Clinical Trials In Spinal Cord Injury Research Articles

Clinical trials for neuroregenerative therapies for spinal cord injury: what have we learnt so far?

ABSTRACT Introduction There remains a lack of effective regenerative therapies to treat traumatic spinal cord injury (SCI). On a global level, patients living with SCI, their families, and the healthcare system are impacted by the extensive financial burden associated with the management of SCI. Clinical trials are crucial to assess the real-world efficacy of the different emerging neuroregenerative approaches that have shown promise in the pre-clinical stages of research. Areas covered This perspective summarizes and discusses potential solutions to several key challenges that clinical investigators evaluating novel therapeutic strategies to treat SCI might face: 1) the challenges in patient recruitment and meeting enrollment targets with adequate statistical power; 2) the loss of patients to follow-up; 3) the heterogeneity in patient presentation and recovery trajectories; 4) the complex multifaceted pathophysiology of SCI that renders investigations of single therapeutic approaches difficult; 5) the challenge of capturing positive treatment effects of investigative therapies; 6) the high costs associated with conducting clinical trials; 7) the implementation of current guidelines for treating SCI to optimize care delivery and clinical trial conduct; 8) the shift in SCI patient demographics reflective of an aging population; and 9) navigating regulatory bodies to translate therapies into the clinic. Expert opinion There are challenges when conducting SCI clinical trials that span broadly across medical, social, political, and economic considerations. Thus, we should employ an interdisciplinary approach when addressing these challenges in order to facilitate the evaluation of novel treatments for SCI.

Current Concepts of Biomaterial Scaffolds and Regenerative Therapy for Spinal Cord Injury.

Spinal cord injury (SCI) is a catastrophic condition associated with significant neurological deficit and social and financial burdens. It is currently being managed symptomatically, with no real therapeutic strategies available. In recent years, a number of innovative regenerative strategies have emerged and have been continuously investigated in preclinical research and clinical trials. In the near future, several more are expected to come down the translational pipeline. Among ongoing and completed trials are those reporting the use of biomaterial scaffolds. The advancements in biomaterial technology, combined with stem cell therapy or other regenerative therapy, can now accelerate the progress of promising novel therapeutic strategies from bench to bedside. Various types of approaches to regeneration therapy for SCI have been combined with the use of supportive biomaterial scaffolds as a drug and cell delivery system to facilitate favorable cell-material interactions and the supportive effect of neuroprotection. In this review, we summarize some of the most recent insights of preclinical and clinical studies using biomaterial scaffolds in regenerative therapy for SCI and summarized the biomaterial strategies for treatment with simplified results data. One hundred and sixty-eight articles were selected in the present review, in which we focused on biomaterial scaffolds. We conducted our search of articles using PubMed and Medline, a medical database. We used a combination of "Spinal cord injury" and ["Biomaterial", or "Scaffold"] as search terms and searched articles published up until 30 April 2022. Successful future therapies will require these biomaterial scaffolds and other synergistic approaches to address the persistent barriers to regeneration, including glial scarring, the loss of a structural framework, and biocompatibility. This database could serve as a benchmark to progress in future clinical trials for SCI using biomaterial scaffolds.

The Emerging Role of Biological Sex in Cell Therapy for Spinal Cord Injury.

Neural progenitor cell (NPC) transplantation is a promising potential therapy for replacing spinal cord neurons and glial cells following spinal cord injury (SCI). Despite the rapid advancement of NPC transplantation to SCI clinical trials, we still lack understanding of fundamental biology underlying how NPC grafts interact with the injured host nervous system. Our recent study demonstrated a potent effect of biological sex mismatch between donor and host on graft immune rejection. Here we discuss the implications of this study in the context of clinical trials for SCI, and important topics for future research in SCI cell transplantation.

Improving translatability of spinal cord injury research by including age as a demographic variable.

