Note: Descriptions are shown in the official language in which they were submitted.
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
METHODS FOR REGULATING NEUROTRANSMITTER SYSTEMS BY
INDUCING COUNTERADAPTATIONS
CROSS-REFERENCE To RELATED APPLICATIONS
[0001] This application is a continuation-in-part under 35 U.S.C. 120
of*U.S. Patent
Applicatiqn serial number 11/234,850, filed on September 23, 2006, which in
turn claims
the benefit under 35 U.S.C. 119(e) of U.S. Provisional Patent Application
serial number
60/612,155 entitled "COUNTER-ADAPTATION THERAPY FOR TREATMENT OF
DEPRESSION AND OTHER MENTAL CONDITIONS," and filed on September 23,
2004. This application also claims priority to U.S. Provisional Patent
Application serial
number 60/777,190, entitled "METHOD OF REGULATING THE CRF AND AVP
SYSTEMS BY INDUCING COUNTERADAPTATIONS," and filed on February 27,
2006; and to U.S. Provisional Patent Application serial number 60/858,186,
entitled
"OPIATE ANATOGONISTS FOR COUNTERADAPTATION THERAPY," and filed on
November 9, 2006. The above-referenced provisional application is hereby
incorporated
herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0002] The present invention relates generally to neurotransmitter systems.
The present
invention relates more particularly to methods for regulating these
neurotransmitter
systems by inducing counteradaptative responses.
2. Technical Back ound
[0003] Mood, mood disorders and related conditions are a result of a complex
web of
central nervous system events that interrelate many neurotransmitter systems.
A most
common mood disorder is depression. Depression is a clinical diagnosis with
numerous
somatic and mental symptoms, which is due to an alteration of numerous
neurotransmitter
systems. While the neurotransmitter systems most commonly related with
depression are
the norepinephrine and serotonin systems, current research indicates that
other systems,
such as the substance P system, the dynorphin system (kappa receptors), the
endogenous
endorphin system (mu and delta opiate receptors), the corticotropin releasing
factor system,
and the arginine vasopressin systems are also involved in depression. Further,
these
neurotransmitter systems are also related to a whole host of other undesirable
mental,
1
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
neurological and physiological conditions, including bipolar disorders,
obsessive-
compulsive disorders, anxiety, phobias, stress disorders, substance abuse,
sexual disorders,
eating disorders, motivational disorders, pain disorders, cardiovascular
disorders, aging-
related disorders, and immune-system related disorders.
[0004] Conventional strategies for treating neurotransmitter-linked conditions
are centered
on improving abnormally high or low levels of synaptic neurotransmitters.
Conventional
therapeutic agents work to directly regulate the functioning of the
neurotransmitter
systems. Such agents may be anxiolytic agents, hypnotic agents, or selective
reuptake
inhibitors, and include benzodiazepines (e.g., diazepam, lorazepam,
alprazolam,
temazepam, flurazepam, and chlodiazepoxide), TCAs, MAOIs, SSRIs (e.g.,
fluoxetine
hydrochloride), NRIs, SNRIs, CRF modulating agents, serotonin pre-synaptic
autoreceptor
antagonists, 5HT1 agonist, GABA-A modulating agents, serotonin 5H2c and/or
5HZB
modulating agents, beta-3 adrenoceptor agonists, NMDA antagonists, V1B
antagonists,
GPCR modulating agents, dynorphin antagonists, and substance P antagonists.
[0005] Conventional therapeutic agents and methods, while somewhat effective,
suffer
from a few disadvantages. For example, use of many conventional therapeutic
agents is
attended by side effects, such as sexual dysfunction, nausea nervousness,
fatigue, dry
mouth, blurred vision and weight gain. Further, patients can adapt or build up
a resistance
to conventional therapeutic agents with repeated use, making them lose
efficacy over time.
SUMMARY OF THE INVENTION
[0006] One aspect of the present invention relates to a method of regulating a
neurotransmitter system by inducing a counteradaptation in a patient, the
neurotransmitter
system including a type of receptor, the method comprising: repeatedly
administering to
the patient a ligand for the type of receptor, each administration having an
administration
half-life, thereby causing the ligand to bind receptors of that type during a
first time period
associated with each administration, thereby inducing, maintaining or
improving a
counteradaptation, wherein the counteradaptation causes the regulation of the
neurotransmitter system, and wherein the ratio of the administration half-life
to the period
between administrations is no greater than 1/2.
. 2
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0007] In one aspect of the invention, the neurotransmitter system is the SP
system; the
type of receptor is SP receptors; the ligand is an SP receptor agonist; and
the
counteradaption causes a down-regulation of the SP system.
[0008] In another aspect of the invention, the neurotransmitter system is the
endogenous
endorphin system; the type of receptor is mu and/or delta opiate receptors;;
the ligand is a
mu and/or delta opiate receptor agonist; and the counteradaption causes an up-
regulation of
the endogenous endorphin system.
[0009] In yet another aspect of the invention, the neurotransmitter system is
the dynorphin
system; the type of receptor is kappa receptors; the ligand is a kappa
receptor agonist; and
the counteradaption causes a down-regulation of the dynorphin system.
[0010] In still yet another aspect of the invention, the iieurotransmitter
system is the
serotonin system; and the counteradaption causes an up-regulation of the
serotonin system.
Thus, in one embodiment of this aspect of the invention, the type of receptor
is serotonin
pre-synaptic autoreceptors; and the ligand is a serotonin pre-synaptic
autoreceptor agonist.
In another embodiment of this aspect of the invention the type of receptor is
serotonin post-
synaptic receptors; and the ligand is a serotonin post-synaptic autoreceptor
antagonist.
[0011 ] In still yet another aspect of the invention, the neurotransmitter
system is the
norepinephrine system; and the counteradaption causes an up-regulation of the
norepinephrine system. Thus, in one embodiment of this aspect of the
invention, the type
of receptor is norepinephrine pre-synaptic alpha-2 adrenergic receptors; and
the ligand is a
norepinephrine pre-synaptic alpha-2 adrenergic receptor agonist. In another
embodiment of
this aspect of the invention the type of receptor is norepinephrine post-
synaptic adrenergic
receptors; and the ligand is a norepinephrine post-synaptic adrenergic
receptor antagonist.
[0012] In still yet another aspect of the invention, the neurotransmitter
system is the CRF
system; the type of receptor is CRF receptors; the ligand is a CRF receptor
agonist; and the
counteradaptation causes a down-regulation of the CRF system.
[0013] In still yet another aspect of the invention, the neurotransmitter
system is the CRF
system; the type of receptor is CRF receptors; the ligand is a CRF receptor
antagonist; and
the counteradaptation causes a up-regulation of the CRF system.
3
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0014] In still yet another aspect of the invention, the neurotransmitter
system is the AVP
system; the type of receptor is AVP receptors; the, ligand is a AVP receptor
agonist; and the
counteradaptation causes a down-regulation of the AVP system.
[0015] In still yet another aspect of the invention, the neur'otransmitter
system is the AVP
system; the type of receptor is AVP receptors; the ligand is a AVP receptor
antagonist; and
the counteradaptation causes a up-regulation of the AVP system.
[0016] In yet another embodiment of the invention, a method is provided for
inducing a
regulation of a neurotransmitter system, the neurotransmitter system including
a type of
receptors linked to an undesirable mental, neurological or physiological
condition. The
method comprising the step of: repeatedly administering to the patient a
ligand for the type
of receptor, each administration having an administration half-life, thereby
causing the
ligand to bind a substantial fraction of receptors of that type during a first
time period
associated with each administration, thereby inducing a counteradaptation;
wherein the
counteradaptation causes the regulation of the neurotransmitter system during
a second
time period associated with each administration, the second time period being
subsequent
to the first time period.
[0017] In yet another aspect of the present invention, the methods described
herein are
used to address or treat an undesirable mental, neurological or physiological
condition in a
patient, the undesirable mental, neurological or physiological condition being
linked to
receptors of the type of receptor.
[0018] In yet another aspect of the present invention, the methods described
herein are
used to address or treat an undesirable immune system-related condition in a
patient in
need thereof, the immune-system related condition being linked to receptors of
the type of
receptors, the method resulting in an up-regulation of the immune system.
[0019] In yet another aspect of the present invention, the methods described
herein are
used to address or treat a cariovascular or lipid or cholesterol metabolism-
related condition
in a patient in need thereof, the cariovascular or lipid or cholesterol
metabolism-related
condition being linked to receptors of the type of receptor.
[0020] In yet another aspect of the present invention, the methods described
herein are
used to address or treat insufficient preparedness for a future athletic
activity.
4
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0021] In yet another aspect of the present invention, the methods described
herein are
used to address or treat an undesirable condition linked to the Sirtl pathway.
[0022] The methods of the present invention result in a number of advantages
over prior art
methods. For example, the methods of the present invention can be used to
address a
whole host of undesirable mental, neurological and physiological conditions
with reduced
side effects. In certain embodiments of the invention, the desired therapeutic
benefit can be
timed to coincide with a desired time of day or task to be performed by the
patient.
[0023] Additional features and advantages of the invention will be set forth
in the detailed
description which follows, and in part will be readily apparent to those
skilled in the art
from the description or recognized by practicing the invention as described in
the written
description and claims hereof, as well as in the appended drawings.
[0024] It is to be understood that both the foregoing general description and
the following
detailed description are merely exemplary of the invention, and are intended
to provide an
overview or framework for understanding the nature and character of the
invention as it is
claimed.
[0025] The accompanying drawings are included to provide a further
understanding of the
invention, and are incorporated in and constitute a part of this
specification. The drawings
are not necessarily to scale, and sizes of various elements may be distorted
for clarity. The
drawings illustrate one or more embodiment(s) of the invention, and together
with the
description serve to explain the principles and operation of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a graph of in vivo ligand concentration (part a) and mood vs.
time (part b)
according to one embodiment of the invention;
[0027] FIG. 2 is a graph of mood vs. time for several administrations of a
ligand according
to another embodiment of the invention;
[0028] FIG. 3 is a graph of in vivo ligand concentration vs. time for the
administration via a
single injection of a ligand with a relatively long compound half-life;
[0029] FIG. 4 is a graph of in vivo ligand concentration vs. time for the
administration via
time-release transdermal patch of a ligand with a relatively short compound
half-life;
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0030] FIG. 5 is a graph of in vivo ligand concentration vs. time for the
administration via
time-release transdermal patch of a ligand with a relatively short compound
half-life, when
the patch is removed during the administration; and
[0031] FIG. 6 is a graph of in vivo ligand concentration (part a) and mood vs.
time (part b)
according to another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0032] The present invention relates generally to the regulation of
neurotransmitter systems
by exploiting the patient's response to a pharmaceutical agent (a
"counteradaptation"),
rather than by relying on the direct effect of the agent for an improved
clinical effect. In
general, pharmaceutical agents are chosen so that the counteradaptation is
beneficial to the
patient and eventually provides the desired long-term effect. The methods of
the present
invention differ from conventional methods in that the direct effect of the
agent is a
modulation of neurotransmitter receptors that is generally associated with a
worsening of
symptoms. In response to the direct effect of the agent, however, the brain
responds by a
counteradaptation, resulting in the desired regulation of the neurotransmitter
system when
any direct effect of the agent wears off. The regulation may be any change in
neurotransmitter system functioning, and may be, for example, an up-regulation
or a down-
regulation. A specific acute response is induced directly in order to generate
a desired
long-term effect indirectly. In a simple analogy, just as euphoria-stimulating
agents such
as morphine and cocaine result in depression upon their withdrawal, dysphoria-
stimulating
agents result in "anti-depression" upon their withdrawal.
[0033] One embodiment of the present invention relates to a method of a
regulating a
neurotransmitter system. Generally, a neurotransmitter system is a system of
natural
neurotransmitter compounds and synaptic receptors that participates in central
nervous
system signal transmission. The neurotransmitter system includes a type of
receptors. The
type of receptors may be, for example, linked to an undesirable mental,
neurological or
physiological condition. FIG. I includes a graph of in vivo ligand
concentration versus
time for a method according to one embodiment of the invention. As illustrated
in FIG. 1,
the method includes the step of repeatedly administering to a patient a ligand
for the type of
receptor, thereby causing the ligand to bind receptors of that type during a
first time period
associated with each administration. As used herein, a ligand is a compound
that binds to
6
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
(e.g., interacts with in either a covalent or non-covalent fashion) receptors
of the type of
receptor, and may be, for example, an agonist for the receptor or an
antagonist for the
receptor. The binding of the ligand to the receptors induces a
counteradaptation, which
causes the regulation of the neurotransmitter system. FIG. 1 shows a couple of
administrations of ligand occurring in the middle of the method, and not the
first couple of
administrations. Each administration is a single cycle in which the in vivo
concentration of
the ligand begins at a baseline level, goes up to a maximum level, and drops
back down to
the baseline level. The graph of FIG. 1 shows two such administrations.
Depending on the
dosing regimen, each administration of the ligand may be performed, for
example, by
giving the patient a single unit dose (e.g., pill, capsule) or injection;
multiple unit doses or
injections; or continuously (e.g., intravenous or slow-release patch).
[0034) Examples of types of neurotransmitter systems and types of receptors
with which
the method may be practiced include the Substance P system, in which the type
of
receptors may be NK-1, NK-2 and/or NK-3 receptors; the endogenous endorphin
system in
which the type of receptors may be mu and/or delta opiate receptors; the
dynorphin system
in which the type of receptors may be kappa receptors; the serotonin system in
which the
type of receptors may be inhibitory serotonin pre-synaptic autoreceptors
(e.g., 5HTIA
and/or 5HTiB autoreceptors) and/or serotonin post-synaptic receptors (e.g.
5HTt, 5HT2,
5HT3, 5HT4, 5HT5, 5HT6 and/or 5HT7 receptors); the norepinephrine system in
which the
type of receptors may be inhibitory norepinephrine pre-synaptic alpha-2
adrenergic
receptors and/or norepinephrine post-synaptic adrenergic receptors; the
corticotropin
releasing factor (CRF) system, in which the type of receptors may be CRF
receptors (e.g.
CRF-1 receptors and/or CRF-2 receptors; and the arginine vasopressin (AVP)
system, in
which the type of receptors may be AVP rececptors (e.g., V1R, also known as
Via, V2R
and/or V3R, also known as V lb). These neurotransmitter systems and receptor
types are
linked to various undesirable mental, neurological and physiological
conditions, as would
be appreciated by the skilled artisan.
[0035] In certain aspects of the invention, an undesirable mental,
neurological or
physiological condition is linked to a type of receptor in the
neurotransmitter system. If the
undesirable mental, neurological or physiological condition is exacerbated by
the binding
of the receptor to its natural neurotransmitter, then it is said to be
"positively linked" to that
type of receptor. Conversely, if the undesirable mental, neurological or
physiological
condition is improved by the binding of the receptor to its natural
neurotransmitter, then it
7
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
is "negatively linked" to that type of receptor. For example, the undesirable
mental,
neurological or physiological condition of depression is negatively linked to
serotonin post-
synaptic receptors, because binding of these receptors to their natural
neurotransmitter
serotonin results in a decrease in the depression. The undesirable mental,
neurological or
physiological condition of depression is positively linked to kappa receptors,
because
binding of these receptors to their natural neurotransmitter dynorphin results
in an increase
in the depression.
[0036] Instead of relying on the direct effect of ligand-receptor binding to
regulate the
neurotransmitter system, the methods of the present invention exploit the
indirect
counteradaptive effect to enhance or suppress neurotransmitter systems. The
counteradaptation is the brain's natural response to the binding of the
ligand. The initial
effect of ligand binding may be a worsening of an undesirable mental,
neurological or
physiological condition linked to the neurotransmitter system. However,
because the
effects of the counteradaptation last long after the ligand is removed from
the system, and
can build up over repeated administration of the ligand, the counteradaptation
causes an
overall desirable regulation of the neurotransmitter system. The regulation of
the
neurotransmitter system can, in turn, provide a therapeutic benefit with
respect to the
undesirable mental, neurological or physiological condition. The regulation of
the
neurotransmitter system may be, for example, an increase in the
counteradaptive response
(as shown in FIG. 2, described below), or a maintenance of an already-induced
counteradaptive response (as shown in FIG. 6, described below).
[0037] Counteradaptations are a manner by which the central nervous system
maintains
homeostasis. The counteradaptation is a result of the body's attempt to
regulate the
neurotransmitter system to its original steady-state level in order to prevent
its over- or
under-stimulation. Natural neurotransmitters bind with their receptors for
only a short
time, and are removed almost immediately from the synapse, and therefore do
not cause a
counteradaptive response. When a ligand interacts with a receptor for a longer
period of
time (e.g., because the ligand has a longer binding time or is continuously
administered),
however, cellular mechanisms gradually occur at the receptor/neurotransmitter
level that
act to counteract the direct effects of the ligand-receptor binding (i.e., the
counteradaptation). The counteradaptation may be, for example, a change in the
biosynthesis or release of a natural neurotransrnitter that binds to the type
of receptor, a
change in the reuptake of a natural neurotransmitter that binds to the type of
receptor, a
8
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
change in the number of the type of receptors and/or binding sites on
receptors of the type
of receptor, a change in the sensitivity of receptors of the type of receptor
to binding by the
natural neurotransmitter and/or receptor agonists, or any combination thereof.
Chronic use
of a ligand thus induces (i.e., causes) a counteradaptation by stimulating
processes that
oppose the initial effects of the ligand, which over time results in a
decrease in the effect of
ligand-receptor binding.
[0038] When the ligand is a receptor agonist, the counteradaptation works to
reduce the
functioning of the neurotransmitter system (i.e., a down-regulation"). The
down-
regulation may occur through, for example, a decrease in the biosynthesis or
release of a
natural neurotransmitter that binds to the type of receptor, an increase in
the reuptake of a
natural neurotransmitter that binds to the type of receptor, a decrease in the
number of the
type of receptors and/or binding sites on receptors of the type of receptor, a
decrease in the
sensitivity of receptors of the type of receptor to binding by the natural
neurotransmitter
and/or receptor agonists, or any combination thereof. Any of the above-recited
counteradaptive responses will work to reduce the functioning of the
neurotransmitter
system, and can therefore provide a therapeutic benefit with respect to an
undesirable
mental, neurological or physiological condition that is positively linked to
the
neurotransmitter system.
[0039] Conversely, when the ligand is a receptor antagonist, the
counteradaptation works
to increase the functioning of the neurotransmitter system (i.e., an `up-
regulation"). The
up-regulation may occur through, for example, an increase in the biosynthesis
or release of
a natural neurotransmitter that binds to the type of receptor, a decrease in
the reuptake of a
natural neurotransmitter that binds to the type of receptor, an increase in
the number of the
type of receptors and/or binding sites on receptors of the type of receptor,
an increase in the
sensitivity of receptors of the type of receptor to binding by the natural
neurotransmitter
and/or receptor agonists, or any combination thereof. Any of the above-recited
counteradaptive responses will work to increase the functioning of the
neurotransmitter
system, and therefore provide a therapeutic benefit with respect to an
undesirable mental,
neurological or physiological condition that is negatively linked to the
neurotransmitter
system.
[0040] Receptors in the brain are commonly regulated by a pre-synaptic
negative inhibition
control loop. Thus, for mood-elevating post-synaptic receptors (i.e.,
receptors negatively
9
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
linked to an undesirable mental, neurological or physiological condition), it
is desirable to
use repeated agonist treatment at the associated inhibitory pre-synaptic
receptors. Repeated
agonist administration at a pre-synaptic inhibitory receptor results in a down-
regulation of
that receptor, lessening its inhibitory response and thereby increasing neural
firing at the
mood-elevating post-synaptic receptors and providing an elevation of mood.
[0041] An opposite strategy is desired for use with mood-depressing post-
synaptic
receptors (i.e., receptors positively linked to an undesirable mental,
neurological or
physiological condition). For such receptors, it is desirable to use repeated
antagonist
treatment at the associated inhibitory pre-synaptic receptors. Repeated
antagonist
administration at a pre-synaptic inhibitory receptor results in an up-
regulation of that
receptor, lessening its inhibitory response and thereby decreasing neural
firing at the mood-
depressing post-synaptic receptors and providing an elevation in mood.
[0042] The direct effect of the ligand binding during the first time period
will often be an
initial exacerbation of an undesirable mental, neurological or physiological
condition
linked to the type of receptor. For example, when the administered ligand is
an antagonist
for a type of receptor Iinked negatively to an undesirable mental,
neurological or
physiological condition, the short-term effect of the binding is to block the
receptors and
prevent them from binding the natural neurotransmitter and firing. Similarly,
when the
administered ligand is an agonist for a type of receptor positively linked to
an undesirable
mental, neurological or physiological condition, the short term affect of the
binding is to
cause the receptors to fire. Both the firing of receptors positively linked to
the undesirable
mental, neurological or physiological condition and the prevention of the
firing of receptors
negatively linked to the undesirable mental, neurological or physiological
condition can
cause an initial worsening of symptoms. When the short-term effect of ligand-
receptor
binding wears off (e.g., due to the removal of ligand from the system), the
counteradaptation remains to provide the desired regulation of the
neurotransmitter system.
Repeated administration can cause a gradually increasing regulation of
neurotransmitter
systems. In certain embodiments of the present invention described below,
measures are
taken to limit the effect on the patient of the direct effect of ligand-
receptor binding.
[0043] FIG. 1 also includes in part (b) a graph of mood vs. time for
administration of an
appropriate ligand for a mood-associated receptor. As shown in the example
ofFIG. 1, the
direct effect of ligand administration may be a worsening of mood during each
first time
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
period. This worsening of mood tapers off as the in vivo concentration of the
ligand falls to
its steady state level. After the ligand concentration returns to its low
steady state level, the
counteradaptation remains in place to provide an overall improvement in mood
during a
second time period associated with each administration and subsequent to the
first time
period. FIG. 2 is a graph of mood vs. time for several administrations of a
ligand during a
method according to the present invention. As evidenced in FIG. 2 by the ever-
increasing
mood (i.e., the graph generally slants up with time), the strength of the
counteradaptation
may build up with time, with each administration causing additional
counteradaptive
response. As such, an increasing therapeutic benefit may be realized with
repeated
intermittent administration of the ligand. While FIGS. 1 and 2 depict an
example in which
the counteradaptation causes a net increase in mo.od, the skilled artisan will
recognize that
the methods described herein will be useful to treat any number of
neurotransmitter-linked
conditions, including those described in more detail hereinbelow.
[0044] Each administration of the ligand has an administration half-life. As
shown in the
graph of part (a) of FIG. 1, the in vivo concentration of the ligand is at a
relatively low
baseline level at the beginning of the administration (e.g., the swallowing of
a pill, the
application of a transdermal patch, or the beginning of intravenous
administration), then
rises to some maximum level. After reaching a maximum, the in vivo
concentration of the
ligand will decrease back down to the baseline level (e.g., due to
metabolism/excretion of
the ligand), where it remains until the next administration. As shown in FIG.
1, the
administration half-life is measured as the period of time between the
beginning of the
administration and the half-maximum point of the in vivo concentration as the
concentration drops from its maximum level to the baseline level.
[0045] The administration half-life will be a function of the compound half-
life (i.e., the
half-life in vivo of the ligand compound itself) as well as of the route of
administration.
For example, FIG. 3 is a graph of in vivo concentration versus time for a
single
administration via injection of a ligand with a relatively long compound half-
life. Because
the injection gets the ligand into the bloodstream very quickly, the
administration half-life
approximates the compound half-life. In the example of FIG. 4, a ligand with a
much
shorter compound half life (e.g., a peptide) is administered using a time-
release transdermal
patch. Here, the concentration rises more slowly to a steady state maximum
concentration,
then falls off as the patch becomes depleted. Were the patch removed before
depletion, the
in vivo concentration would decrease rapidly down to the baseline level, as
shown in FIG.
11
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
5. The administration half-life may be, for example, less than about a week,
less than about
three days, or less than about a day. More desirably, the administration half-
life is less than
about sixteen hours; less than about twelve hours, less than about eight
hours; or less than
about four hours. In certain embodiments of the invention, especially those
using a ligand
having a relatively long compound half-life, the administration half-life may
be greater
than about four hours; greater than about twelve hours; greater than about
sixteen hours; or
greater than about thirty hours.
[0046] The ligand has a compound half-life, defined as the in vivo half life
of the ligand
and its active metabolites (i.e., metabolites that are active at receptors of
the type of
receptor), divorced from any effects due to the route of administration. In
certain
embodiments of the present invention, it may be desirable to use a compound
with a
relatively short compound half-life. For example, in certain embodiments of
the invention
the compound half-life is less than about a week, less than about three days,
or less than
about a day. More desirably, the compound half-life is less than about sixteen
hours; less
than about twelve hours, less than about eight hours; or less than about four
hours; or less
than one hour. Some ligands, however, have relatively longer compound half-
lives. For
example, in certain embodiments of the invention, the compound half-life of
the ligand is
greater than about four hours; greater than about twelve hours; greater than
about sixteen
hours; or greater than about thirty hours.
