Biogen’s second phoenix — this time ALS?

Odds are low that Biogen could pull off another back-from-the-dead maneuver to get a second failed Phase III therapy approved based on biomarker data, but it might be rational for the company to try, given the strong genetic rationale for the target in ALS and FDA’s recent willingness to approve Aduhelm and a handful of other therapies based on such arguments.

Without another trial, it would be difficult to know with any certainty whether the company’s argument for tofersen’s treatment effect in amyotrophic lateral sclerosis is valid. That trial could be pre- or post-market...