A Study to Evaluate the Efficacy and Safety of BIIB093 in Participants With Brain Contusion

Key Inclusion Criteria: * Clinical diagnosis of brain contusion with lesions within the supratentorial brain parenchyma totaling \>3 mL in volume per Investigator assessment of baseline non-contrast computed tomography scan (NCCT) at Screening. * A score of 5 to 15 on the Glasgow Coma Scale (GCS). * Functionally independent, in the opinion of the Investigator, prior to index head injury. Key Exclusion Criteria: * In the judgment of the Investigator, participant is likely to have supportive care withdrawn within 24 hours. * Indication for immediate evacuation of IPH or DC. * Clinical signs of brainstem herniation, in the opinion of the Investigator. * NCCT or magnetic resonance imaging (MRI) evidence of penetrating brain parenchyma. Cerebrospinal fluid leak in isolation is not exclusionary unless evidence of parenchymal penetration by an external force (e.g., blunt object, bullet, or depressed skull fracture). * Any presence of midbrain or posterior fossa injury as assessed by imaging and clinical examination. * Presence of concomitant spinal cord injury as assessed by imaging and clinical examination. * Life-threatening or nonsurvivable polytrauma, per Investigator's judgment. * Use of novel oral anticoagulants (NOACS; including direct thrombin inhibitors such as dabigatran, or Factor Xa inhibitors such as rivaroxaban or apixaban), in preceding 3 days prior to the injury, if known. NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.