Safety And Efficacy Study Of Intravenous (IV) Administration Of Elezanumab To Assess Change In Upper Extremity Motor Score (UEMS) In Adult Participants With Acute Traumatic Cervical Spinal Cord Injury (SCI)

A Randomized, Double-Blind, Placebo-Controlled Proof of Concept Study to Assess the Safety and Efficacy of Elezanumab in Acute Traumatic Cervical Spinal Cord Injury

Acute Spinal Cord Injury (SCI) is a rare injury that leads to permanent neuromotor impairment and sudden disability. Approximately 25,000 people experience cervical SCI in the United States, Europe, and Japan every year. The purpose of this study is to see if elezanumab is safe and assess change in Upper Extremity Motor Score (UEMS) in participants with acute traumatic cervical SCI.

Elezanumab is an investigational drug being developed for the treatment of SCI. Elezanumab is a monoclonal antibody, that binds to an inhibitor of neuronal regeneration and neutralizes the inhibitor, thus potentially promoting neuroregeneration. This study is "double-blinded", which means that neither trial participants nor the study doctors will know who will be given which study drug. Study doctors put the participants in 1 of 2 groups, called treatment arms. Each group receives a different treatment. There is a 1 in 3 chance that participants will be assigned to placebo. Participants 18-75 years of age with a SCI will be enrolled. Approximately 54 participants will be enrolled in the study in approximately 49 sites worldwide.

Participants will receive intravenous (IV) doses of elezanumab or placebo within 24 hours of injury and every 4 weeks thereafter through Week 48 for a total of 13 doses.

There may be a higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the course of the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, blood tests, checking for side effects and completing questionnaires.

Inclusion Criteria:

• Acute traumatic cervical spinal cord injury (SCI), neurological level of injury of C4, C5, C6, or C7 with no damage to cord in thoracic (T2 and beyond) and lumbar regions that, in the investigator's opinion, would significantly limit recovery.
• Maximum screening UEMS of 32.
• American Spinal Injury Association Impairment Scale (AIS) grade A or B at Screening.
• Able to initiate study drug administration within 24 hours of injury.
• Participants with comorbid conditions that, in the investigator's opinion, are clinically stable and not expected to meaningfully progress in the following 12 months, may be considered eligible to participate.

Exclusion Criteria:

• Evidence of complete spinal cord transection.
• Significant concomitant head injury with a clinically significant abnormality on a head computed tomography (CT).
• One or more upper extremity muscle groups untestable (e.g., immobilized or restricted by a cast) during the screening International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) examination.
• Known receipt of any other investigational product within 30 days or 5 half-lives of the drug (whichever is longer) prior to the first dose of study drug or is currently enrolled in another clinical study.
• Female who is pregnant, breastfeeding, or considering becoming pregnant during the study or for within 39 weeks (5 half-lives) after the last dose of study drug.
• The cause of the acute SCI is one of the following: from gunshot or penetrating/stab wound; non-traumatic SCI, results of seizure, or known attempted suicide.