A new therapy to treat spinal cord injuries in people who have lost all motor and sensory function below the injury site has shown additional motor function improvement at six-months and nine-months following treatment with 10 million AST-OPC1. The positive efficacy results from an ongoing clinical research study were revealed in a conference held by Asterias Biotherapeutics, the biotechnology company manufacturing AST-OPC1.
AST-OPC1 cells are made from embryonic stem cells by carefully converting them into oligodendrocyte progenitor cells, which are cells found in the brain and spinal cord that support the healthy functioning of nerve cells and can potentially make poorly functioning nerves function better.
“With these patients, we are seeing what we believe are meaningful improvements in their ability to use their arms, hands and fingers at six months and nine months following AST-OPC1 administration,” says Richard G Fessler, professor in the department of neurosurgery at Rush University Medical Center and lead investigator in the SCiStar Phase 1/2a study. Rush is one of six centres in the country currently studying this new approach.
A total of six patients were enrolled and treated with 10 million AST-OPC1 cells, with five of six patients having now completed a six-month follow-up, and three of six patients having completed a nine-month follow-up.
“Recovery of upper extremity motor function is critically important to patients with complete cervical spinal cord injuries, since this can dramatically improve quality of life and their ability to live independently,” says Fessler.
In September 2016, Fessler reported positive early efficacy data for AST-OPC1 from the patients who have lost all motor and sensory function below injury site that had been treated with 10 million AST-OPC1 cells in the study. The interim research results were announced at the 55th annual Scientific Meeting of the International Spinal Cord Society (ISCOS; 4-16 September 2016, Vienna, Austria).
“We look forward to initiating discussions with the FDA in mid-2017 to begin to determine the most appropriate clinical and regulatory path forward for this innovative therapy,” says Steve Cartt, chief executive officer of Asterias.
Improvements in upper extremity motor function are being measured using the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) scale. The latest results include the following highlights:
Improvements in Motor Function
• Upper extremity motor score – For the five patients who have completed at least six months of follow-up, all five patients saw their early improvements in motor score (UEMS) at three months maintained or further increased through their most recent data point (six months or nine months, depending on the most recent data available for each patient).
• Motor level improvement – For patients completing at least six months of follow up, as of the date of each patient’s last follow-up visit, 100% (all five) had achieved at least a one motor level improvement (using the ISNCSCI scale) over baseline on at least one side, and 40% (two of five) had achieved two motor levels over baseline on at least one side, with one of these patients achieving a two motor level improvement on both sides.
• Matched historical control data – Asterias and experts in the spinal cord injury field have developed a set of matched historical control data for both upper extremity motor score and motor level improvement to clearly document expected spontaneous recovery in untreated patients for comparison to results seen in patients treated with AST-OPC1.
• The trial results to date continue to reveal a positive safety profile for AST-OPC1. There have been no serious adverse events related to AST-OPC1 and data from the study indicate that AST-OPC1 can be safely administered to patients in the subacute period after severe cervical spinal cord injury.
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 as many as 35 patients with sub-acute, C5 to C7, motor complete (AIS-A or AIS-B) cervical SCI.
AST-OPC1 is being administered 14 to 30 days post-injury. Patients will be followed by neurological exams and imaging procedures to assess the safety and activity of the product.
The study is being conducted at six centres in the USA, and the company plans to increase this to up to 12 sites to accommodate the expanded patient enrolment. Clinical sites that have enrolled and dosed patients in the study include the Medical College of Wisconsin in Milwaukee, Shepherd Medical Center in Atlanta, University of Southern California (USC) in Los Angeles, Rush University Medical Center in Chicago and Santa Clara Valley Medical Center in San Jose, all USA.
The study is funded by Asterias Biotherapeutics, which developed the AST-OPC1 treatment used in the study, and also in part by a US$14.3 million grant from the California Institute for Regenerative Medicine.