An Investigator Initiated Study of KYV-101, a CD19 CAR T Cell Therapy, in Participants with Treatment Refractory Progressive Multiple Sclerosis (S3.002)

This phase 1 study is to document the presence of KYV-101 chimeric antigen receptor (CAR)-T cells in the central nervous system (CNS) through their detection in cerebral spinal fluid (CSF) and surmise depletion of CNS resident B cells via anti-CD19 CAR-T cells through clearance of oligoclonal bands (OCB)s and/or normalization of IgG index in adult participants with treatment-refractory progressive multiple sclerosis (MS).