[0047] The period between administrations is desirably selected so as to
maximize the
counteradaptive response to the ligand while maintaining an acceptably low and
tolerable
direct effect of ligand-receptor binding. For example, the administration of
the ligand may
be performed daily. In other embodiments of the invention, the period between
administrations is two days or greater; three days or greater; five days or
greater; one week
or greater; two weeks or greater; or one month or greater. Similarly, the dose
of the ligand
at each administration is selected to be sufficient to trigger a
counteradaptive response, but
low enough that direct effects of ligand-receptor binding are low and
tolerable to the
patient.
[0048] When using a ligand having a compound half-life greater than about
twelve hours,
in order to increase the counteradaptation it may be desirable to repeatedly
administer a
second ligand for the type of receptor, with each administration of the second
ligand having
an administration half-life of less than about eight hours. In an example of a
method
12
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
according to the present invention, a ligand having a twenty-four hour
compound half-]ife
is administered every three days with a twenty four hour administration half-
life, and a
second ligand is administered daily with a six hour administration half-life.
In such cases,
when the ligand is a receptor agonist, the second ligand is desirably a
receptor agonist; and
when the ligand is a receptor antagonist, the second ligand is desirably a
receptor
antagonist.
[0049] The ratio of administration half life to the period between
administrations is
desirably selected to maximize the counteradaptation while keeping any direct
effects of
ligand binding during the first time period at a low and tolerable level.
According to one
embodiment of the invention, the ratio of the administration half-life to the
period between
administrations is no greater than 1/2. Desirably, the ratio of the
administration half-life to
the period between administrations is no greater than 1/3. In certain
embodiments of the
invention, the ratio of the administration half-life to the period between
administrations is
no greater than 115; no greater than 1/8; or no greater than 1/12. It may be,
however,
desirable to administer the ligand relatively often, in order to maintain a
desired level of
counteradaptation. For example, in certain desirable embodiments of the
invention the
ratio of administration half-life to the period between administrations may be
greater than
1/100; greater than 1/50; greater than 1/24; greater than 1/12; greater than
1/8; greater than
1/5; greater than 1/4; or greater than 1/3.
[0050] A substantial fraction of the receptors of the type of receptor are
desirably bound to
the ligand during the first time period associated with each administration,
so as to cause a
counteradaptation to the ligand binding. For example, at least about 30%, at
least about
50%, at least about 75%, or at least about 90% of the receptors of the type of
receptor are
desirably bound by the ligand during each first time period.
[0051] Similarly, the first time period associated with each administration is
desirably long
enough to cause a substantial counteradaptation. For example, each first time
period is
desirably at least about five minutes in duration; at least about thirty
minutes in duration; at
least about an hour in duration; at least about two hours in duration; or at
least about four
hours in duration. In certain desirable embodiments of the invention, each
first time period
is about eight hours in duration. However, in cases where the direct effect of
ligand
binding is a noticeable worsening in. an undesirable condition, it may be
desirable to
maintain the first time period no longer than necessary to get an acceptable
level of
13
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
counteradaptation. For example, in certain embodiments of the invention the
first time
period is desirably less than about twenty four hours in duration; less than
about sixteen
hours in duration; less than about twelve hours in duration; less than about
eight hours in
duration; or less than about six hours in duration.
[0052] In desired embodiments of the invention, a substantial fraction of the
receptors
remain unbound to the ligand during a second time period associated with each
administration and subsequent to the first time period. A low level of ligand-
receptor
binding allows the patient to enjoy the effects (e.g., the therapeutic
benefit) of the
counteradaptation without interference from any ill effects of direct ligand
binding. For
example, desirably no more than about 50%, no more than about 25%, no more
than about
10% of the receptors are bound to the ligand during each second time period.
[0053] The second time period associated with each administration is the time
during
which a substantial fraction of the receptors of the type of receptor are
unbound to the
ligand. During each second time period, the patient may enjoy any therapeutic
benefit of
the counteradaptation, as no direct Iigand-receptor binding effects would
remain. As such,
each second time period is desirably as long as possible. For example, each
second time
period is desirably at least about two hours in duration; at least about ten
hours in duration;
or at least about fifteen hours in duration. However, it may be desirable to
keep each
second time period relatively short, in order to decrease the period between
administrations
thereby increase the counteradaptation. For example, in certain embodiments of
the
invention each second time period is desirably no more than about twenty hours
in
duration; no more than about thirty hours in duration; or no more than about
fifty hours in
duration.
[0054] In order to build up a counteradaptation over time and to minimize any
initial
exacerbation of an undesirable mental, neurological or physiological
condition, it may be
desirable to begin the treatment with a relatively low dose of ligand at each
administration,
and increase the dosage over time. Increasing dosages can also be used to
account for any
tolerance the patient builds up to the ligand. For the sake of convenience, it
may be
desirable to increase the dosage intermittently over time (i.e., increase the
dosage with a
period longer than the period between administrations). For example, in
certain
embodiments of the invention the dosage is increased with a period between
increases of
no less than a week; no less than two weeks; no less than three weeks; no less
than a
14
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
month; no less than two months; no less than three months; no less than six
months, or no
less than one year. At each increase in dosage, the dose is desirably
increased by at least
about 5%; at least about 10%; at least about 25%; at least about 50%; or at
least about
100% of the initial dose. It may, however, be desirable to maintain the
maximum dosage
within certain limits. For example, in certain embodiments of the invention
the maximum
dosage may be within three hundred times the initial dosage, within one
hundred times the
initial dosage, within fifty times the initial dosage, or within twenty times
the initial
dosage.
[0055] In one example of a dosing schedule, low doses of a ligand are given
for one, two,
or three weeks. These initial doses are high enough to induce a
counteradaptive response,
but low enough to cause only minimal direct effects due to ligand-receptor
binding. The
dose is then increased. The increase may be as small as 10%; for more rapid
induction of a
counteradaptive response, however, it is desirable to at least double the
initial dose. After
four to six weeks the dosage is again increased. This pattern is followed
every one, two,
four or six months. The endpoint for the maximum dosage will depend on
individual
tolerance to the ligand and the development of side effects and direct effects
from the
larger doses.
[0056] To reduce the impact of any direct effects of ligand-receptor binding,
it may be
desirable to tinie the administration of the ligand so that the first time
period occurs during
a time when adverse effects on the patient will be minimized. The patient will
not notice
many of the direct effects of ligand-receptor binding (e.g., a decrease in
mood) if she is
asleep. For example, it may be desirable to time the administration of the
ligand so that a
substantial fraction of the first time period occurs while the patient is
asleep, so that any
direct effects of ligand-receptor binding are not noticed. For example, at
least 40%; at least
60%; or at least 85% of the first time period desirably occurs while the
patient is asleep. In
order to achieve such timing, it may be desirable to perform a substantial
fraction of the
administrations of the ligand within the hour before the patient goes to bed.
For example,
desirably at least 50%; at least 75%; at least 90%; or at least 95% of the
administrations of
the ligand are performed within the hour before the patient goes to bed.
[0057] There is no contraindication for daytime administration, however, and
in other
embodiments of the invention, each administration of the ligand is performed
more than
one hour before the patient goes to bed. In one example of a method according
to the
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
present invention, a patient who has been administered a ligand daily for two
or three
months and has developed a counteradaptation and, for example, some associated
improvement in mood. If there were a particular time of day the patient wanted
to enhance
daytime mood, the time of ligand administration could, be moved so that the
desired time
would fall within the second time period associated with that administration.
If the patient
wanted an elevated mood at 6 p.m., he could administer an appropriate ligand
(e.g.,
naloxone, a mu and/or delta opiate receptor antagonist with a compound half-
life of one
hour) at 2 p.m. The direct effect of naloxone-receptor binding (a bad mood)
would last
only a couple of hours, leaving only the good mood caused by the
counteradaptation by 6
p.m.
[0058] The administration of the ligand is desirably repeated enough times to
build up a
suitably large counteradaptive effect. As such, in the methods of the present
invention, the
administration is desirably performed at least five times, at least ten times,
at least twenty-
five times, or at least fifty times.
[0059] Each administration of the ligand may be performed orally,
transdermally, through
inhalation, subcutaneously, intravenously, intramuscularly, intraspinally,
intrathecally,
transmucosally, or using an osmotic pump, a microcapsule, an implant or a
suspension_
The skilled artisan will select the route of administration based upon the
identity of the
ligand, its compound half-life, the desired dose and the desired
administration half-life.
[0060] It may be desirable to administer the ligand using both a rapidly
absorbed loading
dose (in order to get a fast ligand-receptor binding), and a gradually
absorbed dose (in
order to maintain a desired level of ligand-receptor binding over the desired
length of the
first time period). A rectal suppository having a rapidly-absorbing outer
covering and a
more slowly absorbing center could be used for such an administration.
Alternatively, the
loading dose could be given sublingually, and the gradually absorbed dose
could be given
transdermally via patch.
[0061 ] A carrier in the blood may be used to increase the administration half-
life of the
ligand once it is in circulation. For example, U.S. Patents 6,610,825 and
6,602,981, each of
which is incorporated herein by reference in its entirety, describe a method
by which
ligands are bound to blood cells or proteins in order to extend their
administration half-life.
Adessi et al (Curr Med Chem, 9(9); May, 2002;963-978) describe a method by
which to
stabilize peptide ligands.
16
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0062] The methods of the present invention may be used to treat or address
any
undesirable condition linked to the neurotransmitter system. Examples of such
conditions
include chronic pain, mood disorders, eating disorders, anxiety disorders,
motivational and
performance problems, inflammatory conditions, nausea, emesis, urinary
incontinence,
skin rashes, erythema, eruptions, cardiovascular conditions, immune system-
related
conditions, and effects of aging. More examples of undesirable mental,
neurological or
physiological conditions are described below.
[0063] It may also be desirable to administer an anxiolytic agent in
combination with the
ligand, so as to reduce any direct effects of ligand-receptor binding. The
anxiolytic agent
may especially help mitigate the effects of ligand-receptor binding on the
patient's sleep.
The anxiolytic agent may, for example, affect a GABA pathway. The anxiolytic
agent may
be, for example, a benzodiazepine such as diazepam, lorazepam, alprazolam,
temazepam,
flurazepam, and chlodiazepoxide. Similarly, it may be desirable to administer
a hypnotic
agent or a selective serotonin reuptake inhibitor in combination with the
ligand, so as to
reduce any direct effects of ligand-receptor binding. Each of these agents may
be
administered at the same time as the ligand, or at a different time. It may
also be desirable
to add tryptophan to the patient's diet, as described in U.S. Patents
4,377,595 and
5,958,429, each of which is incorporated herein by reference in its entirety.
[0064] In some cases, one direct effect of ligand-receptor binding is a
decrease in immune
system function. Accordingly, it may be desirable to administer an autoimmune
medication in combination with the ligand during the first time period.
Examples of
suitable autoimmune therapy include medications such as corticosteroids,
chlorambucil,
cyclosporine, cyclophosphamide, methotrexatate, azathioprine, TNFa
antagonists, and
therapies such as systemic enzyme therapy, gene therapy and irradiation
therapy. Of
course, as the skilled artisan will realize, other autoimmune medications may
be used in the
methods of the present invention, including those developed in the future. In
certain
embodiments of the invention, autoimmune therapy is not administered during
the second
time period.
[0065] Similarly, it may be desirable to administer an antiviral agent in
combination with
the ligand during the first time period. Examples of suitable antiviral agents
include
interferon, ribavirin, protease inhibitors, amantadine, rimantadine,
pleconaril, antibodies
(monoclonal, anti-VAP, receptor anti-idiotypic, extraneous receptor and
synthetic receptor
17
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
mimics), acyclovir, zidovudine (AZT), lamivudine, RNAase H inhibitors,
integrase
inhibitors, attachment blockers of transcription factors to viral DNA, so-
called `antisense'
molecules, synthetic ribozymes, zanamivir, and osletamivir. Of course, as the
skilled
artisan will realize, other antiviral medications may be used in the methods
of the present
invention, including those developed in the future. In certain embodiments of
the
invention, the antiviral agent is not administered during the second time
period.
[0066] Similarly, it may be desirable to administer an antimicrobial agent, an
antifungal
agent, and/or an antineoplastic agent in combination with the ligand during
the first time
period. In certain embodiments of the invention, the antimicrobial agent, the
antifungal
agent, and/or the antineoplastic agent is not administered during the second
time period.
[0067] It may be desirable to administer an anti-cancer agent in combination
with the
ligand during.the first time period. Suitable anti-cancer agents include, for
example,
adriamycin, busulfan, carboplatin, chlorambucil, cisplatin, cyclophosphamide,
ifosfamide,
mechlorethamine, melphalan, procarbazine, temozolamide, daunorubicin,
doxorubicin,
idarubicin, bleomycin, mitomycin, mitoxantrone, plicamycin, cytarabine
fluorouracil,
hydroxyurea, methotrexate, asparaginase, pegaspargase, irinotecan, topotecan,
bicalutamide, estramustine, flutamide, leuprolide, megestrol, nilutamide,
testosterone,
triptorelin, anastrazole, letrozole, aldesieukin, alemtuzumab, gemtuzumab,
toremifene,
trastuzumab, etoposide, docetaxel, paclitaxel, vinblastine, vincristine,
vinorelbine,
altretamine, Erlotinib, gleevec, curcumin, tamoxifen, bortezomib, gefitinib,
imatinib,
cancer cell growth inhibitors derived from 3,4-rnethylenedioxy-5,4'-dimethoxy-
3'-amino-Z-
stilbene, hydroxyphenstatin and its sodium diphosphate prodrug, histone
deacetylase
inhibitors, suberoylanilide hydroxamic acid, trichostatin A, sodium butyrate,
metformin,
five-lipoxygenase (5-LO) antagonists, antisense oligonucleotides targeting the
RIa
regulatory subunit of protein kinase A type I, Vitamin E and its analogs,
vitamin E
succinate (VES), and gene therapy. Of course, as the skilled artisan will
realize, other
autoimmune medications may be used in the methods of the present invention,
including
those developed in the future. In certain embodiments of the invention, the
antiviral agent
is no,t administered during the second time period.
[0068] It may be desirable to administer conventional pharmaceutical agents in
combination (e.g., simultaneously or sequentially) with the ligand.
Administration of such
an agent is especially desirable when it is an agonist for a type of receptor
that has been
18
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
increased in number and/or sensitivity through a counteradaptation, or is an
antagonist for a
type of receptor that has been decreased in number and/or sensitivity through
a
counteradaptation. Examples of conventional pharmaceutical agents that may
administered
in combination with the ligand include TCAs, MAOIs, SSRIs, NRIs, SNRIs, CRF
modulating agents, serotonin pre-synaptic autoreceptor antagonists, 5HT1
agonist,dynorphin antagonists, GABA-A modulating agents, serotonin 5H2O and/or
5Hzu
modulating agents, beta-3 adrenoceptor agonists, NMDA antagonists, V 1 B
antagonists,
GPCR modulating agents, or substance P antagonists. Desirably, the additional
pharmaceutical agent has a relatively short administration half-life, so that
it can be
administered during the second time period, with its effect substantially
absent by the next
administration of the ligand. Such an administration regimen maintains a high
level of
counteradaptation, while maximizing the effect of the pharmaceutical agent
during the
second time period.
[0069] It may also be desirable to take advantage of direct binding of the
receptors to
provide a desired clinical effect. For example, when the ligand is a receptor
agonist, it may
be desirable to administer an antagonist for the type of receptor during one
or more of the
second time periods associated with each administration and subsequent to the
first time
period. However, the antagonist for the type of receptor is desirably not
administered
during the first time period associated with each administration. Similarly,
when the ligand
is a receptor antagonist, it may be desirable to administer an agonist for the
type of receptor
during one or more of the second time periods associated with each
administration and
subsequent to the first time period. However, the agonist for the type of
receptor is
desirably not administered during the first time period associated with each
administration.
Preferably the antagonist has an in vivo half life of less than 12 hours, less
than 8 hours, or
less than 6 hours, such that it would not interfere with the subsequent
administration of the
agonist.
[0070] Another embodiment of the present invention is illustrated by the
graphs of in vivo
ligand concentration (part a) and mood vs. time (part b) of FIG. 6. In this
method, a
counteradaptation is first induced by giving the patient one or more doses of
a ligand for
the type of receptor. As shown in FIG. 6, this could be through repeated or
continuous
administration of high doses of the ligand. Relatively high, long-term doses
of the ligand
will induce a strong counteradaptive effect, but may cause the patient to
suffer marked
direct effects from ligand-receptor binding, as shown in the graph of mood vs.
time of FIG.
19
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
6. In such cases, it may be desirable to keep the patient hospitalized during
the initial
induction of the counteradaptive response. After the counteradaptive response
is induced,
it is maintained repeatedly administering the ligand to the patient with a
ratio of
administration half-life to period between administrations no greater than
1/2. The
repeated administration may be performed substantially as described above.
[0071] Through regulation of the function of neurotransmitter systems, the
methods of the
present invention may be used to improve undesirable mental, neurological and
physiological conditions, even if they are not able to cure them. The methods
of the
present invention may make undesirable mental, neurological, and physiolocigal
conditions
more amenable to conventional therapies. For example, even if clinical
depression is not
cured, the improved mood caused by the use of the methods of the present
invention may
help improve the depression. As described above, the use of conventional
antidepressants
may also be made more efficacious. In another example, even if cancer is not
cured, the
regulation of the neurotransrnitter acts to suppress tumor growth andlor
metastasis, and
may make conventional cancer therapies and/or the immune system better able to
eliminate
the cancerous growth. The therapeutic benefits caused by the'regulation of the
neurotransmitter may be, for example, a decrease in the severity of the
symptoms
associated with the mental, neurological or physiological condition; an
eradication of the
symptoms associated with the mental, neurological or physiological condition;
or an
increase in a mood that masks the symptoms associated with the mental,
neurological or
physiological condition.
[0072] The methods according to the present invention may be used
therapeutically to
address undesirable mental, neurological or physiological conditions in a
patient. For
example, the methods of the present invention may be used to treat a pre-
existing
undesirable mental, neurological or physiological condition in a patient, such
as a mood
disorder, an eating disorder, a pain disorder, a substance abuse disorder, an
anxiety
disorder, or an obsessive-compulsive disorder. The methods may also be used to
reduce
any future undesirable mental, neurological or physiological condition that is
anticipated to
occur, for example, due to future physical exertion, physical trauma, mental
trauma, or
medical procedure. Many examples of conditions that may be addressed using the
methods
of the present invention are described in more detail below.
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
THE SUBSTANCE P SYSTEM
[0073] According to one embodiment of the invention, the neurotransmitter
system is the
Substance P("SP") system, which includes as neurotransmitters the neurokinins
Substance
P, NKA and NKB. SP is a polypeptide and is known to act as a neurotransmitter
and
mediator for pain sensations. It is a member of the tachykinin family, which
is a set of
polypeptides having a similar C-terminal and a varying N-terminals with
varying SP-like
activity. The SP receptors include NK-1, NK-2 and NK-3 receptors. SP
preferentially
binds to NK-1 receptors, NKA preferentially binds to NK-2 receptors, and NKB
preferentially binds to NK-3 receptors.
[0074] SP and its receptors are found primarily in the brain and spinal cord
tissue. In the
spinal cord, SP receptors are found in an area called the dorsal horn, which
is a primary site
for pain signals to be transmitted to the brain. In the brain, SP and its
receptors are found
in large concentrations in the hypothalamus and the amygdala, areas associated
with
affective behavior, anxiety and response to stress, and pain. In addition, SP
is also
implicated in nausea and emesis, defensive behavior, cardiovascular tone,
salivary
secretion, inflammation, smooth muscle contraction and vasodilation, as well
as in
numerous mental conditions such as schizophrenia, manic depressive psychosis,
sexual
dysfunction, drug addiction, cognitive disorders, locomotive disorders, and
depression.
[0075] When the neurotransmitter system is the SP system, the type of receptor
is SP
receptors, which are positively linked to many undesirable mental and
neurological
conditions, and the ligand is an SP receptor agonist. The counteradaptation
causes a down-
regulation of the SP system, and may be at least one of a decrease in the
biosynthesis or
release of SP, NKA and/or NKB at the receptor terminals or by the pituitary
gland; a
decrease in the number of the receptors and/or binding sites on the receptors;
or a decrease
in the sensitivity of the receptors to binding by SP receptor agonists and/or
SP, NKA and/or
NKB.
[0076] The SP receptor agonist may be, for example, peptide-based. In certain
embodiments of the invention, the SP receptor agonist is an analogue of SP,
NKA, and/or
NKB, or a pharmaceutically acceptable salt or derivative thereof. For example,
the SP
receptor agonist may be Substance P; Substance P, free acid; Biotin-Substance
P; [Cys3'6,
Tyr$, Pro9]-Substance P; (Disulfide bridge: 3-6), [Cys3 6, Tyrg, Pro10]-
Substance P;
(Disulfide bridge: 3-6), [4-Chloro-Phe7'$]-Substance P; [4-Benzoyl-Phe8]-
Substance P;
21
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[Succinyl-Asp6,1V-Me-Phe8]-Substance P (6-1 1)(Senktide); [Tyrg]-Substance P;
[Tyr9]-
Substance P; Shark Substance P Peptide; GR73632 [D-Ala-[L-Pro9,Me-
Leug]substance P(7-
11)]; [Sar9,Met(02)"]SP; GR 73,632 [delta-Aminovaleryl [Pro9, N-Me-Leu10]-
substance
P(7-11)], [Glu(OBzl) I 1]substance P and hemokinin I(HK-1) (a substance P
homolog); or
a pharmaceutically acceptable salt or carrier thereof.
[0077] In other embodiments of the invention, the SP receptor agonist may be
an NKA or
NKB analogue having a C-terminal heptapetpide similar to NKA(4-10) or NKB(4-
10), or a
pharmaceutically acceptable salt or carrier thereof. For example, the SP
receptor agonist
may be [Gln4]-NKA, [GIn4]-NKA(4-10), [Pbe7]-NKA, [Phe7]-NKA(4-10), [IIe7]-NKA,
[Ile7]-NKA(4-10), [LysS,MeLeu9,Nle10]-NKA(4-10), [Nle10]-NKA(4-10), (3-Ala$]-
NKA(4-
10), [Alas]-NKA(4-10), * [G1n4]-NKB, [Gln4]-NKB(4-10), [Phe7]-NKB, [Phe7]-
NKB(4-
10), [I1e7]-NKB, [Ile7]-NKB(4-10), [Lys5,MeLeu9,Nlei0]-NKB(4-10), [N1e10]-
NKB(4-10),
[i-AlaB]-NKB(4-10), [Ala5]-NKB(4-10), or a pharmaceutically acceptable salt or
carrier
thereof. Similarly, the SP receptor agonist may be [Arg]-NKB, an NKA or NKB
analogue
having Val7 replaced with MePhe, or a pharmaceutically accepted salt or
carrier thereof.
[0078] Other SP receptor agonists that may be used in the present.invention
are SR 48968,
an NK2 receptor antagonist ((S)-N-methyl-N [4-(4-acetylamino-4-[(phenyl
piperidino)-2-
(3,4-dichlorophenyl)-butyl] benzamide]) as well as those described in U.S.
Patents
4,839,465; 4,472,305; 5,137,873; 4,638,046; 4,680,283; 5,166,136; 5,410,019;
and
6,642,233, each of which is incorporated herein by reference in its entirety.
[0079] The initial dosage (i.e., the dosage at the first administration) of
the SP receptor
agonist is desirably high enough to induce a counteradaptive effect, but not
so high as to
cause intolerable direct effects from ligand-receptor binding. For example,
the initial
dosage of the SP receptor agonist may be between about 0.5 pmol/kg/min and
about 20
pmol/kg/min for continuous dosing during the first time period. In certain
desirable
embodiments of the invention, the initial dosage of the SP receptor agonist is
between 3
pmol/kg/min and 10 pmol/kg/min for continuous dosing during the first time
period.
[0080] The present invention is not limited to the use of peptide-based SP
receptor
agonists. Other SP receptor agonists, including substantially or wholly non-
peptidic SP
receptor agonists (e.g., those described in Chorev et al., Biopolymers, May
1991;
31(6):725-33), which is hereby incorporated herein by reference in its
entirety) may be
used in the methods of the present invention.
