
subject is a human.
[0073] In yet another embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
fragile X syndrome and autism a composition that includes
R-baclofen (e.g., at least about 99 mole percent, about 95 mole
percent, about 90 mole percent, about 85 mole percent, about 80
mole percent, about 75 mole percent, about 70 mole percent, about
65 mole percent, about 60 mole percent, about 55 mole percent or
about 51 mole percent R-baclofen relative to the total R-baclofen
and S-baclofen in the composition administered to the human).
[0074] In an additional embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
fragile X syndrome and autism a composition that includes
S-baclofen (e.g., at least about 99 mole percent, about 95 mole
percent, about 90 mole percent, about 85 mole percent, about 80
mole percent, about 75 mole percent, about 70 mole percent, about
65 mole percent, about 60 mole percent, about 55 mole percent, or
about 51 mole percent S-baclofen relative to the total S-baclofen
and R-baclofen in the composition administered to the human).
[0075] The compounds employed in the methods of the invention can
be administered to a subject with (e.g., before, concomitantly,
sequentially or after) administration of other compounds that are
employed to treat a particular disorder or condition in the
subject. For example, the compositions of the invention can be
administered with at least one member selected from the group
consisting of a Group II mGluR agonist, Group II mGluR agonist,
GSK3.beta. antagonists, NAAG peptidase inhibitors, Group I mGluR
antagonist, an antidepressant, an anti-psychotic, an
.alpha.2-adrenergic agonist, an anticonvulsant, a nicotinic
receptor agonist, an endocannabinoid receptor antagonist, a M1
muscarinic receptor antagonist, and an AMPA agonist.
[0076] Glycogen synthase kinase-3 (GSK3) is an enzyme with a
diverse number of actions in intracellular signaling systems,
regulating neuronal plasticity, gene expression and cell survival.
GSK3.beta. is known to participate in many signaling pathways and
cellular activities. GSK3.beta. is a key element of the signaling
pathway whereby Group I mGluR signaling regulates dendritic
synaptic protein synthesis.
[0077] N-Acetyl-1-aspartyl-1-glutamate (NAAG) is one of the three
most prevalent neurotransmitters in the mammalian brain. NAAG acts
as an agonist at Group II metabotropic glutamate (e.g., mGluR2,
mGluR3) receptors on neurons and glia. Specifically, NAAG
activation of mGluR receptors reduces cAMP and cGMP levels in
neurons and astrocytes. The neuropeptidases glutamate
carboxypeptidase II and III (GCPII and III), also known as NAAG
peptidases (hereafter "NPs"), are metalloproteases that hydrolyse
NAAG to N-acetylaspartate (NAA) and glutamate following the release
of NAAG into the synaptic cleft. They are found in limited sites
throughout the brain. Inhibition of GCPII and III increases NAAG
levels, with the consequent activation of presynaptic Group II
mGluRs and inhibition of transmitter release, including release of
GABA and glutamate.
[0078] A Group I mGluR antagonist (mGluR1 and mGluR5) can be
administered to the subjects with the compounds employed in the
methods of the invention.
[0079] mGluRs are a heterogeneous family of glutamate G-protein
coupled receptors. mGluRs are classified into three groups. Group I
receptors (mGluR1 and mGluR5) can be coupled to stimulation of
phospholipase C (PLC) resulting in phosphoinositide (PI) hydrolysis
and elevation of intracellular calcium levels, modulation of ion
channels (e.g., potassium channels, calcium channels, non-selective
cation channels) and N-methyl-D-aspartate (NMDA) receptors. mGluR5
can be present on a postsynaptic neuron. mGluR1 can be present on a
presynaptic neuron and/or a postsynaptic neuron.
[0080] Group II receptors (mGluR2 and mGluR3) and Group III
receptors (mGluRs 4, 6, 7, and 8) inhibit cAMP formation and
G-protein-activated inward rectifying potassium channels. Group II
mGluRs and Group III mGluRs are negatively coupled to adenylyl
cyclase, generally present on presynaptic neurons, but can be
present on postsynaptic neurons and function as presynaptic
autoreceptors to reduce glutamate release from presynaptic neurons.
Activation of Group II mGluRs under very high neuron excitation can
dampen further release of neurotransmitters and stimulate the
release of neuroprotective growth factors, including trophic
factors, from glia.
[0081] An antagonist (e.g., a Group I mGluR antagonist, a M1
muscarinic antagonist) is a substance that diminishes or abolishes
the effect of a ligand (e.g., glutamate, acetylcholine) that
activates its receptor (e.g., mGluR1, mGluR5, M1 muscarinic
receptor). The antagonist may act at the level of ligand-receptor
interaction, such as by competitively or non-competitively (e.g.,
allosterically) inhibiting ligand binding. The antagonist (e.g.,
mGluR1 antagonist, mGluR5 antagonist, M1 muscarinic antagonist) can
be, for example, a chemical antagonist or a pharmacokinetic
antagonist. The antagonist, for example, may act downstream of the
receptor, such as by inhibiting receptor interaction with a
G-protein or subsequent cell signaling events associated with
G-protein activation, such as activation of PLC, an increase in
intracellular calcium, the production of or levels of cAMP or
adenyl cyclase and stimulation or modulation of ion channels (e.g.,
potassium channels, calcium channels).
[0082] In one embodiment, the Group I mGluR antagonist is a mGluR5
antagonist. In another embodiment, the Group I mGluR antagonist is
an mGluR1 antagonist. Suitable Group I mGluR antagonists for use
are described in U.S. Pat. Nos. 6,890,931 and 6,916,821, the
teachings of both of which are hereby incorporated by reference in
their entirety. Suitable Group I mGluR antagonists can include, for
example, (E)-6-methyl-2-styryl-pyridine (SIB 1893),
6-methyl-2-phenylazo)-3-pyridinol, x-methyl-4-carboxyphenylglycine
(MCPG) and 2-methyl-6-(phenylthynyl)-pyridine (MPEP).
[0083] Exemplary antagonists of mGluR5 for use in the methods of
the invention in combination with GABA agonists, in particular
GABA(B) agonists (e.g., baclofen), are described in WO 01/66113, WO
01/32632, WO 01/14390, WO 01/08705, WO 01/05963, WO 01/02367, WO
01/02342, WO 01/02340, WO 00/20001, WO 00/73283, WO 00/69816, WO
00/63166, WO 00/26199, WO 00/26198, EP-A-0807621, WO 99/54280, WO
99/44639, WO 99/26927, WO 99/08678, WO 99/02497, WO 98/45270, WO
98/34907, WO 97/48399, WO 97/48400, WO 97/48409, WO 98/53812, WO
96/15100, WO 95/25110, WO 98/06724, WO 96/15099 WO 97/05109, WO
97/05137, U.S. Pat. No. 6,218,385, U.S. Pat. No. 5,672,592, U.S.
Pat. No. 5,795,877, U.S. Pat. No. 5,863,536, U.S. Pat. No.
5,880,112, U.S. Pat. No. 5,902,817, all of which are incorporated
by reference in their entirety. Different classes of mGluR5
antagonists are described in WO 01/08705, WO 99/44639 and WO
98/34907, the teachings of all of which are hereby incorporated by
reference in their entirety.
[0084] The antipsychotic compound employed in the methods of the
invention can be a typical antipsychotic compound (also referred to
as "a typical antipsychotic agent" or a "typical antipsychotic
drug"). In another embodiment, the antipsychotic compound is an
atypical antipsychotic compound (also referred to as an "atypical
antipsychotic agent," an "atypical antipsychotic drug" or a "second
generation antipsychotic").
[0085] Exemplary atypical antipsychotic compounds for use in the
methods of the invention can be at least one member selected from
the group consisting of zuclopenthixol, amisulpride, aripiprazole
(7-[4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butoxy]-3-4-dihydrocarbostyri-
l), nemonapride, abaperidone
(7-[3-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1-piperidinyl]propoxy]-3-(-hydr-
oxymethyl)-4H-1-benzopyran-4-one, U.S. Pat. No. 5,736,588, the
teachings of which are hereby incorporated by reference in its
entirety; belaperidone ((1.alpha., 5.alpha.,
6.alpha.)-3-[2-[6-(4-fluorophenyl)-3-azabicyclo[-3.2.0]-hept-3-yl]ethyl]--
2,4(1H,3H)quinazolinedione, U.S. Pat. No. 5,475,105, the teachings
of which are hereby incorporated by reference in its entirety;
clozapine
(8-chloro-11-(4-methyl-1-piperazinyl)-5H-dibenzo[b,e][1,4]diazepine,
U.S. Pat. No. 3,539,573, the teachings of which are hereby
incorporated by reference in its entirety issued; iloperidone
(1-[4-[3-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1-piperidinyl]-3-methoxy-phe-
nyl]ethanone; EP-402,644, the teachings of which are hereby
incorporated by reference in its entirety; olanzapine
(2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno[2,3-b][1,5]benzodiazepine-
; U.S. Pat. No. 5,229,382, the teachings of which are hereby
incorporated by reference in its entirety; perospirone
(cis-2-[4-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]butyl]-hexahydro-o-1-
H-isoindole-1,3(2H)-dione, U.S. Pat. No. 4,745,117, the teachings
of which are hereby incorporated by reference in its entirety;
risperidone
(3-[2-[4-(6-fluoro-1,2-benzisoxazol-3-yl)piperidino]ethyl]-2-methyl-6,7,8-
,9-tetrahydro-4H-pyrido[1,2-.alpha.]pyrimidin-4-one), U.S. Pat. No.
4,804,663, the teachings of which are hereby incorporated by
reference in its entirety; sertindole
(1-[2-[4-[5-chloro-1-(4-fluorophenyl-1H-indol-3-yl]-1-piperidinyl]eth-yl]-
imidazolidin-2-one), U.S. Pat. Nos. 4,710,500; 5,112,838; and
5,238,945, the teachings of all of which are hereby incorporated by
reference in their entirety; tiospirone
(8-[4-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]butyl]-8-azaspiro[4-0.5]-
decane-7,9-dione), U.S. Pat. No. 4,411,901, the teachings of which
are hereby incorporated by reference in its entirety; ziprasidone
(5-[2-[4-(1,2-benzoisothiazole-3-yl)-1-piperazinyl]ethyl]-6-chloro-1-,3-d-
ihydro-2-one), U.S. Pat. No. 4,831,031, the teachings of which are
hereby incorporated by reference in its entirety; zotepine
(2-[(8-chlorodibenzo[b,f]thiepin-10-yl)oxy]-N,N-dimethyl-ethanamine),
U.S. Pat. No. 3,704,245, the teachings of which are hereby
incorporated by reference in its entirety; quetiapine
(5-[2-(4-dibenzo[b,f][1,4]thiazepin-11-yl-1piperazinyl)ethoxy]ethano-1),
U.S. Pat. No. 4,879,288, the teachings of which are hereby
incorporated by reference in its entirety; and blonanserin
(2-(4-ethyl-1-piperazinyl)-4-(4-fluorophenyl)-5,6,7,8,9,10-hexahydro-1-cy-
cloocta[b]pyridine), U.S. Pat. No. 5,021,421, the teachings of
which are hereby incorporated by reference in its entirety;
2002/0123490, the teachings of which are hereby incorporated by
reference in its entirety).