Pre-clinical and clinical spinal cord injury (SCI) studies differ in study design, particularly in the demographic characteristics of the chosen population. In clinical study design, criteria such as such as motor scores, neurological level, and severity of injury are often key determinants for participant inclusion. Further, demographic variables in clinical trials often include individuals from a wide age range and typically include both sexes, albeit historically most cases of SCI occur in males. In contrast, pre-clinical SCI models predominately utilize young adult rodents and typically use only females. While it is often not feasible to power SCI clinical trials to test multi-variable designs such as contrasting different ages, recent pre-clinical findings in SCI animal models have emphasized the importance of considering age as a biological variable prior to human experiments. Emerging pre-clinical data have identified case examples of treatments that diverge in efficacy across different demographic variables and have elucidated several age-dependent effects in SCI. The extent to which these differing or diverging treatment responses manifest clinically can not only complicate statistical findings and trial interpretations but also may be predictive of worse outcomes in select clinical populations. This review highlights recent literature including age as a biological variable in pre-clinical studies and articulates the results with respect to implications for clinical trials. Based on emerging unpredictable treatment outcomes in older rodents, we argue for the importance of including age as a biological variable in pre-clinical animal models prior to clinical testing. We believe that careful analyses of how age interacts with SCI treatments and pathophysiology will help guide clinical trial design and may improve both the safety and outcomes of such important efforts.

Effects of biological sex mismatch on neural progenitor cell transplantation for spinal cord injury in mice

Despite advancement of neural progenitor cell transplantation to spinal cord injury clinical trials, there remains a lack of understanding of how biological sex of transplanted cells influences outcomes after transplantation. To address this, we transplanted GFP-expressing sex-matched, sex-mismatched, or mixed donor cells into sites of spinal cord injury in adult male and female mice. Biological sex of the donor cells does not influence graft neuron density, glial differentiation, formation of the reactive glial cell border, or graft axon outgrowth. However, male grafts in female hosts feature extensive hypervascularization accompanied by increased vascular diameter and perivascular cell density. We show greater T-cell infiltration within male-to-female grafts than other graft types. Together, these findings indicate a biological sex-specific immune response of female mice to male donor cells. Our work suggests that biological sex should be considered in the design of future clinical trials for cell transplantation in human injury.

190. Predictions for who are lost to follow-up in spinal cord injury clinical trials: an opportunity to enhance trial design and execution

<h3>BACKGROUND CONTEXT</h3> Despite advancements in research and promising preclinical findings we have yet to isolate any new practice-changing interventions for the treatment of spinal cord injury (SCI) in clinical trials. This raises concerns about the methodology and design of clinical trials in SCI. One of the concerns in SCI trials is with high rates of missing data. Combined with difficulty in recruiting patients and the cost associated with clinical trials in SCI strategies need to be implemented to reduce the rates of loss to follow-up (LTFU) in trials <h3>PURPOSE</h3> Identify factors associated with LTFU in SCI clinical trials. <h3>STUDY DESIGN/SETTING</h3> Multicenter, prospective data from the STASCIS study and the NACTN registry database were analyzed for this study. <h3>PATIENT SAMPLE</h3> All adult patients with SCI from the STASCIS and NACTN registries were selected. <h3>OUTCOME MEASURES</h3> LTFU was defined to be in patients whodid not come to follow up at 12 months and previously did not come to follow-up at least 3 months after baseline ASIA Impairment Scale assessment (≤72 hours post-injury). <h3>METHODS</h3> Missing data were imputed with multiple imputations. Univariate analysis was performed for each independent variable, and predictors with p < 0.2 were included in the final multivariate model for backward stepwise logistic regression based on AIC values. Odds ratios with 95% confidence intervals were calculated with a significance level set as p < 0.05. <h3>RESULTS</h3> A total of 885 patients (46.5±17.6, 45.5% female) were eligible for inclusion. On univariate analysis, 23 variables were significant and included for feature selection. In the final model, patients were less likely to miss follow-up if they had higher baseline lower extremity motor scores (OR: 0.99[0.98-0.99], p=0.021), received early surgery (OR: 0.49[0.35-0.69], p < 0.001), Asian (OR: 0.31[0.18-0.54], p < 0.001) or Black race (OR: 0.63[95% CI 0.45-0.88], p=0.006) compared to White Caucasian, or had a systemic infection complication (OR: 0.35[0.17-0.70], p=0.003). Independent predictors of LTFU were postoperative DVT (OR: 3.28[1.64-6.55], p=0.001) and hematological complications (OR: 1.67[1.07-2.60], p=0.025), and a history of malignancy (OR: 3.65[1.01-13.15], p=0.048) and smoking (OR: 1.55[1.15-2.08], p=0.004). Higher baseline GCS was associated with making follow-up (OR: 0.94[0.88-1.00], p=0.053) and diabetic history with LTFU (OR: 1.56[0.97-2.52], p=0.068), but were not statistically significant in the final model. <h3>CONCLUSIONS</h3> Patients that had a greater motor disability, late surgery and associated comorbidities (such as the history of malignancy, smoking, DVT and hematological complications), are at greater risk for LTFU and may require concerted patient engagement approaches to ensure comprehensive spinal care and track recovery trajectory. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Reply: Poor statistical reporting in a spinal cord injury clinical trial