22
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0081] The SP receptor agonist may be administered using any appropriate
route.
Transmucosal administration is an especially desirable method for
administering SP
receptor agonists. For example, the administration may be sublingual or via
rectal
suppository. It may be desirable to administer the SP receptor agonist using
both a rapidly
absorbed loading dose (in order to get a fast binding of the SP receptors),
and a gradually
absorbed dose (in order to maintain a desired level of agonist-receptor
binding over the
desired length of the first time period). A rectal suppository having a
rapidly-absorbing
outer covering and a more slowly absorbing center could be used for such an
administration. Alternatively, the loading dose could be given sublingually,
and the
gradually absorbed dose could be given transdermally via patch. Other routes
include
intraspinal or intrathecal administration for pain.
[0082] Desirably, an SP receptor antagonist is not administered during the
first time period
associated with each administration. In certain embodiments of the invention,
however, an
SP receptor antagonist is administered during one or more of the second time
periods.
Non-limiting examples of SP receptor antagonists along with suggested dosages
are as
follows: SR 48968 ((S) N methyl N(4-acetylamino-4-phenylpiperidino-2-(3,4-
dichloophenyl)butyl)benzamide); Osanetant and compounds described in US
5,972,938; 6,
576, 638; 6,596,692; 6,509,014; 6,642,240; 6,841,551; 6,177,450; 6,518,295; US
6,369,074; AND US 6,586,432; AND WO 95/16679; 95/18124; 95/23798.
[0083] Other SP (NKI) receptor antagonists include: L-760735 ([1-(5-{[(2R,35')-
2-({(1R)-
1-[3,5-bis(trifluoromethyl)phenyl]ethyI} oxy)-3-(4-phenyl)morpholin-4-
yl]methyl} -2H-
1,2,3-triazol-4-yl)-N,N-dimethylmethanamine]) (See Boyce, S, et al.
Neuropharmacology.
2001 Ju1;41(1):130-7); CP-96,345 [(2S,3S)-cis-2-(diphenylmethyl)-N-[(2-methoxy-
phenyl)-methyl]-1- azabicyclo [2.2.2]-octan-3-amine] (See Snider, et al,
Science, 1991 Jan
25; 251(4992):435-7); SSR240600 ([(R)-2-(1-{2-[4-{2-[3,5-
bis(trifluoromethyl)phenyl]acetyl} -2-(3,4-dichlorophenyl)-2-
morpholinyl]ethyl} -4-
piperidinyl)-2-methylpropanamide] (See Steinberg, R. et al., Steinberg, R, et
al, J Pharm
Exper Ther, 303(3), 1180-1188, December 2002, "SSR240600 [(R)-2-(1-{2-[4-{2-
[3,5-
Bis(trifluoromethyl)phenyl]acetyl}-2-(3,4-dichlorophenyl)-2-morpholinyl]ethyl
} -4-
piperidinyl)-2-methylpropanamide], a Centrally Active Nonpeptide Antagonist of
the
Tachykinin Neurokinin I Receptor: II. Neurochemical and Behavioral
Characterization");
NKP608 [quinoline-4-carboxylic acid [trans-(2R,4S)-1-(3,5-bis-trifluoromethyl-
benzoyl)-
2-(4-chloro-benzyl)-piperidin-4-yl]-amide)] (see Spooren WP, et al., Eur J
Pharmacol.
23
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
2002 Jan 25;435(2-3):161-70 and File, SE, Psychopharmacology (Berl). 2000
Sep;152(1):105-9, entitled "NK.P608, an NK1 receptor antagonist, has an
anxiolytic action
in the social interaction test in rats."); L-AT (N-acetyl-L-tryptophan 3,5-bis
benzyl ester)
(See Crissman, A, et al., Vol. 302, Issue 2, 606-611, August 2002, entitled
"Effects of
Antidepressants in Rats Trained to Discriminate Centrally Administered
Isoproterenol");
MK-869 [Aprepitant) (SeeVarty, GB, et al., Neuropsychopharmacology (2002) 27
371-
379, "The Gerbil Elevated Plus-maze II: Anxiolytic-like Effects of Selective
Neurokinin
NK1 Receptor Antagonists"); L-742,694 [2(S)-((3,5-bis(Trifluoromethyl)benzyl)-
oxy)-
3(S)phenyl-4-((3-oxo-1,2,4-triazol-5-yl)methyl)morpholine] (See Varty, et
al.); L-733060
[(2S,3S)3-([3,5-bis(trifluoromethyl)phenyl]methoxy)-2-phenylpiperidine] (See
Varty, et
al.); CP-99,994 [(+)-(2S,3S)-3-(2-methoxybenzylamino)-2-phenylpiperidine] (See
McLean, et al, J Pharm Exp Ther, Volume 267, Issue 1, pp. 472-479 and Varty,
et al.); CP-
122,721 [(+)-(25,3 S)-3-(2-methoxy-5-trifluoromethoxybenzyl)amino-2 -
phenylpiperidine]
(See McLean, et al., J Pharm ExpTher, Volume 277, Issue 2, pp. 900-908 and
Varty, et al);
CP-96,345 [(2S,3S)-cis-2-(diphenylmethyl)-N-((2-methoxyphenyl)-methyl)-1-
azabicyclo(2.2.2.)=octan-3-amine] (see Bang, et al., J Pharmacol Exp Ther.
2003 Apr;
305(l):31-9); GSK 597599 [Vestipitant]; GSK 679769 (See Hunter et al. U.S.
Patent
Publication no. 20050186245); GSK 823296 (See Hunter et al. U.S. Patent
Publication no.
20050186245); Saredutant (See Van Schoor, et al., Eur Respir J 1998; 12: 17-
23;
Talnetant; Osanetant (see Kamali, F, Curr Opin Investig Drugs. 2001
Jul;2(7):950-6); SR-
489686 (benzamide, N-[4-[4-(acetylamino)-4-phenyl-l-piperidinyl]-2-(3,4-
dichloro-
phenyl)butyl]-N-methyl-(S)-); SB-223412 (See Hunter et al. U.S. Patent
Publication no.
20050186245); SB-235375 (4-quinolinecarboxamide-, 3-hydroxy-2-phenyl-N-[(1 S)-
1-
phenylpropyl]-), UK-226471 (See Hunter et al. U.S. Patent Publication no.
20050186245).
[0084] Suitable but non-limiting initial dosages for SP receptor antagonists
include about
12 mg/kg/hour/administration for 8 hours of L-760735 (via iv); about 30
glkg/hour/administration for 8 hours of CP-96,345 (via iv); about 0.1 and 10
mg/kg/administration of SSR240600 (via ip or po); about 0.01 to 0.1
mg/kg/administration
of NKP608 (via po); about I to 10 mg/kg/administration of L-AT; about 0.01 to
3
mg/kg/administration of MK-869; about 1 to 30 mg/kg of L-742,694; about 1 to
10
mg/kg/administration of L-733,060; about 3 to 30 mg/kg/administration of CP-
99,994 or
CP-122,721; and about 100 mg/administration of Saredutant (via po).
24
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0085] The SP neurotransmitter system is positively linked to a wide variety
of undesirable
mental and neurological conditions. Examples of such conditions include
chronic pain,
mood disorders, eating disorders, anxiety disorders, motivational problems,
substance
abuse disorders, inflammatory conditions, nausea or emesis (e.g., arising from
chemotherapy), urinary incontinence, skin rashes, erythema, eruptions,
fibromyalgia,
chronic fatigue syndrome, chronic back pain, chronic headaches, chronic cancer
pain,
shingles, reflex sympathetic dystrophy, neuropathy, inflammatory pain, pain
that is
anticipated to occur in the future (e.g., from a medical procedure or physical
exertion),
major depressive disorders, post-traumatic depression, temporary depressed
mood, manic-
depressive disorder, dysthymic disorder, generalized mood disorder, anhedonia,
non-
organic sexual dysfunction, overeating, obesity, anorexia, bulimia,
generalized anxiety
state, panic disorders, phobias, obsessive-compulsive disorder, attention
deficit
hyperactivity disorder, Tourette's Syndrome, hysteria sleep disorders,
breathing-related
sleep disorders, a lack of motivation due to learning or memory problems,
abuse of
substances such as narcotics, alcohol, nicotine, stimulants, anxiolytics, CNS
depressants,
hallucinogens and marijuana, asthma, arthritis, rhinitis, conjunctivitis,
inflammatory bowel
disease, inflammation of the skin or mucosa, acute pancreatitis. The down-
regulation of
the SP system desirably causes a therapeutic benefit with respect to the
undesirable mental,
neurological or physiological condition.
[0086] Virtually all types of pain, with the exception of acute sharp pain,
are associated
with the SP system. SP is not involved with the initial pain that is caused by
a stabbing
wound. The pain that lingers afterwards, however, is due to the SP pathway. In
a similar
manner the pain that lingers for a period of time after a surgical procedure
is mediated by
the SP pathway.
[0087) Mood is mediated through the SP system. Increased levels of SP are
found in
clinically depressed patients. Substance abusers have elevated levels of SP
and, for those
times when they are not on the abused substance, generally have a depressed
and/or
dysphoric mood. Clinical depression and substance abuse are thus both
associated with an
up regulation of the SP system. The pleasurable experiences of morphine are
absent in
mice that lack the SP receptor. Such mice do not become addicted to morphine
(Murtra, et
al., Nature 405, 180-183, May 11, 2000). Because opiates alone cannot induce
euphoria,
the Murtra study suggests that the SP system is the final pathway by which
opiate euphoria
is mediated. The fact that SP antagonists can acutely improve mood is
consistent with this
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
finding. Anxiety, response to stress, sexual dysfunction and eating disorders
are largely
related to mood, and are therefore also affected by the SP system.
[0088] The SP system has also been implicated in asthma (Kudlacz E.M.,
"Combined
tachykinin receptor antagonists for the treatment of respiratory diseases",
Expert Opinion
on Investigational Drugs, Vol. 7, No.7, July 1998, pp. 1055-1062)
nausea/emesis,
cancerous tumor growth and metastasis (Palma, C, et al., Br. J. Cancer, 1999
Jan; Vol.
79(2): 236-43 and Friess, et al., Lab. Invest. 2003 May; Vol. 83(5):731-42),
and urinary
incontinence (AnderssonKE, Experimental Physiology, Vol. 84(1), 195-213).
[0089] Methods of the present invention using SP receptor agonists as ligands
may be used
to address undesirable mental, neurological or physiological conditions in
patients. For
example the methods of the present embodiment of the invention may be used to
address
any of the above-listed conditions. The methods according to the present
embodiment of
the invention may also be used as an adjunct treatment for cancer (e.g., to
decrease tumor
growth and metastasis).
[0090] The methods of the present invention could also be used with an SP
agonist in
chronic recurring pain situations such as migraine headaches. Similarly,
because the SP
system is up-regulated in chronic pain syndromes, they may also be treated
using the
methods of the present invention with an SP agonist. Such chronic pain
syndromes include
pain due to nerve injury, neuropathies, chronic low back pain, reflex
sympathetic
dystrophy, cancer pain, shingles and arthritis.
[0091] The methods of the present invention can be used with SP agonists in
the
prophylaxis of pain prior to an event that is associated with pain. The
methods of the
present invention may be used in order to decrease post-operative pain and
also to increase
post-operative response to narcotic pain medications, which results in a lower
dose of
narcotics to obtain an analgesic effect. Similarly, an SP agonist could be
used in the
methods of the present invention prior to such pain-inducing competitive
events such as
football, hockey, and boxing. An SP agonist could be used prior to any
competitive event,
such as long distance running in order to reduce pain perceptions that are
inevitable with
such muscle and leg overuse activities. A reduced pain response ultimately
allows the
athlete to push him/her self to a greater extent, resulting in an improved
performance.
26
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0092] The methods of the present invention may also be used with SP agonists
in order to
address anxiety, stress response, sexual dysfunction and eating disorders may
be improved
with the SP agonist CAT protocol. These conditions are largely related to
mood, thus an
improvement in conditions such as these are indirectly related to overall mood
as opposed
to a direct effect.
[0093] The methods of the present invention may also be used with SP agonists
in order to
address any or all addictive disorders. For example, the methods of the
present invention
can be used to address the abuse of substances such as narcotics, alcohol,
nicotine/
cigarettes, stimulants, anxiolytics, CNS depressants, hallucinogens and
marijuana.
Furtherxnore, gambling and electronic gaming addictions follow the same brain
abnormalities as do substance abuse problems, and can also be addressed using
the
methods of the present invention.
[0094] The methods of the present invention may also be used with SP agonists
in order to
address asthma by decreasing the severity of asthma attacks. An inhalational
route of
administration may be used in order to concentrate the counteradaptive effect
in the lungs
where it is most needed. The methods of the present invention may also be used
with SP
agonists in order to decrease the inflammatory response in any one of a number
of
inflammatory conditions such as arthritis, rhinitis, conjunctivitis,
inflammatory bowel
disease, inflammation of the skin and mucosa and acute pancreatitis. The
methods of the
present invention may also be used with SP agonists in order to address
nausea/emesis,
especially that associated with chemotherapy for cancer, and urinary
incontinence.
THE ENDOGENOUS ENDORPHIN SYSTEM
[0095] According to another embodiment of the invention, the neurotransmitter
system is
the endogenous endorphin system, which includes as neurotransmitters the
endorphins that
bind preferentially to mu and/or delta opiate receptors. Endorphins are
endogenous opiate-
like compounds that act through their effects on the binding of opiate
receptors. Mu and
delta opiate receptors act in unison, and are stimulated by opiate and opiate-
like
compounds. Mu receptors primarily modulate pain, but also modulate mood. Delta
receptors have the opposite focus, primarily modulating mood, but also
modulating pain.
[0096] When the neurotransmitter is the endogenous endorphin system, the type
of
receptor is mu and/or delta opiate receptors, which are generally negatively
linked to
27
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
undesirable mental and neurological conditions. Mu opiate receptors are
associated
primarily with lower levels of pain when stimulated, while delta opiate
receptors are
associated primarily with euphoria when stimulated: The ligand is a mu and/or
delta opiate
receptor antagonist, and the counteradaptation causes an up-regulation of the
endogenous
endorphin system. The counteradaptation may be, for example, an increase in
the
biosynthesis or release of endorphins at receptor terminals and/or by the
pituitary gland; an
increase in the number of the receptors and/or endorphin binding sites on the
receptors; an
increase in the sensitivity of the receptors to binding by mu and/or delta
receptor agonists
and/or endorphins; or any combination thereof.
[0097] The method according to the present embodiment of the invention may be
practiced
using a specific mu receptor antagonist or a specific delta receptor
antagonist. For
example, the method may be practiced using a specific mu receptor antagonist
such as
clocinnamox mesylate, CTAP, CTOP, etonitazenyl isothiocyanate, (3-
funaltrexarnine
hydrochloride, naloxonazine dihydrochloride, Cyprodime, and pharmaceutically
acceptable
salts, analogues, and derivatives thereof. The method may also be practiced
using specific
delta receptor antagonists such as naltrindole, N-benzylnaltrindole HCI, BNTX
maleate,
BNTX, ICI-154,129, ICI-174,864 (N,N-diallyl-Tyr-Aib-Aib-Phe-Leu-OH, where Aib
is
alpha-amino-isobutyric acid), naltriben mesylate, SDM25N HCI, 7-
benzylidenenaltrexone,
and phannaceutically acceptable salts, analogues, and derivatives thereof. The
skilled
artisan may also employ non-specific mu and/or opiate antagonists, such as
naloxone and
naltrexone, in the methods according to the present embodiment of the
invention. Non-
limiting representative examples of non-specific opiate antagonists include
Nalorphine,
nalbuphine, levallorphin, cyclazocine, diprenorphine
[0098] Other mu and/or delta opiate receptor antagonists useable in the
methods of the
present invention include those described in U.S. Patents 5,922,887;
4,518,711; 5,332,818;
6,790,854; 6,770,654; 6,696,457; 6,552,036; 6,514,975; 6,436,959; 6,306,876;
6,271,239; -
6,262,104; 5,552,404; 5,574,159; 5,658,908; 5,681,830; 5,464,841; 5,631,263;
5,602.099;
5,411,965; 5,352,680; 5,332,818; 4,910,152; 4,816,586; 4,518,711; 5,872,097;
5,821,219;
5,326,751; 4,421,744; 4,464,358; 4,474,767; 4,476,117; 4,468,383; 6,825,205;
6,455,536;
6,740,659; 6,713,488; 6,838,580; 6,337,319; 5,965,701; 6,303,578; and
4,684,620, and
International Patent Application WO/2004/026819 each of which is incorporated
herein by
reference in its entirety.
28
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[0099] In certain desirable embodiments of the invention, the mu and/or delta
opiate
receptor antagonist is naloxone, naltrexone, nalmefene, or nalbuphine, or a
pharmaceutically acceptable salt or derivative thereof. Naltrexone is a
desirable mu and/or
delta receptor antagonist, but may not be usable in all situations due to its
long compound
half-life (48-72 hours); while naltrexone itself has a half-life of 9-10
hours, its active
metabolites (e.g. 6-beta-naltrexol and 2-hydroxy-3-methoxynaltrexol) have much
longer
half-lives. Naloxone is an especially desirable mu and/or delta receptor
antagonist for use
in the present embodiment of the invention. Naloxone has a compound half-life
of about
an hour, but cannot be given orally. Naloxone can be given intravenously or
through a
transdermal patch, desirably using a time-release formulation. Suitable
transdermal
patches are described in U.S. Patent 4,573,995, which is hereby incorporated
herein by
reference in its entirety. ,
[00100] Naloxone has a half-life of 1-1.5 hours, which is favorable for use in
the
methods of the present invention. Although the 1-1.5 hour half-life is
adequate for
inducing a counteradaptive response, amore preferred ligand for use in the
present
invention would have a half-life between 2-4 hours. Furthermore, naloxone has
very poor
oral bioavailability, being only 5%, making it less convenient for outpatient
administration.
[00101] Thus in one aspect, the present invention provides methods using 3-
hydroxymorphinans and derivatives and prodrugs thereof as mu and/or delta
opiate
antagonist ligands that are orally bioavailable, and that have a half=life
that is longer than
that of native naloxone, yet less than the 8 hour half-life of naltrexone or
nalmefene. The
preferable compounds have half-lives that are 4 hours or less, and are
desirably in the range
of 2-4 hours. Optionally, the 3-hydroxymorphinans as mu and/or delta opiate
antagonist
ligands may be given by a transmucosal route.
[00102] The bioavailablity of 3-hydroxymorphinan compounds may be increased
through the use of prodrug formulations. The pro-drug formulations for the
invention
herein involve the attachment of a chemical group(s) to the native 3-
hydroxymorphinan
compound in order to prevent the first pass metabolism process, which is the
rapid
glucuronidation of the 3-OH moiety. The attached chemical groups for the
invention
herein are non-toxic. Furthermore, the attached chemical groups are those that
are
removed in a period of time such that the overall compound half-life of the mu
and/or delta
opiate antagonist ligand remains less than 4 hours.
29
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00103] Some of the 3-hydroxymorphinan compounds described herein for use in
the present invention have enhanced lipophilicity. Greater lipophilicity
enhances
transmembrane absorption, which acts to improve oral and transmucosal
bioavailability. It
further results in a more rapid and efficient transport across the blood-brain
barrier. Such
improved transport across the blood-brain barrier is preferable in that it
results in a greater
counteradaptive response by the mu and/or delta opiate receptor antagonist.
[00104] In desirable embodiments of the invention, the mu and/or delta opiate
receptor antagonist is a naloxone analog, due to the fact that naloxone
analogs have a
relatively shorter half-life than do other opiate antagonists, such as
naltrexone or
nalmefene.
[00105] In order to make naloxone orally, and/ or transmucosally, bioavailable
for
outpatient (or inpatient) counteradaptive therapy purposes, numerous naloxone
pro-drug
chemical formulations are desirably used. These pro-drugs include
modifications at the 3-
OH moiety, the 6-Carbon, the C-14 Carbon and N-oxide pro-drug formulations.
The
preferred modifications are at the 3-OH and/or the 6-Carbon sites.
3-OH Modifzeations
[00106] Morphine example:
[00107] Morphine analogs are used in order to demonstrate modifications that
result
in a more lipophilic structure and how such modifications are beneficial. The
morphine
structure is:
HO
Me
0
H
HO
[00108] When the 3-OH and 6-OH groups are converted to acetyl groups, the
compound becomes diacetylmorphine, which is otherwise known as heroin.
Diacetylmorphine has properties that are favorable to morphine in that it is
more lipophilic,
therefore it is more rapidly and efficiently absorbed across mucosal surfaces.
For example,
oral bioavailability of morphine is @ 25-30% (Hasselstrom, J, et al., Clin
Pharmacokinet.
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
1993 Apr;24(4): 344-54 and Gourlay, GK, et a]., Pain. 1986 Jun;25(3): 297-
312.), whereas
oral bioavailbility of diacetylmorphine is @ 67% (Girardin, F, et al.,
"Pharmacokinetics of
high doses of intramuscular and oral heroin in narcotic addicts." Clin
Pharmacol Ther.
2003 Oct;74(4): 341-52.) Furthermore, the diacetyl derivative more readily
crosses the
blood-brain barrier.
[00109] For the naloxone compound a similar lipophilicity occurs when the 3-OH
group is converted to the 3-acetylnaloxone derivative. This enhanced
lipophilicity results
in significant benefits over the native naloxone compound, including an
improved
bioavailability, enhanced potency and increased duration of action for 3-
acetyl naloxone.
These benefits are demonstrated by Linder and Fishman ("Narcotic Antagonists.
1. ..." J
Medicinal Chemistry, 1973, 16(5): 553).
[00110] When the carbon chain is further lengthened, such as converting the 3-
OH
to 3-propanoyl, 3-butanoyl, 3-hexanoyl then the lipophilicity is further
increased. For
example, with respect to the 3,5 diesters of morphine, the addition of such
lengthened
carbon chain groups results in either similar or greater potencies, along with
a longer
duration of action, from 20%, up to 5 times as long. [Owen, JA, et al.,
"Morphine Diesters.
I..." Can J Physiol Pharmacol. 1984 Apr;62(4): 446-51 and "Morphine Diesters.
II..."
pgs 452-456.]
[00111] Pesirable compounds for use in the present invention include similar 3-
OH
acetyl, butanoyl, propanoyl, hexanoyl derivatives of naloxone in order to
improve
lipophilicity (which acts to enhance the counteradaptive response), to improve
oral
bioavailability, and to slightly increase the duration of action of the
naloxone compound.
[00112] Naltrexone example:
[00113] Naltrexone is similar to the naloxone structure, the only difference
being the
N moiety. These differences are noted in the following sketches:
H Z Ho I
O O
OH OH
- 7 --
[00114] 0 0
Naloxone Naltrexone
31
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00115] Enhanced oral bioavailability of 3-hydroxymorphinans can be
demonstrated
by analyzing 3-OH modifications of the compound naltrexone. Specifically, 3-OH
modifications of the naltrexone compound, which consist of a benzoate analog
ester,
demonstrate enhanced bioavailability. For example, bioavailability is 28 to 45
times
greater for the acetylsalicylate and anthranilate esters of naltrexone,
respectively, as
compared to the native naltrexone compound. (see Hussain, MA, et al., J Pharm
Sci. 1987
May;76(5): 356-8; Hussain MA, et al., Pharm Res. 1988 Feb 5(2): 113-5; US
4,668,685
and US 4,673,679) The metabolic byproducts of these prodrugs of naltrexone are
anthranilic acid and acetylsalicylate. Anthranilic acid is a normal-occurring
metabolic
byproduct of the amino acid tryptophan. Acetylsalicylic acid is better known
as aspirin.
Both of these byproducts are considered safe and non-toxic at the doses that
would be
required to induce counteradaptations.
[00116] Accordingly, in desirable embodiments of the invention, such
anthranilic
acid acetylsalicylic acid 3-OH prodrug modified naloxone compounds are used in
the
methods described herein. Furthermore, based on the increased lipophilicity
and improved
oral bioavailability of the carbonyl attachments at the 3-OH site, in other
desirable
embodiments of the invention alkanoyl (2-6 carbon atoms) prodrug modified
naloxone
compounds are used in the methods described herein.
Carbon-6 Modifications
[00117] In certain desirable embodiments of the invention, the methods
described
herein are performed using naloxone derivatives modified at the 6-carbon. One
such
modification involves the conversion of the native 6- =O compound to its 6-
desoxy, 6-
methylene derivative (6- =CHz), as described, for example, in US 3,814,768 and
US
4,535,157.
