The primary source of clinical evidence presented by the company was the phase III, open-label, single-arm, multicentre SPR1NT trial, which assessed the efficacy of onasemnogene abeparvovec as a treatment for patients with pre-symptomatic SMA and two (n = 14) [17] or three (n = 15) [18] copies of the SMN2 gene. The gene discussed is SMN2; the disease is proximal spinal muscular atrophy.