Reply: Poor statistical reporting in a spinal cord injury clinical trial

Inclusive Trial Designs in Acute Spinal Cord Injuries: Prediction–Based Stratification of Clinical Walking Outcome and Projected Enrolment Frequencies

Background New therapeutic approaches in neurological disorders are progressing into clinical development. Past failures in translational research have underlined the critical importance of selecting appropriate inclusion criteria and primary outcomes. Narrow inclusion criteria provide sensitivity, but increase trial duration and cost to the point of infeasibility, while broader requirements amplify confounding, increasing the risk of trial failure. This dilemma is perhaps most pronounced in spinal cord injury (SCI), but applies to all neurological disorders with low frequency and/or heterogeneous clinical manifestations. Objective Stratification of homogeneous patient cohorts to enable the design of clinical trials with broad inclusion criteria. Methods Prospectively–gathered data from patients with acute cervical SCI were analysed using an unbiased recursive partitioning conditional inference tree (URP–CTREE) approach. Performance in the 6-minute walk test at 6 months after injury was classified based on standardized neurological assessments within the first 15 days of injury. Functional and neurological outcomes were tracked throughout rehabilitation up to 6 months after injury. Results URP–CTREE identified homogeneous outcome cohorts in a study group of 309 SCI patients. These cohorts were validated by an internal, yet independent, validation group of 172 patients. The study group cohorts identified demonstrated distinct recovery profiles throughout rehabilitation. The baseline characteristics of the analysed groups were compared to a reference group of 477 patients. Conclusion URP–CTREE enables inclusive trial design by revealing the distribution of outcome cohorts, discerning distinct recovery profiles and projecting potential patient enrolment by providing estimates of the relative frequencies of cohorts to improve the design of clinical trials in SCI and beyond.

Dynamics of biomarkers across the stages of traumatic spinal cord injury - implications for neural plasticity and repair.