[00118] The 6-methylene modification is a preferred one because such a
conversion
results in several benefits. These include enhancing the effects at the opiate
receptor,
improving oral bioavailability and making the molecule more lipophilic. These
benefits
are demonstrated when the 6- =CH2 substitution is made to the naltrexone
molecule, which
results in the compound that is called nalmefene. The 6-methylene naltrexone
analogue,
nalmefene, has improved properites over naltrexone for several reasons,
including: 1)
greater bioavailability, 2) longer duration of antagonist action, 3) more
competitive binding
to opioid receptor [which would generate a greater counteradaptive response],
and 4) no
32
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
dose dependent liver toxicity. [Mason, BJ, et al., Arch Gen Psych 1999, Aug;
56(8):719-24
and Dixon, R, et al., J Clin Pharrn 1987; 27:233-239.]
[00119] A further example of improved receptor activity with the 6- =CH2
substitution is demonstrated by the 6-methylene derivatives of morphine. Such
analogs are
75 times more potent than the parent morphine compound (see Hahn and Fishman,
J Med
Chem. 1975, 18(3): 259.). Hahn and Fishman further indicate that the 6-
methylene
naloxone derivative has considerably superior oral potency as compared to the
native
naloxone compound.
[00120] Another such modification involves the conversion of the native 6- =0
compound to its 6-desoxy (ie., 6- (-H)2) analog. The 6-desoxy modification has
several
potential benefits over the 6- =0 group. First, it makes the compound more
lipophilic.
Second, it increases opiate receptor activity. For example, 6-desoxymorphine
has 10 times
the activity as does the native morphine compound. Similarily, 6-desoxy
naloxone has
enhanced antagonist activity as compared to the native naloxone compound (see
Table 1,
Materials & Methods, Minakami, et al., Life Sciences 1962, 10; 503-507.).
Third, it is
intended to increase the duration of activity, ie., increase the half-life, to
a slight extent.
[00121] Other such modifications involve the conversion of the native 6- =0
compound to 6-OH, 6-amine, or 6-amide analogs. US 6,713,488 describes `Neutral
antagonists' where modifications are made at the 6-Carbon group. These
compounds are
said to be `neutral' because the 6 Carbon ketone group is converted to an -OH
functionality, or an amine, or amide or the like.
[00122] Simultaneous modifications may be made at both, the 3-OH and 6- C=0
sites. Such double modifications are intended to even further enhance oral
bioavailability
and the counteradaptive response. For example, because an anthranilic acid 3-
OH
substitution enhances oral bioavaiability 45 times, and because converting 6-
C=O group
into either a 6-methylene or 6-desoxy moiety also enhances oral
bioavailability, the two (3-
OH and 6C modifications) together are expected to enhance oral availability
even more.
Moreover, the two substitutions further act to improve transport across the
blood-brain
barrier and enhance opiate receptor activity, which both act to enhance the
counteradaptive
response, thus improving clinical efficacy.
33
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
Other Modifications
[00123] N-oxide derivatives of 3-hydroxymorphinans may also be used in the
methods of the present invention. Such derivatives are described in US
4,722,928 and
4,990,617.
[00124] Derivatives of hydroxymorphinans having substitution at the 14-Carbon
may also be used in the methods of the present invention. US 4,912,114 and US
4,272,540,
which are incorporated herein by reference, describe 3-hydroxymorphinan
compounds with
substitutions at the 14-Carbon group.
[00125] Accordingly, in certain embodiments of the invention, the mu and/or
delta
opiate receptor antagonist is a 3-morphinan compound having the structure
R10
I ~ .
O
2b R3~
R
R2a
wherein R is allyl, methylallyl, cyclopropylmethyl, dimethylallyl,
tetrahodrofiirfuryl or
cyclobutylmethyl; R' is H, (Ci-Cls hydrocarbyl)-, (CI-CI$ hydrocarbyl)-CO-,
(Cl-Ci$
hydrocarbyl)2N-CO-, (CI-C18 hydrocarbyl)-S02-, (Cl-CiS hydrocarbyl)-O-CO-, Ph-
CO-, Ph-
SO2-, Ph-NH-CO, wherein each Ph is optionally substituted with one or more
substituents
independently selected from the group consisting of (Cl-Cl2 hydrocarbyl), (CI-
Q2
hydrocarbyl)-0-, Cl, F, Br, I, CF3, R40-, and R42N-, in which each R4 is
independently
selected from the group consisting of H, (CI-C4 alkyl), H-CO- and (CI-C4
alkyl)-CO-; each
RZa and R2b is independently selected from the group consisting of H, (C1-C6
alkyl), (CI -C6
alkyl)-O-, (CI-C6 alkyl)-CO-O-, RS-O-, RSZN-, RS-CO-NH-, RS-S-, and NO2, in
which each
RS is independently selected from the group consisting of H, (CI-C6 alkyl),
(C3-CIo
cycloalkyl), (C6-Cro aryl), (Ct-C6 alkyl)-CO-, (C3-Clo cycloalkyl)-CO-, (C6-
CIo aryl)-CO-,
each of which is optionally substituted with 1-3 substituents selected from
the group
consisting of (Ci-C12 hydrocarbyl), (Ci-CI2 hydrocarbyl)-0-, Cl, F, Br, I,
CF3, R40-, and
R42N-; or R' and RZb together form O= or CH2=; and R3 is H, OH, CH3 or OCH3a
or an N-
oxide or pharmaceutically acceptable salt thereof. These compounds are
described in more
34
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
detail in U.S. Provisional Patent Application serial number 60/858,186,
entitled "OPIATE
ANATOGONISTS FOR COUNTERADAPTATION THERAPY," which is incorporated
herein by reference.
[00126] The compounds having the above-described structure may be desirable as
they can be formulated to have a compound half life of 2-4 hours, longer than
that of
naloxone, but shorter than that of naltrexone. Further, substitution at the 3-
OH (i.e.,
compounds with R' not H) can give the compounds greater oral bioavailablity
than
naloxone due to blocking of metabolic reactions at the 3-OH. Accordingly,
these
compounds may be formulated in more convenient oral administration forms. The
R'
moiety is preferably non-toxic when it is cleaved from the 3-OH to form its
corresponding
alcohol, acid or amide. The compounds may also be formulated to have greater
lipophilicity, which can enhance transmembrane absorption, which can improve
oral and
transmucosal bioavailability as well as increase transport across the blood-
brain barrier.
[00127] Synthetic methods to make compounds having the above-described
structure
may be derived by the skilled artisan from methods known in the art, such as
those
described in U.S. Patents 5,366,979; 6,713,488; 6,784,187; 4,912,114;
4,272,540;
4,322,426; 4,722,928; 4,990,617; 4,673,679; 4,668,685; 6,569,449; 4,535,157
and
5,908,846, as well as in U.S. Provisional Patent Application 60/813,845, filed
June 15,
2006 and entitled "ORALLY AVAILABLE NALOXONE DERIVATIVES AND
METHODS OF SYNTHESIS," each of which is hereby incorporated herein by
reference.
[00128] In certain embodiments of the invention, R is allyl. Compounds in
which R
is allyl tend to have desirably short compound half lives.
[00129] In certain embodiments of the invention, R' is not H. For example, R'
may
be o-aminobenzoyl or o-(acetyloxy)benzoyl. R' may also be (CI-Clgalkyl) or(CI-
CIs
alkyl)CO-. One especially desirable identity for R' is (C~-C5 alkyl)CO-. As
used herein, a
(Ca-CR, alkyl) group is a straight-chain or branched alkyl chain having n-m
carbon atoms.
[00130] In certain embodiments of the invention, R2a and R2b taken together do
not
make 0=. Such compounds are more lipophilic and have greater opiate receptor
activity
than do the naloxone compound. For example, R~a and R~b may each be H, or may
be
taken together to form CH2=.
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00131] In certain especially desirable embodiments of the invention, R' is
not H
and R2a and R2b taken together do not make 0=. Such compounds have especially
increased oral bioavailability and blood-brain barrier transport.
[00132] In certain embodiments of the invention, R3 is not OH.
[00133] One example of a suitable delta receptor selective antagonist has the
structure:
HO ~
OH
HN
[00134] The initial dosage of the mu/and or delta opiate receptor is desirably
high
enough to induce a counteradaptive effect, but not so high as to cause the
patient
intolerable direct effects. For example, the initial dosage of the mu and/or
delta opiate
receptor antagonist may be equivalent to between about 2 mg/administration and
about 200
mg/administration of naloxone. In certain desirable embodiments of the
invention, the
initial dosage of the mu and/or delta opiate receptor antagonist is equivalent
to between
about 10 mg/administration and about 100 mg/administration of naloxone.
[00135] When using naloxone as the mu and/or delta opiate receptor antagonist,
the
initial dosage may be between 5 and 500 mg/administration. Desirably, the
initial dosage
is between 10 and 50 mg/administration. In certain embodiments of the
invention, each
dosage of naloxone is greater than 10 mg/administration; greater than 10.5
mg/administration; greater than 11 mg/administration; or greater than 15
mg/administration. Desirably, the initial dose of naloxone is at least about
30
mg/administration (over 8 hour period), as this amount results in a complete
blockade of
opiate receptors. Desirably, the maximum dosage of naloxone is no greater than
3000
mg/administration.
36
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[001361 In one example of a daily dosing regimen for naloxone, the initial
dosage of
naloxone is 30 mg/administration over an 8 hour period. After two weeks, the
dosage is
doubled. After another two weeks, the dosage is increased to 120-160
mg/administration.
After another month, the dosage is increased to 300 mg/administration, then to
500-600
mg/administration after another two months. After another two months, the
dosage is
increased to 1000 mg/administration, then to 1500-2000 mg/administration after
another
two months. Alternatively, a much larger initial dose (e.g., 100-500
mg/administration)
could be used in order to build up a counteradaptation more quickly. A low
dose of
naltrexone (e.g., 10-25 mg/administration) could be used along with the
naloxone to realize
an additional counteradaptive effect.
[00137] In one example of a dosing regimen for naltrexone, an initial dosage
of 10-
25 mg naltrexone is given daily. Alternatively, larger doses (e.g., 25-200
mg/administration) are given once, twice, or thrice weekly. With larger doses
of
naltrexone, the first time period will be relatively long, and may
occasionally overlap with
the waking hours of the patient.
[0013$J The mu and/or delta opiate receptor antagonist may be administered
orally,
transdermally, intraspinally, intrathecally, via inhalation, subcutaneously,
intravenously,
intramuscularly, or transmucosally, or via osmotic pump, microcapsule,
implant, or
suspension. In certain embodiments of the invention (e.g., where the mu and/or
delta
opiate receptor antagonist has a relatively short compound half-life), it may
be desirable to
administer it using a time-release or slow-release formation, or transdermally
(e.g., using a
patch) in order to provide an administration half-life of sufficient length.
When the mu
and/or delta opiate receptor antagonist is administered transdermally or using
a time-
release or slow-release formulation, it is desirably released over a time
period between two
and twelve hours in duration; between two and six hours in duration; or
between six and
twelve hours in duration. In order to provide a high in vivo concentration of
the ligand in a
short amount of time, it may be desirable to administer the mu and/or delta
opiate receptor
antagonist using a rapidly absorbed loading dose. To provide a high in vivo
concentration
of the ligand quickly as well as a desirably long administration half-life, it
may be desirable
to use both a rapidly absorbed loading dose and transdennal administration or
a time-
release or slow-release formulation. A transderrnal patch for naloxone, -
naltrexone and
nalbuphine is disclosed in U.S. Patent 4,573,995, which is hereby incorporated
herein by
reference in its entirety. The invention herein further includes the
simultaneous use of oral
37
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
and transmucosal opiate antagonist routes of administration. The reason for
this is that the
transmucosal application is intended to result in rather immediate high
circulation levels of
the opiate antagonist compound. When using one of the aforementioned prodrugs,
such
administration would also result in immediate high levels of intracranial
opiate antagonist.
Such rapid high levels of the opiate antagonist are important when the intent
is to induce an
optimal counteradaptive response.
[00139] Another aspect of the invention relates to the option that an oral
dose of the
opiate antagonist may be given along with the transmucosal dose. Whereas the
transmucosal administration results in rapid circulating levels that last a
short period of
time, the oral compound has a gradual onset of circulating levels, and thus
this forr-a of
administration is intended to maintain relatively high circulating levels of
the opiate
antagonist compound in circulation for a more prolonged period of time, ie.,
up to 8 hours.
For example, if the native naloxone molecule or a 3-OH acetyl modification
were
administered by a transmucosal route, then the effects would only last in the
circulation for
2-4 hours, which is in essence the result of a half-life of 1- 1.5 hours for
these compounds.
Because the counteradaptive response will be maximized if the opiate
antagonist effect is
more prolonged, ie., up to 8 hours - the time spent sleeping, then the oral
naloxone analog
would result in a more prolonged period of time with elevated circulation
levels of the
naloxone. In other words, the dose that is given by the transmucosal route is
intended to
generate rapid circulation levels that last for a short period of time, while
the oral dose
would maintain the circulating levels for up to 8 hours.
[00140] Another aspect of the invention relates to the use of variable
administration
routes. For example, one may choose to begin therapy with one of the
aforementioned 3-
hydroxymorphinan compounds by a transmucosal route of administration. This
would be
done with lower doses of the compound in order to decrease acute side effects.
After a
period of time one may switch to oral administration, where larger doses would
be more
practical, and by which time the individual would have adapted to side
effects.
[00141] In certain embodiments of the invention, it may be desirable to
administer
both a specific mu and/or delta receptor antagonist and a non-specific mu
and/or delta
opiate receptor antagonist. The two types of antagonist may be administered
substantially
simultaneously or sequentially. Because the non-specific antagonists generally
provide a
38
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
greater counteradaptive effect than do specific mu or delta opiate
antagonists, it is desirable
to administer non-specific antagonists in the early stages of the method.
[00142] Because the body develops a tolerance to anti-opiates about eight days
after
first administration, it may be desirable to increase the dosage of the mu
and/or delta opiate
receptor antagonist with time. For example, it may be desirable to increase
the dosage with
a period of between a week and two weeks.
[00143] Desirably, an endorphin receptor agonist is not administered during
the first
time period associated with each administration. In certain embodiments of the
invention,
however, an endorphin receptor agonist is administered during one or more of
the second
time periods. Suitable but non-limiting examples of endorphin agonists include
opiates
such morphine, codeine, hydrocodone, fentanyl, and oxycodone. Morphine may be
administered at dosages of I- 20 - 50 mg i.v. or 1- 50 mg/hour continuous
release via
any suitable means such as transdermal, i.v., SQ, IM, or pump; Fentanyl may be
administered at dosages of 0.1 - 0.5 mg gradual release over 8 hours via any
suitable
means such as transdermal, SQ, IM, or pump; Codeine may be administered at
dosages of
- 100 mg p.o. every 4- 6 hours; Hydrocodone may be administered at dosages of
5 -
25 mg p.o. every 4-6 hours; Oxycodone may be administered at dosages of 5- 100
mg p.o.
every 4 hours by any suitable means such as slow release transdermal, i.m., or
SQ over 4-8
hours).
[00144] = Enkephalins having an amino acid sequence of H-Tyr-Gly-Gly-Phe-Met-
OH or H-Tyr-Gly-Gly-PheLeu-OH or any active analogues of these amino acid
sequences
with pharmacologically accepted carriers. Enkephalins may be administered at
dosages of
1.0 g/hr continuous release (transdermat, i.v., SQ, i.p. i.m. infusion pump).
[00145] Beta endorphin (a 31 amino acid peptide) or any and all active
analogues,
eg., beta-endorphin-(1-26), [D-Ala2]beta-endorphin or [LeuS]beta-endorphin
with accepted
pharmacologically accepted carriers. Beta endorphins may be administered at
dosages of
1.0 gfhr continuous release (e.g. transdermal, i.v., SQ, i.p. i.m. infusion
pump).
[00146] Mu selective agonists such as Carfentanil which may be administered at
a
dosage of 1-25 g(lcg; [D-Ala2, NMe-Phe4, Gly-o15] enkephalin and any active
analogue
with pharmacologically accepted carriers. The enkephalins may be administered
at a
suggested dosage of 1.0 g/hr continuous release (e.g. i.v., i.m., SQ, pump,
or transdermal).
39
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00147] Delta selective agonists such as DPDPE ([D-Pen2,D-Pen5]enkephalin); SB-
235863; and SNC 80. DPDPE may be administered at a suggested dosage of 1.0 --
5.0
g/hr continuous release (e.g., i.v., i.m., SQ, pump, or transdermal). SB-
235863, ([8R-
(4bS*,8aa,8a(3,12b[3)]7,10-Dimethyl-l-methoxy-ll-(2-methylpropyl)oxycarbonyl
5,6,7,8,12,12b-hexahydro-(9H)-4,8-methanobenzofuro[3,2-e]pyrrolo[2,3-
g]isoquinoline
Hydrochloride) may be administered at a dosage of 70mg/kg p.o. See Paola
Petrillo, et al.
J. Pharmacology and Experimental Therapeutics, First published on October 9,
2003 ;
DOI: 10.1124/jpet.103.055590. SNC 80 may be administered at a dosage of 50 -
75 mg/kg
slow release over several hours, transdermal, i.p. SQ, pump, etc.) See EJ
Bilsky, et al.,
Pharnacology and Experimental Therapeutics, Volume 273, Issue 1, pp. 359=366,
04/01 / 1995.
[00148] It may be desirable to administer a CRF receptor antagonist during the
second time period. Suitable CRF receptor antagonists include R121919, DMP696,
antalarmin, CP-154,526, SSR125543A, 2-arylamino-4-trifluoromethyl-
aminomethylthiazole antagonists, astressin, alpha-helical CRF compounds, as
well as the
compounds described in U.S. Patents 5,132,111; 5,278,146; 5,824,771;
5,844,074;
6,214,797; 6,670,371; 6,812,210 and 6,953,838 (each of which is hereby
incorporated
herein by reference) and phannaceutically acceptable salts, analogues, and
derivatives
thereof. The CRF system is described in more detail below.
[00149] It may be desirable to administer a CRF agonist in combination with
the mu
and/or delta opiate receptor antagonist, each administration of the CRF
receptor agonist
having an administration half-life, wherein the ratio of the administration
half-life to the
period between administrations is no greater than 1/2. Suitable CRF receptor
agonists
include analogues of corticotropin releasing factor, and pharmaceutically-
accepted salts
and derivatives thereof.
[00150] When using a CRF receptor agonist and/or an AVP receptor agonist in a
conventional dosing regimen, it may be desirable to repeatedly administer a mu
and/or
delta opiate receptor antagonist as described herein. This may be desirable
due to the fact
that the use of a CRF receptor agonist and/or an AVP receptor agonist may have
the
unintended consequence of down regulating the release of beta endorphin from
the anterior
pituitary gland. Such a reduced endorphin release would induce the opposite
effect as to
what is needed for the improvement of undesirable conditions that correlate
inversely with
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
the levels of circulating endorphins, such as depression and anxiety
disorders. The
repeated administration of the opiate antagonist may have two important
effects: to block
the endorphin down regulation by the CRF receptor agonist and or the AVP
receptor
agonist, and also to cause an up-regulation of the endorphin system as
described above.
Accordingly, in some embodiments of the invention a CRF receptor agonist
and/or an AVP
receptor agonist is administered during the second time period associated with
each
administration of the mu and/or delta opiate receptor antagonist.
[00151] The endogenous endorphin system and its mu and/or delta opiate
receptors
are negatively linked to a wide variety of undesirable mental and neurological
conditions.
Examples of such conditions include pain, mood disorders, eating disorders,
anxiety
disorders, motivational problems, substance abuse disorders, insufficient
motivation or
performance, immune system-related conditions, wounds in need of healing, pain
that is
expected to occur in the future (e.g., due to a future operation or due to
future physical
exertion), chronic pain syndromes, acute pain, fibromyalgia, chronic fatigue
syndrome,
chronic back pain, chronic headaches, shingles, reflex sympathetic dystrophy,
neuropathy,
inflammatory pain, chronic cancer pain, major depressive disorders, post
traumatic
depression, temporary depressed mood, manic-depressive disorders, dysthymic
disorders,
generalized mood disorders, anhedonia, non-organic sexual dysfunction,
overeating,
obesity, anorexia, bulimia, a generalized anxiety state, panic disorders,
Tourette's
Syndrome, hysteria sleep disorders, breathing-related sleep disorders, lack of
motivation
due to learning or memory problems, abuse of a substance such as narcotics,
alcohol,
nicotine, stimulants, anxiolytics, CNS depressants, hallucinogens and
marijuana,
insufficient motivation or preparation for a desired mental or physical
activity (e.g.
physical training, athletics, studying or testing), immune-related condition
such as
infection, AIDS, or cancer, and wounds in need of healing. The up-regulation
of the
endogenous endorphin system desirably causes a therapeutic benefit with
respect to the
undesirable mental, neurological or physiological condition.
[00152] The endogenous endorphin system is implicated in pain because
endorphins
can bind to pain-mediating opiate receptors and decrease the synthesis of SP,
a pain-
inducing substance. The endogenous endorphin system has also been implicated
in stress
(U.S. Patents 5,922,361 and 5,175,144), wound healing (Vinogradov VA, Spevak
SE, et al,
Bi and U.S. Patent 5,395,398), substance abuse, eating disorders (Full &
fulfilled : the
science of eating to your soul's satisfaction, by Nan Allison; Carol Beck,
Publisher:
41
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
Nashville, TN : A & B Books, 1998, ISBN: 0965911799), motivational problems
(Tejedor-Real, P, et al, Eur J Pharmacol. 1998 Jul 31;354(1):1-7); immune
response
(Wybran, Fed Proc. 1985 Jan;44(1 Pt 1):92-4, and U.S. Patent 5,817,628) and
cancer
(Zagon, IS, et al., Cancer Lett, 1997; 112:167-175; U.S. Patents 6,737,397;
6,136,780; and
4,801,614).
[00153] The endogenous endorphin system is also implicated in mood. Euphoria
is
the most recognizable emotional effect of opioids, which gives one an elevated
feeling of
well-being and care-free. Euphoria is modulated by endogenous endorphins.
Endorphins
are released with pleasurable experiences such as eating, exercise, winning an
event,
romantic encounters. It is thought that the endorphin release generates a
feeling of well-
being as a`reward', which acts as a motivational mechanism in order to inspire
an
individual to fulfill nutritional and reproductive requirements. Another
function of the
endogenous endorphin system with respect to mood is to decrease anxiety,
especially with
regards to stress response. Rang H. P. (1995). Peptides as Mediators. In H. P.
Rang & M.
M. Dale, Phar-nacology, Churchill Livingstone, New York.) demonstrates that
endorphins
are released at times of emotional stress, which acts to induce euphoria in
order that anxiety
is reduced.
[00154] Both endogenous endorphins and synthetic opiates may induce euphoria.
The difference is that endogenous endorphins are rapidly degraded at their
synapse and
receptor sites, such that the effect is short term. With a short term effect
there is no
development of tolerance or dependency. Synthetic opiates, such as narcotics,
have a much
longer reactive time, thus they are associated with the development of
dependency.
Synthetic opiates have not been developed that have both, a strong analgesic
effect and
little or no potential for the development of dependency. Because endogenous
endorphins
have a similar euphoria-inducing capability as do opiates it is advantageous
to use
endogenous endorphins for inducing an elevated mood. However, because the
administration of relatively large and prolonged doses of synthetic endorphins
may be
associated with the development of tolerance and dependency, they are not
desirable long-
term treatment agents.
[00155] Both mu and delta opiate receptors are involved to some degree with
mood.
Mu receptors primarily mediate pain perception, but also induce euphoria when
these
receptors are bound by endorphin/ opiate compounds. The role of delta
receptors in pain
42
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
modulation is not clear, whereas they are likely more closely related to
euphoria. Delta
receptor agonists demonstrate anti-depressant activity in rats in the forced
swim assay.
Furthennore, evidence from animal studies demonstrates that delta-opioid
receptors are
involved in motivational activities. Their preferential involvement is through
enkephalin-
controlled behavior. Broom, et al. (Jpn J. Pharmacol_ 2002 Sep;90(1):1-6)
demonstrate
that the delta opiate receptor plays a significant role in depression.
[00156] Methods of the present invention using mu and/or delta receptor
antagonists
as ligands may be used to address undesirable mental, neurological or
physiological
conditions in patients. For example the methods of the present embodiment of
the
invention may be used to address any of the above-listed conditions. The
methods
according to the present embodiment of the invention may also be used as an
adjunct
treatment for cancer.