[0086] Antipsychotic agents, including atypical antipsychotic
compounds for use in the invention can include, for example,
Acetophenazine Maleate; Alentemol Hydrobromide; Alpertine;
Azaperone; Batelapine Maleate; Benperidol; Benzindopyrine
Hydrochloride; Brofoxine; Bromperidol; Butaclamol Hydrochloride;
Butaperazine; Carphenazine Maleate; Carvotroline Hydrochloride;
Chlorpromazine; Chlorprothixene; Cinperene; Cintriamide; Clomacran
Phosphate; Clopenthixol; Clopimozide; Clopipazan Mesylate;
Cloroperone Hydrochloride; Clothiapine; Clothixamide Maleate;
Clozapine; Cyclophenazine Hydrochloride; Droperidol; Etazolate
Hydrochloride; Fenimide; Flucindole; Flumezapine; Fluphenazine
Decanoate; Fluphenazine Enanthate; Fluphenazine Hydrochloride;
Fluspiperone; Fluspirilene; Flutroline; Gevotroline Hydrochloride;
Halopemide; Haloperidol; Iloperidone; Imidoline Hydrochloride;
Lenperone; Loxapine; Mazapertine Succinate; Mesoridazine;
Metiapine; Milenperone; Milipertine; Molindone Hydrochloride;
Naranol Hydrochloride; Neflumozide Hydrochloride; Ocaperidone;
Olanzapine; Oxiperomide; Penfluridol; Pentiapine Maleate;
Perphenazine; Pimozide; Pinoxepin Hydrochloride; Pipamperone;
Piperacetazine; Pipotiazine Palmnitate; Piquindone Hydrochloride;
Prochlorperazine Edisylate; Prochlorperazine Maleate; Promazine
Hydrochloride; Quetiapine; Remoxipride; Quetiapine Remoxipride
Hydrochloride; Risperidone; Risperadone Rimcazole Hydrochloride;
Seperidol Hydrochloride; Sertindole; Setoperone; Spiperone;
Sulpiride; Thioridazine; Thiothixene; Thorazine; Tioperidone
Hydrochloride; Tiospirone Hydrochloride; Trifluoperazine
Hydrochloride; Trifluperidol; Triflupromazine; Ziprasidone
Hydrochloride, analogs, derivative and combinations thereof (see,
for example, U.S. Patent Application Nos: 20040019030 and
2002/0123490, the teachings of both of which are hereby
incorporated by reference in their entirety).
[0087] Antipsychotic compounds can have adverse side effects
including, for example, central nervous system depression, weight
gain, sexual dysfunction, adverse effects on mood, anticholinergic
side effects (cognitive impairment, reduced memory capacity,
confusion, delirium, dry mouth, blurred vision, worsening of
glaucoma, constipation, urinary retention, tachycardia), weight
gain, diabetes mellitus, prolactin elevation, QTC prolongation,
sedation, motor side effects such as extrapyramidal symptoms (EPS),
dystonia, drug-induced parkinsonism, akathisia and potentially
persistent drug-induced movement disorders and motor side effects
such as tardive dyskinesia (see, for example, U.S. Publication No:
2003/0008897, the teachings of which are hereby incorporated by
reference in its entirety). These adverse side effects can reduce
patient compliance and lead to relapses.
[0088] Atypical antipsychotic compounds can reduce psychotic
symptoms with fewer side effects (e.g., extrapyramidal side
effects, rigidity, tremor, akathisia, cognitive impairment) than
typical antipsychotics (see, for example, Citrome, L., et al.,
Postgraduate Medicine 116: (2004)). In addition, atypical
antipsychotics can also reduce aggression, repetitive behaviors,
hallucinations, delusions, amotivation and emotional withdrawal.
However, not all side effects (e.g., weight gain, impaired glucose
tolerance/lipid abnormalities, impaired social interaction) are
eliminated by the use of atypical antipsychotics. Group I mGluR
antagonist have been shown to reduce weight gain and decrease
appetite. Combinations of Group I mGluR antagonists and
antipsychotics in the methods of the invention described herein, in
particular atypical antipsychotics, may diminish or reduce the side
effects of antipsychotic compounds y reducing the dosage required
and increase compliance to thereby treat subjects having conditions
such as mental retardation, fragile X syndrome, Down's syndrome,
autism, pervasive developmental disorders, including pervasive
developmental disorders with no obvious source.
[0089] The methods of the invention can further include the step of
administering at least one member selected from the group
consisting of a nicotinic receptor agonist, an endocannabinoid
receptor antagonist, an AMPA agonist, an antidepressant, an
antipsychotic, an .alpha.2-adrenergic agonist, an anticonvulsant, a
nicotinic receptor agonist, an endocannabinoid receptor antagonist
and an AMPA agonist, which can be administered before, during or
after administration of the Group I mGluR antagonist, M1 muscarinic
receptor antagonist and/or the GABA(B) receptor agonist, to the
human.
[0090] In an embodiment, the GABA receptor agonist is administered
(e.g., before, concomitantly, sequentially or after) the M1
muscarinic receptor agonist.
[0091] In yet another embodiment, the invention method of treating
a subject, comprising the step of administering to a subject having
at least one condition selected from the group consisting of mental
retardation, Down's syndrome, fragile X syndrome and autism a
composition that includes at least one M1 muscarinic antagonist
(also referred to herein as "M1 muscarinic receptor
antagonist").
[0092] The muscarinic acetylcholine (mACh) receptor family consists
of five members (M1, M2, M3, M4 and M5) and belongs to the G
protein-coupled receptor (GPCR) superfamily. A characteristic of
GPCRs is that ligand binding, the initial step in receptor
signaling, elicits a conformational change in the receptor, leading
to the activation of one or more heterotrimeric G proteins.
Mucarinic M1 receptors may preferentially couple to the activation
of PLC by pertussins toxin (PTx)-insensitive G proteins of the Gq
family (Akam, E. C., et al., British J. Pharmacology 132:950-958
(2001)).
[0093] Each muscarinic acetylcholine receptor shares common
features including specificity of binding for the agonists
acetylcholine and carbamylcholine and the classical antagonists
atropine and quinuclidinyl benzilate. Each receptor subtype couples
to a second messenger system through an intervening G-protein. M1,
M3 and M5 receptors stimulate phosphoinositide metabolism whereas
M2 and M4 receptors inhibit adenylate cyclase. The tissue
distribution differs for each subtype. M1 receptors are found in
the forebrain, especially in the hippocampus and cerebral cortex.
M2 receptors are found in the heart and brainstem while M3
receptors are found in smooth muscle, exocrine glands and the
cerebral cortex. M4 receptors are found in the neostriatum and M5
receptor mRNA is found in the substantia nigra, suggesting that M5
receptors may regulate dopamine release at terminals within the
striatum.
[0094] Activity of Gq-coupled, M1 muscarinic (also referred to
herein as "muscarinic M1") acetylcholine receptors can regulate
hippocampal-dependent learning and memory consolidation. M1
muscarinic acetylcholine receptors (mAChRs), the primary Gq-coupled
mAChRs in hippocampus, contribute to hippocampal-dependent
memory.
[0095] M1 muscarinic antagonists, such as scopolamine and atropine,
can abolish or diminish the action of signal transduction pathways
that are mediated by M1 muscaranic receptors. Scopolamine and
atropine are alkaloids (natural, nitrogenous organic bases, usually
containing tertiary amines) from the plant Atropa belladonna. The
presence of an N-methyl group on atropine or scopolamine changes
the activity of the ligand, possibly by preventing a close
interaction between the ligand and the membrane or lipophilic sites
on the receptor. The methyl group may prevent the penetration into
the brain.
##STR00004##
[0096] Exemplary M1 muscarinic receptor antagonists (also referred
to herein as "M1 muscarinic antagonists" or muscarinic M1
antagonists") for use in the methods of the invention, in
combination with a GABA agonist, in particular, a GABA(B) agonist,
can include the following:
[0097] Telenzepine is a racemic, analog that is more potent than
Pirenzepine (Merck, Gastrozepen). Pirenzepine does not cross the
blood brain barrier, but telenzepine may and may have reactive
metabolites. The muscarinic M1 receptor antagonist
(+/-)-telenzepine (about 3 mg orally at about 6 p.m. for about 5
days) has been used to treat chronic obstructive pulmonary disease
(COPD). The results indicate that short-term treatment with
telenzepine does not improve airway function in COPD patients, at
least after administration by the oral route.
[0098] Trihexyphenidyl (Artane) is an antiparkinson agent of the
antimuscarinic class of agents and is chemically a tertiary amine.
The drug is available as the hydrochloride salt.
[0099] Benztropine (Cogentin) (Merck) is an anticholinergenic and
an antihistamine. It has been used in patients with schizophrenia
to reduce the side effects of antipsychotic treatment, such as
parkinsonism and akathisia. Benztropine is also a second-line drug
for the treatment of Parkinson's disease. It improves tremor but
not rigidity or bradykinesia. Benztropine is also sometimes used
for the treatment of dystonia, a rare disorder that causes abnormal
muscle contraction, resulting in twisting postures of limbs, trunk,
or face.
[0100] Dicyclomine (Bentyl) has been used to treat intestinal
hypermotility, the symptoms of Irritable Bowel Syndrome (also known
as spastic colon). It relieves muscle spasms in the
gastrointestinal tract by blocking the activity of a certain
natural substance in the body. It is a smooth muscle relaxer.
Bentyl is also referred to as Byclomine, Dibent, Di-Spaz, Dilomine,
Bentylol (Hoechst Marion Roussel), Formulex (ICN) and Lomine
(Riva).