Traumatic spinal cord injury (SCI) is a complex medical condition causing significant physical disability and psychological distress. While the adult spinal cord is characterized by poor regenerative potential, some recovery of neurological function is still possible through activation of neural plasticity mechanisms. We still have limited knowledge about the activation of these mechanisms in the different stages after human SCI. In this review, we discuss the potential role of biomarkers of SCI as indicators of the plasticity mechanisms at work during the different phases of SCI. An extensive review of literature related to SCI pathophysiology, neural plasticity and humoral biomarkers was conducted by consulting the PubMed database. Research and review articles from SCI animal models and SCI clinical trials published in English until January 2021 were reviewed. The selection of candidates for humoral biomarkers of plasticity after SCI was based on the following criteria: 1) strong evidence supporting involvement in neural plasticity (mandatory); 2) evidence supporting altered expression after SCI (optional). Based on selected findings, we identified two main groups of potential humoral biomarkers of neural plasticity after SCI: 1) neurotrophic factors including: Brain derived neurotrophic factor (BDNF), Nerve growth factor (NGF), Neurotrofin-3 (NT-3), and Insulin-like growth factor 1 (IGF-1); 2) other factors including: Tumor necrosis factor-alpha (TNF-α), Matrix Metalloproteinases (MMPs), and MicroRNAs (miRNAs). Plasticity changes associated with these biomarkers often can be both adaptive (promoting functional improvement) and maladaptive. This dual role seems to be influenced by their concentrations and time-window during SCI. Further studies of dynamics of biomarkers across the stages of SCI are necessary to elucidate the way in which they reflect the remodeling of neural pathways. A better knowledge about the mechanisms underlying plasticity could guide the selection of more appropriate therapeutic strategies to enhance positive spinal network reorganization.

Time-to-enrollment in clinical trials investigating neurological recovery in chronic spinal cord injury: observations from a systematic review and ClinicalTrials.gov database

Currently, large numbers of clinical trials are performed to investigate different forms of experimental therapy for patients suffering from chronic spinal cord injury (SCI). However, for the enrollment process, there are different views on how the time period between injury and interventions should be determined. Herein, we sought to evaluate the impact of time-to-enrollment in chronic SCI clinical trials. A data set comprising 957 clinical studies from clinicalTrials.gov was downloaded and analyzed focusing on the eligibility criteria for post-injury time-to-enrollment. We also aggregated individual patient data from nine clinical trials of regenerative interventions for chronic SCI selected by a systematic literature search from 1990 to 2018. Characteristics of the studies were assessed and compared by dividing into three groups based on time-to-enrollment (group 1 ≤ 12 months, group 2 = 12–23 months and group 3 ≥ 24 months). In ClinicalTrials.gov registry, 445 trials were identified for chronic SCI where 87% (385) were unrestricted in the maximum post-injury time for trial eligibility. From systematic literature search, nine studies and 156 patients (group 1 = 30, group 2 = 55 and group 3 = 71) were included. The range of time-to-enrollment was 0.5 to 321 months in those studies. We also observed various degrees of motor and sensory improvement in between three time-to-enrollment groups. Our results indicate that enrolling wide ranges of time-to-enrollment in a group may present imprecise outcomes. Clinical trial designs should consider appropriate post-injury time frames to evaluate therapeutic benefit.

Spinal Cord Injury-Movement Index (SCI-MI) Fine Motor Scale: Development and Preliminary Validation

Abstract Date Presented 04/21/21 Most spinal cord injury (SCI) clinical trial measures do not have the capability to accurately measure recovery of movement, which creates serious problems for SCI clinical trials that have motor recovery or repair as an endpoint. Work is underway to develop a clinical trial outcome measure that is intended to evaluate recovery of neurotypical movement within the context of function. This poster presents the iterative development process of the fine motor item pool for this outcome measure. Primary Author and Speaker: Rachel Kim Additional Authors and Speakers: William Conrad, Dianna Lunsford, Kristin Valdes

Spinal Cord Repair: From Cells and Tissue Engineering to Extracellular Vesicles.

Spinal cord injury (SCI) is a debilitating condition, often leading to severe motor, sensory, or autonomic nervous dysfunction. As the holy grail of regenerative medicine, promoting spinal cord tissue regeneration and functional recovery are the fundamental goals. Yet, effective regeneration of injured spinal cord tissues and promotion of functional recovery remain unmet clinical challenges, largely due to the complex pathophysiology of the condition. The transplantation of various cells, either alone or in combination with three-dimensional matrices, has been intensively investigated in preclinical SCI models and clinical trials, holding translational promise. More recently, a new paradigm shift has emerged from cell therapy towards extracellular vesicles as an exciting “cell-free” therapeutic modality. The current review recapitulates recent advances, challenges, and future perspectives of cell-based spinal cord tissue engineering and regeneration strategies.

