Biogen presented new data from the Phase 3 ENDEAR study of SPINRAZA™ (nusinersen), which demonstrated a statistically significant reduction in the risk of death or permanent ventilation in SPINRAZA-treated infants with spinal muscular atrophy (SMA) compared to untreated infants. The data were presented at the British Paediatric Neurology Association (BPNA) annual conference in Cambridge, UK, 11-13 January 2017. In August 2016, Biogen reported that ENDEAR met its pre-specified primary endpoint at the interim analysis, the proportion of motor milestone responders as measured by the Hammersmith Infant Neurological Examination (HINE). Following the positive interim analysis, Biogen ended the study early so that all participants could have the option to receive SPINRAZA in an open-label extension study. SPINRAZA met the pre-specified primary endpoint at the ENDEAR EOS, demonstrating a statistically significant 47% reduction in the risk of death or permanent ventilation - pSPINRAZA Program Status Biogen licensed the global rights to develop, manufacture and commercialize SPINRAZA from Ionis Pharmaceuticals. Biogen and Ionis conducted an innovative clinical development program that moved SPINRAZA from its first dose in humans in 2011 to its first regulatory approval in 2016. Efficacy and safety data from the ENDEAR interim analysis, as well as open-label data in pre-symptomatic and symptomatic patients with, or likely to develop, Types 1, 2 and 3 SMA, supported the FDA approval of SPINRAZA in the U.S. for the treatment of SMA in pediatric and adult patients, representing the first approved treatment for individuals with SMA.