[0101] Biperiden
(1-(5-bicyclo[2.2.1]hept-2-enyl)-1-phenyl-3-(1-piperidyl)
propan-1-ol) is an antiparkinsonian agent of the anticholinergic
type and is also referred to as Akineton.RTM. (BASF/Knoll
Pharma).
[0102] Procyclidine
(1-cyclohexyl-1-phenyl-3-pyrrolidin-1-yl-propan-1-ol hydrochloride)
has been used to treat schizophrenia to reduce the side effects of
antipsychotic treatment, such as parkinsonism and akathisia.
Procyclidine is also a second-line drug for the treatment of
Parkinson's disease and can improve tremors, but not rigidity or
bradykinesia. Procyclidine may be employed to treat dystonia (but
not tardive dyskinesia), a rare disorder that causes abnormal
muscle contraction, resulting in twisting postures of limbs, trunk,
or face.
[0103] Scopolamine ((-)-(S)-3-Hydroxy-2-phenyl-propionic acid
(1R,2R,4S,7S,9S)-9-methyl-3-oxa-9-aza-tricyclo[3.3.1.02,4]non-7-yl
ester) acts as a competitive antagonist at specific muscarinic
acetylcholine receptors (the M1 receptor). Scopolamine is
classified as an anticholinergic, or, more specifically, as an
anti-muscarinic drug.
[0104] The quaternary muscarinic antagonist ipratroprium and the
long-lasting tiotropium can also be employed.
##STR00005##
[0105] Enantomerically (+, -; R, S; d, l) enriched compositions
(e.g., about 99 mole percent, about 98 mole percent, about 95 mole
percent, about 90 mole percent, about 85 mole percent, about 80
mole percent, about 75 mole percent, about 70 mole percent, about
65 mole percent, about 60 mole percent, about 55 mole percent,
about 51 mole percent of one enantiomer in the composition relative
to the total of both of the enantiomers in the composition) of the
M1 muscarinic antagonists can be employed in the methods described
herein.
[0106] The methods of the invention can further include the step of
administering a stimulant to the subject. "Stimulant," as used
herein, refers to any compound that promotes or increases
wakefulness, alertness, physical activity, enhances cognition,
enhances learning or diminishes fatigue. Stimulants for use in the
invention can include amantadine, bupropion, atomoxetine,
modafinil, caffeine, methylphenidate, nicotine, pseudoephedrine,
and amphetamine, or metabolites, isomers (e.g., d, 1, R, S) or
derivatives thereof. The stimulant used in the methods described
herein can antagonize adenosine receptor, inhibit dopamine
reuptake, inhibit norepinephrine reuptake, antagonize H3 receptor,
promote dopamine release, inhibit monoamine oxidase in the nervous
system (the central nervous system, peripheral nervous system, and
autonomic nervous system) or any combinations thereof.
[0107] The compounds employed in the methods of the invention can
be administered to a subject with (e.g., before, concomitantly,
sequentially or after) administration of other compounds that are
employed to treat a particular disorder or condition in the
subject. For example, the compositions of the invention can be
administered with at least one member selected from the group
consisting of an antidepressant, a Group I mGluR antagonist, a
muscarinic M1 antagonist, an anti-psychotic, an .alpha.2-adrenergic
agonist and an anticonvulsant.
[0108] The identification of appropriate compounds, such as
antidepressants, antipsychotics, .alpha.2-adrenergic agonists,
anticonvulsants, a nicotinic receptor agonist, an endocannabinoid
receptor antagonist and AMPA agonists, for use in the methods of
the invention would be known to one skilled in the art (see, for
example, Beryy-Kravis, E., et al., Mental Retardation and
Developmental Disabilities 10: 42-48 (2004), the teachings of which
are hereby incorporated by reference in its entirety).
[0109] The compounds employed in the methods of the invention can
be administered to the subject acutely (briefly or short-term) or
chronically (prolonged or long-term). For example, subjects can be
administered the compounds for days (1-7), months (1, 2, 3, 4, 5,
6, 7, 8, 9, 10, 11, 12), years (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
12) or for life.
[0110] Subjects treated by the methods of the invention can have at
least one condition selected from the group consisting of a sensory
hyperarousal disorder, an anxiety disorder, a seizure disorder, a
gastrointestinal disorder, a sleep disorder, aggressive or aberrant
behavior and an impaired cognitive function.
[0111] Subjects treated by the methods of the invention can also
have at least one condition selected from the group consisting of a
social interaction abnormality, limited interests and repertoire of
behaviors and a social avoidance condition.
[0112] Subjects (e.g., humans, also referred to herein as
"patients") treated by the methods of the invention can have a
cognitive impairment, such as an impairment in reaction time, eye
tracking, motor coordination, gait, oral-motor function,
communication, learning, attention, executive function, reaction
time, learning, information processing, conceptualization, problem
solving, verbal fluency or memory (e.g., memory consolidation,
short-term memory, working memory, long-term memory, declarative
memory or procedural memory).
[0113] Impairment in a cognitive function treated by the methods
described herein can be an impairment in attention, which is the
capacity or process of selecting out of the totality of available
sensory or affective stimuli, those stimuli that are most
appropriate or desirable for focus at a given time (Kinchla, R. A.,
et al., Annu. Rev. Psychol. 43:711-742 (1992)). The impairment in a
cognitive process can be an impairment in executive function, which
are neuropsychological functions such as decision making, planning,
initiative, assigning priority, sequencing, motor control,
emotional regulation, inhibition, problem solving, planning,
impulse control, establishing goals, monitoring results of action
and self-correcting (Elliott, R., Br. Med. Bull. 65:49-59 (2003)).
The cognitive impairment can be an impairment in alertness,
wakefulness, arousal, vigilance, and reaction time information
processing, conceptualization, problem solving and/or verbal
fluency. One of skill in the art would be capable of identifying
and evaluating the impairment in a cognitive function in the
individual.
[0114] An "effective amount," also referred to herein as a
"therapeutically effective amount," when referring to the amount of
a compound or composition (e.g., baclofen, a M1 muscarinic receptor
antagonist) is defined as that amount, or dose, of a compound or
composition that, when administered to a subject, is sufficient for
therapeutic efficacy (e.g., an amount sufficient decrease to
exhibit a clinical improvement in a behavior or mental cognitive
test score; alleviate sensory hyperarousal disorder, an anxiety
disorder, a seizure disorder, a gastrointestinal disorder, a sleep
disorder, prevent weight gain, decrease obsessive compulsive
tendencies and manners).
[0115] The methods of the present invention can be accomplished by
the administration of the compounds of the invention (e.g.,
compositions including baclofen) by enteral or parenteral means.
The route of administration can be by oral ingestion (e.g., tablet,
capsule form) or intramuscular injection of the compound. Other
routes of administration can include intravenous, intraarterial,
intraperitoneal, or subcutaneous routes, nasal administration,
suppositories and transdermal patches.
[0116] In an embodiment, the compounds (e.g., baclofen, Group I
mGluR antagonists, M1 muscarinic receptor antagonists) employed in
the methods of the invention can be administered in a dose of
between about 0.01 mg/kg to about 0.1 mg/kg; about 0.001 mg/kg to
about 0.01 mg/kg; about 0.001 to about 0.05 mg/kg; about 0.1 mg/kg
to about 1 mg/kg body weight; about 1 mg/kg to about 5 mg/kg body
weight; or between about 5 mg/kg to about 15 mg/kg body weight.
[0117] The compounds can be administered in doses of about 0.1 mg,
about 1 mg, about 2 mg, about 2.5 mg, about 5 mg, about 10 mg,
about 15 mg, about 20 mg, about 25 mg, about 30 mg, about 40 mg,
about 45 mg, about 50 mg, about 60 mg, about 80 mg, 100 mg, about
200 mg, about 250 mg, about 300 mg, about 350 mg, about 400 mg,
about 500 mg, about 600 mg, about 700 mg, about 900 mg, about 1000
mg, about 1200 mg, about 1400 mg, about 1600 mg or about 2000 mg,
or any combination thereof. The compounds can be administered once
a day or multiple (e.g., two, three, four, five) times per day.
[0118] In yet another embodiment, the subject is administered the
compounds employed in the methods of the invention at about 1 mg
BID (twice a day), about 2 mg BID, about 3 mg BID, about 5 mg BID,
about 10 mg BID and about 10 mg TID (three times a day).
[0119] In another embodiment, the compounds employed in the methods
of the invention can be administered at a dosing regimen that
includes progressive or escalating increases in the compound over
time of treatment. For example, a subject can be treated with
baclofen (e.g., R-baclofen, such as between about 20 to about 40 mg
per day) at a dose of about 2 mg/day at days 1, 2, 3 of treatment;
about 4 mg/day at days 4, 5, 6 of treatment; about 6 mg/day at days
7, 8, 9 of treatment; about 20 mg/day at days 13, 14, 15 of
treatment and about 30 mg/day at days 16, 17 and 18 of
treatment.
[0120] The compounds of the invention can be administered to the
human in a selected dose (e.g., about 10 mg dose taken 3 times a
day or about 15 mg dose given as three doses each of which is about
5 mg) while monitoring improvements in the human (e.g., cognition,
behavior). If the human does not exhibit any improvement, the
compositions employed in the methods can be increased, decreased or
stopped until a beneficial effect is observed. For example, if
treatment began with three (3) doses of about 10 mg daily and the
human subsequently exhibited no apparent improvement, the dose
could be increased to three (3) doses of about 15 mg a day,
decreased to two (2) doses of about 10 mg a day or treatment could
be halted for a single dose, a number of days or weeks and
subsequently commenced following the "mini-drug holiday."
[0121] "Mini-drug holiday," as used herein, refers to removal of
the human from treatment or a decrease in the dose of the compound,
followed by re-introduction of the treatment, at a dose equivalent
to, below or in excess of the dose the human received prior to the
mini-drug holiday.
[0122] In yet another embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes baclofen, wherein the baclofen is
administered to the human at a dose of about 2 mg per day for days
1, 2 and 3 of treatment, a dose of about 4 mg per day for days 4, 5
and 6 of treatment, a dose of about 6 mg per day for days 7, 8 and
9 of treatment, a dose of about 10 mg per day for days 10, 11 and
12 of treatment, a dose of about 20 mg per day for days 13, 14 and
15 of treatment, a dose of about 30 mg per day for days 16, 17 and
18 of treatment and a dose between about 15 mg to about 80 mg per
day for the duration of the treatment or between about 30 mg to
about 80 mg per day for the duration of the treatment.