A Systematic Review of Safety Reporting in Acute Spinal Cord Injury Clinical Trials: Challenges and Recommendations.

Accurate safety information in published clinical trials guides the assessment of risk-benefit, as well as the design of future clinical trials. Comprehensive reporting of adverse events, toxicity, and discontinuations from acute spinal cord injury clinical trials is an essential step in this process. Here, we sought to assess the degree of "satisfactoriness" of reporting in past clinical trials in spinal cord injury. A review of citations from MEDLINE and EMBASE identified eligible clinical trials in acute (within 30 days) spinal cord injury. English language studies, published between 1980 and 2020, with sensory, motor, or autonomic neurological assessments as the primary outcome measure were eligible for inclusion. Criteria were then established to qualify the safety reporting as satisfactory (i.e., distinguished severe/life-threatening events), partially satisfactory, or unsatisfactory (i.e., only mentioned in general statements, or reported but without distinguishing severe events). A total of 40 trials were included. Satisfactory reporting for clinical adverse events was observed in 30% of trials; partially satisfactory was achieved by 10% of the trials, and the remaining 60% were unsatisfactory. The majority of trials were determined to be unsatisfactory for the reporting of laboratory-defined toxicity (82.5%); only 17.5% were satisfactory. Discontinuations were satisfactorily reported for the majority of trials (80%), with the remaining partially satisfactory (5%) or unsatisfactory (15%). Reporting of safety in clinical trials for acute spinal cord injury is suboptimal. Due to the complexities of acute spinal cord injury (e.g., polytrauma, multiple systems affected), tailored and specific standards for tracking adverse events and safety reporting should be established.

Trajectory-Based Classification of Recovery in Sensorimotor Complete Traumatic Cervical Spinal Cord Injury.

To test the hypothesis that sensorimotor complete traumatic cervical spinal cord injury (SCI) is a heterogenous clinical entity comprising several subpopulations that follow fundamentally different trajectories of neurologic recovery. We analyzed demographic and injury data from 655 patients who were pooled from 4 prospective longitudinal multicenter studies. Group-based trajectory modeling was applied to model neurologic recovery trajectories over the initial 12 months postinjury and to identify predictors of recovery trajectories. Neurologic outcomes included upper extremity motor score, total motor scores, and American Spinal Injury Association Impairment Scale (AIS) grade improvement. The analysis identified 3 distinct trajectories of neurologic recovery. These clinical courses included (1) marginal recovery trajectory, characterized by minimal or no improvement in motor strength or change in AIS grade status (remained grade A); (2) moderate recovery trajectory, characterized by low baseline motor scores that improved approximately 13 points or AIS conversion of 1 grade point; (3) good recovery trajectory, characterized by baseline motor scores in the upper quartile that improved to near maximum values within 3 months of injury. Patients following the moderate or good recovery trajectories were younger, had more caudally located injuries, had a higher degree of preserved motor and sensory function at baseline examination, and exhibited a greater extent of motor and sensory function in the zone of partial preservation. Cervical complete SCI can be classified into one of 3 distinct subpopulations with fundamentally different trajectories of neurologic recovery. This study defines unique clinical phenotypes based on potential for recovery, rather than baseline severity of injury alone. This approach may prove beneficial in clinical prognostication and in the design and interpretation of clinical trials in SCI.

Neurophysiological Changes in the First Year After Cell Transplantation in Sub-acute Complete Paraplegia.

