U.S. patent application number 14/405950 was filed with the patent office on 2016-08-25 for synergistic therapies of cannabidiol with hypothermia for neuroprotection.
The applicant listed for this patent is GW Pharma Limited. Invention is credited to Geoffrey Guy, Jose Martinez-Orgado.
Application Number | 20160243054 14/405950 |
Document ID | / |
Family ID | 46605623 |
Filed Date | 2016-08-25 |
United States Patent
Application |
20160243054 |
Kind Code |
A2 |
Martinez-Orgado; Jose ; et
al. |
August 25, 2016 |
SYNERGISTIC THERAPIES OF CANNABIDIOL WITH HYPOTHERMIA FOR
NEUROPROTECTION
Abstract
The present invention relates to the combination of the
phytocannabinoid cannabidiol with therapeutic hypothermia for use
in the treatment of neuroprotection or astroprotection.
Inventors: |
Martinez-Orgado; Jose;
(Majadahonda, Madrid, ES) ; Guy; Geoffrey;
(Salisbury, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GW Pharma Limited |
Salisbury |
|
GB |
|
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20150148872 A1 |
|
|
US 20150328171 A2 |
November 19, 2015 |
|
|
Family ID: |
46605623 |
Appl. No.: |
14/405950 |
Filed: |
June 10, 2013 |
PCT Filed: |
June 10, 2013 |
PCT NO: |
PCT/GB2013/051519 PCKC 00 |
371 Date: |
December 5, 2014 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 7/00 20130101; A61K
31/05 20130101; A61K 31/05 20130101; A61P 25/00 20180101; A61F 7/02
20130101; A61K 36/185 20130101; A61F 2007/0056 20130101; A61P 9/10
20180101; A61P 43/00 20180101; A61K 2300/00 20130101 |
International
Class: |
A61K 31/05 20060101
A61K031/05; A61F 7/00 20060101 A61F007/00; A61K 36/185 20060101
A61K036/185 |
Claims
1. A method for treatment of newborn hypoxic-ischemic
encephalopathy (NHIE) comprising administering to a newborn
suffering from NHIE a combination of the phytocannabinoid
cannabidiol (CBD) with therapeutic hypothermia.
2. The method as claimed in claim 1, wherein the CBD is in the form
of a plant extract.
3. The method as claimed in claim 1, wherein the CBD is in a pure
or isolated form.
Description
[0001] The present invention relates to the use of the
phytocannabinoid cannabidiol (CBD) in combination with other
therapies that are useful in neuroprotection. Preferably the other
therapy is hypothermia. In a further embodiment the combination
treatment of hypothermia and CBD may additionally include further
treatments that are useful in neuroprotection. Such therapies
include anti-epileptic drugs; xenon; N-acetylcysteine;
erthyropoietin, and melatonin. Preferably the neuroprotective
therapies are used in the treatment of hypoxic-ischemic
encephalopathy (HIE), more preferably the HIE is newborn
hypoxic-ischemic encephalopathy (NHIE), stroke or cardiac
arrest.
BACKGROUND TO THE INVENTION
[0002] Perinatal asphyxia resulting in newborn hypoxic-ischemic
encephalopathy (NHIE) occurs in between 2 to 9/1000 live term
newborns. A vastly higher number of preterm babies (60/1000 live
preterm babies) also suffer from this condition. In addition to
inflicting direct brain damage, leading to acute brain dysfunction,
such an insult can also interfere with brain development,
determining long-term morbidity.
[0003] Worldwide approximately 2 million babies die or remain with
long-lasting disability because of NHIE each year.
[0004] Despite the continuous progress in Neonatology and
Perinatology recently, the aforementioned numbers have not
substantially changed. Thus, NHIE remains as the main cause of
acquired neonatal neurological impairment of babies worldwide.
[0005] Management of NHIE is determined by its complex
pathophysiology. After the early energetic fall during
hypoxia-ischemia, failure of neuronal ionic pumps lead to a toxic
increase of intracellular calcium, activating degrading enzymes.
There is also an increase in extracellular excitotoxic substances
such as glutamate, which further increases calcium influx.
[0006] During reperfusion, re-oxygenation and inflammatory
responses start a second wave of damage, which lead to a secondary
energetic failure and to DNA damage, activating apoptosis.
[0007] Substances within the body such as heat shock proteins,
antiapoptotic proteins, neural growth factors and endocannabinoids
are able to act as natural neuroprotective and neuro-regenerative
substances. However in the majority of cases lack of treatment
results in severe brain damage or death.
