What ‘Confirmatory Evidence’ Does US FDA Need When Sponsors Want To Rely On A Single Trial?

10 Oct 2022

Amylyx’s Relyvrio survival data, drawn from a post hoc exploratory survival analysis of randomized patients, and the primary ALS functional endpoint ‘capture distinct concepts,’ FDA states. Use of long-term survival data from the same trial as confirmatory evidence was unusual, but not unique.

Outside the box — Relying on post hoc overall survival data as confirmatory evidence suggests some outside the box thinking by US FDA. • Source: Shutterstock

The US Food and Drug Administration’s approval of Amylyx Pharmaceuticals, Inc.’s amyotrophic lateral sclerosis drug Relyvrio (sodium phenylbutyrate/taurursodiol) has brought new focus to when the agency will accept confirmatory evidence to support approval on the basis of a single adequate and well-controlled trial.

In approving Relyvrio (previously known as AMX0035), the agency said data on an overall survival benefit can serve as confirmatory...