Combination therapy for Alzheimer’s Disease, Lithium + Beta-Secretase (BACE) Inhibitor, Memantine + Levetiracetam + BACE Inhibitor, Levetiracetam + BACE Inhibitor

1. James Wallace
Combination therapy for the treatment and prevention
of Alzheimer’s Disease
1 : - U.S. Patent Pending #US 20160213645 A1
2 : - U.S. Patent Pending #US 20140271911 A1
• Levetiracetam + BACE Inhibitor 1
• Memantine + Levetiracetam + BACE Inhibitor 1
• Lithium + BACE Inhibitor 2

2. Words of Caution
This presentation is for educational purposes only. Please work with a
knowledgeable physician before beginning any type of supplement or
medication protocol.

3. I developed the hypothesis that simultaneously
targeting neuronal hyperactivity and the enzymatic
cleavage of Amyloid Precursor Protein (APP), prior to
the onset of symptoms during the long preclinical
phase, will prevent or reduce the severity of
Alzheimer’s disease by specifically targeting region-
specific brain areas that are vulnerable to pathology.

4. Hypothesis
APP CleavageNeuronal
Hyperactivity
Alzheimer’s Dementia
Mediated by Ca2+
signaling
Mediated by β- and γ-
secretase

5. Linking Neuronal Hyperactivity with Calcium Signaling, Amyloid, Mitochondrial
Dysfuntion, ER Stress, and Neurodegeneration
Increased Activity
Is Paired With Calcium
Signaling and Calcium Influx
Metabolic Stress
and ROS 1,2 Calcium Derangements 3,4 Increased
Synaptic Exocytosis 5,6
• Progressive Oxydative Damage
• Mitochondrial Dysfunction
• Diminished Metabolic Capacity
• ER Stress/UPR/Inflam./Misfolding
• Excitotoxic Damage
• ER Stress/UPR/Inflam./Misfolding
• Synaptic Dysfunction
• Interstitial Amyloid
• Amyloid Deposits
• Synaptic Dysfunction
1 – Celsi F. et al., “Mitochondria, calcium and cell death: a deadly triad in neurodegeneration” Biochim. Biophys. Acta., Vol. 1787, 2009, 335-344.
2 - Calì T. et al., “Mitochondrial Ca2+ and neurodegeneration.” Cell Calcium, vol. 52, 2012, 73-85.
3 – Szydlowska K. and Tymianski M., “Calcium, ischemia and excitotoxicity” Cell Calcium, vol. 47, 2010, 122-129.
4 – Zhang H. et al., “Calcium signaling, excitability, and synaptic plasticity defects in a mouse model of Alzheimer's disease” J. Alzheimers Dis., vol. 45, 2015, 561-580.
5 – Cirrito J.R. et al., "Synaptic activity regulates interstitial fluid amyloid-beta levels in vivo.", Neuron, vol. 48, 2005, 913-922.
6 - Bero A.W. et al. “Neuronal activity regulates the regional vulnerability to amyloid-β deposition” Nat. Neurosci., vol 14, 2011, 750-766.

6. In AD:
Post–Alzheimer’s Disease
Milieu
•Synaptic dysfunction
•Autophagy dysfunction
•Increased resting Ca2+ levels
•Reduced metabolic functioning
•Decreased # of mitochondria
•ER stress/Inflammation
•Amyloid/Tau

7. BACE Inhibitors in Late-Stage Testing:
 LY3202626 - Eli Lilly
 E2609 (Elenbecestat) – Eisai / Biogen
 CNP520 – Novartis / Amgen
Clinical Trials
Levetiracetam:
The HOPE4MCI Phase 3 clinical trial to evaluate a low
dose form of levetiracetam for Alzheimer’s disease has
received support from the National Institutes of Health
(NIH) (expected to start in 2018).
Lithium:
The Lithium As a Treatment to Prevent Impairment of
Cognition in Elders (LATTICE) is Phase 4 clinical trial
to evaluate lithium for impeding cognitive decline.