[0008] The immature brain is particularly susceptible to
hypoxic-ischemic damage because of a higher sensitivity to
glutamate, cytokines and oxidative stress, and the preponderance of
pro-apoptotic mechanisms.
[0009] Hypoxic-ischemic (HI) damage may affect the fetus at various
stages of fetal development, or it can affect the newborn during
labour and delivery and in the postnatal period.
[0010] Problems during pregnancy may include preeclampsia, maternal
diabetes with vascular disease, congenital fetal infections,
drug/alcohol abuse, severe fetal anemia, cardiac disease, lung
malformations, or problems with blood flow to the placenta.
[0011] Problems during labour and delivery can include umbilical
cord occlusion, torsion or prolapse, rupture of the placenta or
uterus, excessive bleeding from the placenta, abnormal fetal
position such as the breech position, prolonged late stages of
labour, or very low blood pressure in the mother.
[0012] Problems after delivery can include severe prematurity,
severe lung or heart disease, serious infections, trauma to the
brain or skull, congenital malformations of the brain, or very low
blood pressure in the baby.
[0013] There is a "temporary therapeutic window" between the HI
insult and the irreversible secondary energetic failure, which
determines the possibility of a therapeutic strategy leading to the
reduction of HI brain damage. Such a strategy has to act on several
factors, including excitotoxicity, oxidative stress and
inflammation.
[0014] Therapeutic hypothermia has been demonstrated to be a useful
treatment of NHIE and has become the only therapy with a proven
neuroprotective effect in human newborns. Unfortunately, these
benefits are partial and only successful in mild cases.
[0015] Recent clinical trials in newborns have demonstrated that
induced moderate hypothermia reduces the combined outcome of
mortality and long-term neurodevelopmental disability at 12-24
months of age. Aside from hypothermia, no established therapies
exist.
[0016] Hypothermia does not completely protect an injured brain;
newborns with the most severe forms of HI injury are often not
successfully treated.
[0017] The addition of other therapies added during or after
hypothermia that can improve neuroprotection, by extending the
therapeutic window or providing long-lasting additive or
synergistic protection, are needed (Cilio and Ferriero, 2010).
However it is important to consider that drugs administered during
the neonatal period may be toxic to the immature brain. Excretion
of many drugs and their metabolites can be modified by hypothermia,
and thus failure of liver and kidney clearance due to HI injury
could exacerbate any toxicity.
[0018] Anti-epileptic drugs (AED) have been used in combination
with hypothermia mainly because seizures are commonly associated
with HIE. The AED Topiramate has shown some synergy with
hypothermia in animal models if used immediately after the HI
event, however the dose used was well above that used for treatment
of epilepsy in children.
[0019] Indeed Cilio and Ferriero suggest agents such as xenon;
N-acetylcysteine; erthyropoietin, melatonin and cannabinoids might
augment the protection from hypothermia.
[0020] The applicant proposed that since cannabinoids reduce
calcium influx and glutamate release, are antioxidant and
anti-inflammatory substances, modulate MAP kinase pathways, induce
hypothermia and promote neuro-regeneration they might be used in
the treatment of NHIE. Many of these effects, however, are due to
CB1 receptor activation. In immature brains, over activation of CB1
receptors is known to increase apoptosis. Thus, CB1 agonists are
not suitable for neuroprotection in NHIE.
[0021] The non-psychoactive cannabinoid cannabidiol (CBD) is of
great interest because its effects are CB1-independent. Indeed CBD
has been shown to reduce histological and biochemical brain damage
in in vivo and in vitro models of NHIE (Alvarez et al., 2008). This
cannabinoid has also been shown to provide beneficial effects for
at least 3 days post the HI event (Lafeunte et al., 2011).
[0022] Additionally the United Kingdom patent GB 2,434,312
describes the neuroprotective properties of a CBD plant
extract.
[0023] Currently the lack of useful treatments to augment
therapeutic hypothermia mean a considerable financial and lifelong
personal burden on society and the affected families of newborns
suffering from NHIE. Therefore there is an urgent need to improve
the outcome for these infants.
[0024] Surprisingly, the combination of therapeutic hypothermia
with the cannabinoid CBD has been shown to be synergistic in
neuroprotection following HI injury in an animal model of NHIE, and
as such offers a beneficial treatment option for NHIE.
BRIEF SUMMARY OF THE DISCLOSURE
[0025] In accordance with a first aspect of the present invention
there is provided a combination of the phytocannabinoid cannabidiol
(CBD) with therapeutic hypothermia for use in the treatment of
hypoxic ischemia.
[0026] Preferably the CBD is in the form of a plant extract.
Alternatively the CBD is in a pure or isolated form.
