FDA gives Biogen ALS drug a chance

July 26, 2022

Biogen announced this week that the FDA has accepted a New Drug application for its new investigational drug meant to treat a genetic form of amyotrophic lateral sclerosis (ALS). 

The drug, intended to treat superoxide dismutase 1 (SOD1) ALS, received priority review and a PDUFA date of January 25, 2023. 

The application is a gamble for Biogen, considering that back in October, the drug proved no better than a placebo at slowing progression in a phase 3 trial. Biogen is now betting on tofersen’s effect on neurofilaments for ALS management.

Neurofilaments are normal proteins found in healthy neurons that are increased and used as a marker for neurodegeneration. In recent studies, Biogen reports that the drug causes a reduction of these proteins. The NDA hinges on results from a phase 1 study in healthy volunteers, a phase 1/2 study evaluating ascending dose levels, the failed phase 3 VALOR study, and the open-label extension (OLE) study. 

“The 12-month results showed that individuals with SOD1-ALS who started tofersen earlier experienced a slower rate of decline in clinical and respiratory function, strength and quality of life. These are critical measures for people living with this devastating disease,” said Timothy Miller, principal investigator of VALOR.  “For people in my clinic living with SOD1-ALS, tofersen may meaningfully slow the rapid progression of their disease and the impact it has on their lives.”