New Therapies for Spinal Cord Injury Ann M. Parr, MD, PhD, FAANS, FRCSC Director of Spinal Neurosurgery Assistant Professor University of Minnesota

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1 New Therapies for Spinal Cord Injury Ann M. Parr, MD, PhD, FAANS, FRCSC Director of Spinal Neurosurgery Assistant Professor University of Minnesota Neurological Conditions for Stem Cell Therapy Application Traumatic brain or spinal cord injury Stroke Demyelinating diseases multiple sclerosis Degenerative diseases amyotrophic lateral sclerosis (ALS), Parkinson s disease Congenital diseases - adrenoleukodystrophy Epidemiology of Spinal Cord Injury Lifetime cost of medical care for 25 year old with high cervical injury = $3 million Most common years old, average age 42 Male : female = 4 : 1 Cervical spine = 56% Causes: Sportsrelated Violence Motor Vehicle Accidents Falls without permission. 1

2 Challenges in SCI Research Multiple mechanisms of injury All injuries are not the same: Acute versus chronic injury Complete versus incomplete injury Cervical versus thoracic injury What are goals of recovery? What is clinically meaningful? Limited funding care versus cure? Initial Management Currently - management is supportive Avoid low blood pressure Intensive Care Unit Early surgery for spinal cord compression Controversial use of steroids - reduce inflammation but have significant side effects Controversial use of cooling - undergoing clinical trial Rehabilitation No effective and available treatments.. Rehabilitation Currently the most important treatment 1) Works to prevent deconditioning and optimize remaining function, optimize health 2) Brain and spinal cord plasticity have recently been appreciated - enhanced with rehabilitation therapy? without permission. 2

3 Stage of Injury Immediate <2hrs Acute <48hrs Subacute <14 days Intermediate <6 months Chronic >6 months Key Processes Primary injury Severing of axons Hemorrhage Necrosis Microglial activation Release of factors Edema Lipid peroxidation Excitotoxicity Necrosis Neutrophils Leaky blood vessels Demyelination Neuronal death Macrophage infiltration Formation of astroglial scar Repair of leaky vessels and resolution of edema Cyst formation Lesion stabilization Prolonged axonal degeneration Spared demyelinated axons Potential plasticity? Targets for Therapy Neuroprotection Neuroprotection Immune effects Remyelination Remyelination Glial scar degradation Rehab Prostheses Potential Beneficial Mechanisms of Transplanted Cells in Spinal Cord Injury Replacement of damaged cells Protection from further injury from inflammation and other processes ( Neuroprotection ) Creation of a favorable environment for regeneration Remyelination Cell Based Therapies Cell Source can be adult, fetal or embryonic Some of these are autografts, some are allografts Obviously most autografts are from adult cells, since most people do not have their own fetal/embryonic cells banked Transplanted cell types Schwann cells Olfactory ensheathing cells (OECs) Bone marrow stromal cells and hematopoietic stem cells Neural stem cells and glial progenitors (NSCs/OPCs) without permission. 3

4 Transplanted Cell Types Cell Type Cell Source Autologous? Normal function Schwann Cell Peripheral nerve Yes, but takes weeks to grow Olfactory Ensheathing Cell BMSC and Hematopoietic Cell Olfactory mucosa Bone marrow or blood Yes, obtained more easily Yes, very easy to obtain, approved Myelinate PNS axons Bridge PNS-CNS from olfactory mucosa to olfactory bulb Generate blood cells, play role in immune system Neural Stem/Progenitor Cell Central nervous system No Generate brain and spinal cord Transplanted Cell Types Cell Type Mechanism of Action Issues Trials Schwann Cell Olfactory Ensheathing Cell BMSC and Hematopoietic Cell Neural Stem/Progenitor Cell Remyelinate CNS Promote axon sprouting Integrate into glial scar to aid axon growth Anti-inflammatory, trophic support, NOT cell replacement Cell replacement, plus all of the above May not allow regenerating axons to reenter CNS Mixed results, heterogeneous cell population Heterogeneous cell population, mechanism poorly understood Cell rejection, mechanism poorly understood Gartner Hype Cycle without permission. 4

