Biogen (BIIB) announced positive initial data from the pivotal cohort (Part B) of its mid to late-stage study evaluating the safety and efficacy of a higher dose regimen of Spinraza (nusinersen) in previously untreated, symptomatic infants with spinal muscular atrophy (SMA).The investigational higher dosing regimen of Spinraza, an antisense oligonucleotide targeting the root cause of SMA, includes two 50 mg doses 14 days apart, and a higher maintenance regimen, 28 mg, every four months. Please note that the ...