Asterias Provides Six Month Data Readout for its AST-OPC1 Phase 1/2a Clinical Trial in Severe Spinal Cord Injury

- Current Readout Includes New Six Month Data for Cohort 5 and Aggregate Trial Data -

- Results Continue to Demonstrate Favorable Safety Profile, Potential for Durable Cell Engraftment at the Injury Site and Improved Motor Function -

- 12 Month Top-Line Readout from the Entire SCiStar Study Expected in First Quarter of 2019 -

FREMONT, Calif., July 17, 2018 (GLOBE NEWSWIRE) -- Asterias Biotherapeutics, Inc. (NYSE American:AST), a biotechnology company dedicated to developing cell-based therapeutics to treat neurological conditions associated with demyelination and cellular immunotherapies to treat cancer, today provided additional data from the Company’s ongoing Phase 1/2a SCiStar study designed to evaluate the safety and potential efficacy of AST-OPC1 in the treatment of severe cervical spinal cord injury.   

The SCiStar study is an open-label, single-arm trial testing three escalating doses of AST-OPC1 in 25 subjects with subacute motor complete (AIS-A or AIS-B) cervical (C-4 to C-7) spinal cord injury. These individuals have lost essentially all movement below their injury site and experience severe paralysis of the upper and lower limbs. The SCiStar study consists of five cohorts:

Each subject in the SCiStar study has now completed a six month follow-up and the updated results for the SCiStar study have shown the following:

• Positive Safety Profile - Asterias has dosed 25 subjects with AST-OPC1 in the SCiStar study and a total of 30 subjects including the five subjects from a previous Phase 1 safety trial in thoracic spinal cord injury who have been followed for as long as seven years.  To date, there have been no serious adverse events (SAEs) related to the AST-OPC1 cells.
• Cell Engraftment - 100% (4/4) of Cohort 5 subjects have magnetic resonance imaging (MRI) scans at six months consistent with the formation of a tissue matrix at the injury site, which is encouraging evidence that AST-OPC1 cells have engrafted at the injury site and helped to prevent cavitation.  Together with the previously reported results from Cohorts 2-4, the MRI results-to-date for 95% (21/22) of the Cohort 2-5 subjects provide supportive evidence that AST-OPC1 cells have durably engrafted at the injury site and helped to prevent cavitation.  Cavitation is a destructive process that occurs within the spinal cord following spinal cord injuries, and typically results in permanent loss of motor and sensory function. Additionally, a patient with cavitation can develop a condition known as syringomyelia, which results in additional neurological and functional damage to the patient and can result in chronic pain.
• Improved Motor Function - 100% (4/4) of Cohort 5 subjects have recovered at least one motor level on at least one side through six months, with two subjects having recovered one motor level bilaterally.  At six months, 86% (19/22) of Cohort 2-5 subjects recovered at least one motor level on at least one side and 18% (4/22) of these subjects recovered two or more motor levels on at least one side.  More detailed information on improved motor function is provided in table format further below.

“The results from the SCiStar study remain encouraging as the six-month follow-up data continued to demonstrate a positive safety profile and show that the AST-OPC1 cells are successfully engrafting in patients,” stated Ed Wirth, Chief Medical Officer.  “We are pleased that 19 of the 22 subjects dosed in Cohorts 2 through 5 have recovered at least one motor level on at least one side through six months of follow-up and four of these subjects have recovered two motor levels during this same period.  We expect to release the top-line 12-month data for the study in the first quarter of 2019 and are actively evaluating the design of a randomized controlled study for OPC1.”

“The results are in-line with the data we reported earlier in the year for cohorts 3 and 4 and the overall body of evidence to date supports the primary safety objective for the study,” commented Michael Mulroy, Chief Executive Officer.  “There remain no serious or unexpected adverse events related to OPC1 and we believe the durable engraftment of the OPC1 cells, as evidenced in the earlier results as well, is an important prerequisite to seeing sustained clinical benefits.  We expect to report the 12 month data on cohorts 3 and 4 later this quarter and the full trial results in early 2019 and begin to have more formalized discussions with FDA in the fourth quarter of 2018 on the next clinical study design for OPC1.  We are also in early discussions with the California Institute for Regenerative Medicine (CIRM) regarding a possible grant to partially fund the next clinical study.”

