FDA grants accelerated approval to Qalsody, the first treatment targeting a genetic cause of ALS

Biogen/Qalsody (tofersen)

The FDA approved tofersen (Qalsody) for adults with ALS caused by SOD1 mutations, based on a drop in neurofilament light, a blood marker of nerve damage. In the VALOR trial the drug cut neurofilament by 55% while it rose 12% on placebo; the clinical function score declined less but not significantly over 28 weeks. Continued approval depends on confirming clinical benefit.

• VALOR: 108 patients randomised 2:1; spinal-fluid SOD1 protein fell 35% vs 2%.
• SOD1-ALS is about 2% of ALS, roughly 330 people in the US.
• Given into the spinal fluid: three loading doses 14 days apart, then every 28 days.
• Confirmatory ATLAS phase 3 enrolls presymptomatic SOD1 carriers with rising neurofilament.