September 3, 2025
The FDA introduces the Rare Disease Evidence Principles to provide greater speed and predictability in the review of rare disease treatments
The U.S. Food and Drug Administration has announced a new Rare Disease Evidence Principles (RDEP) process to create a more predictable and flexible approval pathway for ultra-rare disease treatments.
To qualify, therapies must target:
- rare diseases affecting fewer than 1,000 people in the U.S.
- known inherited genetic disorders
- diseases causing rapid deterioration, severe disability, or death
- conditions with no adequate existing treatments
Under the new framework, sponsors may be able to gain approval based on:
- a single adequate and well-controlled study
- potentially a single-arm trial
- additional robust confirmatory evidence supporting treatment benefit
The aim is to make the FDA’s approach to rare diseases more consistent and predictable, helping patients with some of the most severe and underserved conditions gain access to treatments faster.
