An Open Label Clinical Study to Evaluate Tanruprubart (Also Commonly Known as ANX005) in Participants With Guillain-Barré Syndrome (FORWARD Study)

Key Inclusion Criteria: * Diagnosis of GBS according to the National Institute of Neurological Disorders and Stroke Diagnostic Criteria for GBS. * Onset of GBS-related weakness ≤10 days before start of infusion on Day 1 * GBS-disability score (DS) score of 3, 4, or 5 at screening and before start of infusion on Day 1. Key Exclusion Criteria: * Previous or intended treatment with either plasma exchange or IV immunoglobulin for GBS. * Diagnosis of a variant of GBS, including Miller Fisher syndrome, Bickerstaff's encephalitis, and overlap syndromes. Other protocol-defined criteria may apply.