Neurophysiological testing can provide quantitative information about motor, sensory, and autonomic system connectivity following spinal cord injury (SCI). The clinical examination may be insufficiently sensitive and specific to reveal evolving changes in neural circuits after severe injury. Neurophysiologic data may provide otherwise imperceptible circuit information that has rarely been acquired in biologics clinical trials in SCI. We reported a Phase 1 study of autologous purified Schwann cell suspension transplantation into the injury epicenter of participants with complete subacute thoracic SCI, observing no clinical improvements. Here, we report longitudinal electrophysiological assessments conducted during the trial. Six participants underwent neurophysiology screening pre-transplantation with three post-transplantation neurophysiological assessments, focused on the thoracoabdominal region and lower limbs, including MEPs, SSEPs, voluntarily triggered EMG, and changes in GSR. We found several notable signals not detectable by clinical exam. In all six participants, thoracoabdominal motor connectivity was detected below the clinically assigned neurological level defined by sensory preservation. Additionally, small voluntary activations of leg and foot muscles or positive lower extremity MEPs were detected in all participants. Voluntary EMG was most sensitive to detect leg motor function. The recorded MEP amplitudes and latencies indicated a more caudal thoracic level above which amplitude recovery over time was observed. In contrast, further below, amplitudes showed less improvement, and latencies were increased. Intercostal spasms observed with EMG may also indicate this thoracic “motor level.” Galvanic skin testing revealed autonomic dysfunction in the hands above the injury levels. As an open-label study, we can establish no clear link between these observations and cell transplantation. This neurophysiological characterization may be of value to detect therapeutic effects in future controlled studies.

Adaptive trial designs for spinal cord injury clinical trials directed to the central nervous system.

Narrative review. To provide an overview of adaptive trial designs, and describe how adaptive methods can address persistent challenges encountered by randomized controlled trials of people with spinal cord injury (SCI). With few exceptions, adaptive methodologies have not been incorporated into clinical trial designs of people with SCI. Adaptive methods provide an opportunity to address high study costs, slow recruitment, and excessive amount of time needed to carry out the trial. The availability of existing SCI registries are well poised to support modeling and simulation, both of which are used extensively in adaptive trial designs. Eight initiatives for immediate advancement of adaptive methods in SCI were identified. Although successfully applied in other fields, adaptive clinical trial designs in SCI clinical trial programs have been narrow in scope and few in number. Immediate application of several adaptive methods offers opportunity to improve efficiency of SCI trials. Concerted effort is needed by all stakeholders to advance adaptive clinical trial design methodology in SCI.

The Damaged Spinal Cord Is a Suitable Target for Stem Cell Transplantation

Background. Given individuals with spinal cord injury (SCI) approaching 2 million, viable options for regenerative repair are desperately needed. Human central nervous system stem cells (HuCNS-SC) are self-renewing, multipotent adult stem cells that engraft, migrate, and differentiate in appropriate regions in multiple animal models of injured brain and spinal cord. Preclinical improved SCI locomotor function provided rationale for the first-in-human SCI clinical trial of HuCNS-SC cells. Evidence of feasibility and long-term safety of cell transplantation into damaged human cord is needed to foster translational progression of cellular therapies. Methods. A first-ever, multisite phase I/IIa trial involving surgical transplantation of 20 million HuCNS-SC cells into the thoracic cord in 12 AIS A or B subjects (traumatic, T2-T11 motor-complete, sensory-incomplete), aged 19 to 53 years, demonstrated safety and preliminary efficacy. Six-year follow-up data were collected (sensory thresholds and neuroimaging augmenting clinical assessments). Findings. The study revealed short- and long-term surgical and medical safety (well-tolerated immunosuppression in population susceptible to infections). Preliminary efficacy measures identified 5/12 with reliable sensory improvements. Unfortunately, without thoracic muscles available for manual muscle examination, thoracic motor changes could not be measured. Lower limb motor scores did not change during the study. Cervical cord imaging revealed, no tumor formation or malformation of the lesion area, and secondary supralesional structural changes similar to SCI control subjects. Interpretation. Short- and long-term safety and feasibility support the consideration of cell transplantation for patients with complete and incomplete SCI. This report is an important step to prepare, foster, and maintain the therapeutic development of cell transplantation for human SCI.