[00157] Methods of the present invention using mu and/or delta receptor
antagonists
may be used to address pain that is anticipated to occur in the future. For
example, if a
patient is scheduled for elective surgery in, e.g., one month then the method
of the present
invention can be practiced with a mu and/or delta opiate receptor, using high
night-time
dosing for the intervening pre-operative period of time. After surgery the
patient will have
an enhanced response to pain due to the up-regulated endogenous endorphin
system. In
addition, the patient will require lower overall doses of narcotic pain
medications post-
operatively due to enhanced sensitivity of mu and/or delta opiate receptors.
The method
would likely best interrupted immediately after surgery so that post-operative
pain would
not increase due to the direct effects of receptor antagonism. It could be
restarted in a few
days or so, once the pain had subsided, in order to maintain the
counteradaptive response.
[00158] In an example of a pre-operative treatment according to the present
invention, a 49 year old male is scheduled for reconstructive surgery on his
knee in 6
weeks. He is begun on a naloxone patch, 200 mg, which is formulated to be
rapidly
absorbed over 6-8 hours as described above, on a nightly basis. To reduce the
anxiety that
this induces he is given an anxiolytic agent, diazepam (1-5 mg) at night along
with the
naloxone patch. After 2 weeks of this dose, the naloxone is increased to 400
mg on a
nightly basis. The anxiolytic agent is used if needed. After yet an additional
2 weeks the
naloxone is increased to 600-800 mg on a nightly basis. On the night of
surgery and for
several nights in the peri-operative period no naloxone is given. The patient
is given only
43
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
standard post-operative pain medications such as morphine and codeine. The
doses of
these substances are significantly reduced compared to the average individual
undergoing
this type of surgery, due to the up regulation of this patient's endorphin
system. In an
alternative method, after the first 2 weeks of naloxone treatment, the same
patient is given
a specific mu receptor antagonist along with the increasing dose of naloxone,
in order to
enhance the up regulation of pain-modulating mu receptors.
[001591 The methods of the invention may be used with mu and/or delta
antagonists
to elevate a patient's mood in the treatment of depression and related
conditions_ At first,
non-specific opiate receptor antagonists (e.g., naloxone) may be administered
to induce a
counteradaptive response. Later in the treatement, it may be desirable to
administer. a
specific delta opiate receptor antagonist because delta opiate receptors are
strongly linked
to mood. Of course, mu opiate receptor antagonists could be used, especially
when chronic
pain is associated with the depressed mood. When treating an already-depressed
patient,
the skilled artisan will closely monitor the patient for ill effects due to
any acute worsening
of mood due to antagonist-receptor binding.
[00160] " In an example of a method of treating a depressed patient using the
methods
of the present invention, a 35 year old male with a diagnosis of clinical
depression has had
poor response and side effects with conventional antidepressant agents. He is
especially
consulted on the potential for temporary worsening of the depressed state,
including
suicidal tendencies. In-patient treatment in a hospital or appropriate mental
institution is
considered at the onset of therapy for higher risk potentially suicidal
patients. After this is
worked out, he is started on counteradaptation therapy protocol with the non-
specific opiate
antagonist naloxone. A transmucosal naloxone formulation is started prior to
going to
sleep, using a loading dose of 20 mg. A 30 mg transdermal dose, formulated to
be
absorbed over 6 hours, is applied at the same time. This 50 mg per 8 hour dose
is given for
two weeks. At two weeks the transmucosal dose is increased to 50 mg. The 6
hour
transdermal dose is 50 mg, for a total of 100 mg. This dose is given for one
month. Now,
at 6 weeks after treatment had begun, the loading dose is 100 mg transmucosal
and 100 mg
transdermal over 6 hours. After another 4-6 weeks this is increased to 250 mg
loading dose
and 250 mg over 6 hours for a total 500 mg. After another on to two months
this is
increased to 500 mg loading dose and 500 mg over the next 6 hours. After
another one or
two or three months this is increased to a 1000mg loading dose and a 1000 rrig
6 hour
transdermal dose. The maximal can stay for a long period of time at this 2000
mg total
44
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
dose. Or it can continue to increase to 2,500, or 3,000 or 4,000mg over the
ensuing year or
more. The maximal dose comes to a plateau once there is a good clinical
response or once
the side effects become too great or if there is an elevation of liver
function enzymes on a
blood test. The maximum tolerable dose is then given for an extended period of
time for
maintenance therapy. If and when therapy is stopped the patient is carefully
monitored for
any signs of recurrence of the mood disorder.
[00161] An option for the above-described patient is to add a delta opiate
receptor
antagonist, along with the naloxone after the first 6 weeks to 3 months of
treatment. The
naloxone dose may continue to be increased or it may level off earlier when
combined with
the delta antagonist. A non-peptide delta opiate receptor antagonist, such as
naltrindole,
natriben, or one of the agents discussed above, could be used. A peptide delta
antagonist,
such as ICI-154,129 or ICI-174,864 peptide, could also be used. The starting
dose for
naltrindole is larger than that for naloxone. It may be as high as 10
mglkg/administration.
Naltrindole may be given as a transdermal compound or using any other
effective
formulation.
[00162] The main consideration is the dosing for people with significant
depression
who may be at risk for suicide if the initial doses are too large. In a
desirable embodiment
of the invention, people with clinical depression, because they are suicidal
risks, should
either not be treated or treated at an in-patient hospital or appropriate
institution in order to
better monitor the patient. These patients are dosed at relatively lower doses
at the
beginning of treatment and that the increase in dose is done at a slower rate.
Thus, for the
depressed patients treatment may need to be started with a loading of only 10
mg of
naloxone, with 10 or 20 mg to be absorbed over the ensuing 6 hours, for a
total starting
dose of 30 mg. Similarly, the increase in dose after 2 weeks is more gradual
than for the
example above. At 2 weeks one would give 20 mg as a loading dose and 20-40 mg
over
the ensuing 6 hours. This gradual increase is continued for as many months as
is needed to
obtain a maximal clinical response.
THE DYNORPHIN SYSTEM
[00163] According to another embodiment of the invention, the neurotransmitter
system is the dynorphin system, which includes dynorphins as
neurotransmitters.
Dynorphins are a class of endorphin compounds that bind preferentially to
kappa receptors.
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
Dynorphins generally have the opposite effect from the endorphins; their
binding to kappa
receptors is generally associated with a worsening of mood.
[00164] When the neurotransmitter system is the dynorphin system, the type of
receptor is kappa receptors, which are generally positively linked to
undesirable mental,
neurological and physiological conditions. Kappa receptors are associated
primarily with
dysphoria when stimulated. The ligand is a kappa receptor agonist, and the
counteradaptation causes a down-regulation of the dynorphin system. The
counteradaptation may be, for example, a decrease in the biosynthesis or
release of
dynorphins at receptor terminals and/or by the pituitary gland; a decrease in
the number of
the receptors and/or dynorphin binding sites on the receptors; a decrease in
the sensitivity
of the receptors to binding by mu and/or delta receptor agonists and/or
dynorphins; or any
combination thereof. The counteradaptation may also up-regulate D2 (dopamine)
receptors, which are negatively linked to depression.
[00165] A variety of kappa receptor agonists may be used in the present
invention.
For example, the kappa receptor agonist may be a peptide-based agonist, such
as dynorphin
[Dynorphin [A1-17], H-TYR-GLY-GLY-PHE-LEU-ARG-ARG-ILE8-ARG-PRO-LYS-
LEU-LYS-TRP-ASP-ASN-GLN-OH] and all active peptide fragments and analogues
thereof or a pharmaceutically acceptable salt, or carrier thereof. For
example, the kappa
receptor agonist may be the active C-terminal fragment of dynorphin A(I-8), or
a
pharmaceutically accepted salt or carrier thereof.
[00166] The kappa receptor agonist may also be non-peptidic. For example, the
kappa receptor agonist may be a nonbenzomorphan; enadoline; PD117302; CAM569;
PD123497; GR 89,696; U69,593; TRK-820; trans-3,4-dichloro N-methyl N-[1-(1-
pyrrolidinyl)cyclohexyl]benzene-acetamide; asimadoline (EMD-61753);
benzeneacetamide; thiomorpholine; piperidine; benzo[b]thiophene-4-acetamide;
tra.ns-(+/-
)-(PD-117302); 4-benzofuranacetamide (PD-129190); 2,6-methano-3-benzazocin-8-
ol
(1VIR-1268); morphinan-3-ol (KT-90); GR-45809; 1-piperazinecarbox.ylic acid
(GR-
89696); GR-103545; piperzaine; GR-94839; xorphani; benzeneacetamide (RU-
49679);
fedotozine; benzeneacetamide (DuP-747); HN-11608; apadoline (RP-60180);
spiradoline
mesylate; benzeneacetamide trans-U-50488 methane sulfate; 3FLB; FE200665;
FE200666;
an analogue of MPCB-GRRI or MPCB-RRI; benzomorphan kappa opioids, such as
46
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
bremazocine and ethylketocyclazocine; or a pharmaceutically-accepted salt or
carrier
thereof.
[00167] The kappa receptor agonist may be U50,488 (trans-3,4-dichloro-N-[2-(1-
pyrrolidinyl)cyclohexyl]benzeacetamide); spiradoline (U62,066E); Enadoline
[(5R)-5a, 7a,
8 R)-N-methyl-N-[7-(1-pyrrolidinyl)-1-oxzspiro [4,5]dec-8-yl]-4-
benzofuranacetamide
monohydrochloride] orPD117302 [(f)-trans N-methyI-N-[2-(1-pyrrolidinyl)-
cyclohexyl]benzo[b]thiophene-4-acetamide monohydrochloride] and their
respective (+)-
isomers (CAM569 and PD 123497) (Parke-Davis Research Unit, Cambridge, UK),
each of
which are highly selective arylacetamide kappa opioids; GR89,696 (4-[(3,4-
dichlorophenyl)acetyl]-3-(1-pyrrolidinylmethyl)-1-piperazinecarboxylic acid
methyl ester
fumarate), a prototypical arylacetamide developed from the structure of
U50,488H having
high efficacy as a Ki agonist; U69,593 [(5a,7a,8R)-(+) N-methyl-N-(7-(1-
pyrrolidinyl)-1-
oxaspiro[4,5]dec-8-yl)benzeneacetamide], a kappa agonist with K, selectivity;
TRK-820 ((-
)-17-cyclopropylmethyl-3,14b-dihydroxy-4,5a-epoxy-6b-[N-methyl-trans-3-(3-
furyl)
acrylamide]morphinan hydrochloride) (Toray Industries, Inc. Japan), a potent
kappa
agonist with pharmacological properties different from those produced by Kt
receptor
agonists; tifluadom, a benzodiazepine kappa agonist (Sandoz, Inc., Princeton,
N.J.); or
trans-3,4-dichloro-N-methyl-N-[1-(1-pyrrolidinyl)cyclohexyl]benzeneacetamide,
a kappa
agonist described in U.S. patent 4,758,562.
[00168] Kappa receptor agonists are also described in U.S. Patents 5,051,428;
5,965,701; 6,146,835; 6,191,126; 6,624,313; 6,174,891; 6,316,461; 6,440,987;
4,758,562;
6,583,151, each of which is incorporated herein by reference in its entirety.
[00169] The initial dosage of the kappa receptor agonist is desirably high
enough to
induce a counteradaptive effect, but not so high as to cause the patient
intolerable direct
effects. For example, the initial dosage of the kappa receptor agonist may be
equivalent to
between 0.0005 and 0.05 mg/kg/administration of dynorphin; between 5 and 700
mg/administration of enadoline; between 1 and 500 g/administration of FE
20665;
between 0.5 and 100 g/administration; between 0.01 and 1 mg/kg/administration
of
U69,593; between 0.05 and 5 mg/kg/administration of TRK 820; between 0.01 and
1
mg/kgladministration U 50 488 or between 0.01 and 1 mg/kg/administration of PD
117302.
Desirably, the initial dosage of the kappa receptor agonist is equivalent to
between 0.005
and 0.02 mg/kg/administration of dynorphin; between 100 and 500
mg/administration of
47
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
enadoline; between 3 and 100 g/administration of FE 20665; between I and 80
g/administration of FE 20666; between 0.1 and 0.7 mg/kg/administration of
U69,593;
between 0.5 and 3 mg/kg/administration of TI2K 820; between 0.5 and 7
mg/kg/administration U 50 488 or between 0.1 and 0.7 mg/kg/administration of
PD
117302.
[00170] In another embodiment of the invention, the kappa receptor agonist is
Salvinorin A. Salvinorin A is a neoclerodane diterpene compound, which is a
very
powerful hallucinogen that has recently been found to have kappa agonist
activity. It
represents the only known non-nitrogenous kappa agonist compound. It is the
main active
ingredient of the plant S. divinorum (Diviner's sage), a rare member of the
mint family. It
has been used for many centuries by the Mazatec people of Oaxaca, Mexico in
traditional
spiritual practices. The initial dose of Salvinorin A is desirably between 5
and 50
g/administration, and the maximum dose is desirably 5000 g/administration.
The
Salvornin A may be administered transmucosally, or as a slow-release
formulation,
desirably over a period between two and six hours in duration.
[00171] In certain embodiments of the invention, it may be desirable to
administer
both a peptidic kappa receptor agonist and a non-peptidic kappa receptor
agonist. The two
types of agonist may be administered substantially simultaneously, or
sequentially.
[00172] Peptidic kappa receptor agonists may be administered, for example,
intravenously, transdermally, or transmucosally, as described above with
respect to otber
peptidic ligands. As described above with respect to naloxone, it may be
desirable to use
transmucosal administration (to achieve a high level of ligand-receptor
binding quickly)
along with transdermal administration (to provide extended ligand-receptor
binding).
[00173] Because the body develops a tolerance to anti-opiates about eight days
after
first administration, it may be desirable to increase the dosage of the kappa
receptor agonist
with time. For example, it may be desirable to increase the dosage with a
period of
between a week and two weeks.
[00174] In an example of a method of the present invention using Salvinorin A,
the
initial dose of Salvinorin A is low in order to decrease potential side
effects. A dose
between 5 gg-50 }ig is the starting dose. After 2- 4 weeks this is increased
by a certain
percent. The increase could be as small as 5-10% or 50-100% or more.
Generally, a
48
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
doubling of the initial dose is recommended. Thus, after 2-4 weeks the
individual is given
20-100 .g of Salvinorin A. This increase in dose is continued every two,
four, six or eight
weeks. It may also continue to increase on a quarterly, semiannual or annual
basis. Doses
of 200 g may produce increasing dysphoric effects. This occurs with acute
administration. With chronic gradual increase in dose the side effects would
be gradually
muted. With chronic gradual increase in dosing the maximum dose of Salvinorin
A is 1000
g to 5000 g or more.
[00175] In an example of the method of the present invention using a dynorphin
analogue, a rectal suppository (transmucosal) formulation is used. The initial
dose is high
enough in order to induce a counteradaptive response, but low enough to
minimize
dysphoric effects of agonist-receptor binding. There is a two-part construct
of the
suppository. The outer covering is rapidly dissolved and allows for an initial
rapid
absorption of the kappa receptor agonist compound. The second layer is
gradually broken
down in order to slowly release additional kappa receptor agonist, which is
gradually
absorbed. This results in a continuous, slow-release absorption of the peptide
kappa
receptor agonist compound. It is designed to last for 6-8 hours of gradual
absorption such
that there is 6-8 hours of kappa receptor binding, at which time the
counteradaptive
response is induced. This rectal suppository is given on a daily (nightly)
basis. After 2-4
weeks the dose is doubled. This dose is then given for an additional 2-4-6-8
weeks. The
dose is intermittently increased until the development of side effects
prevents a further
increase. As the dose is increased the time interval for increasing the dose
is lengthened,
such that several months may pass before increasing the dose. In addition,
once higher
doses are used the increase is less dramatic, such that only 5-10% increases
are given,
rather than the initial doubling of the dose.
[00176] Enadoline is a non-peptidic kappa receptor agonist. It has
pharmaceutical
activity when taken as an oral dose at 1-10 mg/kg. In an example of a method
of the
present invention using enadoline, an initial dose of 100-200 mg is
administered daily just
prior to the patient's going to bed. After 2-4 weeks the dose is increase to
200-500 mg.
After another 2-4 weeks the dose is increased to 500-1000 mg. After another
two, four,
eight weeks or more, it is increased to 1500-2000 rng. The dose is increased
as long as side
effects do not become uncontrollable.
49
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00177] Desirably, a kappa receptor antagonist is not administered during the
first
time period associated with each administration. In certain embodiments of the
invention,
however, a kappa receptor antagonist is administered during one or more of the
second
time periods. Representative kappa receptor antagonists include the compounds
described
in U.S. Patent no. 5,025,018; 5,922,887; and 6,284,769. For the compounds
described in
5,025,018, a suitable dosage includes 0.1 to 10 mg/administration per day; for
U.S. Patent
no. 6,284,769, suitable dosages include 0.1 to 500 mg/administration.
[00178] The dynorphin neurotransmitter system and its kappa receptors are
positively linked to a wide variety of undesirable mental and neurological
conditions.
Examples of such conditions include pain, mood disorders, eating disorders,
anxiety
disorders, motivational problem, substance abuse disorders, insufficient
motivation or
performance, pain that is expected to occur in the future (e.g., due to a
future operation or
future physical exertion), chronic pain syndromes, acute pain, fibromyalgia,
chronic fatigue
syndrome, chronic back pain, chronic headaches, shingles, reflex sympathetic
dystrophy,
neuropathy, inflammatory pain, chronic cancer pain, major depressive
disorders, post
traumatic depression, temporary depressed mood, manic-depressive disorders,
dysthymic
disorders, generalized mood disorders, anhedonia, non-organic sexual
dysfunction,
overeating, obesity, anorexia, bulimia, generalized anxiety state, panic
disorders, Tourette's
Syndrome, hysteria sleep disorders, breathing-related sleep disorders, lack of
motivation
due to learning or memory problems, abuse of substances such as narcotics,
alcohol,
nicotine, stimulants, anxiolytics, CNS depressants, hallucinogens and
marijuana, and
insufficient motivation or preparation for a desired mental or physical
activity such as
physical training, athletics, studying or testing. The down-regulation of the
dynorphin
system desirably causes a therapeutic benefit with respect to the undesirable
mental,
neurological or physiological condition.
THE SEROTONIN SYSTEM
[00179] According to another embodiment of the invention, the neurotransmitter
system is the serotonin system which includes serotonin as a neurotransmitter.
Serotonin is
a monoamine neurotransmitter. Low serotonin levels are associated with
depression. The
counteradaptation causes an up-regulation of the serotonin system.
[00180] Numerous serotonin receptors (at least 14) have been identified. The
greatest concentration of serotonin (90%) are located in the gastrointestinal
tract. Most of
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
the remainder of the body's serotonin is found in platelets and the central
nervous system
(CNS). The effects of serotonin are noted in the cardiovascular system, the
respiratory
system and the intestines. Vasoconstriction is a typical response to
serotonin.
[00181] The function of serotonin is exerted upon its interaction with
specific
receptors. Several serotonin receptors have been cloned and are identified as
SHTI, 5HT2,
5HT3, 5HT4, 5HT5, 5HT6, and 5HT7. Within the SHTt group there are subtypes
5HTI A,
5HTig, 5HTiD, 5HTIE, and SHTIF. There are three 5HT2 subtypes, 5HT2A, 5HT2B,
and
5HT2C as well as two 5HTS subtypes, 5HT5a and 5HT5g. Most of these receptors
are
coupled to G-proteins that affect the activities of either adenylate cyclase
or phospholipase
Cg. The 5HT3 class of receptors are ion channels
[00182] Some serotonin receptors are presynaptic and others postsynaptic. The
5HT2A receptors mediate platelet aggregation and smooth muscle contraction.
The 5HT2C
receptors are suspected in control of food intake as mice lacking this gene
become obese
from increased food intake and are also subject to fatal seizures. The 5HT3
receptors are
present in the gastrointestinal tract and are related to vomiting. Also
present in the
gastrointestinal tract are 5HT4 receptors where they function in secretion and
peristalsis.
The 5HT6 and 5HT7 receptors are distributed throughout the limbic system of
the brain and
the 5HT6 receptors have high affinity for antidepressant drugs.
[00183] The most common serotonin receptors that are associated with mood and
depression are the 15` and 2"d ones, most especially the 5HTIA receptors.
[00184] When a serotonin neuron is stimulated to fire, serotonin is released
into the
synapse. Some serotonin molecules cross the synapse and bind to the post-
synaptic
receptor, which then causes firing of the post-synaptic serotonin neuron.
Binding of
serotonin to the post-synaptic serotonin neuron causes its activation, which
leads to a series
of neural events that is associated with a generally good mood.
[00185] When serotonin is released into the synaptic cleft only a portion of
the
serotonin actually binds to post-synaptic receptors. The majority of serotonin
molecules
are removed from the synapse by a reuptake mechanism. Some of this serotonin
is
degraded by monoamine oxidases, enzymes that degrade both serotonin and
norepinephrine.
51
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00186] The third target of serotonin molecules are the pre-synaptic auto-
receptors.
The pre-synaptic autoreceptors are inhibitory receptors. The pre-synaptic
autoreceptors act
in a feedback inhibition loop that functions as a control mechanism for
neurotransmitter
release. A feedback inhibition loop is a common manner by which the body
controls the
activation of neurons. When they are bound by sertonin, or an agonist, they
inhibit the
further release of sertonin into the synapse. Pre-synaptic autoreceptors are
termed 5HT1A
and 5HTIB pre-synaptic autoreceptors. 5HTIA autoreceptors inhibit the tonic
release of
serotonin. 5HTIB autoreceptors are thought to inhibit the evoked release and
synthesis of
serotonin.
[00187] When the neurotransmitter system is the serotonin system, the type of
receptor may be, for example, serotonin pre-synaptic autoreceptors such as
5HTIA
autoreceptors or 5HTIB autoreceptors. In such cases, the ligand is a serotonin
pre-synaptic
autoreceptor agonist, and the undesirable mental, neurological or
physiological condition is
positively linked to the receptors. The counteradaptation may be, for example,
an increase
in the biosynthesis and/or release of serotonin at the synaptic cleft; a
decrease in the
reuptake of serotonin; a decrease in the number of serotonin pre-synaptic
autoreceptors; a
decrease in the sensitivity of the serotonin pre-synaptic autoreceptors to
serotonin and/or
serotonin pre-synaptic autoreceptor agonists; an increase in the number of
serotonin post-
synaptic receptors; an increase in the sensitivity of the serotonin post-
synaptic receptors to
serotonin or serotonin post-synaptic receptor agonists; or any combination
thereof.
[00188] A variety of serotonin pre-synanptic autoreceptor agonists may be used
in
the methods of the present invention. For example, the serotonin pre-synaptic
autoreceptor
agonist may be EMD-68843, buspirone, gepirone, ipsapirone, tandospirone,
Lesopitron,
zalospirone, MDL-73005EF, or BP-554.
[00189] The initial dosage of the serotonin pre-synaptic autoreceptor agonist
is
desirably high enough to induce a counteradaptive effect, but not so high as
to cause the
patient intolerable direct effects. For example, the initial dosage of the
serotonin pre-
synaptic autoreceptor agonist may be equivalent to between 1 and 400
mg/administration
of EMD-68843, between 1 and 500 mg/administration buspirone, between 1 and 500
mg/administration lesopitron, between 1 and 500 mg/administration gepirone,
between 5
and 500 mg tandospirone, or between I and 200 mg zalospirone. Desirably, the
initial
dosage of the serotonin pre-synaptic autoreceptor agonist is equivalent to
between 10 and
52
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
100 mg/administration of EMD-68843, between 10 and 100 mg/administration
buspirone,
between 10 and 200 mg/administration lesopitron, between 10 and 100
mg/administration
gepirone, between 20 and 200 mg tandospirone, or between 10 and 100 mg
zalospirone.
[00190] Desirably, a serotonin pre-synaptic autoreceptor antagonist is not
administered during the first time period associated with each administration.
In certain
embodiments of the invention, however, a serotonin pre-synaptic autoreceptor
antagonist is
administered during one or more of the second time periods. Representative
serotonin pre-
synaptic autoreceptor 5HT1A agonists and antagonists include Elazonan, AR-A2
(AstraZeneca, London, UK); AZD-1 134 [AstraZeneca, London, UK); Pindolol, as
well as
compounds described in US 6,462,048; 6,451,803; 6,627,627; 6,602,874;
6,277,852; and
6,166,020, incorporated by reference in their entirety.
[00191) In another embodiment of the invention, the type of receptor is
serotonin
post-synaptic receptors, such as 5HT, receptors; 5HT2 receptors; 5HT3
receptors; 5HT4
receptors; 5HT5 receptors; 5HT6 receptors; 5HT7 receptors; or receptors of a
subtype
thereof. The ligand is a serotonin post-synaptic receptor antagonist.