AST-OPC1 Therapeutic Platform

AST-OPC1, an oligodendrocyte progenitor cell population derived from human embryonic stem cells, has been shown in preclinical testing in animals and in vitro to have three potentially reparative functions that address the complex pathologies observed in demyelination disorders, such as spinal cord injuries, and multiple neurodegenerative diseases, including multiple sclerosis and white matter stroke. These potential reparative functions of AST-OPC1 include the production of neurotrophic factors, the stimulation of vascularization, and the induction of remyelination of denuded axons, all of which are critical for survival and regrowth of—and conduction of nerve impulses through—axons at the injury site.   

Each year in the United States, more than 17,000 people suffer a severe, debilitating spinal cord injury. As of 2016, the National Spinal Cord Injury Statistical Center reported that approximately 4,500 of these new spinal cord injuries annually in the U.S. are AIS-A, AIS-B, or AIS-C patients with C-4 to C-7 spinal cord injuries (https://www.nscisc.uab.edu/). These injuries can be devastating to quality of life and ability to function independently. Lifetime healthcare costs for these patients can often approach $5 million. Improvements in arm, hand, and finger functional capabilities in these patients can result in meaningfully lower healthcare costs, significant improvements in quality of life, greater ability to engage in activities of daily living, and increased independence. 

Updated clinical data from the SCiStar study is set forth in the tables below:

Safety 

Asterias has dosed 25 subjects with AST-OPC1 in the SCiStar study and a total of 30 subjects including the five subjects from the previous Phase 1 safety trial.  The results-to-date, which include subjects from the Phase 1 safety trial who have been followed for as long as seven years, continue to support the safety of AST-OPC1.  In particular, there have been no serious, unexpected, adverse events related to AST-OPC1, the injection procedure, or the drug used for immunosuppression in any of the 30 subjects.  Additionally, long-term follow up in the Phase 1 safety trial with annual MRI scans through five years post-injection of AST-OPC1 has shown no evidence of adverse changes in any of the subjects treated with AST-OPC1.

Magnetic Resonance Imaging (MRI) Data

The MRI results-to-date for 95% (21/22) of the subjects in Cohorts 2-5 are consistent with formation of a tissue matrix at the injury site, which is supportive evidence showing that AST-OPC1 cells have durably engrafted at the injury site and helped to prevent cavitation.    Published data indicates that about 50% of all subjects with spinal cord injuries develop an injury cavity within six months following the spinal cord injury.  Meanwhile, for subjects with the severe contusive spinal cord injuries that would meet the criteria for inclusion in the SCiStar study, the percentage of subjects that typically develop an injury cavity would be closer to 80%. 

Upper Extremity Motor Recovery

Improvements in upper extremity motor function are being measured using the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) scale, widely used to quantify functional status of patients with spinal cord injuries. Both patients and physicians consistently report that improvements in upper extremity motor function are the most desirable functional improvement target in the quadriplegic population, since even relatively modest changes can potentially have a significant impact on functional independence, quality of life and cost of care. The SCiStar study is monitoring two separate ISNCSCI measurements of upper extremity motor function. The upper extremity motor score (UEMS), is a scale used to quantify motor function at each of five upper extremity muscle groups driving arm and hand function; these scores are also used to determine "motor levels," which define the level within the cord above which a subject has normal function.  As suggested by existing research, patients with severe spinal cord injuries that show two motor levels of improvement on at least one side may regain the ability to perform daily activities such as feeding, dressing and bathing, which significantly reduces the overall level of daily assistance needed for the patient and associated healthcare costs.

