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NfL makes regulatory debut as neurodegenerative disease biomarker
The FDA approved tofersen for amyotrophic lateral sclerosis based on the drug’s ability to lower blood levels of neurofilament light (NfL) — establishing a proof of potential for this neuroscience biomarker that could have implications for other diseases of the brain.
With the FDA’s accelerated approval of Biogen and Ionis’s tofersen in April, patients with a rare form of amyotrophic lateral sclerosis (ALS) gained access to a new treatment with promising but as yet unproven evidence of efficacy. Drug developers similarly gained hope for an up-and-coming biomarker called neurofilament light (NfL) that could help to accelerate the hunt for drugs for neurodegenerative diseases.