8. Levetiracetam:
 Levetiracetam for Alzheimer's Disease-
Associated Network Hyperexcitability (LEV-AD)
 Clinical Trials ID: NCT02002819
 Phase 2
Lithium:
 Lithium As a Treatment to Prevent Impairment
of Cognition in Elders (LATTICE)
 Clinical Trials ID: NCT03185208
 Phase 4

9. AGB-101
 AGB-101 is a long-acting form of levetiracetam
developed by AgeneBio in partnership with
Johns Hopkins University.
AGB-101 (Hope4MCI)

10. As described in the Amyloid hypothesis, Alzheimer’s disease is preceded
by, and in some unproven manner is initiated by, Amyloid. 1-3 By
disrupting the cleavage of Amyloid Precursor Protein (APP), beta-
secretase inhibitors can potentially reduce the generation of Amyloid and
reduce Amyloid deposits 4,5, and thus, beta-secretase inhibitors, may
potentially impede the downstream effects from Amyloid and the
progression of AD, prior to the onset of symptoms.
Proposed Mechanism of Action
for BACE Inhibition
1 - Hardy J. and Allsop D., “Amyloid deposition as the central event in the aetiology of Alzheimer's disease”, Trends Pharmacol. Sci., vol. 12, 1991, 383-388.
2 - Karran E. et al., "The amyloid cascade hypothesis for Alzheimer’s disease: an appraisal for the development of therapeutics", Nat. Rev. Drug Discov., vol. 10,
2011, 698-712..
3 - Sperling R.A. et al., "Toward defining the preclinical stages of Alzheimer's disease: recommendations from the National Institute on Aging-Alzheimer's
Association workgroups on diagnostic guidelines for Alzheimer's disease”, Alzheimers Dement., vol. 7, 2011, 280-292..
4 - Ghosh A.K. et al., “Beta-Secretase as a therapeutic target for Alzheimer's disease”, Neurotherapeutics, vol. 5, 2008, 399-408.
5 - Vassar R. et al., “Beta-secretase cleavage of Alzheimer's amyloid precursor protein by the transmembrane aspartic protease BACE”, Science, vol. 286, 1999,
735-741.

11. A coding substitution on Amyloid Precursor
Protein (APP) adjacent to the beta-secretase
cleavage site is associated with protection
against Alzheimer’s disease.
The A673T Substitution
Jonsson T. et al., "A mutation in APP protects against Alzheimer’s disease and age-related
cognitive decline", Nature, 2012, vol. 488, 96–99.

12.  Long before the onset of neurodegeneration, brain regions with higher rates of
activity and metabolism in young adults - overlap regions observed to have
significant quantities of amyloid depositi0n in subjects with Alzheimer’s disease
- in the default mode network (DMN). 1,2
 In transgenic Tg2576 mice, higher concentrations of interstitial amyloid and
higher quantities of amyloid deposition have been observed in brain regions
with higher rates of activity. 3
 It has been proposed that neurons with increased activity rates have higher
rates of synaptic vesicle release and higher rates of synaptic amyloid release
resulting in increased concentrations of interstitial amyloid. 4
 In Tg2576 mice, higher concentrations of interstitial amyloid have been shown
to influence amyloid deposition. 3
Does region-specific neuronal hyperactivity influence
and promote region-specific amyloid deposition?
1 - Buckner R.L. et al.,“Molecular, structural, and functional characterization of Alzheimer's disease: evidence for a relationship between
default activity, amyloid, and memory”, J. Neurosci., vol. 25, 2005, 7709-7717.
2 - Buckner R.L. et al., “The brain's default network: anatomy, function, and relevance to disease”, Ann. NY Acad. Sci., vol. 1124, 2008, 1-38.
3 - Bero A.W. et al., "Neuronal activity regulates the regional vulnerability to amyloid-β deposition." Nat. Neurosci., vol. 14, 2011, 750-756.
4 - Cirrito J.R. et al., "Synaptic activity regulates interstitial fluid amyloid-beta levels in vivo.", Neuron, vol. 48, 2005, 913-922.
Roselli F. and Caroni P., "From Intrinsic Firing Properties to Selective Neuronal Vulnerability in Neurodegenerative Diseases" Neuron, vol. 85,
2015, 901-910.
Busche M.A. and Konnerth A., "Neuronal hyperactivity - A key defect in Alzheimer's disease?", Bioessays, 2015, Epub ahead of print.

