2DG – A Familiar Antiglycolytic Glucose-analog With Novel Anticonvulsant Properties

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Thomas Sutula, MD, PhDDetling Professor and ChairDepartment of Neurology University of Wisconsin

Chief Scientific OfficerNeuroGenomeX, Inc.Madison, WI

2DG: a glucose analog differing from glucose only by removal of Oxygen at the 2-position

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glycolytic inhibitorglycolytic inhibitor

2DG: a glucose analog differing from glucose only by removal of Oxygen at the 2-position

2DG transiently inhibits glycolysis by blocking the isomerization step from glucose-6P to fructose-6P

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focal brain deliveryfocal brain deliveryduring seizuresduring seizures

(18F-2DG PET scan(18F-2DG PET scanIsrael & Fishman 1999)Israel & Fishman 1999)

focal brain deliveryfocal brain deliveryby stimulation by stimulation

(3H-2DG autoradiogram(3H-2DG autoradiogramSutula et al.)Sutula et al.)

glycolytic inhibitorglycolytic inhibitor

2DG: a glucose analog differing from glucose only by removal of Oxygen at the 2-position

2DG transiently inhibits glycolysis by blocking the isomerization step from glucose-6P to fructose-6P

Activity-dependent uptake loads 2DG into areas of neural circuitry with increased metabolic demands

Completed Preclinical efficacy studies

In vivo studies in acute and chronic models of epilepsy

Acute anticonvulsant action

• protection against seizures evoked acutely by 6Hz stimulation

(ED50 = 79.5 mg/kg)

• protection against audiogenic seizures in Fring’s mice

(ED50 = 206 mg/kg)

• 2-fold slowing of latency to status epilepticus onset by pilocarpine

Chronic antiepileptic action

• 2-fold slowing of kindled seizure induction and progression from different brain sites (37.5 mg/kg)

• Effective against seizure progression when administered as long as 10 min AFTER a seizure!

Completed Preclinical efficacy studies

In vivo studies in acute and chronic models of epilepsy

In vitro studies in hippocampal slices

Acute anticonvulsant action

• protection against seizures evoked acutely by 6Hz stimulation

(ED50 = 79.5 mg/kg)

• protection against audiogenic seizures in Fring’s mice

(ED50 = 206 mg/kg)

• 2-fold slowing of latency to status epilepticus onset by kainic acid

Chronic antiepileptic action

• 2-fold slowing of kindled seizure induction and progression from different brain sites (37.5 mg/kg)

• Effective against seizure progression when administered as long as 10 min AFTER a seizure!

Implies that actions of 2DG at the cellular level are potentially “broad-spectrum”

against different mechanisms of network synchronization

2DG reduces epileptic discharges evoked by :

• 7.5 mM K+ (ictal and interictal)• bicuculline (GABAa antagonist)• 4AP (K+ channel antagonist)• DHPG (metabotropic glutamate agonist)

2DG has “disease-modifying” effects against progression of seizures and long-term consequences of poorly controlled epilepsy

2DG slows progression of kindled seizures by 2-fold 2DG slows progression of kindled seizures by 2-fold

also at 37.5 mg/kgalso at 37.5 mg/kg

NUMBER OF SEIZURES

1 5 30 90-100

APOPTOSISNEUROGENESIS

SPROUTING HIPPOCAMPAL SCLEROSISMEMORY LOSS

REDUCEDINHIBITION

+ + +

SPONTANEOUSSPONTANEOUS SEIZURES SEIZURES

“Disease- modifying” actions of 2DG against progressive adverse effects of repeated seizures

NUMBER OF SEIZURES

1 5 30 90-100

APOPTOSISNEUROGENESIS

SPROUTING HIPPOCAMPAL SCLEROSISMEMORY LOSS

REDUCEDINHIBITION

+ + +

SPONTANEOUSSPONTANEOUS SEIZURES SEIZURES

+ 2DG

“disease-modifying” antiepileptic actions with 2DG administration as long as 10 minute AFTER seizures

“disease-modifying” antiepileptic actions with 2DG administration as long as 10 minute AFTER seizures

implications for novel applications including status epilepticus, seizure clusters, Lennox-Gastaut syndrome

Chronic “disease-modifying” antiepileptic effects of 2DG are associated with alterations of

seizure-induced gene expression by novel mechanisms of metabolic

transcriptional regulation

required for kindling progression

• Used since 1979 in humans as PET imager (18F-2DG)

• >20 investigator-initiated clinical trials in man (~700 normal controls and patients) with no systematic side effects

• FDA Approved IND tox packages from U.Iowa and Kettering available to NGX as “right of reference” letters

