BACKGROUND: Based on 6-month data from the InVivo Study of Probable Benefit of the Neuro-Spinal Scaffold for Safety and Neurological Recovery in Patients with Complete Thoracic Spinal Cord Injury (INSPIRE) study (NCT02138110), acute implantation of an investigational bioresorbable polymer device (Neuro-Spinal Scaffold [NSS]) appeared to be safe in patients with complete thoracic spinal cord injury (SCI) and was associated with an ASIA Impairment Scale (AIS) conversion rate that exceeded historical controls. OBJECTIVE: To evaluate outcomes through 24 months postimplantation. METHODS: INSPIRE was a prospective, open-label, multicenter, single-arm study. Eligible patients had traumatic nonpenetrating SCI with a visible contusion on MRI, AIS A classification, neurological level of injury at T2-T12, and requirement for open spine surgery ≤96 hours postinjury. RESULTS: Nineteen patients underwent NSS implantation. Three patients had early death determined by investigators to be unrelated to the NSS or its implantation procedure. Seven of 16 evaluable patients (44%) had improvement of ≥1 AIS grade at 6 months (primary end point) to AIS B (n = 5) or AIS C (n = 2). Three patients with AIS B at 6 months had further neurological improvement to AIS C by 12 (n = 2) and 24 (n = 1) months, respectively; none have deteriorated per latest available follow-up. No unanticipated or serious adverse device effects were reported. CONCLUSION In this small group of patients with complete thoracic SCI, acute NSS implantation within the spinal cord appeared to be safe with no long-term neurological issues identified during the 24-month follow-up. Patients remain stable, with additional AIS conversions observed in some patients at 12 months and beyond. These data further support the safety and probable benefit of NSS implantation in this patient population.

INTRODUCTION The Neuro-Spinal Scaffold"! (NSS) is an investigational biodegradable device developed to facilitate spinal cord repair following intraparenchymal implantation within the injured spinal cord. An open-label, single-arm, multicenter clinical study was conducted to evaluate the safety and efficacy of the device in acute thoracic complete spinal cord injury (SCI). Here, we report on available 24-mo follow-up data. METHODS The INSPIRE Study (NCT02138110) enrolled patients with nonpenetrating, thoracic (T2-T12/L1) AIS A SCI within 96 h of injury. Safety and neurological outcomes were assessed. The primary endpoint was AIS conversion rate at 6 mo. The study included an Objective Performance Criterion (OPC) defined as at least 25% of patients demonstrating an AIS grade improvement at 6 mo, which was derived from a 16% natural history AIS conversion rate in the studied patient population.[1] RESULTS A total of 19 patients were implanted with the NSS. There were 3 deaths determined by investigators to be unrelated to the NSS or its implantation. A total of 8 patients have completed the 24-mo assessment visit, with additional follow-up ongoing. Seven of the sixteen patients who reached the 6-mo primary endpoint visit experienced an AIS grade improvement (43.8%; AIS B, n = 5; AIS C, n = 2). Three of the five patients who converted to AIS B experienced further improvement to AIS C at 12 (n = 2) and 24 mo (n = 1) postinjury. At last follow-up, none of the patients with AIS conversion had deteriorated and there were no unanticipated or serious adverse device effects related to the NSS or its implantation as determined by investigators. CONCLUSION The INSPIRE study is the first to clinically evaluate implantation of a scaffold as a treatment for acute SCI. This study describes the safety of the NSS and feasibility of implantation. The AIS conversion rate exceeds published natural history rates and the OPC. Available results at twenty-four months continue to support further clinical investigation.