Asterias Biotherapeutics Completes Enrollment and Dosing for the First Efficacy Cohort of the AST-OPC1 SCiSTAR Phase 1/2a Clinical Trial in Complete Cervical Spinal Cord Injury

FREMONT, Calif., July 12, 2016 /PRNewswire/ -- Asterias Biotherapeutics, Inc. (NYSE MKT: AST), a biotechnology company with three clinical-stage development programs focused on the emerging field of regenerative medicine, today announced completion of enrollment and dosing of five patients in the first efficacy cohort of the SCiSTAR study, a Phase 1/2a clinical trial evaluating activity of escalating doses of AST-OPC1 (oligodendrocyte progenitor cells) in newly injured patients with sensory and motor complete cervical spinal cord injury (SCI). In this cohort, five patients (constituting the minimum number required to complete the cohort) were each administered 10 million AST-OPC1 cells.  This is the second of three cohorts in the study and it represents the first cohort in which patients have been administered a dose high enough to fall within the potentially efficacious range predicted from extensive preclinical studies. The company expects to report top-line six-month efficacy and safety results from this five patient cohort in January 2017.  Of note, the company recently received clearance from the U.S. Food and Drug Administration (FDA) to expand enrollment in the study, including up to three additional patients into this 10 million cell cohort for a total of eight patients.

The SCiSTAR study is being funded in part by a $14.3 million grant from the California Institute of Regenerative Medicine.

In addition, Asterias provided an update on observations from the earlier, very low dose safety cohort of three patients who were administered two million cells within the same study.  All three patients have completed their six-month follow up visit, with the first patient also having completed the 12-month follow up visit.  There have been no serious or unexpected adverse events related to AST-OPC1, the administration procedure or the accompanying short course of low-dose immunosuppression.  In this safety cohort, all three patients have exhibited improved upper extremity motor function relative to their baseline exams.  The company will compare the degree of motor function improvement observed to-date in this very low dose safety cohort against the 10 million cell efficacy cohort once that group reaches 6 months of follow up in order to begin to evaluate the dose-response of AST-OPC1.  The company will also conduct an additional evaluation of dose-response once 12-month efficacy results are available for this 10 million cell cohort in mid-2017.

"Successful completion of enrollment and dosing of these five patients in the first efficacy cohort receiving 10 million cells represents a critically important milestone in our AST-OPC1 clinical program for patients with complete cervical spinal cord injuries," said Steve Cartt, President and Chief Executive Officer. "In addition, while it is still very early in the development process and the patient numbers are small, we are encouraged by the upper extremity motor function improvements we have observed so far in patients previously enrolled and dosed in the very low dose two million cell cohort.  Interestingly, this cohort had been designed purely to evaluate safety and was not expected to result in any improved motor function." 

The company noted that this important study milestone paves the way for initiating enrollment of patients in the highest dose 20 million cell cohort and for the recently announced expansion of the study to a broader range of patients with spinal cord injuries. Following independent safety review of the data from the 10 million cell efficacy cohort by the Data Monitoring Committee (DMC), the company expects to begin enrolling and dosing patients in the 20 million cell efficacy cohort in the third quarter of 2016.

"We are now looking forward to initiating enrollment in the high dose 20 million cell efficacy cohort following DMC review of the initial safety data from the current 10 million cell efficacy cohort. In parallel, we will also be expanding enrollment of the study to patients with sensory incomplete injuries, which are less severe than those included in the study so far, under the previously announced FDA-cleared expansion of the ongoing AST-OPC1 study," stated Dr. Edward Wirth III, Chief Medical Officer.  "Enrollment and dosing of this 10 million cell efficacy cohort is also quite significant for Asterias since it paves the way for our very first efficacy readout in January 2017."

