A Study to Learn About the Effect of Nusinersen (BIIB058) Given as Injections to Children With Spinal Muscular Atrophy (SMA) Who Were Previously Treated With Onasemnogene Abeparvovec (RESPOND)

Children's Hospital Philadelphia - Neurology, Philadelphia

Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan

Universitaetsklinikum Hamburg-Eppendorf, Hamburg

Children's Hospital of The King's Daughters, Norfolk

Hospital Universitario La paz, Madrid

Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago

Arkansas Children's Hospital Research Institute, Little Rock

Children's Hospital Colorado, Aurora

University of Utah, Salt Lake City

Stanford Neuromuscular Research, Palo Alto

Oregon Health and Science University (OHSU), Portland

Schneider Children's Medical Center, Petah Tikva

Massachusetts General Hospital, Boston

Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma

Hospital Sant Joan de Déu, Esplugues Del Llobregat