SMN1 and proximal spinal muscular atrophy: On the other hand, for spinal muscular atrophy (SMA), the administration of intrathecal nusinersen is mandatory, despite the COVID-19 pandemic, due to the proven worsening of clinical and functional condition with delayed treatment in particular for SMA 1 and young children with SMA 2, while for the adolescent or adults, injections could be delayed for a maximum of 4 months from the last administration (36, 37).