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

Canonical page: https://technooptimist.io/stories/fda-grants-accelerated-approval-to-qalsody-the-first-treatment-8e3330b4
Date: 25 Apr 2023
About: [Biogen](https://technooptimist.io/companies/biogen.md) · [Qalsody (tofersen)](https://technooptimist.io/biotech/qalsody.md)
Original source: https://www.sec.gov/Archives/edgar/data/874015/000114036123020335/brhc20051944_ex99-1.htm

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.

## Key facts

- 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.

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