[0027] Preferably the hypoxic ischemia to be treated is newborn
hypoxic-ischemic encephalopathy (NHIE).
[0028] Alternatively the hypoxic ischemia to be treated is a stroke
or a cardiac arrest.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Embodiments of the invention are further described
hereinafter with reference to the accompanying drawings, in
which:
[0030] FIG. 1 shows the histology of piglet brains treated after HI
injury;
[0031] FIG. 2 shows a comparison of brain lesions in rats after HI
injury; and
[0032] FIG. 3 shows the neurobehavioural performance of rats after
HI injury.
DETAILED DESCRIPTION
[0033] Example 1 below demonstrates the prior art and details the
neuroprotective properties of CBD in two different models. It is
demonstrated that the CBD enables repair of brain tissue after an
HI injury.
[0034] Example 2 demonstrates the synergistic neuroprotective
effect of CBD with therapeutic hypothermia.
Example 1
Neuroprotective Properties of Cannabidiol (CBD) Following
Hypdxic-Ischemica (HI)
Materials and Methods
[0035] A piglet model of HI was used as described in (Alvarez et
al. 2008). Briefly, an HI insult is induced in anesthetized 1-3
day-old piglets by occluding both carotid arteries and decreasing
inspired oxygen from 21 to 10% for 30 min.
[0036] Thirty minutes after the recovery of HI the test compound
was administered via the i.v. route. The test compounds were:
Vehicle;
CBD (1 mg/kg); CBD (1 mg/kg) plus AM630 which is a CB2 antagonist
(1 mg/kg); CBD (1 mg/kg) plus WAY100635 which is a 5HT1A antagonist
(0.1 mg/kg); or CBD (1 mg/kg) plus Caffeine which is a non-specific
adenosine receptor antagonist (10 mg/kg).
[0037] Hemodynamic parameters (cardiac output, blood pressure,
heart rate and extravascular lung water content), temperature,
respiratory parameters (lung compliance, airway resistance,
oxygenation index) were recorded for 6 hours from the end of
HI.
[0038] Blood samples were obtained hourly and urine was collected.
Brain activity was recorded by amplitude-integrated EEG.
[0039] At the end of the experiment, piglets are euthanized and the
brain removed; one hemisphere was immediately frozen and stored at
-80.degree. C. whereas the other one was preserved in 4%
paraformaldehide. A sample of frozen brain was obtained to perform
a proton magnetic resonance spectroscopy (H+-MRS). Similarly
managed piglets but without HI served as controls.
[0040] Blood samples from CBD-treated piglets were used to
determine serum CBD concentration.
[0041] A rat model of HI was used as described by (Fernandez-Lopez
et al., 2007). Briefly, an HI insult is induced in 7-10 day-old
Wistar rats by electro-coagulating the left carotid artery under
anaesthesia following by the exposure to 10% oxygen for 120
min.
[0042] After the end of HI, pups were treated with 0.1 mL s.c. of
vehicle or CBD (1 mg/kg) in a single dose.
[0043] Sham operated pups without hypoxia served as controls, and
were treated with vehicle or CBD as indicated. The pups were then
returned to their dams.
[0044] At day 35 rats underwent neurobehavioral tests: rotarod (to
test coordination), cylinder (to test unilateral deficits) and
novel object preference (to test memory impairments).
[0045] Rats were then euthanized and the brain removed and stored
in 4% paraforlmadehide. Magnetic resonance imaging was performed on
the brains to evaluate the damaged area. In some rats, MRI was
performed 7 days after HI.
Results
[0046] Piglet Model
[0047] FIG. 1a) and b) shows the brain tissue obtained 6 h after
the end of hypoxia-ischemia (HI). FIG. 1a) compares Nissl staining
of brain slices from sham piglets to those exposed to HI and
treated with vehicle or CBD 1 mg/kg i.v., alone or with the CB2
antagonist AM630 (AM), the 5HT1A antagonist WAY100630 (WAY) or the
adenosine antagonist caffeine (CAF).
[0048] As can be seen CBD reduces the percentage of necrotic tissue
in both the cortex and the hippocampus. The CBD-induced reduction
of neuronal death is blunted by either AM or WAY, but not by
caffeine.
[0049] FIG. 1b) shows the concentration of interleukin 1 in brain
tissue determined by microarrays. Again CBD reduces the production
of IL-1, which is blunted by AM but not by WAY or caffeine.
Rat Model
[0050] FIG. 2 demonstrate the Magnetic Resonance imaging (MRI) of
the rat brains, these revealed that the volume of lesion was
similar in HI+VEH and HI+CBD 7 days after HI, suggesting that the
severity of brain damage was similarly strong in both groups.