5 clinicaltrials.gov 31 studies listed, removal of unknown/terminated 2 Schwann cell, no OEC, 22 MSC (incl. cord blood and adipose derived), and 8 NSC trials (incl. OPCs) 3 NSC/OPC trials of note in the USA Neuralstem Stem Cells, Inc. Geron/Asterias Biotherapeutics Clinical Trials - Neuralstem Fetal derived human spinal cord neural stem cells Phase 1 safety trial in ALS completed (NCT ) Chronic SCI (1-2 years), complete mid-thoracic injuries Open label, single site safety study Primary outcomes were adverse events over 6 months, secondary outcomes were graft survival Results Safe Future Plans Project stalled, stock prices dropped after failed trial with a depression drug Glass JD, Boulis NM, Johe K, Rutkove SB, Federici T, Polak M, Kelly C, Feldman EL. Lumbar intraspinal injection of neural stem cells in patients with amyotrophic lateral sclerosis: results of a phase I trial in 12 patients. Stem Cells Jun;30(6): doi: /stem Riley J, Federici T, Polak M, Kelly C, Glass J, Raore B, Taub J, Kesner V, Feldman EL, Boulis NM. Intraspinal stem cell transplantation in amyotrophic lateral sclerosis: a phase I safety trial, technical note, and lumbar safety outcomes. Neurosurgery Aug;71(2):405-16; discussion 416. doi: /NEU.0b013e31825ca05f. Clinical Trials Stem Cells, Inc. Fetal derived human neural stem cells Demonstrated safety (Phase 1) in mid-thoracic SCI patients (>6 weeks) Trial number (NCT ) Pathway Trial Chronic SCI (4-24 months), cervical spinal cord injury (C5-7), Grade B Single-blind, randomized, Phase II study (safety and efficacy) Primary outcome change in baseline of upper extremity motor score Results Study terminated early - unlikely to achieve primary outcome company assets sold to Chinese Group Emerging Safety of Intramedullary Transplantation of Human Neural Stem Cells in Chronic Cervical and Thoracic Spinal Cord Injury. Levi AD, Okonkwo DO, Park P, Jenkins AL 3rd, Kurpad SN, Parr AM, Ganju A, Aarabi B, Kim D, Casha S, Fehlings MG, Harrop JS, Anderson KD, Gage A, Hsieh J, Huhn S, Curt A, Guzman R. Neurosurgery. 2017; PubMed [journal]pmid: without permission. 5

6 Clinical Trials Asterias Biotherapeutics Human embryonic stem cell derived oligodendrocyte progenitor cells Safety trial in acute (<11 days) complete thoracic injury Trial number (NCT ) - SCIStar Complete subacute SCI (14-30 days), cervical spinal cord injury (C5-7) Primary outcome number of adverse events Future Plans 6 month safety data due Spring 2018 Plan to move forward with a Phase 2 trial similar to the Pathway study 2019 Cells of the Brain and Spinal Cord Three cell types make up the central nervous system (brain and spinal cord): NEURONS - cells that carry signals to muscles and to brain along axons (axons are the wiring of the spinal cord) ASTROCYTES - supportive cells in the brain and spinal cord OLIGODENDROCYTES - provide insulation to the axons called myelin that allows them to signal more efficiently without permission. 6

7 Why Neural Stem Cells? Neural stem cells: Self-renew Give rise to all three CNS cell types In some amphibians NSCs divide and differentiate to regenerate the injured cord In mammals, these cells divide in response to injury but have limited regenerative ability Functional benefit shown in both small and large animal models Long-term Goal of our Research Initiate a Phase I clinical trial using autologous neural stem/progenitor cells to restore and preserve function following chronic SCI Back to the Bench the Promise of ipscs Current trials use Embryonic or Fetal Stem Cells Allogeneic, requiring immunosuppression to prevent rejection Ethical controversy Uncharacterized neural progenitor cells We propose using fully defined, autologous OPCs derived from adult stem cells Autologous Induced Pluripotent Stem Cells (ipscs) derived from patient s skin is used as an intermediate step No rejection without permission. 7