• 2004 completed Phase I 2004 completed Phase I clinical trial for adjuvant clinical trial for adjuvant cancer chemotherapy at cancer chemotherapy at doses up to doses up to 200 mg/kg200 mg/kg was was without adverse toxicity without adverse toxicity (Threshold Pharma)(Threshold Pharma)

• Hundreds of published Hundreds of published animal studiesanimal studies

Previous 2DG experience

TOXICITY PROFILE OF 2DG

• Used since 1979 in humans as PET imager (18F-2DG)

• >20 investigator-initiated clinical trials in man (~700 normal controls and patients) with no systematic side effects

• FDA Approved IND tox packages from U.Iowa and Kettering available to NGX as “right of reference” letters

• 2004 completed Phase I 2004 completed Phase I clinical trial for adjuvant clinical trial for adjuvant cancer chemotherapy at cancer chemotherapy at doses up to doses up to 200 mg/kg200 mg/kg was was without adverse toxicity without adverse toxicity (Threshold Pharma)(Threshold Pharma)

• Hundreds of published Hundreds of published animal studiesanimal studies

Previous 2DG experience

• No overt systemic toxicity in rats treated for 6 months at 500 mg/kg/day

• No effect on spatial memory in rats after 2 weeks at 1 gm/kg/day

• No effect on open field activity at minimal effective dose of 37.5 mg/kg

Tox Observations

TOXICITY PROFILE OF 2DG

• Used since 1979 in humans as PET imager (18F-2DG)

• >20 investigator-initiated clinical trials in man (~700 normal controls and patients) with no systematic side effects

• FDA Approved IND tox packages from U.Iowa and Kettering available to NGX as “right of reference” letters

• 2004 completed Phase I 2004 completed Phase I clinical trial for adjuvant clinical trial for adjuvant cancer chemotherapy at cancer chemotherapy at doses up to doses up to 200 mg/kg200 mg/kg was was without adverse toxicity without adverse toxicity (Threshold Pharma)(Threshold Pharma)

• Hundreds of published Hundreds of published animal studiesanimal studies

Previous 2DG experience

• No overt systemic toxicity in rats treated for 6 months at 500 mg/kg/day

• No effect on spatial memory in rats after 2 weeks at 1 gm/kg/day

• No effect on open field activity at minimal effective dose of 37.5 mg/kg

Tox Observations

Based on this favorable prior history, we are hopeful for:

1. FDA approval for an abbreviated pre-IND toxicology package

2. FDA approval for combined Phase I/II studies in epilepsy patients

TOXICITY PROFILE OF 2DG

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Possible clinical trials/applications for 2DG

1. Photosensitivity trial

2. Conventional six month double blind add-on cross-over trial in refractory patients with partial complex and secondary generalized seizures

3. Double blind trial in adult patients with Lennox-Gastaut syndrome (potential orphan drug indication)

4. Administration at onset of seizures in patients experiencing seizure clusters

5. Double blind add on trial in refractory status eplilepticus

6. Implanted device - 2DG combination trials (stimulation-loading of 2DG into

epileptogenic circuitry)

• Efficacy against focal seizures and secondary generalized seizures in preclinical models

• Relatively short t1/2 of ~ 40 minutes

• Rapid absorption by both oral and parenteral routes

• Enhanced activity-dependent focal loading in epileptogenic brain regions maximized around the time of seizure

Relevant 2DG Properties Clinical Trial Options

Licensed from Wisconsin Alumni Research Foundation (WARF) to NeuroGenomeX

• license agreement* includes all WARF “therapeutic use” patents of 2DG

1) “Metabolic-Based Methods for Modulating Gene Expression” P05137US (Priority date- 2/14/2005)

claims: USE of 2DG for prevention of cancer metastasis and treatment of other systemic conditions status: patent issued

2) “Compounds and Methods for Treating Seizure and Paroxysmal Disorders” P04134US (Priority date- 6/17/2004)

claims: USE of 2DG for treatment of seizures and neuropathic pain status: pending

Freedom-to-operate: favorable opinion provided in 2005

3) “Methods and Compounds for Treating Seizure Disorders” P05095US (Priority date - 3/25/2005)

claims: Another metabolic-based method for therapeutic developmentstatus: awaiting office action

INTELLECTUAL PROPERTY

* License includes all US and foreign related patent applications

2DG in the drug development pipeline: approaching IND and Phase I/II

2DG

2DG in the drug development pipeline: approaching IND and Phase I/II

• novel acute and chronic anticonvulsant mechanisms based on metabolic regulation and long-term alterations

in seizure-related gene expression

• broad spectrum of action at the cellular level against mechanisms of network synchronization

• distinctive spectrum of activity against preclinical screening models

• disease-modifying actions against progressive effects of seizures

• activity-dependent delivery to regions of epileptic activity

• potentially novel methods of delivery: post-seizure, with device therapies

• favorable preclinical toxicity and human use toxicity profile