Undesirable mental,
neurological or physiological conditions are generally negatively linked with
these
receptors. The counteradaptation may be an increase in the biosynthesis and/or
release of
serotonin at the synaptic cleft; a decrease in the reuptake of serotonin; an
increase in the
number of serotonin post-synaptic receptors; an increase in the sensitivity of
the serotonin
post-synaptic receptors to serotonin and/or serotonin post-synaptic receptor
agonists; a
decrease in the number of serotonin pre-synaptic autoreceptors; a decrease in
the sensitivity
of the serotonin pre-synaptic autoreceptors to serotonin and/or serotonin pre-
synaptic
autoreceptor agonists; or any combination thereof.
[00192] A variety of compounds may be used as the serotonin post-synaptic
receptor
antagonists in the methods of the present invention. For example, the
serotonin post-
synaptic receptor antagonists may be (S)-WAY-100135, WAY-100635, buspirone,
gepirone, ipsapirone, tandospirone, Lesopitron, zalospirone,lVIDL-73005EF, or
BP-554. If
desired, an SSRI maybe administered either simultaneously or sequentially with
the
aforementioned serotonin modulating agents. This is advantageous as both SSRI
and
agonist pre-synaptic counteradaptive therapy result in a down regulation of
the pre-synaptic
receptors. The SSRI effect is thus magnified by such a counteradaptive effect.
Second,
53
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
any down regulation of the post synaptic serotonin receptors that may occur
with SSRI
therapy is counterbalanced by post synaptic antagonist counteradaptive
therapy.
[00193] The initial dosage of the serotonin post-synaptic antagonist is
desirably high
enough to induce a counteradaptive effect, but not so high as to cause the
patient
intolerable direct effects. For example, the initial dosage of the serotonin
post-synaptic
ieceptor antagonist is equivalent to between about 0.01 and 5
mg/lcg/administration of
WAY-100635. Desirably, the initial dosage of the serotonin post-synaptic
receptor
antagonist is equivalent to between about 0.025 and 1 mg/kg/administration of
WAY-
100635.
[00194] The serotonin post-synaptic receptor antagonist may be administered in
combination with a serotonin pre-synaptic autoreceptor agonist, such as those
described
above. Further, when conventional anti-depressant agents that bind at the
serotonin post-
synaptic receptors are given in combination with a serotonin pre-synaptic
autoreceptor
agonist, its efficacy can be greatly increased because the serotonin post-
synaptic receptors
have increased in number and/sensitivity through the counteradaptation.
[00195] In certain desirable embodiments of the invention, the serotonin post-
synaptic antagonist itself is also a serotonin pre-synaptic autoreceptor
agonist. It may also
be desirable to administer a norepinephrine pre-synaptic alpha-2 adrenergic
receptor
agonist and/or a norepinephrine post-synaptic adrenergic receptor antagonist
(as described
below) in combination with the serotonin post-synaptic antagonist or serotonin
pre-synaptic
autoreceptor agonist.
[00196] Desirably, a serotonin post-synaptic receptor agonist is not
administered
during the first time period associated with each administration. In certain
embodiments of
the invention, however, a serotonin post-synaptic receptor agonist is
administered during
one or more of the second time periods. Representative serotonin post-synaptic
receptor
agonists include BIMT 17 (1-[2-[4-(3-trifluoromethyl phenyl) piperazin-1-yl]
ethyl]
benzimidazol- [1H]-2-one), dose: 1- 10 mg/kg (i.v. or transdermal, SQ, etc.).
See Borsini,
F, et a1.,.2rchives ofPharmacology, 352(3); Sept, 1995:283-290.] A suitable
dosage range
includes 1 to 10 mg/kg/administration of BIMT 17 (via iv, transdermal, or SQ).
[00197] Serotonin post-synaptic receptors are generally negatively linked, and
serotonin pre-synaptic autoreceptors are generally positively linked to a wide
variety of
54
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
undesirable mental and neurological conditions. Examples of such conditions
include pain,
mood disorders, eating disorders, anxiety disorders, obsessive-compulsive
disorders,
motivationai problem, substance abuse disorders, insufficient motivation or
performance,
pain that is expected to occur in the future (e.g., due to a future operation
or future physical
exertion), chronic pain syndromes, acute pain, fibromyalgia, chronic fatigue
syndrome,
chronic back pain, chronic headaches, shingles, reflex sympathetic dystrophy,
neuropathy,
inflammatory pain, chronic cancer pain, major depressive disorders, post
traumatic
depression, temporary depressed mood, manic-depressive disorders, dysthymic
disorders,
generalized mood disorders, anhedonia, non-organic sexual dysfunction,
overeating,
obesity, anorexia, bulimia, generalized anxiety state, panic disorders,
Tourette's Syndrome,
hysteria sleep disorders, breathing-related sleep disorders, lack of
motivation due to
learning or memory problems, abuse of substances such as narcotics, alcohol,
nicotine,
stimulants, anxiolytics, CNS depressants, hallucinogens and marijuana, and
insufficient
motivation or preparation for a desired mental or physical activity such as
physical training,
athletics, studying or testing. The up-regulation of the serotonin system
desirably causes a
therapeutic benefit with respect to the undesirable mental, neurological or
physiological
condition.
THE NOREPINEPHRINE SYSTEM
[00198] In another embodiment of the invention, the neurotransmitter system is
the
norepinephrine system which includes norepinephrine as a neurotransmitter, and
the
counteradaptation causes an up-regulation of the norepinephine system.
[00199] Norepinephrine is a catecholamine that, along with epinephrine, acts
as a
neurotransmitter in the central nervous system. There are two types of
adrenoreceptors, alpha
and beta. There are in addition, at least ten different subtypes of
adrenoreceptors.
Norepinephrine generally is more potent at sites where sympathetic
neurotransmission is
excitatory and is mediated through alpha receptors. Alpha receptors have two
main
subclasses, alpha 1 and alpha2.
[00200] Norepinephrine acts a neuromodulator in the central nervous system.
The
central nervous system actions of NE are most notable when it modulates
excitatory or
inhibitory inputs, rather than its effects on the activity of post-synaptic
targets, in the absence
of other inputs. Norepinephrine transmission and control is similar to that
for serotonin. A
reuptake mechanism is present that removes the majority of norepinephrine
after its release
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
into the noradrenergic synapse. There are pre-synaptic inhibitory
autoreceptors known as
alpha-2 adrenergic receptors.
[00201] When the neurotransmitter system is the norepinephrine system, the
type of
receptor may be, for example, norepinephrine pre-synaptic alpha-2 adrenergic
receptors. In
such cases, the ligand is a norepinephrine pre-synaptic alpha-2 adrenergic
receptor agonist.
Undesirable mental, neurological or physiological conditions are generally
positively
linked to the receptors. The counteradaptation may be an increase in the
biosynthesis
and/or release of norepinephrine at the synaptic cleft; a decrease in reuptake
of
norepinephrine; a decrease in the number of norepinephrine pre-synaptic alpha-
2
adrenergic receptors; a decrease in the sensitivity of the norepinephrine pre-
synaptic alpha-
2 adrenergic receptors to norepinephrine and/or norepinephrine pre-synaptic
alpha-2
adrenergic receptor agonists; an increase in the number of norepinephrine post-
synaptic
adrenergic receptors; an increase in the sensitivity of the norepinephrine
post-synaptic
adrenergic receptors to norepinephrine and/or norepinephrine post-synaptic
adrenergic
receptor agonists; or any combination thereof.
[00202] A variety of compounds may be used as the norepinephrine pre-synaptic
alpha-2 adrenergic receptor agonists in the methods of the present invention.
For example,
the norepinephrine pre-synaptic alpha-2 adrenergic receptor agonist may be
clonidine,
guanfacine, lofexidine, detomidine, dexmedetomidine, mivazerol, or alpha-
methylnoradreniline.
[00203] The initial dosage of the norepinephrine pre-synaptic alpha-2
adrenergic
receptor agonist is desirably high enough to induce a counteradaptive effect,
but not so
high as to cause the patient intolerable direct effects. For example, the
initial dosage may
be equivalent to between 0.1 and 10 g/kg/administration of clonidine, between
0.01 and
mg/administration guanfacine, between 0.01 and 1 mg/administration lofexidine,
between I and 100 g/kg/administration detomidine, between 0.05 and 5
gg/kg/administration dexmedetomidine, between 0.05 and 10 gg/kg/administration
mivazerol, or between 5 and 500 ng/kg/administration of alpha-
methylnoradreniline.
Desirably, the initial dosage is equivalent to between 0.1 and 0.5
mg/administration of
clonidine, between 0.1 and 5 mg/administration guanfacine, between 0.05 and
0.5
mg/administration lofexidine, between 10 and 80 j.Ig/kg/administration
detomidine,
between 0.1 and 3 g/kg/adrninistration dexmedetomidine, between 0.5 and 5
56
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
g/kg/administration of mivazerol, or between 10 and 100 ng/kg/administration
of alpha-
methylnoradreniline.
[00204] Desirably, a norepinephrine pre-synaptic alpha-2 adrenergic receptor
antagonist is not administered during the first time period associated with
each
administration. In certain embodiments of the invention, however, an
norepinephrine pre-
synaptic alpha-2 adrenergic receptor antagonist is administered during one or
more of the
second time periods. A suitable non-limiting example of a pre and postsynaptic
A2AR
antagonist includes mirtazapine.
[00205] According to another embodiment of the invention, the type of receptor
is
norepinephrine post-synaptic adrenergic receptors, such as alpha receptors,
beta receptors,
or receptors of a subtype thereof. In such cases, the ligand is a
norepinephrine post-
synaptic adrenergic receptor antagonist. Undesirable mental, neurological or
physiological
conditions are generally negatively linked to the norepinephrine post-synaptic
adrenergic
receptors. The counteradaptation may be an increase in the biosynthesis or
release of
norepinephrine at the synaptic cleft; a decrease in the reuptake of
norepinephrine; an
increase in the number of norepinephrine post-synaptic adrenergic receptors;
an increase in
the sensitivity of the norepinephrine post-synaptic adrenergic receptors to
norepinephrine
andlor norepinephrine post-synaptic adrenergic receptor agonists; a decrease
in the number
of norepinephrine pre-synaptic alpha-2 adrenergic receptors; a decrease in the
sensitivity of
the norepinephrine pre-synaptic alpha-2 adrenergic receptors to norepinephrine
and/or
norepinephrine pre-synaptic alpha-2 adrenergic receptor agonists; or any
combination
thereof.
[00206] A variety of compounds may be used as the norepinephrine post-synaptic
adrenergic receptor antagonists in the methods of the present invention. For
example, the
norepinephrine post-synaptic adrenergic receptor antagonist may be idazoxan,
SKF
104078, or SKF 104856. The initial dosage of the norepinephrine post-synaptic
adrenergic
receptor antagonist is desirably high enough to induce a counteradaptive
effect, but not so
high as to cause the patient intolerable direct effects. For example, the
initial dosage may
be equivalent to between 0.5 and 100 mg/administration of idazoxan. Desirably,
the initial
dosage is equivalent to between 5 and 50 mg/administration of idazoxan.
[00207] Desirably, a norepinephrine post-synaptic adrenergic receptor agonist
is not
administered during the first time period associated with each administration.
In certain
57
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
embodiments of the invention, however, a norepinephrine post-synaptic
adrenergic
receptor agonist is administered during one or more of the second time
periods.
[00208] The norepinephrine post-synaptic adrenergic receptor antagonist may be
administered in combination with a norepinephrine pre-synaptic alpha-2
adrenergic
receptor agonist, such as those described above. Further, when conventional
anti-
depressant agents that bind at the norepinephrine post-synaptic adrenergic
receptors are
given in combination with a norepinephrine pre-synaptic alpha-2 adrenergic
receptor
agonist, its efficacy can be greatly increased because the norepinephrine post-
synaptic
adrenergic receptors have increased in number and/sensitivity through the
counteradaptation.
[00209] In certain desirable embodiments of the invention, the norepinephrine
post-
synaptic adrenergic receptor antagonist itself is also an norepinephrine pre-
synaptic alpha-2
adrenergic receptor agonist. It may also be desirable to administer a
serotonin post-
synaptic antagonist and/or a serotonin pre-synaptic autoreceptor agonist (as
described
above) in combination with the norepinephrine pre-synaptic alpha-2 adrenergic
receptor
agonist or norepinephrine post-synaptic adrenergic receptor antagonist.
[00210] Norepinephrine post-synaptic adrenergic receptors are generally
negatively
linked, and norepinephrine pre-synaptic alpha-2 adrenergic receptors are
generally
positively linked to a wide variety of undesirable mental and neurological
conditions.
Examples of such conditions include pain, mood disorders, eating disorders,
anxiety
disorders, obsessive-compulsive disorders, motivational problem, substance
abuse
disorders, insufficient motivation or performance, pain that is expected to
occur in the
future (e.g., due to, a future operation or future physical exertion), chronic
pain syndromes,
acute pain, fibromyalgia, chronic fatigue syndrome, chronic back pain, chronic
headaches,
shingles, reflex sympathetic dystrophy, neuropathy, inflammatory pain, chronic
cancer
pain, major depressive disorders, post traumatic depression, temporary
depressed mood,
manic-depressive disorders, dysthymic disorders, generalized mood disorders,
anhedonia,
non-organic sexual dysfunction, overeating, obesity, anorexia, bulimia,
generalized anxiety
state, panic disorders, Tourette's Syndrome, hysteria sleep disorders,
breathing-related
sleep disorders, lack of motivation due to learning or memory problems, abuse
of
substances such as narcotics, alcohol, nicotine, stimulants, anxiolytics, CNS
depressants,
hallucinogens and marijuana, and insufficient motivation or preparation for a
desired
58
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
mental or physical activity such as physical training, athletics, studying or
testing. The up-
regulation of the norepinephrine system desirably causes a therapeutic benefit
with respect
to the undesirable mental, neurological or physiological condition.
THE CRF SYSTEM
[00211] The hypothalamic-pituitary-adrenal (HPA) axis is the regulatory
mechanism
by which the body responds to stress. The hypothalamus is a general control
center for
many of the body's hormones. In response to stress the hypothalamus releases
corticotropin releasing factor (CRF, also known as corticotropin releasing
hormone), which
reaches the anterior pituitary gland and induces changes that release the
hormone ACTH
(adrenocorticotropic hormone) and beta-endorphin into the circulation. ACTH
reaches the
adrenal glands, which are located adjacent to the kidneys, and simulates the
release of
cortisol. Cortisol release into the circulation initiates a series of
metabolic effects that
alleviate the harmful effects of stress. There is also a negative feedback to
both the
hypothalamus and the anterior pituitary which shuts off further cortisol
release.
[00212] Besides CRF release from the hypothalamus, CRF is present in many
other
areas of the cortex. When it is released from the hypothalamus it acts as a
hormone. In the
cortex the CRF molecule acts as a neurotransmitter. Neurotransmitter effects
of the CRF
results in some of the behavioral effects that are common in depression. Some
of these
effects are due to the CRF effect on other neurotransmitter systems, such as
the serotonin
and norepinephrine (NE) systems. The CRF relation to depression is thus quite
complex
and relates to its effects on the HPA axis as well as direct effects on the
brain and on other
neurotransmitter systems.
[00213] CRF is a 41 amino acid peptide. It was first isolated and sequenced by
Vale
in 1981 (Vale W, Spiess J, Rivier C, Rivier J(19S 1): Characterization of a 41-
residue ovine
hypothalamic peptide that stimulates secretion of corticotropin and j3-
endorphin. Science
213:1394-1397). The sequence of CRF has been detertnined in a variety of
species,
including sheep, man, rats, pigs, goats and cows. In all species, CRF is a 41-
amino acid
residue single chain polypeptide. Rat and human CRF are identical to one
another and
differ from ovine CRF by seven amino acid residues. All three CRFs have close
amino acid
homology and share some biologic properties with sauvagine, a 40-amino acid
peptide that
exists in frog skin, and urotensin 1, a 41-amino acid peptide derived froni
fish urophysis.
Caprine and ovine CRF are identical and differ from bovine CRF by one amino
acid.
59
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
Porcine CRF more closely resembles rat/human CRF. CRF, and related peptides,
are
amidated at their carboxy terminal; CRF COOH-terminal-free acid has less than
0.1 % of
the potency of native CRF, suggesting the importance of amidation to the
biological
activity of the peptide. Studies to determine the solution structure of CRF
using proton
nuclear magnetic resonance spectroscopy suggest that human CRF comprises an
extended
N-terminal tetrapeptide connected to a well-defined a-helix between residues 6
to 36. An
a-helical oCRF(9-41) is an antagonist of CRF, which underscores the necessity
of the a-
helical conformation for receptor binding and biological activity. (Errol B.
De Souza and
Dimitri E. Grigoriadis, Corticotropin-Releasing Factor: Physiology,
Phannacology and
Role in Central Nervous System and Immune Disorders, Psychopharmacology -
Fourth
Generation of Progress, 2000, http://www.acnp.org/g4/GN401000049/CH049.htm1)
[00214] Mood, mood disorders and related conditions are a result of a complex
web
of central nervous system events that interrelate many neurotransmitter
systems. A most
common mood disorder is depression. Depression is a clinical diagnosis with
numerous
somatic and mental symptoms, which is due to an alteration of numerous
neurotransmitter
systems. Beisdes the CRF system other systems associated with depression are
the
norepinephrine, serotonin, substance P, dynorphin (kappa receptors), and the
endogenous
endorphin (mu and delta opiate receptors) systems. Further, these
neurotransmitter systems
are also related to a whole host of other undesirable mental and neurological
conditions,
including bipolar disorders, obsessive-compulsive disorders, anxiety, phobias,
stress
disorders, substance abuse, sexual disorders, eating disorders, motivational
disorders and
pain disorders.
[00215] Stress is felt to be a major cause of depression and anxiety in the
adult.
Whether or not an individual actually becomes clinically depressed also
depends on the
genetic predisposition to depression and any major early life stressful
situations (Lott,
Psychiatric Times 1999 Oct; Vol. XVI, Issue 10.).
[00216] The HPA axis plays a major role in depression and anxiety disorders
because of its role in stressful situations. It is well established that CRF
levels are
increased in depression (ie., melancholic depression, but not atypical
depression - see
below). Cortisol levels are also generally increased in depression. This is
due to a hyper
activity of the HPA axis, largely thought to be due to an impairment of the
negative
inhibition loop. In other words, the persistent release of CRF and its
persistent elevation in
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
the circulation, which may be a result of chronic stressful situations, is not
inhibited by the
elevated cortisol levels, as would occur in the normal, non-depressed
individual.
[00217] Depression studies generally categorize all patients into one
category.
There are however different forms of depression, which tend to have different
regulatory
changes in the HPA axis. There are two notable subtypes of depression,
melancholic and
atypical. Melancholic depression is the most common form of depression.
Melancholic
patients are generally anxious, dread the future, lose responsiveness to the
environment,
have insomnia, lose their appetite (weight loss), and a diurnal variation with
depression at
its worst in the morning. Atypical patients are generally opposite in many of
these areas.
Atypical patients generally are lethargic, fatigued, hyperphagic (weight
gain),
hypersomnic, reactive to the environment, and show diurnal variation of
depression that is
at its best in the morning. (Gold, et al, "Organization of the stress system
and its
dysregulation in melancholic and atypical depression: high vs. low CRH/ NE
states." Mol
Psychiatry, 2002; 7(3):254-75.")
[00218] Melancholic patients are characterized by a hyperactive central CRH
system
with over-activity of'the HPA axis. On the other hand, atypical depression is
characterized
by a hypo-active central CR H system and an under-activity of the HPA axis.
(Kasckow,
JW, et al, "Corticotropin-releasing hormone in depression and post-traumatic
stress
disorder." Peptides, 2001 May; 22(5):845-51.) Atypical depression is thought
to be due to
hyper-suppression of the HPA axis. It may be associated with an exaggerated
negative
feedback regulation of the HPA axis. (Levitan R.D, "Low-dose dexamethasone
challenge
in women with atypical major depression: pilot study." J Psych Neurosci, 2002
Jan;
27(1):47-51)
[00219] Post-traumatic stress disorder (PTSD) is a third category and it is
also
unique. PTSD is characterized by a hyperactive central CRH system as in
melancholic
depression, but there is under-activity of the HPA axis as in atypical
depression. (Levitan,
2002)
[00220] Anxiety disorders have a different pattern of HPA axis changes than
does
melancholic depression. Depression is characterized by a hypercortisolemia,
non-
suppression after dexamethasone and a decrease in the number of glucocorticoid
receptors.
Anxiety is characterized by hypo-cortisolemia, super-suppression after
dexamethasone and
an increase in the number of glucocorticoid receptors. (Boyer, P, "Do anxiety
and
61
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
depression have a common pathophysiological mechanism?" Acta Psychiatr Scand
Suppl
2000; (406):24-9)
(00221] Eating disorders are largely related to mood and/ or stress. Dallman
et al.,
(Chronic stress and obesity: a new view of "comfort food". Proc Natl Acad Sci
USA 2003
Sep 30; 100(20):11696-701) demonstrate that, although rats generally decrease
weight in
response to chronic stress, chronic stress in humans induces either increased
comfort food
intake and body weight gain or decreased intake and body weight loss. As
discussed above
melancholic depression tends to be associated with poor appetite and weight
loss and
atypical depression tends to be associated with increased eating and weight
gain.
[00222] Conventional strategies for treating neurotransmitter-linked
conditions are
centered on improving abnormally high or low levels of synaptic
neurotransmitters.
Conventional therapeutic agents work to directly regulate the functioning of
the
neurotransmitter systems. Such agents may be anxiolytic agents, hypnotic
agents, or
selective reuptake inhibitors, and include benzodiazepines (e.g., diazepam,
lorazepam,
alprazolam, temazepam, flurazepam, and chlodiazepoxide), TCAs, MAOls, SSRIs
(e.g.,
fluoxetine hydrochloride), NRIs, SNRIs, serotonin pre-synaptic autoreceptor
antagonists,
SHTI agonist, GABA-A modulating agents, serotonin 5H2c and/or 5H2B modulating
agents,
beta-3 adrenoceptor agonists, NMDA antagonists, V1B antagonists, GPCR
modulating
agents, dynorphin antagonists, and substance P antagonists. CRF antagonists
are thought
to be the next class of antidepressants (Nielsen, Life Sci, 2006, Jan 25;
78(9): 909-19.).
j00223] With respect to the CRF system, because of the different HPA axis
changes
with different types of depression, the response to pharmaceutical agents is
expected to
vary, depending on the type of depression or anxiety disorder that is being
treated. Indeed,
antidepressants that are effective in decreasing CRH production, ie. TCAs,
have good
efficacy for melancholic depression. These same agents are not particularly
effective for
the treatment of atypical depression, which is not associated with activation
of the CRH-
producing system, but rather to a decrease in CRH secretion. (Licinio, J, et
al, "Role of
corticotrophin releasing hormone 41 in depressive illness." Baillieres Clin
Endocrinol
Metab, 1991 Mar; 5(1):51-8.)
[00224] Numerous studies have indicated the potential of CRF antagonists as
antidepressants (O'brien, Hum Psychopharmacol, 2001, Jan; 16(1): 81-87 and
Arborelius,
et al, J Endocrinol 1999, 160: 1-12). Because they block the effects of a
hyper-active CRF
62
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
system, CRF antagonists are thought to be indicated for conditions that have a
hyper-active
CRF system, such as melancholic depression, rather than for atypical
depression, which has
a hypo-active CRF system.
[00225] Beta-endorphin is an endogenous opiate compound that is beneficial
during
a stress response. It reduces the sensation of pain. Endorphins are the result
of an
evolutionary mechanism which ensures that survival comes first, and
recuperation comes
later. Pain would ordinarily produce behaviors that would hurt the chances of
survival. For
instance, if an animal is attacked and stops to lick its wounds instead of
fleeing away from
its attacker, the animal's life is put in danger. But, fear triggers the
release of endorphins
which that inhibit the perception of pain. Furthermore, endorphins have an
effect on the
immune system that better helps ward off infection, which is advantageous, had
the animal
been injured.
[002261 Beta endorphin is closely associated with the HPA. In addition to its
actions
on areas in the cortex of the brain, such as improving pain response, beta
endorphin also
regulates the release of CRF through a negative inhibition at the
hypothalamus. (fig. X)
[00227] Beta endorphin and endogenous opioid peptides in general inhibit the
HPA
by decreasing the release of CRF (Burnett, J Affect Disord 1999 Jun; 53(3):
263-8.). This
latter study demonstrates that there is decreased inhibitory opioid tone in
depressed
individuals. In other words there is a down regulation of the beta endorphin
system in
depressed individuals. This is corroborated by other studies which demonstrate
that
depression is associated with decreased circulating levels of beta endorphin
(Cohen, AM J
Psychiatry 1984; 141: 629-32., and Djurovic, Farmaco 1999 Mar 31; 54(3): 130-
3.).