[0123] In an additional embodiment, the invention is a method of
treating a human, comprising the step of administering to a human
having at least one condition selected from the group consisting of
mental retardation, Down's syndrome, fragile X syndrome and autism
a composition that includes baclofen, wherein the baclofen is
administered to the human at a dosing regimen of at least one
member selected from the group consisting of about 1 mg twice a
day, about 2 mg twice a day, about 3 mg twice a day, about 5 mg
twice a day, about 10 mg twice a day and about 10 mg three times a
day.
[0124] One skilled in the art can adjust doses of compounds for use
in the methods. A suitable dose of a compound (e.g., a GABA(B)
agonist, such as baclofen; M1 muscarinic receptor antagonist) for
use in a subject can be a titrated dose. For example, the subject
would initially receive a low dose, doses would be increased if the
low dose was not effective. Doses could be increased about every
3-7 days of treatment, with adjustments as necessary based on
side-effects. The doses can be titrated until the maximal tolerated
dose or maximally effective dose is determined. Subjects can be
maintained at the maximally effective or maximally tolerated
dose.
[0125] In one embodiment, the baclofen administered to the human is
a racemic mixture (50 mole percent R-baclofen and 50 mole percent
S-baclofen). In another embodiment, the baclofen administered to
the human is enriched for one enantiomer of baclofen.
[0126] The enatomerically enriched baclofen can include a
composition that is at least about 51 mole percent, at least about
55 mole percent, at least about 60 mole percent, at least about 65
mole percent, at least about 70 mole percent, at least about 75
mole percent, at least about 80 mole percent, at least about 85
mole percent, at least about 90 mole percent, at least about 95
mole percent, at least about 98 mole percent, at least about 99
mole percent or 100 mole percent R-baclofen relative to the total
R-baclofen and S-baclofen in the composition administered to the
human.
[0127] Alternatively, the enatomerically enriched baclofen can
include a composition that is at least about 51 mole percent, at
least about 55 mole percent, at least about 60 mole percent, at
least about 65 mole percent, at least about 70 mole percent, at
least about 75 mole percent, at least about 80 mole percent, at
least about 85 mole percent, at least about 90 mole percent, at
least about 95 mole percent, at least about 98 mole percent, at
least about 99 mole percent or 100 mole percent S-baclofen relative
to the total S-baclofen and R-baclofen in the composition
administered to the human.
[0128] The compounds employed in the methods of the invention can
be administered alone or can be coadministered to the patient.
Coadministration is meant to include simultaneous or sequential
administration of one or more of the compounds (e.g., baclofen and
a M1 muscarinic receptor antagonist) employed in the methods of the
invention individually or in combination. The mode of
administration can be conducted sufficiently close in time to each
other so that the effects on the subject are maximal. It is also
envisioned that multiple routes of administration (e.g.,
intramuscular, oral, intranasal, inhalation, topical, transdermal)
can be used to administer the compounds employed in the methods of
the invention.
[0129] The compounds employed in the methods of the invention can
be administered alone or as admixtures with conventional
excipients, for example, pharmaceutically, or physiologically,
acceptable organic, or inorganic carrier substances suitable for
enteral or parenteral application which do not deleteriously react
with the compound(s) administered to the subject. Suitable
pharmaceutically acceptable carriers include water, salt solutions
(such as Ringer's solution), alcohols, oils, gelatins and
carbohydrates such as lactose, amylose or starch, fatty acid
esters, hydroxymethycellulose, and polyvinyl pyrrolidine. Such
preparations can be sterilized and, if desired, mixed with
auxiliary agents such as lubricants, preservatives, stabilizers,
wetting agents, emulsifiers, salts for influencing osmotic
pressure, buffers, coloring, and/or aromatic substances and the
like which do not deleteriously react with the compounds employed
in the methods of the invention. The preparations can also be
combined, when desired, with other active substances to reduce
metabolic degradation. A preferred method of administration of the
compounds employed in the methods of the invention can be oral
administration, such as a tablet.
[0130] The compounds employed in the methods of the invention,
alone, or when combined with an admixture, can be administered in a
single or in more than one dose over a period of time to confer the
desired effect (e.g., alleviate symptoms of autism, improve sleep
patterns, decrease sensory hyperarousal disorder, alleviate an
anxiety disorder, a seizure disorder, a gastrointestinal disorder,
an impaired cognitive function, weight gain).
[0131] When parenteral application is needed or desired,
particularly suitable admixtures for the compounds employed in the
methods of the invention are injectable, sterile solutions,
preferably oily or aqueous solutions, as well as suspensions,
emulsions, or implants, including suppositories. In particular,
carriers for parenteral administration include aqueous solutions of
dextrose, saline, pure water, ethanol, glycerol, propylene glycol,
peanut oil, sesame oil, polyoxyethylene-block polymers, and the
like. Ampules are convenient unit dosages. The compounds for use in
the methods of the invention can also be incorporated into
liposomes or administered by transdermal pumps or patches.
Pharmaceutical admixtures suitable for use in the present invention
are well-known to those of skill in the art and are described, for
example, in Pharmaceutical Sciences (17th Ed., Mack Pub. Co.,
Easton, Pa.) and WO 96/05309 the teachings of which are hereby
incorporated by reference.
[0132] The dosage and frequency (single or multiple doses)
administered to an individual can vary depending upon a variety of
factors, including the duration of condition of the subject (e.g.,
sensory hyperarousal disorder, anxiety disorder, seizure disorder,
gastrointestinal disorder, sleep disorder, an impaired cognitive
function, weight gain, obsessive compulsive behaviors); the route
of administration of the compound; size, age, sex, health, body
weight, body mass index, and diet of the recipient; nature and
extent of symptoms of the disorder being treated (e.g., sensory
hyperarousal disorder, anxiety disorder, seizure disorder,
gastrointestinal disorder, sleep disorder, impaired cognitive
function), kind of concurrent treatment (e.g., behavioral
modification, anti-depressant medications, .alpha.2-adrenergic
agonists, anticonvulsants, a nicotinic receptor agonist, an
endocannabinoid receptor antagonist, AMPA agonists,
anti-psychotics), complications from, for example, a sensory
hyperarousal disorder, anxiety disorder, seizure disorder,
gastrointestinal disorder, sleep disorder or impaired cognitive
function; or other health-related problems. Other therapeutic
regimens or agents can be used in conjunction with the methods of
the present invention. For example, the administration of the
compounds employed in the methods of the invention can be
accompanied by behavioral modifications, anti-depressant
medications and anti-psychotic medications. Adjustment and
manipulation of established dosages (e.g., frequency and duration)
are well within the ability of those skilled in the art.
[0133] An additional embodiment of the invention is the use of the
compositions and compounds (e.g., baclofen, M1 muscarinic receptor
agonist, Group I mGluR antagonists) for the manufacture of a
medicament to treat subjects (e.g., humans) having the conditions
described herein (e.g., fragile X syndrome, autism).
[0134] A further embodiment of the invention is a pharmaceutical
composition that includes the compositions and compounds described
herein (e.g., baclofen, M1 muscarinic receptor antagonists, Group I
mGluR antagonists) to treat subjects having the conditions
described herein (e.g., fragile X syndrome, autism).
[0135] A description of example embodiments of the invention
follows. The teachings of all patents, published applications and
references cited herein are incorporated by reference in their
entirety.
EXEMPLIFICATION
Example 1
Treatment of Autism with Baclofen
[0136] A 23 year old female with autism spectrum disorder (height
61'', weight 170 lbs) was hospitalized and being preparing for
port-a-catheter placement to begin TPN for an undetermined period
of time to allow total gut rest. Baclofen was prescribed 5 mg tid
(three times daily) to improve bowel motility. Within about 24
hours abdominal pain appeared to be resolved and GI motility became
functional, allowing oral feeding. Over the next several days and
weeks improvements were noted in cognitive and behavioral domains
that had been unchanged for over 10 years.
[0137] For example, improvements with social interaction as
evidenced by
[0138] a. Increased interest and response to spoken language
[0139] b. Increased spontaneous attempts to interact
[0140] c. Increased joint attention and eye contact;
[0141] improvements in motor coordination as evidenced by
[0142] a. greatly improved oral motor
[0143] b. improved motor planning
[0144] c. improved gait;
[0145] improvements in communication as evidenced by
[0146] a. immediate and appropriate responses to spoken language
(receptive language)
[0147] b. increase in verbal language ("No" "OK" "go") and attempts
at word approximations
[0148] c. increased spontaneous use of augmentative communication
device;
[0149] dramatic improvements in mood and affect "looks comfortable,
calm and happy";
[0150] increased interest and motivation to work on
cognitive/educational activities;
[0151] greatly increased physical stamina and energy;
[0152] increased repertoire of age appropriate behavior and
interests.
[0153] After about 3 weeks of baclofen (about 5 mg tid), the
beneficial effects began to wane. At that time the dose was
increased to about 10 mg tid, but the increase in dose did not
produce the beneficial effects noted above. A single dose of about
15 mg produced the typical side effects of sedation. An alternative
dosing regimen included omission of the evening dose for one day
(e.g., a mini-drug holiday) followed by resumption of the original
dose (about 5 mg tid) the next day, which resulted in beneficial
effects on cognitive and behavioral domains, as described above.
Efficacy has been observed for over about 11 weeks at present at a
dose of about 10 mg bid (twice a day). When positive effects begin
to wane, a single dose is omitted and full efficacy is again
observed. During the first two months it was necessary to skip a
dose about once every 5-7 days to maintain full efficacy, more
recently this interval has increased to once every 10-14 days.
[0154] The improvements observed were in domains that had been
unchanged and stable for over ten years (e.g., communication,
verbalization, joint attention, socialization, coordination),
maximal benefits occurred at doses lower than those typically found
effective for treating gastrointestinal spasticity (the approved
indication), improvements were correlated with a specific dose
range, and tolerance to beneficial effects was not rescued by
increasing the dose but was repeatedly rescued by skipping a single
dose.