13. Increased
Neuronal Activity
Increased Interstitial
Amyloid
Amyloid Deposits
Neuronal Hyperactivity (1-4)
1 - Bero A.W. et al., "Neuronal activity regulates the regional vulnerability to amyloid-β deposition“, Nat. Neurosci., vol. 14, 2011, 750-756.
2 - Cirrito J.R. et al., "Synaptic activity regulates interstitial fluid amyloid-beta levels in vivo", Neuron, vol. 48, 2005, 913-922.
3 - Roselli F. and Caroni P., "From Intrinsic Firing Properties to Selective Neuronal Vulnerability in Neurodegenerative Diseases“, Neuron, vol. 85,
2015, 901-910.
4 - Busche M.A. and Konnerth A., "Neuronal hyperactivity - A key defect in Alzheimer's disease?", Bioessays, 2015, Epub ahead of print.
Higher Rates of Synaptic Vesicle and
Synaptic Amyloid Exocytosis

14. The Default Mode Network and Amyloid
Buckner R.L. et al.,“Molecular, structural, and functional characterization of Alzheimer's disease:
evidence for a relationship between default activity, amyloid, and memory”, J. Neurosci., vol. 25,
2005, 7709-7717

15. Linking Neuronal Hyperactivity with Calcium Signaling, Amyloid, Mitochondrial
Dysfuntion, ER Stress, and Neurodegeneration
Increased Activity
Is Paired With Calcium
Signaling and Calcium Influx
Metabolic Stress
and ROS 1,2 Calcium Derangements 3,4 Increased
Synaptic Exocytosis 5,6
• Progressive Oxydative Damage
• Mitochondrial Dysfunction
• Diminished Metabolic Capacity
• ER Stress/UPR/Inflam./Misfolding
• Excitotoxic Damage
• ER Stress/UPR/Inflam./Misfolding
• Synaptic Dysfunction
• Interstitial Amyloid
• Amyloid Deposits
• Synaptic Dysfunction
1 – Celsi F. et al., “Mitochondria, calcium and cell death: a deadly triad in neurodegeneration” Biochim. Biophys. Acta., Vol. 1787, 2009, 335-344.
2 - Calì T. et al., “Mitochondrial Ca2+ and neurodegeneration.” Cell Calcium, vol. 52, 2012, 73-85.
3 – Szydlowska K. and Tymianski M., “Calcium, ischemia and excitotoxicity” Cell Calcium, vol. 47, 2010, 122-129.
4 – Zhang H. et al., “Calcium signaling, excitability, and synaptic plasticity defects in a mouse model of Alzheimer's disease” J. Alzheimers Dis., vol. 45, 2015, 561-580.
5 – Cirrito J.R. et al., "Synaptic activity regulates interstitial fluid amyloid-beta levels in vivo.", Neuron, vol. 48, 2005, 913-922.
6 - Bero A.W. et al. “Neuronal activity regulates the regional vulnerability to amyloid-β deposition” Nat. Neurosci., vol 14, 2011, 750-766.

16. Epilepsy
TBI
Other conditions with a known association
of regional neuronal over-stimulation +
regional amyloid accumulations:

17.  Extracellular/Interstitial Amyloid has been proposed to exert toxicity on cell
membranes and neurotransmitter receptors, contributing to synaptic failure 1 - 3
 Intracellular Amyloid has been proposed to disrupt the intracellular milieu of
neurons, contributing to organelle pathology, including mitochondrial damage,
and ER Stress. 4, 5
Extracellular and Intracellular
Amyloid
1 - Nixon R.A., "Autophagy, amyloidogenesis and Alzheimer disease“, J. Cell Sci., vol. 120, 2007, 4081-91.
2 - Nixon R.A., "Alzheimer neurodegeneration, autophagy, and Abeta secretion: the ins and outs (comment on DOI
10.1002/bies.201400002)", Bioessays, vol. 36, 2014, 547.
3 - Wang Y. et al., "Multiple effects of β-amyloid on single excitatory synaptic connections in the PFC”, Front Cell
Neurosci., vol 7, 2013: 129
4 - Umeda T., "Intraneuronal amyloid β oligomers cause cell death via endoplasmic reticulum stress,
endosomal/lysosomal leakage, and mitochondrial dysfunction in vivo", J. Neurosci. Res., vol. 89, 2011, 1031-1042.
5 - Wirths O., "Intraneuronal Aβ accumulation and neurodegeneration: lessons from transgenic models“, Life Sci., vol.
91, 2012, 1148-1152.

