Despite a failed phase III study, the U.S. FDA suggests in briefing documents that tofersen (BIIB-067) is effective for treating the rare, genetic disease superoxide dismutase 1 amyotrophic lateral sclerosis (ALS). The intrathecally injected therapy is being developing by Biogen Inc. and Ionis Pharmaceuticals Inc. and is at the heart of a March 22 meeting of the agency’s Peripheral and Central Nervous System Drugs Advisory Committee (adcom).