[0155] This 23 year old female was on the following medications at
the time of initiation of baclofen: [0156] 175 mg topamax: pain and
history of 4 gran mal seizures (none since 2002); [0157] 30 mg
prevacid bid; [0158] 150 mg zantac tid; [0159] 8 mg zofran every 8
hours to treat chronic vomiting; [0160] 500 mg Philips magnesium
tid to treat constipation; [0161] dulcolax as needed for
constipation; [0162] 100 mg tramadol as needed (every 6-8 hours);
and [0163] oxycodone for breakthrough pain
[0164] This 23 year old female was given a trial of amitryptiline
for 3 days in the hospital prior to baclofen treatment with no
effect. The tramadol and oxycodone were discontinued when the
baclofen was started. Over the past few weeks she was weaned off
many of the above medications. Her current medications are: [0165]
baclofen 20 mg (10 mg twice a day); [0166] topamax 125 mg; and
[0167] zantac 150 mg.
Example 2
Treatment of Autism with Baclofen
[0168] A 12 year old male with autism spectrum disorder
(height=54'', weight=64 lbs) was treated with baclofen. Baclofen
(about 5 mg bid) was initially administered with baclofen in an
attempt to reduce gastroesophageal reflux symptoms. Over the next
several days and weeks improvements were noted in several cognitive
and behavioral domains such as increased interest and response to
spoken language and attempts to communicate verbally. Dramatic
improvements in mood and affect such as "looks comfortable, calm
and happy" were also noted. Increased alertness, interest and
motivation to work on cognitive/educational activities with school
instructors were also noted. School personnel record behavior on a
daily basis, are not informed regarding changes in drug treatment
and did not know that baclofen had been prescribed for this
subject. Daily scores were averaged over the five weeks after
initiating baclofen therapy and compared to the average scores for
the five weeks immediately preceding initiation of baclofen
therapy. Significant improvements following initiation of baclofen
were noted in the following domains: [0169] Episodes of scratching,
hitting and kicking others decreased from an average of 17+2
(mean.+-.SE) to 6+1 episodes a day episodes a day. [0170] Episodes
of hand biting or hitting of the head decreased to from an average
of 15+2 to 6+1 episodes a day. [0171] Episodes of eye diversion
decreased from an average of 10+2 to 5+2 episodes a day.
[0172] These benefits have been maintained for 5 weeks on stable
dosing at 5 mg bid.
[0173] Concommitant medications at the time of initiation of
baclofen: [0174] Tegretol 800 mg/day for history of 4 gran mal
seizures [0175] Prevacid 30 mg bid [0176] Lamotrigine 25 mg/day
[0177] Singulair 5 mg/day [0178] Carafate 1 gm bid
Example 3
Treatment of Autism with Baclofen
[0179] A 9 year old male with autism spectrum disorder
(height=46'', weight=47 lbs) was treated with baclofen. Baclofen (5
mg bid) was initiated in an attempt to reduce gastroesophageal
reflux symptoms. Over the next several days and weeks improvements
were noted in cognitive and behavioral domains, such as increased
interest and response to spoken language and spontaneous attempts
to communicate. Parents also noted an improvement in sleep
patterns, mood and affect. Increased alertness, interest and
motivation to work on cognitive/educational activities were noted
by school personnel. School personnel record behavior on a daily
basis, are not informed regarding changes in drug treatment and did
not know that baclofen had been prescribed for this subject. Daily
scores were averaged over the five weeks after initiating baclofen
therapy and compared to the average scores for the five weeks
immediately preceding initiation of baclofen therapy. Improvements
were noted in the frequency of startle/tremor activity, which is
thought to reflect brief (approximately 2 second duration) seizure
activity in this subject. After initiation of baclofen treatment,
episodes of startle tremor decreased from an average of 66+24
(mean.+-.SE) to 16+5 episodes a day. Similarly, the incidence of
spontaneous attempts to communicate increased from an average of
11+1 to 21+2 episodes a day.
[0180] These benefits have been maintained for 5 weeks on stable
dosing at 5 mg bid.
[0181] Concommitant medications at the time of initiation of
baclofen: [0182] Tegretol 800 mg/day for history of seizures [0183]
Prevacid 30 mg bid [0184] Lamotrigine 50 mg/day [0185] Singulair 10
mg/day
Example 4
Autism Spectrum Disorder with Baclofen
[0186] Racemic baclofen was administered to treat twenty one (21)
subjects (12 males and 9 females) with autism spectrum disorder
(see Table 1). The subjects had serious behavioral problems that
were not controlled with a variety of medications including
antiepileptics (N=14), antipsychotics (N=8) and antidepressants
(N=6). Doses of baclofen administered to the subjects were titrated
on a weekly basis from about 2.5 mg twice a day (BID) to a maximum
of about 15 mg three times a day (TID), with a maximum duration of
treatment of about 8.5 months.
[0187] The clinician rated overall impression of improvement with
baclofen treatment on a seven category scale ranging from "much
worse," "worse," "slightly worse," "no change," "slightly better,"
"better" or "much better." Subjects undergoing baclofen treatment
were considered to have improved if the clinician rating was either
"much better" or "better." Likewise, baclofen was considered to not
improve the condition of the subject if the clinician rating was
"slightly worse," "no change" or "slightly better." If a subject
was worse on baclofen treatment, the clinician rating would be
"worse" or "much worse."
[0188] Eight (8) of the 21 subjects demonstrated improvement in
presenting symptoms including less irritability/aggression, better
communication or improved social interaction. Other areas of
improvement included increased class participation and decreased
hyperactivity. Eleven (11) subjects did not improve and two (2)
subjects worsened. Eight (8) subjects did not continue on baclofen
treatment. These included 2 who did not improve, 1 patient who
improved but did not continue treatment, 3 patients who stopped for
unrelated reasons, and 2 who had adverse side effects that were
considered related to initiation of baclofen treatment (drowsiness
in one and hyperactivity in the other). Other adverse effects
included difficulty sleeping, otitis, increased gastrointestinal
discomfort/loose stools and increase in finger stims.
[0189] Racemic baclofen has been used to treat spasticity and has a
well-defined safety profile in adults and children. There is no
rationale for prescribing baclofen to children with disorders of
brain development. In the patients with fragile X syndrome, doses
of racemic baclofen were titrated from a starting dose of about 2.5
or about 5 mg BID to a maximum of about 20 mg TID, with a maximum
duration of 4 months. Two of five patients demonstrated improvement
in behavior, including less irritability, aggression and agitation,
two are still undergoing titration, and treatment was discontinued
in one subject who developed sleepiness and irritability when the
dose was increased to about 20 mg/day. Other areas of improvement
included increased class participation and decreased hyperactivity.
Of note, all fragile X syndrome patients (Example 5) were receiving
psychoactive drugs and four of five were receiving concurrent
treatment with atypical antipsychotics. In the patients with
idiopathic autism, doses were titrated from about 2.5, 5 or 10 mg
BID to a maximum of about 15 mg TID, with a maximum duration of
about 8.5 months. Eight of the 21 patients demonstrated improvement
in presenting symptoms, including less irritability/aggression,
better communication/social interaction, and decreased frequency
and severity of gastrointestinal symptoms. Other areas of
improvement included increased class participation and decreased
hyperactivity. Baclofen treatment was discontinued in eight
patients including one who improved, five who did not improve and
two patients who worsened (increased hyperactivity in both). Of
note, these patients were commonly receiving concurrent treatment
with psychoactive drugs including antiepileptics (N=14),
antipsychotics (N=8) and antidepressants (N=6). The overall
impression was that baclofen was particularly useful for treatment
of irritable and aggressive behavior.
TABLE-US-00001 TABLE 1 Baclofen Treatment in Autism Spectrum
Disorder Patients Reason for Maximum Treatment Adverse Concomitant
Concomitant Baclofen Total Daily Dose Duration Areas of Events/ Age
(Yrs) Weight (kg) Sex Conditions Medications Treatment (mg)
(months) Ongoing Overall Improvement.sup.1 Improvement
Discontinuation 14 -- F None Risperdal, agitation 20 7.5 Y Not
Improved calmer after None fluoxitine, first few weeks valproic
acid 29 -- M None fluoxetine, compulsions 40 4 Y Not Improved
repetitive/self- None Abilify, stimulatory Remeron behaviors 37 --
F Bipolar mood Risperdal, agitation, 20 1 N Not Improved slightly
calmer hospitalized disorder Synthroid, dystonia with sepsis from
Temazepam, a UTI related to baclofen, poor communication
benztropine and side effects of risperidone (which pre-existed
baclofen)/baclofen discontinued 15 59.1 F Mental retardation
Trileptol, aggression, 45 3.5 Y Improved calmer, None Seroquel,
rigidity, brighter, Lexapro insistence on decreased sameness
aggression, more compliant, decreased screaming 14 50 F Mental
retardation Lithobid, aggression, 20 5.5 Y Improved calmer, None
Lithium irritability, happier carbonate, constant appearance,
Seroquel movement decreased irritability, dramatic decrease in
aggression (10 BID) 4 22 M Lactose Vitamin gastrointestinal 5 1 N
Not Improved calm at first; increased loose intolerance, chronic
cocktail, dysfunction, zone out week stools/ diarrhea, suspected
Pepcid, Vit. behavioral 2-3, D/C by not improved metabolic problem,
B6, A, D, symptoms week 5 increased Nystatin, Zinc, (questionable
illness/fevers in Colostrum dosing during winter (symptoms Gold
vacation) of autism decreased during these periods), history of
regression 20 mos. 13 65.2 M GI tract issues, Vitamin restrictive,
10 4.5 N Improved easygoing, None/ undefined cocktail (CO
repetitive able to tolerate Discontinued metabolic issues, QID, B1,
B2, behaviors, stress/transitions, baclofen to see processing E)
decreased behavior, if changes were problems-needs energy level
more signing, directly related augmentative able to sleep to
baclofen (may communication more/consistently, re-start) device for
language G Ifunction more comfortable 12 50.1 F Seizures, reflux,
