Table 3.

FDA expedited regulatory pathways (Darrow et al., 2014; Kesselheim and Darrow, 2015; Sinha and Kesselheim, 2016).

Program	Year initiated	Criteria or Data required	Key characteristics
Accelerated approval	1992	− Treatment of serious condition − Early evidence showing advantage over existing therapies	− FDA approval based on surrogate endpoint − Approval granted on conditional basis, post-approval trial required to confirm clinical benefit
Priority review	1992	− Treatment of serious condition or drug is designated as QIDP − Improvement in safety or effectiveness over existing therapies	− Shorter FDA review timeline (six vs. ten months)
Fast track	1997; 2012*	− Treatment of serious condition or drug is designated as QIDP − Preclinical or clinical evidence demonstrating potential to address unmet medical need.	− Rolling NDA review − More frequent written communication from FDA
Breakthrough therapy	2012	− Treatment of serious condition − Demonstrates substantial improvement over existing therapies on one or more clinically important endpoints	− Intensive FDA guidance throughout development to generate additional safety and efficacy data − Largely oncology and orphan diseases

*Fast track designation was amended by the FDA Safety and Innovation Act (FDASIA) in 2012 to include the GAIN Act.

NDA, new drug application; QIDP, Qualified Infectious Disease Product; FDA, Food and Drug Administration.