18. Increased Neuronal Activity
Increased Interstitial Amyloid
Neuronal Hyperactivity and Amyloid
Higher Rates of Synaptic Vesicle and Synaptic Amyloid
Exocytosis
Synaptic Dysfunction + Extracellular Amyloid Accumulations
(early symptoms)
Cellular Dysfunction/Intracellular Pathology - Intracellular
Amyloid Accumulations + Tau + Impaired Autophagy
(moderate - late disease stages)

19.  Autophagy mediated extrusion of amyloid (which has been shown to
be less impaired during preclinical stages) might influence and
contribute to extracellular amyloid accumulations – particularly during
early phases of disease. 1 - 2
 Autophagy impairments (which have been shown to become
significant during the later stages of Alzheimer’s disease) might
influence and contribute to intracellular amyloid accumulations –
particularly during later phases of disease. 3
Potential Role of Autophagy in Amyloid
Processing - Extracellular and Intracellular
Amyloid
1 - Nilsson P. et al., "Aβ secretion and plaque formation depend on autophagy", Cell Rep., vol 5, 2013, 61-69.
2 - Nilsson P., Saido T.C., "Dual roles for autophagy: degradation and secretion of Alzheimer's disease Aβ
peptide", Bioessays, vol. 36, 2014, 570-578.
3 - Nixon R.A., "Autophagy, amyloidogenesis and Alzheimer disease" J. Cell Sci., vol. 120, 2007, 4081-91.

20. Recent Evidence and Discussion of
Region-Specific Dysfunction in AD – 2018
 Chhatwal J.P. et al., "Preferential degradation of cognitive
networks differentiates Alzheimer's disease from ageing."
Brain, 2018.
 Gordon B.A. et al., "Spatial patterns of neuroimaging
biomarker change in individuals from families with autosomal
dominant Alzheimer's disease: a longitudinal study." Lancet
Neurol., v. 17, 2018, 241-250.

21. Recent Evidence and Discussion of
Region-Specific Dysfunction in AD – 2018
 Zott B, Busche MA, Sperling RA, Konnerth A. “What Happens
with the Circuit in Alzheimer's Disease in Mice and Humans?”
Annu Rev Neurosci., v. 41, 2018, 277-297.

22. Amyloid Accumulations
(regional)
Dementia
Amyloid -> Dementia
Hypometabolism
(regional)
Atrophy
(regional)
Gordon B.A. et al., "Spatial patterns of neuroimaging biomarker change in individuals from families with autosomal dominant
Alzheimer's disease: a longitudinal study." Lancet Neurol., v. 17, 2018, 241-250.

23.  Two regions in the DMN marked by early amyloid
accumulations upstream of symptom onset are the Precuneus
and the Posterior Cingulate Gyrus.
 The Precuneus and Posterior Cingulate Gyrus, along with the
hippocampus, may have significance in both the pathogenesis
and early identification of AD.
 Metabolism in the Precuneus has been shown to decrease an
average of 18.8 years prior to estimated onset of symptoms in
DIAN subjects. 1
 Atrophy in the Precuneus has been shown to begin an average
of 13 years prior to the estimated onset of symptoms in DIAN
subjects. 1
1-Gordon B.A. et al., "Spatial patterns of neuroimaging biomarker change in individuals from families with autosomal dominant
Alzheimer's disease: a longitudinal study." Lancet Neurol., v. 17, 2018, 241-250.
Precuneus and the
Posterior Cingulate Gyrus

24. Precuneus + the DMN

25. Precuneus + the DMN
1 - Utevsky A.V., Smith D.V., Huettel S.A., "Precuneus is a functional core of the default-mode network." J
Neurosci., vol. 34, 2014, 932-940.
 The Precuneus has been described as the functional core of
the Default Mode Network. 1
 Over-activity of the DMN, and specifically, over-activity in the
Precuneus, may potentially contribute to the early
deterioration of the Precuneus, and DMN degradation more
broadly, observed in subjects who subsequently develop AD.

26. Can levetiracetam influence the Precuneus?
* Press D., "The effect of acute administration of levetiracetam on cerebral perfusion in Alzheimer's disease as
measured by arterial spin labeling MRI.", Alzheimer's and Dementia, vol.9, 2013, p.894.
“The acute administration of i.v. levetiracetam lead to a pattern of
relative decreased perfusion in posterior parietal regions and
relative increased perfusion in anterior temporal lobe regions.
The presence of significant changes in CBF after drug
administration suggests that LEV is modifying neuronal activity.
The relative CBF increase in anterior temporal lobe and decreases
in posterior cingulate/precuneus regions could represent
differential effects directly on hyperexcitability vs. indirect
changes related to reduced inhibitory network activity.” *

27.  Lerdkrai C. et al. “Intracellular Ca2+ stores control in vivo neuronal
hyperactivity in a mouse model of Alzheimer's disease.” Proc Natl Acad Sci
U S A. vol. 115, 2018. E1279-E1288.
Intracellular Ca2+ and Neuronal
Hyperactivity