Paxil, GI distress, 5 >1 N Not Improved None None/ unspecified
Donovex behavioral No change metabolic disorder, ointment, symptoms
psoriasis, anxiety, omeprazole, PICA, weight loss, Atarax,
dysphagia Depakote 9 50.7 M esophagitis, allergy, Singulair, GI
tract 20 1 Y Improved Happier, "went back to questionable Prevacid,
issues, sleep improved old self" on metabolic disorder, Camitine,
problems, articulation, higher dose (10 distractibility, rash,
Vitamin behavior initiates BID) sleep problems, cocktail (CO,
interactions, gluten and casein- Q10, E, C, B1, B2) stomach better,
free diet increase in sounds (language) 7 29.1 M reflux, sour
Lexapro, GI and 20 7 Y Not Improved Improved None stomach, no
Prevacid, behavioral mood, appetite, suspected Vitamin issues
tolerates metabolic disorder, cocktail (CO, crowds, attention
problems, Q10, E, C, B1, B2) calmer, more anxiety, depression,
social and chronic skin interactive, eruptions on face sleeping
through night, no sour stomach, decreased anxiety 32 81.2 M
seizures, Depakote, GI tract 20 3 Y Not Improved pleasant, None
esophagitis, reflux, propranolol, issues, reflux increase in
constipation, omeprazole, obsessions, hypertyroidism, Singulair,
especially anxiety, bursitis, Keppra, music making, agitation,
Risperdal, better aggression, Synthroid transition, tiredness/low
increase in energy level hand tremors, wants to be social, requires
naps/sleeping better, increase in brief seizures (has history),
ability to retrieve language/use more words 9 33 M stomach pains,
Vitamin B, C, GI concerns, 15 1 Y Not Improved improved takes
longer to GERD, increased omega fatty anxiety, mood, less fall
asleep, acylcarnitine, acids, impulsivity aggressive, slight
increase in auditory sensitivity, Prevacid, language finger stims
anxiety, recurrent Creon improvement, mouth sores, improved
allergic to eggs and BMs, more soy focused on environment, calmer 6
25 M Landau-Kleffner Periactin, Significant 10 3 N Not Improved
elated/no pain, otitis (a week Syndrome, grade 2 Depakote,
abdominal calmer, more after starting esophagitis, Prevacid, pain,
crying interactive (all baclofen)/ abdominal pain, Singulair,
during first major confirmed Bentyl, week); all management
metabolic Donnatal, symptoms issues with other diagnosis, possible
Vitamin returned medication migraines, crying cocktail, despite
dosage episodes, carafate, Milk adjustments regressions in HX of
Magnesia 15 45.5 M anxiety Kondremal, severe 20 1 N Worsened More
engaged, increased Pentasa, abdominal positive sleep hyperactivity;
Thazadose, distress, change, BMs; increased GI Tenex constipation
all during 1st discomfort and week only, crying after 1st then
returned week to baseline 21 65 F Weekly seizures, Depakote, severe
GI 10 <1 N Not Improved None more drowsy severe abdominal
Lamictal, issue (discontinued) distention/constipation,
levothyroxine, hypothyroid, Prevacid respiratory distress 9 25 M
Seizures, GERD, Singulair, GI disorders 10 8.5 Y Improved
happier/more None abdominal pain, Miralax, comfortable,
constipation, Prevacid, behavior esophagitis, rectum Lamictal,
better, more stromal Tegretol, alert, more fibrosis/reactive
Diastat social/interactive hyperplasia accudial, improved
suggestive of Vitamin sleep, mucosal prolapse, cocktail, decreased
mitochondrial Pentasa seizures, dysfunction, decreased eczema
constipation, better able to stay on task 14 33.2 M Seizures,
ulcers, Vitamin GI tract 10 8.5 Y Improved happier, hyperactivity
gastritis, cocktail, issues, calmer, more (but "happy"),
esophagitis, Carafate, lethargy focused, better sleeping at
diarrhea, Lamictal, control over school constipation, Tegretol,
body, more GERD, GI nodular Prevacid, aware of lymphoid Singulair,
surroundings, hyperplasia, Carnitine decrease in presumed
self-injurious mitochondrial behaviors with disorder GI flare-ups,
decreased seizures, decreased frequency/severity of GI issues,
improved toileting 19 93 M increased CPK, Carnitine, behavioral 10
7 Y Improved more even, not None anxiety, +PPD, -CXR Celexa,
symptoms, aggressive, Zyrtec, constipation, less rocking, Nicomide,
GERD more Risperdal, appropriate Adderall socially, constipation no
longer an issue, more pleasant 8 26.4 F Daily seizures, Prevacid,
GI tract 20 <1 N Worsened None increased reflux, abdominal
Pepcid, issues, hyperactivity pain, orthopedic Carafate,
irritability (discontinued) disabilities (wheel Depakote, chair
confined) Lamictal, Miralax, Camitor, Keppra 11 35.2 F non-specific
colitis, Dipentum, GI 10 5.5 Y Not Improved mood/affect, None
irritable bowel, Ultrase MT disorder/GU behavior, reflux,
overgrowth 12, Pepto disorder, repetitive syndrome, GI Bismol,
Carb- behavior behaviors, motility issues, Digest, social
metabolic/mitochondrial Sporanox, interaction, disorder, Vitamin C,
sleep, GI potential pernicious Magnesium, function (hard puberty,
irritable Ditropan, to rule out bladder, minimal Miralax, other
bilateral Flagyl, Cardex variables), pelviectasis, sleep better
bladder disturbance, control oromotor apraxia, small pituitary
.sup.1Clinician's overall impression of improvement with baclofen:
Improved includes "much better" and "better"; Not Improved includes
""slightly better" and "no change"; Worsened includes "worse" and
"much worse"
Example 5
Fragile X Syndrome
[0190] Racemic baclofen was administered to treat five (5) male
subjects with fragile X syndrome (Table 2). These subjects had
serious behavioral problems that were incompletely controlled with
typical psychoactive medications. Baclofen was added to concomitant
antipsychotic treatment in four (4) of the five (5) subjects. Doses
were titrated from about 2.5 mg BID to a maximum of about 20 mg
TID, with a maximum duration of about 4 months. Clinicians rated
their overall impression of improvement with baclofen treatment on
a seven category scale ranging from "much worse," "worse,"
"slightly worse," "no change," "slightly better," "better" or "much
better". Subjects were considered "Improved" if the clinician
rating was either "much better" or "better"; considered "Not
Improved" if the rating was "slightly worse", "no change" or
"slightly better"; and considered "Worsened" if rated "worse" or
"much worse". Two of the 5 patients demonstrated an improvement in
behavior, including less irritability, aggression and agitation.
Other areas of improvement included increased class participation
and decreased hyperactivity. Two subjects did not demonstrate
obvious improvement and the dosing regimen is still being adjusted.
One subject worsened as evidenced by excessive sleepiness,
increased irritability, screaming and swearing and baclofen was
discontinued.
TABLE-US-00002 TABLE 2 Baclofen Treatment in Fragile X Patients
Maximum Treatment Age Weight Concomitant Reason for Baclofen Total
Daily Duration Overall Areas of (Yrs) (kg) Medications Treatment
Dose (mg) (months) Ongoing Improvement.sup.1 Improvement 6 27
Abilify, Agitation, head-banging, 10 4 Y Improved Decreases in all
Risperdal fecal smearing aberrant behaviors; increased class
participation 17 68 Zoloft Severe aggression, self- 20 3.5 Y
Improved Decreased abusive behavior, biting irritability and
hyperactivity; fewer outbursts 20 96 Abilify, Celexa, Aggression,
yelling, 20 1 N Worsened None Xanax, lithium cursing 21 76 Abilify,
Cogentin Agitation, anxiety, 60 3 Y Not Improved Decreases in
vomiting behaviors for 1.sup.st week of treatment 26 61 Abilify,
Trileptal Aggression, agitation 30 2 Y Not Improved Decreased
outbursts for 3-4 weeks .sup.1Clinician's overall impression of
improvement with baclofen: Improved includes "much better" and
"better"; Not Improved includes ""slightly better" and "no change";
Worsened includes "worse" and "much worse"
Example 6
Treatment of Fragile X Knockout Mice with a GABA(B) Agonist
Racemic Baclofen
[0191] Commercially marketed baclofen (Sigma Chemical Co., St.
Louis, Mo.) is a 50:50 racemic mixture of the R- and S-isomers. In
order to better understand the binding affinity of racemic baclofen
the Side Effect Database (SED) was licensed from Novascreen
Biosciences Corporation (Hanover, Md.). The Side Effect Database
includes 76 molecular targets screened against 10 .mu.M racemic
baclofen in duplicate. These targets may be key mediators of side
effects of baclofen, off-target effects and therapeutic targets.
According to the Side Effect Database, baclofen was found to be
selective for GABA-B and to less than about 50% binding at 10 .mu.M
to the other 75 molecular targets.
[0192] The experiments described herein in these preclinical
studies demonstrate efficacy for racemic baclofen on a wide range
of pharmacologic, physiologic and behavioral assays. Racemic
baclofen reduces marble burying behavior in Fmr1 knockout mice
(FIG. 1). Marble burying behavior is believed to reflect anxiety
related, obsessive/compulsive and perseverative responding and,
thus, mimics symptoms commonly observed in subjects with fragile X
syndrome and other disorders of brain development.
R-Baclofen
[0193] The R-isomer of baclofen (R-baclofen) is a more potent
GABA-B agonist than the S-isomer. The binding affinity for the
R-(about 99% R-baclofen) and S-(about 99% S-baclofen) isomers of
baclofen (purchased from Sigma Chemical Co., St. Louis, Mo.) was
assessed. Both R-- and S-- baclofen were assayed at 10 .mu.M in
duplicate against 74 molecular targets (29 neurotransmitter related
targets, 1 steroid, 3 ion channels, 1 second messenger, 4 growth
factors/hormones, 13 brain/gut peptides, 12 general enzymes, 9
kinases, and 2 cell based and functional targets). Testing
confirmed that R- and S-baclofen are selective agonists of GABA-B
and also that the R-isomer is a more potent GABA-B agonist than the
S-isomer (Table 3). As shown in Table 3 GABA(B) binding assay was
performed using rat cortical membranes. IC50 and Ki values indicate
that R-baclofen is about 10 to about 15 times more potent than
S-baclofen and R-/S-baclofen is intermediate in potency.
TABLE-US-00003 TABLE 3 Isomer(s) IC50 Ki R-baclofen 1.23 .times.
10.sup.-6 6.24 .times. 10.sup.-7 S-baclofen 1.66 .times. 10.sup.-5
8.59 .times. 10.sup.-6 R-/S-baclofen 2.96 .times. 10.sup.-6 1.51
.times. 10.sup.-6
[0194] Dose-response relationships for racemic (R-/S-) baclofen and
each of the single isomers (R- or S-baclofen) on marble burying
behavior was assessed. R-baclofen was more potent than S-baclofen
as an inhibitor of marble-burying behavior (FIGS. 2 and 3). Marble
burying behavior is believed to reflect anxiety related,
obsessive/compulsive and perseverative behavior and thus mimic
symptoms commonly observed in subjects with fragile X syndrome
(FXS) and other disorders of brain development.
