[Treatment of familial ALS with the drug tofersen]

Amyotrophic lateral sclerosis (ALS) is a severe and progressive neurodegenerative disorder. We describe four cases of familial ALS based on SOD1 mutations who received intrathecal treatment with the antisense oligonucleotide tofersen at Landspítali University Hospital Iceland. Since initiation of treatment, there has not been any significant deterioration, and three patients have shown signs of cinical improvement. The cerebrospinal fluid concentration of neurofilament light chain (Nf-L), a biomarker of neuronal axonal damage, has decreased to the reference range of healthy individuals. No serious side effects have been observed.