28.  In neurons, Ca2+ in the cytoplasm mediates both Long-Term Potentiation (LTP)
and Long-Term Depression (LTD). 1
 Resting intraneuronal calcium levels in the cytoplasm ~ 100 nM. 2
 Increased intracellular calcium concentrations have been observed in neurons
from 3xTg-AD mice. 3
 Models of Alzheimer’s disease suggest that increased resting intracellular calcium
levels contributes to the disruption of memory consolidation. 4
Intracellular Calcium
1 - Malenka R.C. and Bear M.F., "LTP and LTD: an embarrassment of riches", Neuron, vol. 44, 2004, 5–21.
2 - Berridge M.J et al., "The versatility and universality of calcium signaling", Nat. Rev. Mol. Cell Biol., vol. 1,
2000, 11–21.
3 - Lopez J.R. et al., “Increased intraneuronal resting [Ca2+] in adult Alzheimer's disease mice”, J.
Neurochem., vol. 105, 2008, 262-271.
4 - Bezprozvanny I. and Hiesinger P.R., “The synaptic maintenance problem: membrane recycling, Ca2+
homeostasis and late onset degeneration”, Mol. Neurodegener., vol. 8, 2013, 23.

29.  Lithium has been shown to antagonize NMDA receptors
-Nonaka et al. EC50 of Li – 1.3 mEq/L, 6–7 days of Li required for maximum effect, 24 h of Li
was ineffective; Hashimoto et al. EC 50 of Li – 0.4 mEq/L, At 1.0 mEq/L 5–6 days required for
maximum effect, 1 h of Li was ineffective. 1,2
 Lithium has been shown to inhibit Inositol Monophosphatase (IMP) and reduce Inositol
Triphosphate (IP3)
-In vitro experiments by Hallcher et al. (1980) and Berridge et al.(1982) have shown that
lithium inhibits IMP half-maximally at 0.80 mEq/L and 1.0 mEq/L respectively. 3,4
-Lithium has been shown to dose-dependently reduce carbachol-stimulated IP3 accumulation
at concentrations as low as 0.1 mEq/L, and half-maximally at 1 mEq/L. 5
 Lithium has been shown to reduce intracellular calcium ion concetrations
This effect was observed in a 7 day protocol of lithium at 1.0 mEq/L. 6
How can lithium influence calcium
signaling?
Therapeutic Concentrations of Lithium 0.6 – 1.2 mEq/L (FDA)
1 - Nonaka S. et al., “Chronic lithium treatment robustly protects neurons in the central nervous system against excitotoxicity by inhibiting N-
methyl-D-aspartate receptor-mediated calcium influx”, Proc. Natl. Acad. Sci. U. S. A., vol. 95, 1998, 2642-2647.
2 - Hashimoto R. et al., “Lithium protection against glutamate excitotoxicity in rat cerebral cortical neurons: involvement of NMDA receptor
inhibition possibly by decreasing NR2B tyrosine phosphorylation”, J. Neurochem., vol. 80., 2002, 589-597.
3 - Hallcher L.M. and Sherman W.R., “The effects of lithium ion and other agents on the activity of myo-inositol-1-phosphatase from bovine
brain”, J. Biol. Chem., vol. 255, 1980, 10896-10901.
4 - Berridge M.J. et al., “Lithium amplifies agonist-dependent phosphatidylinositol responses in brain and salivary glands”, Biochem. J., vol.
206, 1982, 587.
5 - Batty I. and Nahorski S.R., "Differential effects of lithium on muscarinic receptor stimulation of inositol phosphates in rat cerebral cortex
slices", J. Neurochem., vol. 45, 1985, 1514-1521.
6 - Sourial-Bassillious N. et al., "Glutamate-mediated calcium signaling: a potential target for lithium action." Neuroscience. vol. 161, 2009,
1126-1134.