[00228] Beta endorphins were also demonstrated to be increased in depressed
individuals (Goodwin, J Affect Disord 1993 Dec; 29(4): 281-9). Although this
finding
seems to contradict the above studies, wehre endorphin levels are decreased in
depression,
this latter study is actually consistent with the above studies. This is
explained as follows.
In the latter study (Goodwin), beta endorphin was actually negatively
correlated with the
severity of depression symptoms, which is consistent with the fact that down
regulation of
beta endorphin is associated with depression, and the above studies (Cohen &
Djurovic).
The Goodwin study demonstrates that an acute psychosocial precipitant can
increase beta
endorphin levels acutely. This indicates that acute stressful events can cause
such an
increase in CRF that it can override the down regulated beta endorphin system.
However,
63
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
the Goodwin study also confirms the fact that there is a general down
regulation of beta
endorphin with depression, and that the severity of depression is inversely
correlated with
the levels of circulating beta endorphins, just as was demonstrated by the
Cohen and
Djurovic studies. In sunulaary, although beta endorphins may be acutely
elevated in
depressed individuals who are subjected to a stressful precipitating event, on
a daily steady
state level depressed patients have lower than normal levels of circulating
endorphins.
[00229] The Butnett (1999) study summarizes that some clinically depressed
individuals may self-medicate with opiates. In those situations the opiates
replace the
`missing' or down regulated endogenous endorphins. These self-administered
opiates
perform the same task as do endogenous endorphins, which are meant to inhibit
the HPA,
thereby decreasing CRF release.
[00230] Because hyperactivity of the HPA is associated with depression the use
of
CRF antagonists has recently been advocated for the treatment of depression.
There are
certain limitations to the use of CRF antagonists for the treatment of
depression.
[00231 ]_ Accordingly, in one embodiment of the invention, the
neurotransmitter
system is the CRF system which includes corticotropin releasing factor as a
neurotransmitter, the type of receptor is CRF receptors, the ligand is a CRF
receptor
agonist, and the counteradaptation causes a down-regulation of the CRF system.
Regulation of the CRF system via counteradaptation is described in U.S.
Provisional Patent
Application serial number 60/777,190, entitled "METHOD OF REGULATING THE CRF
AND AVP SYSTEMS BY INDUCING COUNTERADAPTATIONS," and filed on
February 27, 2006.
[00232] The CRF receptor may be, for example, CRF-1 or CRF-2. CRF-1 is
generally associated with mood, while CRF-2 is generally associated with
memory.
[00233] CRF agonists have effects on both the HPA and the extra-hypothalamic
systems. With respect to the HPA, a CRF agonist causes the release of ACTH and
beta
endorphin into the circulation. In the near-term setting (i.e., during the
first time period
associated with each administration), the release of beta endorphin is
beneficial because
endorphins are known to improve hyperactive C12F conditions, such as
depression and
anxiety. But the CRF agonist would also increase ACTH release, which would
have the
effect of increasing cortisol release in the near-term. The elevation of
cortisol is not what
64
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
is needed when the goal is to depress the activity of a hyperactive CRF
system.
Furthermore, the agonist directly acts on the extra-hyphthalamic CRF system.
Together,
the effects on the ACTH release and on extra-hypothalamic CRF and AVP systems
result
in the wor'sening of the hyper-active CRF state in the near term. However,
according to the
present invention, the method described herein cause a counteradaptation, and
an overall
down-regulation of the CRF system, for example through down-regulation of ACTH
relase
and down-regulation of the extra-hypothalamic CRF system.
[00234] The counteradaptation may be a decrease in the biosynthesis or release
of
corticotropin releasing factor by the hypothalamus; a decrease in the number
of the CRF
receptors and/or binding sites on the CRF receptors; a decrease in the
sensitivity of the
receptors to binding by CRF receptor agonists and/or corticotropin releasing
factor; or any
combination thereof.
[00235] A variety of compounds may be used as CRF receptor agonists. For
example, a number of peptide-based compounds are CRF receptor agonists.
Examples
include analogs of corticotrophin releasing factor and pharmaceutically
acceptable salts and
derivatives thereof. Cortagine is a suitable CRF receptor agonist for use in
the methods of
the present invention, described in Tezval, et al, PNAC, 101(25) (2004) and
Todorovic, C.,
et al., Neurosci Biobehav Rev., 2005, 29(8): 1323-1333, each of which is
incorporated
herein by reference. Examples of CRF receptor agonists are described further
in U.S.
Patents 5,132,111; 5,278,146; 5,824,771; 5,844,074; 6,214,797; 6,670,371;
6,812,210;
6,953,838, each of which is hereby incorporated by reference herein.
[00236] The initial dosage of the CRF receptor agonist is desirably high
enough to
induce a counteradaptive effect, but not so high as to cause the patient
intolerable direct
effects. For example, the initial dosage may be about 0.1 to 100 g/kg/day
initial dose and
100 to 1000 [+.g/kg/day for 8 hours slow release. In certain embodiments of
the invention,
the initial dosage of the CRF receptor agonist is between about 1 to 50
g/kg/day initial
dose and 20 to 50 g/kg/day for 8 hours slow release.
[00237] Desirably, neither a CRF receptor antagonist nor an AVP receptor
antagonist is administered during the first time period associated with each
administration
of the CRF receptor agonist. In certain embodiments of the invention, however,
a CRF
receptor antagonist and/or an AVP receptor antagonist is administered during
one or more
of the second time periods associated with each administration of the CRF
receptor agonist.
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
(00238] Examples of CRF antagonists include R121919 (Zobel, J Psychiatr Res
2000 May-Jun; 34(3): 171-81), DMP696 (Maciag, Neuropsychopharmacol 2002; 26:
574-
582), antalarmin (Willenberg, Mol Psychiatry 2000 Mar; 5(2): 137-41), CP-
154,526
(Mansbach, Eur J Pharmacol 1997 Mar 26; 323(1): 21-6), SSR125543A (Briebel, J
Pharmacol Exp Ther 2002 Apr; 301(1): 333-45), 2-arylamino-4-trifluoromethyl-
aminomethylthiazole antagonists (Dubowchik, Bioorg Med Chem Lett 2004 Nov 17;
13(22): 3997-4000), and astressin (Spina, Neuropsychopharmacol =2000; 22: 230-
239), and
pharmaceutically acceptable salts, analogues and derivatives thereof.
[002391 Examples of AVP receptor antagonists include peptidic AVP receptor
antagonists such as d(CH2)STyr(Me)AVP, Phaa-d-Tyr(Me)-Phe-Gln-Asn-Arg-Pro-Arg-
Tyr-NH2, [Lys(3N3 Phpa)g]HO-LVA, [d(CH2)5, D-Ile2, Ile4]-AVP, and [1251]-
d(CH2)5[D-Tyr(Et)2, Va14, Tyr-NH29) AVP, and any analog of the AVP peptide
(Cys-
Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly) that has AVP antagonist activity. AVP peptide
antagonists may further include any pro-peptide molecule that is enzymatically
cleaved
into an active AVP antagonist. Examples of AVP receptor antagonists also
include non-
peptidic species such as OPC-21268 (1-(1-[4-(3-acetylaminopropoxy) benzoyl]-4-
piperidyl)-3,4-dihydro-2(1 H)-quinolinone), R 49059 (V 1 a antagonist), OPC-
31260 (5-
dimethylamino-l-[4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetra hydro-lH-
benzazepine), conivaptan (YM087 - a Vla and V2 antagonist), Vaprisol
(conivaptan)
(V 1 a and V2 antagonist), VPA 985 (V2 antagonist), and YM 471 [(Z)-4'-[4,4-
difluoro-5-
[2-(4-dimethylaminopiperidino)-2-oxoethylidene]-2,3,4,5-tetrahydro-1 H-1-
benzoazepine-
1-carbonyl]-2-phenylbenzanilide monohydrochloride]. AVP receptor antagonists
are also
described in U.S. Patents 6,627,649 and 6,495,542, each of which is hereby
incorporated
by reference in its entirety.
[00240] In another embodiment of the invention, a mu and/or delta opiate
receptor
antagonist is administered in combination with the CRF agonist during the
first time period
with a ratio of administration half-life to the period between administrations
no greater than
1/2. Administration methods for mu and/or delta opiate receptor antagonists
are described
hereinabove. This may be desirable due to the fact that the use of a CRF
agonist, although
intended to cause a down regulation of the CRF system, may have the unintended
consequence of also down regulating the release of beta endorphin from the
anterior
pituitary gland. Such a reduced endorphin release would induce the opposite
effect as to
what is needed for the improvement of undesirable conditions that correlate
inversely with
66
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
the levels of circulating endorphins, such as depression and anxiety
disorders. The
repeated administration of the opiate antagonist may have two important
effects: to block
the endorphin down regulation by the CRF agonist, and also to cause an up-
regulation of
the endorphin system as described above. The principles for the administration
of an
opiate antagonist in order to induce an up regulation of the endogenous
endorphin system
are as described hereinabove. As described above, it may also be desirable to
administer a
CRF and/or AVP antagonist during the second time period associated with each
administration of the CRF agonist. Desirably, neither a CRF receptor
antagonist nor an
AVP receptor antagonist is administered during the first time period
associated with each
administration.
[00241) CRF agonist administration according to this embodiment of the
invention
may be used to address an undesirable mental, neurological, or physiological
condition in a
patient, the undesirable mental, neurological or physiological condition being
positively
linked to CRF receptors. Examples of undesirable mental, neurological and
physiological
conditions that are positively linked to CRF receptors and addressable using
this method
include: melancholic depression, insufficient memory and a need for increased
memory
anticipated to occur in the future, anxiety and anxiety-related disorders,
poor appetite and
undereating disorders such as anorexia and bulimia, stress and stress that is
anticipated to
occur in the future, post-traumatic stress disorder, and a lack of motivation
due to learning
or memory problems. In desirable embodiments of the invention, the down-
regulation of
the CRF system causes a therapeutic benefit with respect to an undesirable
mental,
neurological or physiological condition positively linked to CRF receptors.
[00242] Intermittent administration of a CRF receptor agonist (with or without
intermittent administration of a mu and/or delta opiate receptor antagonist)
may be useful
in improving an individual's ability to deal with a stressful situation, when
such a situation
should arise in the future. This is explained by the fact that small amounts
of intermittent
stress are actually good for a living organism. Such small amounts of
intermittent stress
stimulate the proper adaptations which allow that organism to better be able
to deal with
stressful situations when they arise in the future. Intermittent stress
actually results in an
intermittent increase in cortisol levels. Such an intermittent increase in
cortisol levels is
also what happens with the intermittent administration of a CRF and/ or AVP
agonist.
Intermittent administration of a CRF receptor agonist thus mimics that which
occurs with
small amounts of intermittent stress. It induces a physiogical stress (i.e.,
increased CRF
67
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
release) in the individual on a near-term temporary basis, which is a small
enough `sress'
and of a short enough duration that it does not allow the side effects that
can occur with
chronic large stresses (i.e., hyperactive CRF and/or AVP systems). The method
is intended
to allow an individual to better be able to deal with a larger stress when it
does occur in the
future. In other words, a living organism that is subjected to a small amount
of intermittent
stress (i.e., temporarily increased CRF levels) will be better able to deal
with a large
amount of stress (i.e., large increase in CRF levels) in the future should
such a situation
arise, as compared to an organism that is never subjected to such short term
temporary
stress. When an acute stressful situation arises, it may be desirable to
administer a CRF
receptor antagonist and/or an AVP receptor antagonist during the second time
period
associated with each administration.
[00243] In another embodiment of the invention, the neurotransmitter system is
the
CRF system which includes corticotropin releasing factor as a
neurotransmitter, the type of
receptor is CRF receptors, the ligand is a CRF receptor antagonist, and the
counteradaptation causes a up-regulation of the CRF system. Regulation of the
CRF
system via counteradaptation is described in U.S. Provisional Patent
Application serial
number 60/777,190, entitled "METHOD OF REGULATING THE CRF AND AVP
SYSTEMS BY INDUCING COUNTERADAPTATIONS," and filed on February 27,
2006.
[00244] The CRF receptor may be, for example, CRF-1 or CRF-2. CRF-1 is
generally associated with mood, while CRF-2 is generally associated with
memory.
[00245] The counteradaptation may be an increase in the biosynthesis or
release of
corticotropin releasing factor by the hypothalamus; an increase in the number
of the CRF
receptors and/or binding sites on the CRF receptors; an increase in the
sensitivity of the
receptors to binding by CRF receptor agonists and/or corticotropin releasing
factor; or any
combination thereof.
[00246] Suitable CRF antagonists are described hereinabove. The initial dosage
of
the CRF receptor antagonist is desirably high enough to induce a
counteradaptive effect,
but not so high as to cause the patient intolerable direct effects. For
example, the initial
dosage may be about 0.1 to 100 gg/kg/day initial dose and 100 to 1000
g/kg/day for 8
hours slow release. In certain embodiments of the invention, the initial
dosage of the CRF
68
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
receptor antagonist is between about 1 to 50 g/kg/day initial dose and 20 to
50 g/kg/day
for 8 hours slow release.
[00247] Desirably, neither a CRF receptor agonist nor an AVP receptor agonist
is
administered during the first time period associated with each administration
of the CRF
receptor antagonist. In certain embodiments of the invention, however, a CRF
receptor
agonist and/or an AVP receptor agonist is administered during one or more -of
the second
time periods associated with each administTation of the CRF receptor
antagonist. Suitable
CRF receptor agonists and AVP receptor agonists are described hereinabove.
[00248] In another embodiment of the invention, a mu and/or delta opiate
receptor
antagonist is administered in combination with the CRF antagonist during the
first time
period with a ratio of administration half-life to the period between
administrations no
greater than 1/2. Administration methods for mu and/or delta opiate receptor
antagonists
and the benefits thereof are described hereinabove.
[00249] CRF antagonist administration according to these embodiments of the
invention may be used to address an undesirable mental, neurological, or
physiological
condition in a patient, the undesirable mental, neurological or physiological
condition
being negatively linked to CRF receptors. Examples of undesirable mental,
neurological
and physiological conditions that are negatively linked to CRF receptors and
addressable
using this method include, for example, atypical depression, weight gain and
overeating
disorders, lethargy and fatigue. In desirable embodiments of the invention,
the up-
regulation of the CRF system causes a therapeutic benefit with respect to an
undesirable
mental, neurological or physiological condition negatively linked to CRF
receptors.
THE AVP SYSTEM
[00250] AVP is a hormone, also called ADH (antidiuretic hormone) that is a
nona-
peptide (Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly) with a cyclic structure, formed
through a
disulfide bridge between the two cysteine residues. AVP is the active honnone
that is
initially synthesized as a propeptide, ppAVP, which is 164 amino acids in
l.ength. The
biologically active portion is AVP(20-28). The AVP nonapeptide is in certain
instances
further broken down into smaller biologically active fragments, ie., AVP(4-9),
AVP(4-8),
AVP(5-9), AVP 5-8). These smaller fragments lack peripheral endocrine
activity, but do
demonstrate selective activity within the CNS.
69
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
(002511 AVP hormone is produced by the hypothalamus, just as is CRF (and
several
other relasing factors). AVP is, however, produced from different secretory
bodies than
those which produce the releasing factors such as CRF (which flow directly to
the anterior
pituitary gland). The posterior pituitary gland is actually an extension of
the hypothalamus.
The AVP-producing cell bodies are in the hypothalamus. From the cell bodies
the AVP is
transported to the axonal terminals of these neuronal cell bodies, which is
located in the
posterior pituitary. From the posterior pituitary the AVP is released into the
circulation.
[00252] In the circulation the AVP has two basic actions, peripheral and
central.
The peripheral actions pertain to vasoconstriction, glycogen metabolism and
antidiuresis.
The central actions pertain to learning and memory, social behaviors,
thermoreguloation,
autonomic function and mood.
[00253] AVP acts synergistically with CRF to stimulate the release of ACTH
from
the anterior pituitary. AVP also has direct effects on the adrenals for the
release of cortisol.
AVP has a similar effect on beta endorphin as does CRF, it stimulates beta
endorphin
release from the anterior pituitary gland.
[00254] AVP plays a role in stress and thus in depression and anxiety. Just as
certain mood disorders (ie., depression and anxiety) are associated with a
hyper-active CRF
system, depression and anxiety are also associated with a hyper-active AVP
system. AVP
antagonists acting at the Vlb receptor have demonstrated early favorable
results as
potential antidepressant and anxiolytic agents in animal studies. In addition,
antagonists
acting at the V 1a receptor may also play a role as antidepressants and
anxiolytics.
[00255] Accordingly, in one embodiment of the invention, the neurotransrnitter
system is the AVP system which includes corticotropin releasing factor as a
neurotransmitter, the type of receptor is AVP receptors, the ligand is an AVP
receptor
agonist, and the counteradaptation causes a down-regulation of the AVP system.
Regulation of the AVP system via counteradaptation is described in U.S.
Provisional Patent
Application serial number 60/777,190, entitled "METHOD OF REGULATING THE CRF
AND AVP SYSTEMS BY INDUCING COUNTERADAPTATIONS," and filed on
February 27, 2006.
[00256] The AVP receptors may be, for example, V 1 R (also known as V 1 a),
V2R or
V3R (also known as V lb). V3R is the primary receptor in the pituitary. VIR is
primarily
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
in the liver and the brain, while V2R is primary in the kidney. In desirable
embodiments of
the invention, the AVP receptors are VIR receptors or V3R receptors.
[00257] The counteradaptation may be a decrease in the biosynthesis or release
of
arginine vasopressin by the hypothalamus; a decrease in the number of the AVP
receptors
and/or binding sites on the AVP receptors; a decrease in the sensitivity of
the receptors to
binding by AVP receptor agonists and/or arginine vasopressin; or any
combination thereof.
[00258] A variety of compounds may be used as AVP receptor agonists. For
example, a number of peptide-based compounds are AVP receptor agonists.
Peptides may
by synthetic or from mammal sources, such as bovine or porcine or others.
Peptides may
be linear or cyclic. Suitable peptidic AVP agonists include, for example,
felypressin (2-L-
Phe-8-L-lys AVP), desmopressin (1-(30mercaptopropionic acid)-8-D-AVP) and any
peptide analog of the AVP peptide (Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly) that
has AVP
agonist activity. AVP peptide agonists may further include any pro-peptide
molecule that
is enzymatically cleaved into an active AVP agonist. AVP peptide agonists may
further
include any compounds that contain the smaller biologically active fragments
of the AVP
nonapeptide, such as AVP(4-9), AVP(4-8), AVP(5-9), AVP (5-8). Other AVP
receptor
agonists suitable for use in the present invention include those disclosed in
U.S. Patents
6,090,803; 6,096,735; 6,096,736; 6,194,407; 6,235,900; 6,268,360; 6,297,234;
6,335,327; 6,344,451; 6,620,807; 6,642,223; and 6,831,079, each of which is
incorporated herein by reference. As the skilled artisan will appreciate,
pharmaceutically
acceptable salts or derivatives of the above-described AVP agonists may also
be used in the
methods of the present invention.
[00259] The initial dosage of the AVP receptor agonist is desirably high
enough to
induce a counteradaptive effect, but not so high as to cause the patient
intolerable direct
effects. For example, the initial dosage may be about 0.1 to 100 g/kg/day
initial dose and
100 to 1000 g/kg/day for 8 hours slow release. In certain embodiments of the
invention,
the initial dosage of the AVP receptor agonist is between about I to 50
g/kg/day initial
dose and 20 to 50 g/kg/day for 8 hours slow release.
[00260] Desirably, neither a CRF receptor antagonist nor an AVP receptor
antagonist is administered during the first time period associated with each
administration
of the CRF receptor agonist. In certain embodiments of the invention, however,
a CRF
receptor antagonist and/or an AVP receptor antagonist is administered during
one or more
71
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
of the second time periods associated with each administration of the CRF
receptor agonist.
CRF receptor antagonists and AVP receptor antagonists are described
hereinabove.
[00261] In another embodiment of the invention, a mu and/or delta opiate
receptor
antagonist is administered in combination with the AVP agonist during the
first time period
with a ratio of administration half-life to the period between administrations
no greater than
1/2. Administration methods for mu and/or delta opiate receptor antagonists
are described
hereinabove. This may be desirable due to the fact that the use of an AVP
agonist,
although intended to cause a down regulation of the AVP system, may have the
unintended
consequence of also down regulating the release of beta endorphin from the
anterior
pituitary gland. Such a reduced endorphin release would induce the opposite
effect as to
what is needed for the improvement of undesirable conditions that correlate
inversely with
the levels of circulating endorphins, such as depression and anxiety
disorders. The
repeated administration of the opiate antagonist may have two important
effects: to block
the endorphin down regulation by the AVP agonist, and also to cause an up-
regulation of
the endorphin system as described above. The principles for the administration
of an
opiate antagonist in order to induce an up regulation of the endogenous
endorphin system
are described hereinabove. As described above, it may also be desirable to
administer a
CRF and/or AVP antagonist during the second time period associated with each
administration of the AVP agonist. Desirably, neither a CRF receptor
antagonist nor an
AVP receptor antagonist is administered during the first time period
associated with each
administration.
[00262] AVP agonist administration according to these embodiments of the
inveniion may be used to address an undesirable mental, neurological, or
physiological
condition in a patient, the undesirable mental, neurological or physiological
condition
being positively linked to AVP receptors. Examples of undesirable mental,
neurological
and physiological conditions that are positively linked to AVP receptors and
addressable
using this method include: melancholic depression, insufficient memory and a
need for
increased memory anticipated to occur in the future, anxiety and anxiety-
related disorders,
poor appetite and undereating disorders such as anorexia and bulimia, stress
and stress that
is anticipated to occur in the future, post-traumatic stress disorder, and a
lack of motivation
due to Iearning or memory problems. In desirable embodiments of the invention,
the
down-regulation of the AVP system causes a therapeutic benefit with respect to
an
72
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
undesirable mental, neurological or physiological condition positively linked
to AVP
receptors.
[00263] Intermittent administration of a AVP receptor agonist (with or without
intermittent administration of a mu and/or delta opiate receptor antagonist)
may be useful
in improving an individual's ability to deal with a stressful situation, when
such a situation
should arise in the future. This is explained by the fact that small amounts
of intermittent
stress are actually good for a living organism. Such small amounts of
intermittent stress
stimulate the proper adaptations which allow that organism to better be able
to deal with
stressful situations when they arise in the future. Intermittent stress
actually results in an
intermittent increase in cortisol levels. Such an intermittent increase in
cortisol levels is
also what happens with the intermittent administration of an AVP receptor
agonist.
Intermittent administration of an AVP receptor agonist thus mimics that which
occurs with
small amounts of intermittent stress. It induces a physiogical stress (i.e.,
increased AVP
release) in the individual on a near-term temporary basis, which is a small
enough `sress'
and of a short enough duration that it does not allow the side effects that
can occur with
chronic large stresses (i.e., hyperactive CRF and/or AVP systems). The method
is intended
to allow an individual to better be able to deal with a larger stress when it
does occur in the
future. In other words, a living organism that is subjected to a small amount
of intermittent
stress (i.e., temporarily increased AVP levels) will be better able to deal
with a large
amount of stress (i.e., large increase in AVP levels) in the future should
such a situation
arise, as compared to an organism that is never subjected to such short term
temporary
stress. When an acute stressful situation arises, it may be desirable to
administer a CRF
receptor antagonist and/or an AVP receptor antagonist during the second time
period
associated with each administration.
[00264] In another embodiment of the invention, the neurotransmitter system is
the
AVP system which includes corticotropin releasing factor as a
neurotransmitter, the type of
receptor is AVP receptors, the ligand is an AVP receptor antagonist, and the
counteradaptation causes a up-regulation of the AVP system. Regulation of the
AVP
system via counteradaptation is described in U.S. Provisional Patent
Application serial
number 60/777,190, entitled "METHOD OF REGULATING THE CRF AND AVP
SYSTEMS BY INDUCING COUNTERADAPTATIONS," and filed on February 27,
2006.
73
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00265] The AVP receptors may be, for example, V1R (also known as Vla), V2R or
V3R (also known as Vlb). V3R is the primary receptor in the pituitary. VIR is
primarily
in the liver and the brain, while V2R is primary in the kidney. In desirable
embodiments of
the invention, the AVP receptors are V 1 R receptors or V3R receptors.
