Previous studies offer few data on the course of NfL levels in ALS patients with high BL values: in the VALOR study investigating tofersen in SOD1‐associated ALS, patients with high BL NfL levels receiving placebo (n = 21) showed a 20% increase in NfL levels after 28 weeks [24]. The gene discussed is NEFL; the disease is amyotrophic lateral sclerosis.