30.  Mg2+ and Li+ have similar ionic radii and charge (Li+ has a slightly smaller
ionic radius compared the Mg2+, allowing Li+ to fit into Mg2+ substrates).
 Given the similarities between the two ions, Li + is implicated in cross-
reacting with substrates regulated by Mg2+. 1-4
 Mg2+ sensitive targets including IMP and NMDA receptor channels – and
potentially, hundreds of other biological substrates regulated by Mg2+, are
potential targets of lithium ions.
 Mg2+ also has similar physical properties with Ca2+ – and this might
account for the inhibitory effects of Mg2+, and Li+, on NMDA receptor
channel mediated Ca2+ influx, and might also account for the possible
influence of Li+ on other calcium signaling pathways.
Lithium, Magnesium, and Calcium
1 - Birch N.J., “Letter: Lithium and magnesium-dependent enzymes. Lancet”, vol. 304, 1974, 965-966.
2 - Amari L., et al., “Comparison of fluorescence, (31)P NMR, and (7)Li NMR spectroscopic methods for
investigating Li(+)/Mg(2+) competition for biomolecules.” Anal. Biochem., vol. 272, 1-7.
3 - Amari L., "Competition between Li+ and Mg2+ in neuroblastoma SH-SY5Y cells: a fluorescence and
31P NMR study", Biophys. J., vol. 76, 1999, 2934-2942.
4- Pasquali L. et al., "Intracellular pathways underlying the effects of lithium", Behav. Pharmacol., vol 21,
2010, 473-492.

31. PHYSICOCHEMICAL PROPERTIES OF SOME ALKALI AND ALKALINE EARTH
ELEMENTS *
(Li) (Mg) (Ca)
Atomic Radius 1.33 1.36 1.74
Crystal Ionic Radius 0.60 0.65 0.99
Corrected Hydrated Radius 3.40 4.65 3.21
Electronegativity 1.0 1.2 1.0
Polarizing Power 2.8 4.7 2.05
* Stern, K. H.; Amis, E. S., Chem. Rev., 1959, 59, 1.
Lithium, Magnesium, and Calcium

32. Feed-Forward Interactions between
Intracellular Calcium and Amyloid
Ca2+ Amyloid
1 - Green K.N. and LaFerla F.M., "Linking calcium to Abeta and Alzheimer's disease", Neuron, vol. 59, 2008,
190-194.
2 - Demuro A. et al., "Calcium signaling and amyloid toxicity in Alzheimer disease", J. Biol. Chem., vol. 285,
2010, 12463-12468.
3 - De Caluwé J. and Dupont G., "The progression towards Alzheimer's disease described as a bistable switch
arising from the positive loop between amyloids and Ca(2+)", J. Theor. Biol., vol. 331, 2013, 12-18.
4 - Texidó L. et al., “Amyloid β peptide oligomers directly activate NMDA receptors” Cell Calcium, vol. 49, 2011,
184-190.
5 - Jensen L.E. et al., "Alzheimer's disease-associated peptide Aβ42 mobilizes ER Ca(2+) via InsP3R-
dependent and -independent mechanisms.“, Front. Mol. Neurosci., vol. 6:36, 2013.

33. Abnormal Ca2+ signaling
through plasma membrane
channels
Extracellular Amyloid
Intracellular Amyloid
Abnormal Ca2+ signaling
through endoplasmic reticulum
channels
Calcium Microdomains

34. Lithium Lithium
NMDA
Antagonism
IMP Inhibition
Lowered Intracellular
Calcium Intrusion from
External Stores
Reduced IP3
Lowered Intracellular
Calcium Intrusion from
Internal Stores
ER Ca2+External Ca2+

35. Lithium BACE Inhibitor
Calcium Signaling
(NMDA Receptor Antagonism)
(IMP Inhibition/IP3 lowered)
Stabilized Intracellular
Calcium
Reduced
Amyloid (Aβ)
Lithium
ER Ca2+External Ca2+ Amyloid (Aβ)
Beta-Secretase
Inhibition

36. In the past decade, two observational studies, one in
Brazil, and one in Denmark, have shown that subjects
with bipolar disorder who are treated with lithium
have a reduced prevalence of dementia. While this
data suggests that continued use of lithium may
reduce the risk for developing Alzheimer’s disease in
asymptomatic adults, confounding factors could have
affected the results. 1,2
1 - Nunes P.V. et al., "Lithium and risk for Alzheimer's disease in elderly patients with bipolar
disorder", Br. J. Psychiatry, vol. 190, 2007, 359-360.
2 - Kessing L.V. et al., "Does lithium protect against dementia?", Bipolar Disord., vol. 12, 2010,
87-94.
Repositioning Lithium for the Prevention
of Neurodegenerative Disease

37. 2015 – The British Journal of Psychiatry
An observational study involving over 40,000
U.S. subjects in 8 states age ≥ 50 showed that
subjects with bipolar disorder who received
301–365 days of lithium had a reduced risk of
developing dementia.
(hazard ratio = 0.77, 95% CI 0.60-0.99)
Gerhard T. et al.., "Lithium treatment and risk for dementia in adults with bipolar disorder:
population-based cohort study”, Br. J. Psychiatry, 2015.