One-Motor Level Recovery

Two-Motor Level Recovery

Upper Extremity Motor Score

Anticipated 2018-19 Data Readouts for the SCiStar Study

Asterias has completed enrollment and dosing in all five of its planned SCiStar study cohorts.   The company intends to report the following data readouts later this year or early in 2019:

• 12 month update for Cohorts 3 and 4 in the third quarter of 2018.
• 24 month update for Cohort 2 in the third or fourth quarter of 2018.
• 12 month update for the entire SCiStar study, including Cohort 5, in the first quarter of 2019.

The Company will provide an overview of the results on its second quarter 2018 operating results conference call, scheduled for August 9, 2018.

About Asterias Biotherapeutics

Asterias Biotherapeutics, Inc. is a biotechnology company dedicated to developing cell-based therapeutics to treat neurological conditions associated with demyelination and cellular immunotherapies to treat cancer. 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 neurology and oncology. AST-OPC1 (oligodendrocyte progenitor cells) is currently in a Phase 1/2a dose escalation clinical trial in spinal cord injury. AST-VAC2 (antigen-presenting allogeneic dendritic cells) is an allogeneic cancer immunotherapy. The company's research partner, Cancer Research UK, has commenced a first-in-human clinical trial of AST-VAC2 in non-small cell lung cancer. AST-VAC1 (antigen-presenting autologous dendritic cells) is an autologous cancer immunotherapy with promising efficacy and safety data from an earlier Phase 2 study in Acute Myeloid Leukemia (AML).  Asterias is also sponsoring pre-clinical work in two conditions with a demyelinating component: Multiple Sclerosis and White Matter Stroke, and is evaluating other cancer indications where its immunotherapy platform could provide therapeutic benefit. Additional information about Asterias can be found at www.asteriasbiotherapeutics.com.

About AST-OPC1

AST-OPC1, an oligodendrocyte progenitor cell population derived from human embryonic stem cells, has been shown in preclinical testing in animals and in vitro to have three potentially reparative functions that address the complex pathologies observed in demyelination disorders, such as spinal cord injuries, and multiple neurodegenerative diseases, including multiple sclerosis and white matter stroke. These potential reparative functions of AST-OPC1 include the production of neurotrophic factors, the stimulation of vascularization, and the induction of remyelination of denuded axons, all of which are critical for survival and regrowth of—and conduction of nerve impulses through—axons at the injury site.   

About the SCiStar Trial

The SCiStar trial is an open-label, single-arm trial testing three sequential escalating doses of AST-OPC1 administered at up to 20 million AST-OPC1 cells in 25 subjects with subacute motor complete (AIS-A or AIS-B) cervical (C-4 to C-7) SCI. These individuals have essentially lost all movement below their injury site and experience severe paralysis of the upper and lower limbs. AIS-A subjects have lost all motor and sensory function below their injury site, while AIS-B subjects have lost all motor function but may have retained some minimal sensory function below their injury site. AST-OPC1 is administered 21 to 42 days post-injury. Subjects will be followed by neurological exams and imaging procedures to assess the safety and activity of the product.

Each year in the United States, more than 17,000 people suffer a severe, debilitating spinal cord injury. As of 2016, the National Spinal Cord Injury Statistical Center reported that approximately 4,500 of these new spinal cord injuries annually in the U.S. are AIS-A, AIS-B, or AIS-C patients with C-4 to C-7 spinal cord injuries (https://www.nscisc.uab.edu/). These injuries can be devastating to quality of life and ability to function independently. Lifetime healthcare costs for these patients can often approach $5 million. Improvements in arm, hand, and finger functional capabilities in these patients can result in meaningfully lower healthcare costs, significant improvements in quality of life, greater ability to engage in activities of daily living, and increased independence.

Asterias has received a Strategic Partnerships Award grant from the California Institute for Regenerative Medicine, which provided $14.3 million of non-dilutive funding for the Phase 1/2a clinical trial and other product development activities for 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).

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," or “possible”) 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.

Contacts:
Investor Relations
(510) 456-3892
InvestorRelations@asteriasbio.com
or
EVC Group, Inc.
Michael Polyviou/Todd Kehrli
(732) 232-6914
mpolyviou@evcgroup.com; tkehrli@evcgroup.com