Electrophysiological Outcome Measures in Spinal Cord Injury Clinical Trials: A Systematic Review.

Background: Electrophysiological measures are being increasingly utilized due to their ability to provide objective measurements with minimal bias and to detect subtle changes with quantitative data on neural function. Heterogeneous reporting of trial outcomes limits effective interstudy comparison and optimization of treatment. Objective: The objective of this systematic review is to describe the reporting of electrophysiological outcome measures in spinal cord injury (SCI) clinical trials in order to inform a subsequent consensus study. Methods: A systematic search of PubMed and EMBASE databases was conducted according to PRISMA guidelines. Adult human SCI clinical trials published in English between January 1, 2008 and September 15, 2018 with at least one electrophysiological outcome measure were eligible. Findings were reviewed by all authors to create a synthesis narrative describing each outcome measure. Results: Sixty-four SCI clinical trials were included in this review. Identified electrophysiological outcomes included electromyography activity (44%), motor evoked potentials (33%), somatosensory evoked potentials (33%), H-reflex (20%), reflex electromyography activity (11%), nerve conduction studies (9%), silent period (3%), contact heat evoked potentials (2%), and sympathetic skin response (2%). Heterogeneity was present in regard to both methods of measurement and reporting of electrophysiological outcome measures. Conclusion: This review demonstrates need for the development of a standardized reporting set for electrophysiological outcome measures. Limitations of this review include exclusion of non-English publications, studies more than 10 years old, and an inability to assess methodological quality of primary studies due to a lack of guidelines on reporting of systematic reviews of outcome measures.

Application of electrophysiological measures in spinal cord injury clinical trials: a narrative review.

Narrative review. To discuss how electrophysiology may contribute to future clinical trials in spinal cord injury (SCI) in terms of: (1) improvement of SCI diagnosis, patient stratification and determination of exclusion criteria; (2) the assessment of adverse events; and (3) detection of therapeutic effects following an intervention. An international expert panel for electrophysiological measures in SCI searched and discussed the literature focused on the topic. Electrophysiology represents a valid method to detect, track, and quantify readouts of nerve functions including signal conduction, e.g., evoked potentials testing long spinal tracts, and neural processing, e.g., reflex testing. Furthermore, electrophysiological measures can predict functional outcomes and thereby guide rehabilitation programs and therapeutic interventions for clinical studies. Objective and quantitative measures of sensory, motor, and autonomic function based on electrophysiological techniques are promising tools to inform and improve future SCI trials. Complementing clinical outcome measures, electrophysiological recordings can improve the SCI diagnosis and patient stratification, as well as the detection of both beneficial and adverse events. Specifically composed electrophysiological measures can be used to characterize the topography and completeness of SCI and reveal neuronal integrity below the lesion, a prerequisite for the success of any interventional trial. Further validation of electrophysiological tools with regard to their validity, reliability, and sensitivity are needed in order to become routinely applied in clinical SCI trials.

A zebrafish drug screening platform boosts the discovery of novel therapeutics for spinal cord injury in mammals

Spinal cord injury (SCI) is a complex condition, with limited therapeutic options, that results in sensory and motor disabilities. To boost discovery of novel therapeutics, we designed a simple and efficient drug screening platform. This innovative approach allows to determine locomotor rescue properties of small molecules in a zebrafish (Danio rerio) larval spinal cord transection model. We validated our screening platform by showing that Riluzole and Minocycline, two molecules that are in clinical trials for SCI, promote rescue of the locomotor function of the transected larvae. Further validation of the platform was obtained through the blind identification of D-Cycloserine, a molecule scheduled to enter phase IV clinical trials for SCI. Importantly, we identified Tranexamic acid and further showed that this molecule maintains its locomotor recovery properties in a rodent female contusion model. Our screening platform, combined with drug repurposing, promises to propel the rapid translation of novel therapeutics to improve SCI recovery in humans.