38.  Differential responses to lithium in hyperexcitable neurons from
patients with bipolar disorder. (Mertens J et al.) – Nature 2015.
 Neurons derived from patients with bipolar disorder divide into
intrinsically different sub-populations of neurons, predicting the patients'
responsiveness to lithium. (Stern S et al.) – Molecular Psychiatry 2017
Lithium and Neuronal Hyperactivity

39. ‘Extensive functional analysis showed that intrinsic cell parameters are
very different between the two groups of BD neurons, those derived from
lithium (Li)-responsive (LR) patients and those derived from Li-non-
responsive (NR) patients, which led us to partition our BD neurons into
two sub-populations of cells and suggested two different subdisorders.
Training a Naïve Bayes classifier with the electrophysiological features of
patients whose responses to Li are known allows for accurate
classification with more than 92% success rate for a new patient whose
response to Li is unknown. Despite their very different functional
profiles, both populations of neurons share a large, fast after-
hyperpolarization (AHP). We therefore suggest that the large, fast AHP is
a key feature of BD and a main contributor to the fast, sustained spiking
abilities of BD neurons. Confirming our previous report with fibroblast-
derived DG neurons, chronic Li treatment reduced the hyperexcitability
in the lymphoblast-derived LR group but not in the NR group,
strengthening the validity and utility of this new human cellular model
of BD.’ (Stern S et al.) – Molecular Psychiatry 2017
Lithium and Neuronal Hyperactivity

40. 1. The membrane voltage-gated calcium ion channel CALHM1 has been
linked to intracellular Ca2+ regulation and maintaining Ca2+ homeostasis in
neurons - in response to extracellular Ca2+ concentration variations.
2. Mg2+ has been shown to influence CALMH1 gating (IC50 = 3.26 mM; Hill
coefficient = 2.3), but at a lower affinity compared to Ca2+ (Ma Z et al. 2012);
- according to the authors, the dose response relation for Mg2+ is similar in
shape to that of Ca2+ at the same holding potential, suggesting that both
cations bind to the same CALHM1 sites and regulate CALHM1 channel
gating by a similar mechanism.
3. CALHM1 receptors have been shown to be similarly regulated by Ca2+ and
Mg2+ (Tanis JE et al. 2013).
4. Given the influence by Ca2+ and Mg2+ on CALHM1, CALHM1 might
represent an additional candidate membrane target of Li+ that could
potentially influence neuronal calcium signaling by binding to and
antagonizing the flow of Ca2+ into neurons through CALHM1 channels,
lowing intracellular Ca2+ levels, and modulating neuronal hyperexcitability.
Calcium Homeostasis Modulator 1 (CALHM1)
• Ma Z. et al., “Calcium homeostasis modulator 1 (CALHM1) is the pore-forming subunit of an ion channel that mediates
extracellular Ca2+ regulation of neuronal excitability” Proc. Natl. Acad. Sci. U. S. A., vol. 109, 2012, E1963-71.
• Ma Z. et al, “Calcium homeostasis modulator (CALHM) ion channels” Pflugers Arch., 2016.
• Tanis J.E. et al, “CLHM-1 is a functionally conserved and conditionally toxic Ca2+-permeable ion channel in
Caenorhabditis elegans” J. Neurosci., vol. 33, 2013, 12275-86.

41.  In a clinical trial, subjects with amnesic mild
cognitive impairments treated with levetiracetam
showed:
 (1) improvements in memory task performance
 (2) reduced rates of elevated hippocampal dentate
gyrus/CA3 activation.
Levetiracetam and Neuronal Hyperactivity
Bakker A. et al., “Response of the medial temporal lobe network in amnestic mild cognitive impairment to
therapeutic intervention assessed by fMRI and memory task performance”, Neuroimage Clin., vol 7,
2015, 688-698.

