Tofersen adcom raises hopes of even more FDA flexibility

So much for a new, stricter regimen at the FDA’s neurology division after the departure of Billy Dunn, who was something of a patron saint of lost causes. Biogen/Ionis’s tofersen looked finished 18 months ago, but now seems set for accelerated approval in Sod1-mutated ALS at the very least: at yesterday’s FDA advisory committee meeting panellists were unanimously in favour of using the controversial biomarker neurofilament light chain to predict a clinical benefit. Full approval looks like a longer shot, but could still happen after a close vote – it seems incredible that this was even discussed, given the project’s phase 3 failure. Biogen is already carrying out the Atlas trial in presymptomatic patients, which could be used as a confirmatory study, owing to the difficulties in carrying out a new study in such a small population. The rarity of Sod1 ALS means tofersen is not expected to become a big money-spinner, but the panel outcome appears to signal continuing flexibility at the FDA around CNS biomarkers. This could be good news for the likes of Uniqure, Denali, Dyne, Pepgen and Alector, as well as other pipeline assets from Biogen and Ionis, Stifel analysts noted.