Future Clinical Development Plan forAST-OPC1 Edward Wirth, III, M.D., Ph.D. Chief Medical Officer Investor DayMay 8, 2015  * 

 Work of the SCOPE Consortium Has Defined Clinical Development Path in Complete Cervical Spinal Cord Injury  *  Target Product Profile for AST-OPC1 in Complete Cervical SCI: Increase of ≥20% in the percentage of patients regaining two or motor levels of function  Enables powering of trial with only ~200 subjectsTranslates into clinically significant improvements in ability to self-care, significant reductions in cost of care  Steeves et al., Top Spinal Cord Inj Rehabil 2012; 18(1): 1-14  

 AST-OPC1 Phase 1/2a Trial: Expansion Cohort  *  Cohort 1:3 subjects2 million cells  Cohort 2:5 subjects10 million cells  Cohort 3:5 subjects20 million cells  Expansion Cohort*:Up to 27 additional patients10 and/or 20 million cellsAdaptive Design  File IND amendment for study expansion based on initial safety data in Cohort 2  Q1’15: Study initiates  Q3’15: Dose escalation  Q1’16: Dose escalation  1H’16: 6 mo efficacy, cohort 2  Open label trial enables use of adaptive design for selection of dose in expansion cohortWork of SCOPE enables comparison to robust historical outcomes databases  *Subject to FDA clearance for expansion from 13 to 40 subjects 

 AST-OPC1 Future Clinical Development Plan in Complete Cervical SCI  *  Cohort 13 subjects with C5-C7 cervical SCI Dose 2x106 AST-OPC1  Objectives of TrialEstablish safety of AST-OPC1 in cervical sensorimotor complete SCIAssess effects on upper extremity motor functionInvestigate effects on additional measures of neurological function  Cohort 25 subjects with C5-C7 cervical SCIDose 1x107 AST-OPC1  Cohort 35 subjects with C5-C7 cervical SCIDose 2x107 AST-OPC1  Dose Escalation  Dose Escalation  Breakthrough therapy designationPhase 2 expansion cohortRandomized pivotal trial in cervical complete SCITrials in additional indications (e.g., MS, Stroke)  Results from Phase 1/2 Clinical Trial Could Enable:  Confirm low-dose safety in cervical SCI  Confirm mid-dose safetyEfficacy readouts at 6m & 12m  Confirm high-dose safetyEfficacy readouts at 6m & 12m 

 A Pivotal Randomized Trial Could be Feasible with 200 Total Subjects  *  Feasible number that could be enrolledin a pivotal SCI trial in North America  Analysis: A 200 patient pivotal trial (100 per arm) could show a statistically significant difference in self-care ability (functional endpoint) if >40% of AST-OPC1 recipients recover>= 2 motor levels at 6 months post-injection 

 AST-OPC1: Follow-on Indications in Other Neurodegenerative Diseases  Revascularization of Injury Site  Indication Multiple SclerosisWhite Matter Stroke  RationaleRemyelination of axons in lesion site could restore function Leverage safety data & delivery system for OPC1 transplantation in spinal cordOligodendroglial dysfunction prominent in white matter (subcortical) stroke  StatusPOC in primate model of chemical demyelination (Jeff Kocsis, Yale)Clinical advisory panel heldPreclinical collaboration underway to test AST-OPC1 in a white matter stroke model(Tom Carmichael, UCLA)  * 

 *  Asterias Milestones and Newsflow Next 24 Months  Asterias 24 Month Milestone and Catalyst Outlook  Timing  Milestone / Catalyst / Event  Q4’14 - completed  Sign CIRM grant – triggers disbursement of CIRM funds  Q1’15 – completed  Initiate AST-OPC1 Phase 1/2a clinical trial  AST-OPC1  AST-OPC1  Q3’15  Safety readout from 2M cell cohortInitiation of 10M cell cohort  H1’16  6 month efficacy data from 10M cell cohort  H2’16  12 month efficacy data from 10M cell cohort6 month efficacy data from 20M cell cohort