[0195] R-baclofen is more potent for inhibition of audiogenic
seizures than S-baclofen (FIG. 4). Increased susceptibility to
audiogenic seizures in Fmr1 knockout (KO) mice is believed to model
the increased prevalence of seizure disorders in subjects with
fragile X syndrome.
Marble Burying Assay
Experimental Aim
[0196] The goal of the experiment was to determine if
marble-burying behavior is reduced following administration of the
GABA-B receptor agonist R-baclofen and/or S-baclofen. In these
experiments, Fmr1 KO mice received an i.p. injection of either
R-baclofen or S-baclofen and were tested for marble-burying
behavior.
Results
[0197] The results of the experiment demonstrate that R-baclofen
and S-baclofen alter marble-burying behavior in Fmr1 KO mice. There
was a significant dose-related alteration in marble burying
behavior in Fmr1 KO mice that received an i.p. injection of
R-baclofen 1 hr. before testing. Specifically, Fmr1 KO mice that
received a dose of 10 mg/kg buried significantly less marbles than
mice that received 0, 0.3, 1, 3, or 6 mg/kg. There was also a
significant dose-related alteration in marble burying behavior in
Fmr1 KO mice that received an i.p. injection of S-baclofen 1 hr.
before testing. Specifically, mice that received 1.0 mg/kg buried
significantly more marbles than 0.0 mg/kg treated mice. In
addition, mice that received 50 mg/kg buried less marbles then mice
receiving 0, 0.3, 1, 6 or 30 mg/kg S-baclofen.
Conclusions
[0198] The findings from this experiment indicate that there is a
dose related reduction in marble burying behavior in Fmr1 KO mice
treated with R-baclofen indicating that R-baclofen reduces the
types of anxiety-like/obsessive/repetitive behaviors assessed in
this assay. In addition, S-baclofen altered marble-burying behavior
in a dose related manner, however, at the 1 mg/kg dose. Fmr1 KO
mice actually buried more marbles, suggesting that this dose may
have an effect opposite to the desired effect. Fmr1 KO mice that
received about a 50 mg/kg dose, buried fewer marbles indicating
that this high dose reduces this type
anxiety-like/obsessive/repetitive behaviors assessed in this assay.
These data indicate that R-baclofen may be more suitable than
S-baclofen for reducing this type of
anxiety-like/obsessive/repetitive behaviors simulated by the marble
burying test.
Fragile X (Fmr1), Knock Out (KO) Mice
[0199] Fmr1 KO mice on a C57BL/6J (9 generations) genetic
background were provided by The Jackson Laboratory (Bar Harbor,
Me.). C57BL/6J was backcrossed to establish N11 generation Fmr1
mice. All mice for the current study were generated by mating Fmr1
heterozygous female mice with Fmr1 wild-type male mice. Only male
Fmr1 KO (Fmr1.sup.-/y) mice were tested in this study. Mice were
housed 2-5 per cage in a room with a 12 hr light: dark cycle
(lights on at 6 AM, off at 6 PM) with access to food and water ad
libitum. Male mice that were 2-4 months of age (20-30 grams) were
used for all experiments. In general, behavioral testing was
performed between 9 AM and 3 PM. At the start of testing the mice
were 3-4 months of age. An experimenter who was blind to the
genotypes of the mice conducted the experiments.
[0200] Animals were genotyped by standard PCR techniques. For
detection of the Fmr1 WT allele (527 bp product), PCR was performed
on DNA from tails with primers Fmr1_S1
(5'GTGGTTAGCTAAAGTGAGGATGAT-3'; SEQ ID NO: 1) and Fmr1_S2
(5'CAGGTTTGTTGGGATTAACAGATC-3'; SEQ ID NO: 2). The Fmr1 KO allele
(501 bp product) was detected by PCR with the Fmr1_S1 primer and
primer Fmr1 N2 (5'TGGGCTCTATGGCTTCTGA-3'; SEQ ID NO: 3) which binds
to a Neo cassette that replaced exon 5 of the Fmr1 gene. Cycle
conditions were identical for both S1/S2 and S1/N2 combinations: 2
min at 94.degree. C., 30 s at 55.degree. C., 60 s at 72.degree.
C.), 10 min at 72.degree. C. using standard PCR reagents.
Methods
[0201] A standard mouse cage was filled with 10 cm of corn-cob
bedding. Twenty (20) small (1.5-2 cm) black marbles was placed
equidistant (about 1-2 cm apart) on top of the bedding. A mouse was
placed in the cage and allowed to explore and burry the marbles.
After about 20 minutes the mouse was removed and the number of
marbles buried (a marble is said to be "buried" if more than 50% of
it is under the bedding) was recorded.
[0202] Baclofen and placebo were administered to the mice one hour
prior to training, by intraperitoneal (i.p.) injections, in a
volume of 0.1 ml/10 mg body weight.
[0203] Mice were injected (i.p.) with a dose of R(+)- or
S(-)-baclofen one hour before testing. Each mouse was injected with
a dose of R or S before testing. The order of treatment (e.g., R
followed by S, or S followed by R) was balanced, and the dose was
randomly assigned for each drug. There were at least 3 days between
tests.
[0204] At the time of the test, a mouse was placed at an end of the
cage containing marbles and allowed 20 minutes to bury marbles.
After the 20-minute test, the mice were removed and the marbles
buried were counted. A marble was identified as `buried` if at
least about 50% of it was covered with bedding. After testing mice
were returned to their home cage. The following number (N) of mice
were used for the various R(+)-baclofen doses: N=16, 0 mg/kg; N=15,
0.3 mg/kg; N=15, 1.0 mg/kg; N=10, 3.0 mg/kg; N=13, 6.0 mg/kg; N=10,
10 mg/kg. The following number (N) of mice were used for the
various S(-)-baclofen doses: N=15, 0 mg/kg; N=13, 0.3 mg/kg; N=14,
1.0 mg/kg; N=12, 6.0 mg/kg; N=11, 30.0 mg/kg; N=14, 50 mg/kg.
[0205] Marbles buried were manually scored on a data sheet by an
experimenter that was blind to the genotype and treatment. The data
were then manually entered into a computer-spreadsheet.
[0206] The data were analyzed with a two-way (dose X treatment
order) ANOVA. Significant main effects of dose were then analyzed
using Least Square follow-up comparisons. Statistical analyses were
analyzed using SPSS 11.0.
Results
Racemic Baclofen
[0207] Administration of racemic baclofen (6 mg/kg, 12 mg/kg) to
fragile X knockout mice reduced marble burying behavior in a dose
dependent manner (FIG. 1).
R(+)-Baclofen
[0208] FIG. 2 shows that there was a significant (p<0.005)
dose-related alteration in marble burying behavior in Fmr1 KO mice
that received an i.p. injection of R-baclofen one hour before
testing. Specifically, Fmr1 KO mice that received a dose of 10
mg/kg buried significantly less (p<0.05) marbles then mice that
received 0, 0.3, 1, 3, or 6 mg/kg. The effect of treatment order
was not statistically significant (p>0.05).
S(-)-Baclofen
[0209] FIG. 3 shows that there was also a significant (p<0.005)
dose-related alteration in marble burying behavior in Fmr1 KO mice
that received an i.p. injection of S-baclofen one hour before
testing. Specifically, mice that received 1.0 mg/kg buried
significantly (p<0.05) more marbles than 0.0 mg/kg treated mice.
In addition, mice that received 50 mg/kg buried significantly less
(p's<0.05) marbles then mice receiving 0, 0.3, 1, 6, or 30 mg/kg
S-baclofen. The effect of treatment order was not statistically
significant (p>0.05).
Conclusion
[0210] The findings from this experiment indicate that there is a
dose related reduction in marble burying behavior in Fmr1 KO mice
treated with racemic baclofen. When administered separately,
R-baclofen reduces the types of anxiety-like/obsessive/repetitive
behaviors assessed in this assay. S-baclofen also altered
marble-burying behavior in a dose related manner, however, at the 1
mg/kg dose, Fmr1 KO mice actually buried more marbles, suggesting
that this dose may have an effect opposite to the desired effect.
Fmr1 KO mice that received a 50 mg/kg dose, however, did bury fewer
marbles indicating that this high dose reduces the types
anxiety-like/obsessive/repetitive behaviors assessed in this assay.
Together the findings suggest that R-baclofen may be more suitable
than S-baclofen for reducing the type of
anxiety-like/obsessive/repetitive behaviors simulated by the marble
test.
Audiogenic Seizure Assay
Experimental Aim
[0211] The goal of the experiment was to determine if the
sensitivity to audiogenic seizures in are reduced in Fmr1 KO mice
following administration of the GABA-B receptor agonist R-baclofen
and/or S-baclofen. In these experiments, Fmr1 KO mice received an
i.p. injection of either R-baclofen or S-baclofen and tested for
the audiogenic seizures.
Results
[0212] The results of the experiment demonstrate that
R(+)-baclofen, but not S(-)-baclofen, reduces audiogenic seizures
in Fmr1 KO mice. About 70-80% of vehicle-treated and
S(-)-baclofen-treated (3 mg/kg) Fmr1 KO mice display an audiogenic
seizure. In contract, only 33% of Fmr1 KO mice treated with 3 mg/kg
R(+)baclofen display seizures.
Conclusions
[0213] The findings show that that R(+)-baclofen, but not
S(-)-baclofen, reduced audiogenic seizures in Fmr1 KO mice and that
R-baclofen is more effective than S-baclofen for reducing this type
of environmentally-induced seizure in Fmr1 KO mice.
Methods
[0214] The methods employed in audiogenic seizure experiments as
previously described (Yan, Q. J., et al., Genes Brain Behav.
3:337-359 (2004); Yan, Q. J., et al., Neuropharm. 49:1053-1066
(2005)). Briefly, Fmr1 knockout mice were treated i.p. with either
vehicle, R-baclofen or S-baclofen about 60 minutes prior to the
assay. Mice were exposed to a high intensity sound and then
observed for occurrence of seizures. The primary endpoint was
frequency of status epilepticus, a sustained tonic seizure most
often resulting in respiratory arrest and death.
[0215] Test and control articles were administered to the mice one
hour prior to training, via intraperitoneal (i.p.) injections, in a
volume of 0.1 ml/10 g body weight.