42. Levetiracetam and Calcium Signaling
Nagarkatti N. et al., “Levetiracetam inhibits both ryanodine and IP3 receptor activated calcium induced calcium release in
hippocampal neurons in culture”, Neurosci. Lett., vol. 436, 2008, 289-293.
Fukuyama K. et al., “Levetiracetam inhibits neurotransmitter release associated with CICR” Neurosci Lett., vol. 518, 2012, 69-74.
By inhibiting IP3R and RyR calcium induced calcium release,
Levetiracetam can reduce calcium ion influx from internal ER stores. 1,2

43. Levetiracetam + BACE inhibitor *
* U.S. Patent Pending #US 20160213645 A1
IP3 receptor CICR Inhibition
Ryanodine receptor (RyR) CICR Inhibition
Beta-Secretase
Targets Include:

44. Levetiracetam BACE Inhibitor
Calcium Signaling
(IP3R CICR Inhibition)
(RyR CICR Inhibition)
Decreased Calcium Induced
Calcium Release (CICR) from
ER stores
Reduced Amyloid
Amyloid (Aβ)ER Ca2+
Beta-Secretase
Inhibition
Stabilized Intracellular
Calcium

45. Memantine + Levetiracetam + BACE Inhibitor *
Combining Memantine + Levetiracetam + BACE
inhibitor:
A. to influence calcium signaling from both external
and internal calcium stores – for a lithium-like
effect with an improved side-effect profile, and
reduced monitoring
B. to inhibit the cleavage of Amyloid Precursor
Protein (APP) by beta-secretase
* U.S. Patent Pending #US 20160213645 A1

46. Targets Include:
NMDA Receptors
IP3 receptor CICR Inhibition
Ryanodine receptor (RyR) CICR Inhibition
Beta-Secretase

47. By antagonizing NMDA receptors, Memantine can inhibit the
stimulation of neurons and inhibit external calcium ion influx.
Memantine, NMDA Receptors, and External Calcium Influx

48. Memantine - 2018
 Kodis, Erin J. et al. “N-methyl-D-aspartate receptor–mediated
calcium influx connects amyloid-β oligomers to ectopic neuronal
cell cycle reentry in Alzheimer's disease.” Alzheimer's & Dementia,
2018. A study that tested the hypothesis that Aβ oligomer
(AβO)-stimulated calcium entry also drives neuronal cell cycle re-
entry (CCR), a prelude to neuron death in AD.
‘Results:
In cultured neurons, Aβ oligomer (AβO)-stimulated cell cycle re-entry (CCR) was blocked
by NMDAR antagonists, total calcium chelation with 1,2-Bis(2-aminophenoxy)ethane-
N,N,N′,N′-tetraacetic acid tetrakis (acetoxymethyl ester) (BAPTA-AM), or knockdown of
the NMDAR subunit, NR1. NMDAR antagonists also blocked the activation of calcium-
calmodulin-dependent protein kinase II and treatment of Tg2576 AD model mice with the
NMDAR antagonist, memantine, prevented CCR.
Discussion:
This study demonstrates a role for AβO-stimulated calcium influx via NMDAR and CCR in
AD and suggests the use of memantine as a disease-modifying therapy for presymptomatic
AD. ’

49. Levetiracetam BACE Inhibitor
Calcium Signaling
(NMDAR Ca2+ influx antagonism) +
(IP3R + RyR CICR Inhibition)
Stabilized Intracellular
Calcium
Reduced
Amyloid
Memantine
ER Ca2+External Ca2+ Amyloid (Aβ)
Beta-Secretase
Inhibition

50. Alzheimer's Association National Plan
Milestone Workgroup - 2014
PubMed ID 25341459 - http://www.ncbi.nlm.nih.gov/pubmed/25341459

51. Alzheimer's Association National Plan
Milestone Workgroup - 2014
Milestone A: Convene an advisory meeting of experts
from the pharmaceutical industry, government,
academia, the FDA, and the nonprofit sector to advance
rational drug repositioning and combination therapy
based on translational bioinformatics and network
pharmacology approaches and to explore opportunities
for new public-private partnerships to facilitate drug
rescue/repurposing and combination therapy.
Timeline: 1 yr - 2014

52. Alzheimer's Association National Plan
Milestone Workgroup - 2014
Milestone B: Initiate research programs for
translational bioinformatics and network
pharmacology to support rational drug repositioning
and combination therapy from discovery through
clinical development.
Timeline: 3–5 yrs - 2015–2019

53. Alzheimer's Association National Plan
Milestone Workgroup - 2014
Milestone C: Initiate early clinical development for at
least 6 existing drugs or drug combinations for the
treatment or prevention of AD.
Timeline: 2-4 yrs - 2018–2021

54. Wallace J., “Calcium dysregulation, and lithium treatment
to forestall Alzheimer's disease - a merging of hypotheses”,
Cell Calcium, vol. 55, 2014, 175-81.
Additional Reading

55. James Wallace
Thank you