In May 2016, Asterias was granted FDA clearance to expand patient enrollment in the Phase 1/2a clinical trial from 13 patients to up to 35 patients, based on the continued favorable safety profile observed in the ongoing clinical study.  The cleared protocol allows for expansion of the two efficacy cohorts in patients with neurologically complete (American Spinal Injury Association Impairment Scale Grade A [AIS-A]) cervical spinal cord injuries to up to eight patients each, as well as the initiation of two additional cohorts of five to eight patients each with motor complete, sensory incomplete (AIS-B) cervical spinal cord injuries. On average, AIS-B patients have slightly more spared spinal cord tissue at the injury site, which the company believes may lead to greater potential for biological response to AST-OPC1.

Additional information on the Phase 1/2a trial, including trial sites, can be found at www.clinicaltrials.gov, using Identifier NCT02302157, and at the SCiStar Study Website (www.scistar-study.com).

About AST-OPC1 and Spinal Cord Injury

AST-OPC1, an oligodendrocyte progenitor population derived from human embryonic stem cells, has been shown in animals or in vitro to have three potentially reparative functions that address the complex pathologies observed at the injury site of a spinal cord injury.  These activities of AST-OPC1 include production of neurotrophic factors, stimulation of vascularization, and induction of remyelination of denuded axons, all of which are critical for the survival and regrowth of axons at the injury site, as well as for the conduction of nerve impulses through those axons. In preclinical animal testing, AST-OPC1 administration led to remyelination of axons, improved hind limb and forelimb locomotor function, dramatic reductions in injury-related cavitation, and significant preservation of myelinated axons traversing the injury site.

There are an estimated 12,500 spinal cord injuries in the US annually.  These injuries can be devastating and carry not only an immense burden for the patients and their families, but also to the overall health care system.  It has been estimated that the cost of lifetime medical care for an individual suffering a spinal cord injury can reach $5 million or more.  There are currently no approved treatments for spinal cord injuries and this remains an area of medicine with extremely high unmet need.

About Asterias Biotherapeutics

Asterias Biotherapeutics, Inc. is a leading biotechnology company in the emerging field of regenerative medicine. The company's proprietary cell therapy programs are based on its immunotherapy and pluripotent stem cell platform technologies. Asterias is presently focused on advancing three clinical-stage programs which have the potential to address areas of very high unmet medical need in the fields of oncology and neurology. AST-OPC1 (oligodendrocyte progenitor cells) is currently in a Phase 1/2a dose escalation clinical trial in spinal cord injury.  AST-VAC1 (antigen-presenting autologous dendritic cells) demonstrated promise in a Phase 2 study in acute myelogenous leukemia (AML) and completed a successful end-of-Phase 2 meeting with the FDA in advance of assessing plans for a single pivotal Phase 3 AML study. AST-VAC2 (antigen-presenting allogeneic dendritic cells) represents a second generation, allogeneic immunotherapy. The company's research partner, Cancer Research UK, plans to begin a Phase 1/2 clinical trial of AST-VAC2 in non-small cell lung cancer in 2017. Additional information about Asterias can be found at www.asteriasbiotherapeutics.com.

FORWARD-LOOKING STATEMENTS

Statements pertaining to future financial and/or operating and/or clinical research results, future growth in research, technology, clinical development, and potential opportunities for Asterias, along with other statements about the future expectations, beliefs, goals, plans, or prospects expressed by management constitute forward-looking statements. Any statements that are not historical fact (including, but not limited to statements that contain words such as "will," "believes," "plans," "anticipates," "expects," "estimates") should also be considered to be forward-looking statements. Forward-looking statements involve risks and uncertainties, including, without limitation, risks inherent in the development and/or commercialization of potential products, uncertainty in the results of clinical trials or regulatory approvals, need and ability to obtain future capital, and maintenance of intellectual property rights. Actual results may differ materially from the results anticipated in these forward-looking statements and as such should be evaluated together with the many uncertainties that affect the businesses of Asterias, particularly those mentioned in the cautionary statements found in Asterias' filings with the Securities and Exchange Commission. Asterias disclaims any intent or obligation to update these forward-looking statements.

SOURCE Asterias Biotherapeutics, Inc.