8 Personalized medicine approach to treating spinal cord injury Autologous ipsc-derived Neural Stem Cell Transplantation Patient attends clinic Routine skin biopsy UMN MCT Facility cgmp fibroblasts banked UMN Stem Cell Institute cgmp ipsc reprogramming Patient receives personalized treatment Olig2 Sox10 cgmp compliant ipsc to OPC differentiation Nanog Characterized Neural Progenitor Cells OPCs and snpcs Oligodendrocyte progenitor cells (OPCs) are the precursor cells to oligodendrocytes, the cells that myelinate axons in the CNS. Spinal neuronal progenitor cells (snpcs) will generate spinal neurons, which could act as relays across the site of injury. Neural Progenitor Cell Therapy Oligodendrocyte Progenitor Cells (OPCs) Axons are demyelinated following injury OPCs can be grown in vitro Migrate and differentiate after transplantation Will remyelination occur? Spinal Neuronal Progenitor Cells (snpcs) Give rise to spinal neurons Can form synaptic connections Can they form functional relays? without permission. 8

9 SC121 Sox10 SC121 Olig2 ipsc-derived OPCs after transplantation into injured athymic nude (ATN) rat spinal cord D Site of injection Injury site Site of injection Injury site V mipsc derived OPCs expressing egfp 8 weeks after injury and are migrated extensively throughout injury site hipsc derived OPCs (detected 1mmwith antibody) 4 weeks after injury and also migrate extensively throughout injury site Transplanted human ipsc-derived OPCs maintain oligodendrocyte identity 2 weeks after human OPC injection in acute rat injury How to recapitulate OPC or snpc differentiation using ips cells snpcs Spinal neurons Undifferentiated ipsc Neural Progenitor pmn domain patterned Neural Progenitor OPCs Oligodendrocytes without permission. 9

10 % of Grafted Cells Manufacturing Protocol for spinal Neurons from hipscs Neural pmn domain Motor neuron ipscs Induction ventralization maturation d0 d3 d11 d17 d28 CDM Essential 6 rvitronectin 250nM LDN mM SB mM CHIR nM Retinoic Acid N2 B27 rlaminin 1mM SAG 10mM DAPT Passage Passage Passage 1:6 1:6 1:6 d9 d17 d21 d28 Pax6 Sox1 Olig2 Olig2 Hb9 Hb9 biii tubulin cgmp compliant, adherent, fully scalable Transplanting hipsc derived snpcs into the ATN rat after subacute spinal cord injury Spinal cord Injury Cell Transplant 12 weeks Analysis of transplanted cells and injury environment Histology 7-9 days Functional testing BBB scores Ladderwalk RNA expression Do the cells survive after transplantation? Where do they migrate to and what is their fate? Does the cell transplantation change the functional recovery from the injury? Does transplantation of the cells modify the injury environment? Human snpcs 12 weeks after transplant in subacute rat injury A B C D HNA GFAP HNA Nestin DAPI HNA NeuN HNA MAP2 60% 50% 40% 30% 20% 10% 0% NeuN Map2 Nestin GFAP Cell survival is excellent 12 weeks after transplantation 12 weeks after injury the transplanted cells are a mix of mature neurons, immature neural progenitors and <5% astrocytes Cell bodies remain near the injection site and project axons throughout the injury without permission. 10

11 Transplantation of spinal Neuronal Progenitor Cells into Chronic Rat Spinal Cord Injury Athymic nude rat Injection Injury Injection SC121 1mm 3 x 10 5 pmnpcs injected 8 weeks after injury SC121 detected 4 weeks after injection HNA NeuN The majority of cells become human neurons SC121 Progeny of the transplanted cells project axons throughout injury site SC121 biii tub What about the Glial Scar in Chronic Injury? Cellular origin of glial scar formation following spinal cord injury Astrocytes (blue), ependymal cells (purple) and NG2+ progenitor cells (green) can give rise to heterogeneous scarforming astrocytes within the glial scar Yuna & He (2013) Neurosci Bull Minimally invasive glial scar ablation using rose Bengal In collaboration with Dr Eric Holmberg and the Spinal Cord Society Rose Bengal Spinal cord Injury 6 weeks (4,5,6,7-tetrachloro-2',4',5',7'-tetraiodofluorescein) FDA approved for conjunctival staining Re-purposing for new use Injection with rose Bengal Photo ablation 8 minutes 24 hours or 8 days Immunohistochemical Analysis Can minimally invasive photo ablation after injection of rose Bengal remove the glial scar in a model of chronic spinal cord injury without further damaging the cord? without permission. 11

