Cell therapy for patients with severe spinal cord injury (phase I/IIа): Assessment of safety and primary efficacy of therapy

Background. The problem of pathogenetic treatment of spinal cord injury (SCI) is extremely acute, especially against the background of the growing number of SCI in modern conditions. The world literature widely presents the scientific research on the development and application of regenerative technologies and cell therapy effective for patients with SCI. One of the most promising areas is the use of stem cells. The human umbilical cord blood cells (HUCBCs) is one of the sources for obtaining stem cells having a number of serious advantages such as high efficiency in the patients’ treatment with traumatic lesions of the central nervous system. Aim. To evaluate the safety and primary efficacy of serial systemic (intravenous) administration of allogeneic mononuclear cells of the HUPBC to adult patients with gross neurological deficit because of acute period of severe contusion SCI. Material and methods. Phase I of the SUBSCI I / IIa study included 10 patients (experimental and control groups) with severe SCI (cervical / thoracic / upper lumbar) in the acute period with gross neurological deficit (A / B on the ASIA scale). The conducted treatment included 4 systemic (intravenous) administrations of HUCBCs (allogeneic and compatible by AB0 and Rh factor) within 3 days from the moment of SCI, strictly after the primary surgical intervention. Observation period lasted 12 months after trauma. Safety assessment included the registration of all adverse events (AE) during the observation period with their further classification by severity (CTCAE v. 5.0) and potential connection with the cell therapy. The primary efficacy assessment was the identification of the neurological deficit dynamics (ASIA) – assessment of the restoration degree of motor and sensory functions of the lower extremities during the 1st year. Results and discussion. A total of 419 AEs were detected in 10 patients, but only 2 of them (clinically insignificant) were assessed as probably related to cell therapy, the remaining 417 were not related to therapy. All patients had no signs of immunization to the administered HUCBCs samples. The analysis of the neurological deficit dynamics indicates the reliable restoration of motor functions in patients after cell therapy, compared with the control group. Conclusion. Based on the results obtained, the systemic administration of allogeneic HUPBC, selected without taking into account the HLA system, can be considered as a safe and effective method for treating contusion SCI in the acute period.