[0216] Mice were injected (i.p.) with a dose of R(+)- or
S(-)-baclofen 45-min before testing. Each mouse was injected with a
dose of R or S before testing. Mice used for this study were
experimentally naive.
[0217] Two-three mice were placed into a clean cage with bedding
and transferred from their holding cage into a sound attenuated
chamber. The cage was placed under a lid that contained two Radio
Shack Personal Alarms. After 1 min the alarm sound was turned on
for two minutes. After this two-minute exposure mice were given
another minute of no sound followed by a second two-minute alarm.
The presence of seizures as defined by `non-startling` wild-running
or tonic/clonic seizures were recorded. In our test protocol, mice
do not display a seizure during the first alarm period.
[0218] The following number (N) of mice were used for the study: 0
mg/kg N=10; 3 mg/kg R(+)-baclofen N=9; and 3 mg/kg S(-)-baclofen
N=9.
[0219] The presence of seizures as defined by `non-startling`
wild-running or tonic/clonic seizures were recorded. In addition,
the latency to wild-running and/or tonic/clonic seizures was
recorded. The percentage of mice displaying seizures was analyzed
using SPSS 11.0.
Results
[0220] R-baclofen (3 mg/kg) significantly prevented induction of
audiogenic seizures whereas S-baclofen at the same dose was no more
effective than vehicle (FIG. 4).
[0221] FIG. 4 shows that about 70% of vehicle-treated Fmr1 KO mice
displayed audiogenic seizures. Similarly, about 78% of Fmr1 KO mice
treated with about 3 mg/kg S(-)-baclofen displayed seizures. In
contract, only about 33% of Fmr1 KO mice treated with 3 mg/kg
R(+)-baclofen displayed seizures.
Conclusion
[0222] These findings suggest that R-baclofen is likely to be more
effective than S-baclofen for reducing this type of
environmentally-induced seizure in Fmr1 KO mice.
Open Field Testing
Experimental Aim
[0223] The goal of the experiment was to determine if open-field
activity in Fmr1 KO mice is altered following administration of the
GABA-B receptor agonist R-baclofen and/or S-baclofen. In these
experiments, Fmr1 KO mice received an i.p. injection of either
R-baclofen or S-baclofen and tested for open-field activity.
Results
[0224] The results of the experiment demonstrate that R(+)-baclofen
and S(-)-baclofen reduced open-field activity in Fmr1 KO mice.
Relative to vehicle-treated wild type (WT) littermate controls,
vehicle-treated Fmr1 KO mice were significantly more active in the
open-field as measured by total activity. There was a significant
dose-related reduction in exploratory activity as measured by total
distance in Fmr1 KO mice that received an i.p. injection of R(+)-
or S(-)-baclofen 1 hr before testing. Specifically, Fmr1 KO mice
that received a dose of 6 mg/kg R(+)-baclofen were less active
(reduced total distance) compared to Fmr1 KO mice that received
vehicle. Similarly, Fmr1 KO mice that received a dose of 50 mg/kg
R(+)-baclofen were less active (reduced total distance) compared to
Fmr1 KO mice that received vehicle.
Conclusions
[0225] These data show that there was a dose related reduction in
exploratory activity in Fmr1 KO mice treated with R(+)- or
S(-)-baclofen. Similar to individuals with fragile X syndrome, male
Fmr1-deficient mice were more active, but this increased activity
as measured by the total distance traveled in the open-field arena,
can be normalized by baclofen. The data suggest that the dose
required for S-baclofen that reduces exploratory activity in Fmr1
KO mice is greater than that required for R-baclofen-treated mice.
Thus, R-baclofen may be more effective than S-baclofen for reducing
the type of increased activity stimulated by the open-field
test.
Methods
[0226] Test and control articles were administered to the mice one
hour prior to training, via intraperitoneal (i.p.) injections, in a
volume of 0.1 ml/10 g body weight.
[0227] Mice were injected (i.p.) with a dose of R(+)- or
S(-)-baclofen one hour before testing. Each mouse was injected with
a dose of R or S before testing. The order of treatment (e.g. R
followed by S, or S followed by R) was balanced, and the dose was
randomly assigned for each drug. There were at least 3 days between
tests. Mice used for this experiment had been previously tested
approximately one week earlier on the marble-burying test following
treatment with R(+)- and S(-)-baclofen.
[0228] Mice were placed into the center of a clear Plexiglas (40
cm.times.40 cm.times.30 cm) open-field arena and allowed to explore
for 30 minutes. Bright, overhead lighting provided approximately
800 lux of illumination inside the arenas. White noise was present
at approximately 55 dB inside the arenas. Total distance traveled
data during the 30 minute test were collected in two-min intervals
by a computer-operated Digiscan optical animal activity system
(Accuscan Electronics), but the data for the full 30-min test were
analyzed.
[0229] The following number (N) of mice were used for the various
R(+)-baclofen doses: N=12, 0 mg/kg; N=13, 1.0 mg/kg; N=13, 6.0
mg/kg. The following N were used for the various S(-)-baclofen
doses: N=12, 0 mg/kg; N=14, 1.0 mg/kg; N=12, 50 mg/kg. The N for
the WT littermate controls were: R(+)-baclofen vehicle-treatment
N=14; S(-)-baclofen vehicle-treatment N=16.
[0230] Open-field activity data were analyzed using a two-step
process. First, the data from vehicle-treated WT and Fmr1 KO
littermates were analyzed using a one-way ANOVA. Next, the Fmr1 KO
data for the three doses of each compound were analyzed to
determine if the treatment significantly alter the behavior of the
Fmr1 KO mice. Statistical analyses were analyzed using SPSS
11.0
Results
R(+)-Baclofen
[0231] FIG. 5 shows that there was a significant (p<0.001)
increase in locomotor activity in vehicle-treated Fmr1 KO mice
compared to vehicle-treated WT controls. In addition, there was a
dose-related alteration in total distance traveled in Fmr1 KO mice
that received an i.p. injection of R-baclofen 1 hr before testing.
Fmr1 KO mice that received a dose of 6 mg/kg were significantly
less active (p=0.018) then mice than vehicle-treated Fmr1 KO
mice.
S(-)-Baclofen
[0232] FIG. 5 shows that there was a significant (p<0.05)
increase in locomotor activity in vehicle-treated Fmr1 KO mice
compared to vehicle-treated wild type (WT) controls. In addition,
there was a dose-related alteration in total distance traveled in
Fmr1 KO mice that received an i.p. injection of S(-)-baclofen 1 hr
before testing. Specifically, Fmr1 KO mice that received a dose of
50 mg/kg were significantly less active (p=0.021) then mice than
vehicle-treated Fmr1 KO mice.
Conclusions
[0233] These data show there is a dose related reduction in
locomotor activity in Fmr1 KO mice treated with R(+)-baclofen
indicating that R(+)-baclofen reduces Fmr1 KO hyperactivity as
assessed in this assay. In addition, S-baclofen reduced Fmr1 KO
activity in a dose related manner. A lower dose of R(+)-baclofen
was effective at reducing Fmr1 KO hyperactivity relative to
S(-)-baclofen. R(+)-baclofen may be more suitable than
S(-)-baclofen for reducing the type of hyperactivity in Fmr1 KO
mice stimulated by the open-field test.
Pre-Clinical Summary
[0234] R-baclofen was more than 10-fold more potent than S-baclofen
as a GABA-B agonist (Table 3) and also more potent for inhibition
of marble-burying behavior (FIGS. 2 and 3). Similarly, R-baclofen
is more potent for inhibition of audiogenic seizures than
S-baclofen (FIG. 4) and open field testing (FIG. 5).
Example 7
Treatment of Fragile X Knock Out Mice with a M1 Muscarinic Receptor
Antagonist
[0235] Dicyclomine reduces marble burying behavior in Fmr1 knockout
mice (FIG. 6). Marble burying behavior is believed to reflect
anxiety related, obsessive/compulsive and perseverative responding
and thus mimic symptoms commonly observed in subjects with fragile
X syndrome and other disorders of brain development. Similarly,
dicyclomine inhibited audiogenic seizures in Fmr1 knockout mice
(FIG. 7). Increased susceptibility to audiogenic seizures in Fmr1
knockout mice is believed to model the increased prevalence of
seizure disorders in subjects with FXS.
Marble Burying Assay
Methods
[0236] Fmr1 KO mice were bred on a C57BL/6J genetic background.
Only male Fmr1 KO (Fmr1-/y) mice were tested in this study. A
standard mouse cage was filled with 10 cm of corn-cob bedding.
Small (1.5-2 cm) black marbles were placed equidistant on top of
the bedding. A mouse was placed in this cage and allowed to explore
and bury the marbles. After about 20 minutes the mouse was removed
and the number of marbles buried (a marble was considered `buried`
if more than about 50% of the marble under the bedding) was
recorded. Mice were treated with dicyclomine about 60 minutes
before the test.
Results
[0237] Fmr1 knockout mice in this background strain buried more
marbles than wild type (wt) littermates. Administration of
dicyclomine reduced marble burying behavior in a dose dependent
manner (FIG. 6).
Conclusion
[0238] These data show there is a dose related reduction in marble
burying behavior in Fmr1 KO mice treated with dicyclomine.
Dicyclomine reduced the types of anxiety-like/obsessive/repetitive
behaviors assessed in this assay.
Audiogenic Seizure Assay
Methods
[0239] The methods employed are described above. Briefly, Fmr1
knockout mice were treated i.p. with either vehicle or dicyclomine
about 60 minutes prior to the assay. Mice were exposed to a high
intensity sound and then observed for occurrence of seizures. The
primary endpoint was frequency of status epilepticus, a sustained
tonic seizure most often resulting in respiratory arrest and
death.
Results
[0240] Dicyclomine significantly prevented induction of audiogenic
seizures (FIG. 7).
Conclusion
[0241] These data show that dicyclomine effectively rescues seizure
in Fmr1 KO mice.
EQUIVALENTS
[0242] While this invention has been particularly shown and
described with references to preferred embodiments thereof, it will
be understood by those skilled in the art that various changes in
form and details may be made therein without departing from the
scope of the invention encompassed by the appended claims.
Sequence CWU 1
1
3124DNAArtificial SequencePrimer 1gtggttagct aaagtgagga tgat
24224DNAArtificial SequencePrimer 2caggtttgtt gggattaaca gatc
24319DNAArtificial SequencePrimer 3tgggctctat ggcttctga 19
* * * * *