[00266] The counteradaptation may be an increase in the biosynthesis or
release of
corticotropin releasing factor by the hypothalamus; an increase in the number
of the AVP
receptors and/or binding sites on the AVP receptors; an increase in the
sensitivity of the
receptors to binding by AVP receptor agonists and/or arginine vasopressin; or
any
combination thereof. '
[00267] Suitable AVP antagonists are described hereinabove. The initial dosage
of
the AVP receptor antagonist is desirably high enough to induce a
counteradaptive effect,
but not so high as to cause the patient intolerable direct effects. For
example, the initial
dosage may be about 0.1 to 100 g/kg/day initial dose and 100 to 1000
g/kg/day for 8
hours slow release. In certain embodiments of the invention, the initial
dosage of the AVP
receptor antagonist is between about I to 50 g/kg/day initial dose and 20 to
50 g/kg/day
for 8 hours slow release.
[00268] Desirably, neither a CRF receptor agonist nor an AVP receptor agonist
is
administered during the first time period associated with each administration
of the AVP
receptor antagonist. In certain embodiments of the invention, however, a CRF
receptor
agonist and/or an AVP receptor agonist is administered during one or more of
the second
time periods associated with each administration of the CRF receptor
antagonist. Suitable
CRF receptor agonists and AVP receptor agonists are described hereinabove.
[00269] AVP antagonist administration according to this embodiment of the
invention may be used to address an undesirable mental, neurological, or
physiological
condition in a patient, the undesirable mental, neurological or physiological
condition
being negatively linked to AVP receptors. Examples of undesirable mental,
neurological
and physiological conditions that are negatively linked to AVP receptors and
addressable
using this method include, for example, atypical depression, weight gain and
overeating
disorders, lethargy and fatigue, In desirable embodiments of the invention,
the up-
regulation of the AVP system causes a therapeutic benefit with respect to an
undesirable
mental, neurological or physiological condition negatively linked to AVP
receptors.
74
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
[00270] In another embodiment of the invention, a mu and/or delta opiate
receptor
antagonist is administered in combination with the AVP antagonist during the
first time
period with a ratio of administration half-life to the period between
administrations no
greater than 1/2. Administration methods for mu and/or delta opiate receptor
antagonists
and the benefits thereof are described hereinabove.
IMMUNE-SYSTEM RELATED CONDITIONS
[00271] The methods of the present invention are useful in addressing andror
treating immune system-related conditions which are linked to receptors of the
type of
receptors of the neurotransmitter system. In these methods, the immune system
is up-
regulated. Examples of immune system-related conditions that may be treated or
addressed
using the methods of the present invention include: cancer, especially cancers
having
cancer cells substantially free of zeta receptors; autoimmune disorders,
congenital immune
deficiency, immune deficiencies due to immunosuppressant therapy, and acquired
immune
deficiencies. Examples of particular autoimmune disorders include: xheumatoid
arehritis,
multiple sclerosis, systemic lupus erythematosus, Addison's disease, ALS (Lou
Gehrig's
Disease), Alzheimer's Disease, Ankylosing Spondylitis, Autism Spectrum
Disorders,
Autoimmune Hemolytic Anemia, Autoimmune Progesterone Dermatitis, Behcet's
Disease,
Celiac Disease, Chronic Fatigue Syndrome, Churg-Strauss (allergic
granulomatosis),
CREST syndrome, Crohn's Disease, Dermatomyositis, Diabetes Mellitus, Emphysema
(COPD), Endometriosis, Fibromyalgia, Goodpasture's disease, Graves disease,
Hashimoto's thyroiditis, Interstitial Granulomatous Dermatitis, Irritable
Bowel Syndrome
(IBS), Mixed Connective Tissue Disease, autoimmune-related connective tissue
disorders,
Myasthenia Gravis, Parkinson's Disease, Pemphigoid, Pernicious Anemia, Primary
Lateral
Sclerosis (PLS), Polychondritis (Relapsing), Polymyalgia Rheumatica,
Polymyositis,
Psoriasis, Sarcoidosis, Scleroderma, Sjogren's syndrome,Transverse Myelitis,
Ulcerative
Colitis, Vasculitis, Wegener's Granulomatosis, and autoimmune disorders
secondary to
infectious processes, administration of vaccines or environmental reactions
(e.g., to
chemicals such as silicones). According to one embodiment of the invention,
the
condition addressed by the method is the likelihood of becoming infected with
an
infectious microbe, such as a bacteria, fungus, parasite, mycobacteria, yeast,
Chlamydia,
protazon, helminth or rickettsia, or a virus such as, for example, HIV,
influenza hepatitis
(A,B,C), respiratory syncitial virus (RSV), gastrointestinal viral infections,
encephalitis,
and myocarditis. According to another embodiment of the invention, the immune
system-
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
related condition is the administration of a vaccine, and the up-regulation of
the immune
system results in the increased development of antibodies to an agent targeted
by the
vaccine.
[00272] In especially desirable embodiments of the invention, the
neurotransmitter
system is the endogenous endorphin system, and the type of receptor is delta
opiate
receptors, which are generally negatively linked to undesirable immune system-
related
conditions. The ligand is a delta opiate receptor antagonist, and the
counteradaptation
causes an up-regulation of the immune system. Any of the delta opiate receptor
antagonists described hereinabove may be useful in this embodiment of the
invention. In
some embodiments of the invention, the delta opiate receptor antagonist is not
naltrexone
or naloxone. In some desirable embodiments of the invention, the initial
dosage of the
delta opiate receptor antagonist is greater than 10 mg/administration; greater
than 10.5
mg/administration; greater than 11 mg/administration; or even greater than 15
mg/administration. The delta receptor antagonist is desirably a delta receptor
selective
antagonist; it desirably has substantially less activity with respect to mu
receptors. One
example of a suitable delta receptor antagonist has the structure:
HO
N
OH
HN
[00273] As described above with respect to mood, there may be a decrease in
immune system function during the first time periods associated with each
administration
of the ligand. Further, if a method analogous to that described with reference
to FIG. 6 is
performed, then there may be a decrease in immune system function during the
initial
period of continuous dosing. Accordingly, it may be desirable to administer
one or more
additional medications during these periods. For example, it may be desirable
to
administer an autoimmune medication in combination with the ligand during the
first time
76
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
period and/or during a period of continuous ligand dosing. Examples of
suitable
autoimmune therapy include medications such as corticosteroids, chlorambucil,
cyclosporine, cyclophosphamide, methotrexatate, azathioprine, TNFa
antagonists, and
therapies such as systemic enzyme therapy, gene therapy and irradiation
therapy. Of
course, as the skilled artisan will realize, other autoimmune medications may
be used in the
methods of the present invention, including those developed in the future. In
certain
embodiments of the invention, autoimmune therapy is not administered during
the second
time period.
[00274] Sirnilarly, it may be desirable to administer an antiviral agent in
combination with the ligand during the first time period and/or during a
period of
continuous ligand dosing. Examples of suitable antiviral agents include
interferon,
ribavirin, protease inhibitors, amantadine, rimantadine, pleconaril,
antibodies (monoclonal,
anti-VAP, receptor anti-idiotypic, extraneous receptor and synthetic receptor
mimics),
acyclovir, zidovudine (AZT), lamivudine, RNAase H inhibitors, integrase
inhibitors,
attachment blockers of transcription factors to viral DNA, so-called
`antisense' molecules,
synthetic ribozymes, zanamivir, and osletamivir. Of course, as the skilled
artisan will
realize, other antiviral medications may be used in the methods of the present
invention,
including those developed in the future. In certain embodiments of the
invention, the
antiviral agent is not administered during the second time period.
[00275] Similarly, it may be desirable to administer an antimicrobial agent,
an
antifungal agent, and/or an antineoplastic agent in combination with the
ligand during the
first time period and/or during a period of continuous ligand dosing. In
certain
embodiments of the invention, the antimicrobial agent, the antifungal agent,
and/or the
antineoplastic agent is not administered during the second time period.
[00276] It may be desirable to administer an anti-cancer agent in combination
with
the ligand during the first time period and/or during a period of continuous
ligand dosing.
Suitable anti-cancer agents include, for example, adriamycin, busulfan,
carboplatin,
chlorambucil, cisplatin, cyclophosphamide, ifosfamide, mechlorethamine,
melphalan,
procarbazine, temozolamide, daunorubicin, doxorubicin, idarubicin, bleomycin,
mitomycin, mitoxantrone, plicamycin, cytarabine fluorouracil, hydroxyurea,
methotrexate,
asparaginase, pegaspargase, irinotecan, topotecan, bicalutamide, estramustine,
flutamide,
leuprolide, megestrol, nilutamide, testosterone, triptorelin, anastrazole,
letrozole,
77
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
aldesleukin, alemtuzumab, gemtuzumab, toremifene, trastuzumab, etoposide,
docetaxel,
paclitaxel, vinblastine, vincristine, vinorelbine, altretamine, Erlotinib,
gleevec, curcumin,
tamoxifen, bortezomib, gefitinib, imatinib, cancer cell growth inhibitors
derived from 3,4-
methylenedioxy-5,4'-dimethoxy-3'-amino-Z-stilbene, hydroxyphenstatin and its
sodium
diphosphate prodrug, histone deacetylase inhibitors, suberoylanilide
hydroxamic acid,
trichostatin A, sodium butyrate, metformin, five-lipoxygenase (5-LO)
antagonists,
antisense oligonucleotides targeting the Rla regulatory subunit of protein
kinase A type I,
Vitamin E and its analogs, vitamin E succinate ('VES), and gene therapy. Of
course, as the
skilled artisan will realize, other anti-cancer agents may be used in the
methods of the
present invention, including those developed in the future. In certain
embodiments of the
invention, the antiviral agent is not administered during the second time
period.
[00277] Cancer is one undesirable immune-related condition that may be treated
and/or addressed using the methods described herein. In one desirable
embodiment of the
invention, up-regulation of the immune system is achieved by up-regulating the
endogenous endorphin system using repeated administration of delta opiate
receptor
antagonists as described hereinabove in order to treat or address cancer. Both
cancer cells
and the immune cells (i.e., killer cells) have opiate receptors. When the
immune system
undergoes an up regulation, the killer cells are given an enhanced ability to
`attack' cancer
cells. A further benefit is that the up-regulated cancer cells are made more
susceptible to
cell death. Desirably, the methods described with reference to FIG. 6 are
used, in which a
continuous dose of ligand is first given to induce up-regulation of the immune
system in a
relatively quick manner. The time for this continuous dose could range, for
example, from
one day to several weeks or months depending on the severity of the cancer.
[00278] In addition to merely blocking the enhanced cancer cell proliferation
by the
anti-cancer agents there is an added advantage to the simultaneous use of an
opiate
antagonist with an anti-cancer agent. Because the cancer cells are induced to
grow more
rapidly they are made more susceptible to the effects of anti-cancer agents.
Anti-cancer
agents are thus able to have an enhanced toxic effect on cancer cells during
this period of
time that the cancer cells are rapidly proliferating. The anti-cancer agents
are in this way
made to be more efficacious in inducing cancer cell death.
[00279] The methods described in the present invention may also be used to
treat
and/or address immune disorders and infectious diseases. In one desirable
embodiment of
78
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
the invention, up-regulation of the immune system is achieved by up-regulating
the
endogenous endorphin system using repeated administration of delta opiate
receptor
antagonists as described hereinabove in order to treat or address cancer. In a
manner
similar to initiating cancer therapy, one may opt to begin treatment with a
temporary period
of continuous receptor blockade, as described above with reference to FIG. 6.
[00280] The counteradaptative response to, for example, opiate antagonism is
the up
regulation of the immune system. An up regulated immune system results in an
enhanced
immune response by such immune cells as killer cells as well as other immune
cells. Such
an up regulated immune system can be utilized to treat conditions that have an
abnormal
immune system, These immune disorders can be selected from, but not limited
to,
autoimmune disorders, congenital immune deficiencies, immune deficiencies due
to
immunosuppressant therapy (ie., for cancer, transplantation), or acquired
immune
deficiencies (ie., AIDS). An up regulated immune system can be of further
benefit in that
it is intended to enhance the body's ability to fight off infections, which
include bacterial
and viral infections, as well as those from other infectious microbes.
[00281] Autoimmune disorders are those that have an abnormally functioning
immune system wherein an inunune response is generated against the body's own
tissues.
Because autoimmune disorders are the result of the immune system turning up
its activity
against normal cells and cellular components, it would appear that, if the
immune system
were enhanced, then it should worsen such disorders, due to the enhanced
activity against
one's own tissues. On the contrary, autoimmune system disorders have been
shown to
respond favorably to an enhanced immune system.
[00282] One embodiment of the present invention relates to using relatively
high
doses (ie., an equivalency of greater than 10 mg naloxone or naltrexone, which
further
includes numerous analogs) of delta opiate antagonists for an even relatively
strong up-
regulation of the endogenous endorphin system, hence a relatively strong up-
regulation of
the immune system.
[00283] For many infections there is a secondary added benefit achieved when
practicing methods analogous to those described with reference to FIG. 6, in
which there is
an initial period of continuous receptor blockade. For example, with a viral
infection,
during this period of receptor blockade there would be an enhanced
proliferation of the
viral particles, due to the suppression of the immune system. One could take
advantage of
79
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
this by administering agents that kill or inhibit the virus during
replication. Because the
viral particles are proliferating at a more rapid pace they would become more
susceptible to
agents that inhibit their growth and lead to their death. In this way the
antiviral agent is
made more potent because it attacks the virus during replication when it is
vulnerable. It is
of further benefit in that, following the period of continuous receptor
blockade, there is an
up regulated immune system, wherein the immune cells are more potent in
destroying any
remaining viral particles. Such concomitant antiviral agents may be selected
from the
group interferon, ribavirin, any one of a number of protease inhibitors,
amantadine,
rimantadine, pleconaril, antibodies (monoclonal, anti-VAP, receptor anti-
idiotypic,
extraneous receptor and synthetic receptor mimics), acyclovir, zidovudine
(AZT),
lamivudine, RNAase H inhibitors, integrase inhibitors, attachment blockers of
transcription
factors to viral DNA, `antisense' molecules, synthetic ribozymes, zanamivir
(Relenza ),
and osletamivir (Tamiflu ). As the skilled artisan will appreciate, any
suitable antiviral
medication may be used.
[00284] The methods of the present invention may be used in a prophylactic
manner,
i.e., to lessen the likelihood of becoming infected with any potential
infectious microbe or
virus. The methods of the present invention may be performed, for example,
before an
operation to lessen the risk of infection during and after the operation. The
methods of the
present invention may be used as a prophylactic measure against virtually any
infectious
agent, such as HIV, hepatitis, influenza, RSV, tuberculosis, protozoa,
rickettsia, malaria
and staphylococcus.
OTHER CONDITIONS
[00285] According to another aspect of the present invention, the methods
described
hereinabove are used to address or treat cardiovascular or lipid or
cholesterol metabolism-
related conditions, such as cardiovascular disorders (e.g., cardiac,
peripheral vascular and
stroke). The methods of the present invention are also useful in treating or
addressing
diabetes (e.g., type I and type II).
[00286] Disorders of lipid or cholesterol metabolism generally are
predisposing to
CV and diabetic disorders. Lipid or cholesterol metabolism-related disorder
that may be
addressed or treated using the methods of the present invention include
hypertriglyceridemia, hypercholesterolemia, (including generalized elevation
of cholesterol
and/ or elevation of low-density-lipoprotein cholesterol [LDL], or abnormally
low levels of
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
high-density-lipoprotein [HDL] cholesterol). Disorders of lipid metabolism
further include
the lipodystrophies that are due to HIV (AIDS virus) infections.
[00287] As described above, the AVP neurotransmitter system is involved in
stress,
the ACTH/cortisol pathway and mood disorders such as depression and anxiety. A
different and very specific type of stress is called `nutrient stress'.
Nutrient stress is a
stress situation that occurs with fasting, starvation, or insulin-induced
hypoglycemia.
Nutrient stress results in elevated glucocorticoid levels (cortisol). However,
unlike classic
stress, CRF release does not play a major role in nutrient stress cortisol
release. Instead,
AVP is the primary modulator of cortisol release in response to nutrient
stress.
[00288] Nutrient stress is critical when one discusses factors that are
related to
extending life. It was discovered 70 years ago that caloric restriction (which
induces
nutrient stress) can extend an organism's life by about 30%. This phenomenon
has since
been demonstrated to also occur in numerous mammals including the rat, mouse,
dog and
possibly the primate. In fact, caloric restriction is the only method that has
been proven to
be capable of increasing an organism's lifespan.
[00289] Caloric restriction is thought to work by activating what is called
the SIR 2
gene in yeast, which is known as SIRT1 in mammals. The S1RTI gene encodes an
enzyme
Sirti, which targets proteins that control such critical processes as
apoptosis (cell death),
cell defenses and metabolism. Sirtl is thus thought to be the master
controller of a
regulatory system for aging that is activated by stress.
[00290] For example, Sirtl is a central metabolic regulator in the liver,
muscle and
fat cells. This indicates that Sirti is involved in fat storage, and in this
way it is linked to
aging and metabolic diseases such as type 2 diabetes. Another critical process
that is
modified by Sirtl is inflammation. Caloric restriction is known to suppress
excessive
inflammation, which is associated with aging processes such as heart disease
and
neurodegeneration. Sirtl further regulates production of IGF-1 (insulin-like
growth factor).
IGF-1 is known to dictate life span in various organisms, - worms, flies,
mice, and possibly
humans.
[002911 Compounds that modulate the activity of Sir2 and its human cousins are
collectively referred to as `Sirtuins'. Sirtuin-activating compounds may be
abbreviated
`STAC'. One such STAC is reservatrol. It is commonly found in red wine and in
a variety
81
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
of plants when they are stressed. In fact, some of the beneficial effects on
health from red
wine are thought to be due to reservatrol, and or other STACs. There are
numerous
additional (at least 18) compounds which are produced by plants in response to
stress that
modulate sirtuins.
[00292] One aspect of the invention relates to methods in which the
physiologic
control mechanisms that result from caloric restriction are mimicked in order
to cause an
activation of the Sirtl pathway. Any of the methods and of the present
invention result in
intermittent stress being put on a patient; accordingly, any of the methods of
the present
invention will be useful in activating the Sirtl pathway, and therefore to
treat or address
undesirable conditions linked to the Sirtl pathway, such as conditions related
to aging, fat
metabolism, inflammation and the IGF-1 system. Such conditions include, for
example,
cancer, arthritis, asthma, heart disease and neurodegeneration. The methods of
the present
invention may also be used as a prophylactic measure against physiological
changes caused
by aging. Any of the neurotransmitter systems described above may be used by
the skilled
artisan to activate the Sirtl pathway.
[00293] Caloric restriction is one manner of inducing what has been termed a
`hormetic' effect, or hormesis. In 1904, Starling coined the word "hormone" to
designate
any substance that is produced in small amounts, and is then carried in blood
to influence
some other organ. It is from the Greek "Hormo," meaning, "To excite." Southam
and
Erlich found that high concentrations of oak bark extract inhibited fungal
growth, but in
low dose it stimulated fungal growth. (Phytopathology 33:517, 1943). They
modified
Starling's word to "Hormesis" which describes the notion that small doses of a
toxin can be
helpful. Horniesis is further generalized as a term that refers to the long
term benefits of
mild, repeated stress or stimulation.
[00294] One characteristic of hormesis is that it can be activated following a
certain
stimulus. Mild stress such as increased external temperature, mild radiation
exposure, or
hypergravity, as well as nutritional stress (i.e. Caloric Restriction, [Frame,
L.T., et al.,
"Caloric Restriction as a Mechanism Mediating Resistance to Environmental
Disease",
Environ Health Perspect, 1998, 106 (Suppl 1): 303-324], all have been shown to
improve a
range of parameters associated with aging. Because caloric restriction is not
easily
attainable there has been a drive to develop compounds which mimic the effects
of caloric
restriction. Such compounds are referred to as `caloric restriction mimetics'
(Weindruch,
. 82'
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
R., et al., "Caloric Restriction Mimetics - Metabolic Interventions", Journals
of
Gerontology Series A: Biological Sciences and Medical Sciences, 2001, 56: 20-
33.).
[00295] It is thus not only caloric restriction that induces physiologic
parameters that
improve age related conditions. Any low degree of intermittent stress can also
induce
physiologic parameters that act as defense mechanisms. In this respect, any
mild
intermittent stress will be beneficial for an organism as it induces
physiological parameters
that give it an improved host defense mechanism.
[00296] According to one aspect of the invention, intermittent dosing of
neurotransmitter receptor ligands (as described herein above) is used to
induce a mild
intermittent stress, which in turn activates defense mechanisms that protect
the organism
for times of stress. Any neurotransmitter system linked to dysphoria may be
used to mimic
caloric restriction using the methods described hereinabove. For example, all
of the
neurotransmitter systems described hereinabove are linked to the stressful
condition of
dysphoria. Accordingly, all of the methods, neurotransmitter systems and
ligands
described hereinabove may be used to induce a minor transient stress, and
therefore can be
used to induce hormetic effects and mimic the effects of caloric restriction.
In certain
embodiments of the invention, these defense mechanisms mechanisms that protect
the
organism for times of stress in order to improve conditions of aging, fat
metabolism,
inflammation and the IGF-I system such as cancer, arthritis, asthma, heart
disease and
neurodegeneration.
[00297] Athletic performance is associated with various neurotransmitter
systems,
such as the endogenous endorphin systems. The body produces endorphins in
response to
exercise. The level of intensity and the level of athletic training is
directly associated with
the endorphin response. (see Mougin, et al, Eur J App Physiol, 1988; Doiron,
et al, J Str
Cond Res, 1999; Sforzo, Sport Med, 1989: and Golbfarb, et al., Sport Med,
1997.)
Because highly trained athletes and high levels of intensity during exercise
are directly
related to endorphin release, it would be of benefit for improving athletic
perforrnance with
an up regulated endorphin system. Accordingly, one aspect of the present
invention relates
to the use of the methods, neurotransmitter systems and ligands described
hereinabove for
improving athletic performance. In addition, just as a temporary period of
continous
receptor blockade may be beneficial in cancer therapy, treatment infectious
diseases and
autoimmune therapy as described above, the skilled artsian may use a temporary
period of
83
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
continuous receptor blockade, for example as described with reference to FIG.
6, during
athletic training. According to one embodiment of the present invention, the
neurotransmitter system is the endogenous endorphin system, the ligand is a mu
and/or
delta opiate receptor antagonist, and the counteradaptation is an up-
regulation of the
endogenous endorphin system.
[00298] Cognition (e.g., learning and memory) is also directly associated with
neurotransmitter systems such as the endogenous endorphin system. (Riley, et
al.,
Neurosci Biobehav Rev, 1980; Getsova, et al., Neurosci Behav Physiol, Biomed &
Life
Sci & Russian Library of Sci, 1986.) The acute administration of a delta
opiate receptor
antagonist (e.g., naltrexone) inhibits learning and memory. (Chaves, et al.,
Neuropsychologia, 1988). The link between neurotransmitter systems and
cognition is
further indicated by the fact that levels of glucocorticoids in the
circulation are related to
cognitive function; persistently high levels of cortisol are associated with
impaired
memory. (Li, et al., Neurobio Aging, 2005). On the other hand, transient
elevation of
glucocorticoids improves learning and memory tasks. (Patel, et al., Neurol
Aging, 2002).
Accordingly, one aspect of the present invention relates to the use of the
methods,
neurotransmitter systems and ligands described hereinabove to improve
cognition. For
example, these methods may be used to cause only a transient elevation of
glucocorticoids.
Use of any of the methods, neurotransmitter systems, and ligands described
hereinabove
will cause minor, intermittent stress, which in turn causes transient
temporary elevations of
glucocorticoids. Accordingly, any of the methods, neurotransmitter systems and
ligands
described hereinabove can be used to improve cognition. In another example, to
improve
cognition the skilled artisan can effect an up-regulation of the endogenous
system using a
mu and/or delta opiate receptor antagonist as described hereinabove. In
addition, just as a
temporary period of continous receptor blockade may be beneficial in cancer
therapy,
treatment of infectious diseases and autoimmune therapy as described above,
the skilled
artsian may use a temporary period of continuous receptor blockade, for
example as
described with reference to FIG. 6, in order to create a faster improvement of
cognitive
function.
[00299] It will be apparent to those skilled in the art that various
modifications and
variations can be made to the present invention without departing from the
spirit and scope
of the invention. Thus, it is intended that the present invention cover the
modifications and
84
CA 02643802 2008-08-26
WO 2007/100775 PCT/US2007/004959
variations of this invention provided they come within the scope of the
appended claims
and their equivalents. All references cited herein are hereby incorporated by
reference in
their entirety.