A Long-Term Extension Study of Nusinersen (BIIB058) Administered at Higher Doses in Participants With Spinal Muscular Atrophy Who Previously Participated in an Investigational Study With Nusinersen
To evaluate the long-term safety and tolerability of nusinersen administered intrathecally at higher doses to participants with SMA who previously participated in Study 203. To evaluate the long-term efficacy of nusinersen administered intrathecally at higher doses to participants with SMA who previously participated in Study 203.
