Standard of Evidence Expanded in New FDA Guidance

The FDA yesterday proposed broadening its definition of the standard of evidence for effectiveness of investigational drugs and increasing the range of acceptable trial design, especially in rare disease research.

In its first updated guidance in more than 20 years on acceptable trial design, the FDA said substantial evidence from a trial proving effectiveness could be gained from one trial instead of two, one adequate well-controlled trial plus confirmatory evidence or reliance on a previous finding of effectiveness from an approved drug.