[0051] One month later (P37), the brain volume remained similar in
HI+VEH but was significantly reduced by CBD.
[0052] FIG. 3 demonstrates the protective effect of CBD included
not only the volume of lesion but also the neurobehavioral
performance of the rat. CBD administration led to the normalization
of motor (cylinder rear test), coordination (RotaRod) and memory
(novel object recognition) tests, whereas the untreated rats
performed poorly in the neurobehavioral tests.
Conclusion
[0053] The piglet model showed that the CBD was able to reduce the
amount of necrotic areas in the brain caused by HI.
[0054] The rat model showed that CBD is neuroprotective and in
addition to this effect a reduction of brain damage was observed
after a month. The cannabinoid CBD is stimulating neuro-repair.
Example 2
Synergistic Administration of Cannabidiol (CBD) with Therapeutic
Hypothermia Following Hypdxic-Ischemica (HI)
Materials and Methods
[0055] Sedated and ventilated piglets (1-2 day-old) underwent HI
brain damage (hypoxia-FiO2 10%+bilateral carotid artery compression
for 30 min).
[0056] Normothermic (NT) piglets were maintained at 37-38.degree.
C. using a warmed air blanket.
[0057] Hypothermic (HT) piglets were cooled by a cool water
mattress to 33-34.degree. C.
[0058] Thirty min after HI piglets received via the i.v. route
either vehicle (VEH) or CBD (1 mg/kg).
[0059] HI brains were obtained for histological studies quantifying
the number of neurons (Nissl), astrocytes (GFAP) and microglial
cells (mGC) (IBA-1) in parietal cortex 6 hours after HI injury.
[0060] By dividing the area percentage of GFAP- or
IBA-1-immunoreactive processes and cell bodies (ImageJ) by the
number of cells, a mean size of astrocytes or mGC was obtained.
[0061] Similarly studied animals without HI insult served as
controls (Sham, SHM).
Results
[0062] Neuronal protection was found to be best in the CBD plus
hypothermia treated animals, (p<0.05).
[0063] CBD prevented the HI-induced reduction in the number of
astrocytes, particularly in the hypothermia treated animals.
[0064] CBD also enhanced astrocyte activity (increased processes
equals an increased mean size), particularly in CBD plus
hypothermia.
[0065] Hypothermic treatment reduced the number of microglial
cells, with no differences between the vehicle treated animals and
those treated with CBD.
[0066] Table 2.1 demonstrates the mean size of the microglial cells
after HI injury
TABLE-US-00001 Mean size (pixels) Normothermic Control 102 HI
injury + Vehicle 134 HI injury + CBD 127 Hypothermic Control 164 HI
injury + Vehicle 219 HI injury + CBD 176
[0067] As can be seen from the table above the microglial cells
were activated after HI, increasing their size, this is
demonstrated in the normothermic plus vehicle treated animals where
the size of pixels increased from 102 to 134 pixels a rise of 32
pixels. Treatment with CBD and hypothermia produced the smallest
increase 164 to 176 pixels a rise of just 12 pixels, compared to
CBD alone (102 to 127 pixels, a rise of 25 pixels) and hypothermia
alone (164 to 219 pixels, a rise of 55 pixels)
[0068] Table 2.2 below details the percentage of necrotic neurons
found in the cortex of the test animals.
TABLE-US-00002 TABLE 2.2 Percentage of necrotic neurons in the
cortex of test animals MEAN (%) Normothermic Control 5.64 HI injury
+ Vehicle 26.46 HI injury + CBD 8.41 Hypothermic Control 1.67 HI
injury + Vehicle 13.19 HI injury + CBD 4.51
[0069] As can be seen treatment with a combination of hypothermia
and CBD produced the lowest percentage of necrotic neurons (4.5%)
compared to hypothermia alone (13.2%) and treatment with CBD alone
(8.4%).
Conclusion
[0070] CBD administration after HI protects neurons and astrocytes
and modulates microglial activation.
[0071] Moreover CBD is slightly more effective than hypothermia,
but when both therapies are used in combination statistically
significant neuroprotective effects occur.
[0072] This synergy provides a useful treatment option in newborns
suffering from NHIE. In addition such treatments could be used
effectively in the treatment of other human patients suffering from
hypoxic ischemic events or diseases such as stroke or cardiac
arrest.
References
[0073] CILIO and FERRIERO, Synergistic neuroprotective therapies
with hypothermia, Semin Fetal Neonatal Med. October 2010; 15(5):
293-298.
* * * * *