12 GFAP Photo ablation after rose Bengal treatment removes glial scar components without further damage to the cord Control B + Rose-bengal A B Astrocytic Matrix Fibrotic Spinal cords were examined for components of the glial scar 24h post treatment with either saline or one of 3 rose Bengal derivatives. Similar results were detected 8 days after treatment. Patil N, Truong V, Dutton J, Holmberg E, and Parr AM. Safety and Efficacy of Rose Bengal Derivatives for Glial Scar Ablation in Chronic Spinal Cord Injury, accepted to Journal of Neurotrauma, January Epidural Stimulation Spinal cord stimulation utilized for many years for chronic pain, failed back surgery, etc. Stimulation below the injury level improves function how? Suggested to stimulate reflexes, does NOT directly activate motor neurons Altering spinal cord excitability enables voluntary movements after chronic complete paralysis in humans Angeli et al, Brain 2014 without permission. 12

13 Epidural Spinal Cord Stimulation 37 Epidural Spinal Cord Stimulation Capogrosso Barriers to Clinical Use Reproduction Optimization Effectiveness 39 without permission. 13

14 Epidural Stimulation After Neurological Damage Dr. David Darrow Dr. Uzma Samadani Human Trial: Goals 1. Verify previous results 2. Remove barriers to deployment 3. Begin to understand autonomic effects 42 without permission. 14

15 Inclusion Criteria 22 years of age or older Able to undergo the informed consent/assent process Stable, motor-complete paraplegia Discrete spinal cord injury between C6 and T10 ASIA A or B Spinal Cord Injury Classification Medically stable in the judgement of the principal investigator Intact segmental reflexes below the lesion of injury Greater than 1 year since initial injury and at least 6 months from any required spinal instrumentation Willing to attend all scheduled appointments Exclusion Criteria Diseases and conditions that would increase the morbidity and mortality of spinal cord injury surgery (e.g. cardiopulmonary issues) Inability to withhold antiplatelet/anticoagulation agents perioperatively Significant dysautonomia that would prohibit rehabilitation or assisted standing or any history of CVA or MI associated with autonomic dysreflexia.. A single tilt table test with syncope, presyncope, or SBP < 50 or >200. Other conditions that would make the subject unable to participate in testing/rehabilitation in the judgment of the principal investigator Current and anticipated need for opioid pain medications or pain that would prevent full participation in the rehabilitation program in the judgement of the principal investigator Exclusion Criteria Continued Clinically significant mental illness in the judgment of the principal investigator Botulinum toxin injections in the previous 6 months Volitional movements present during EMG testing in bilateral lower extremities Unhealed spinal fracture Presence of significant contracture Presence of pressure ulcers Recurrent urinary tract infection refractory to antibiotics Current Pregnancy without permission. 15

16 Mobile App 47 Primary Outcome Volitional movement: surface EMG Motor Control Assessment (BMCA) Volitional Response Index Magnitude 48 without permission. 16

17 Preliminary Results 49 Patient 1 52 years old SCI from fall T8 AIS A 11 years from injury No Dysautonomia on tilt table testing Does minimal therapy Significant atrophy without permission. 17

18 without permission. 18

19 Patient 2 48 F SCI from motorcycle accident 5 years since injury T4 AIS A Hypotensive during tilt table testing Does therapy 1-2x/week without permission. 19

20 Key take aways Oldest patients First female patients 5 and 11 years from injury Most severe appearing spinal cords Restoration of some volitional movement right after surgery No adverse hypertension from stimulation Restoration of normal blood pressure for patient 2 without permission. 20