Pink Sheet analysis finds that evidence from early-stage trials supports most BTD requests, but about three in 10 designations are granted on the basis of pivotal-stage data.

FDA confidence to devote time and resources for a breakthrough product resonates with investors and analysts, but the real program value in terms of product sales is yet to be seen. Sponsors also must be careful to manage investor expectations once the breakthrough designation is secured.

Janet Woodcock says agency still cannot detail specific criteria for the popular incentive, but data on breakthrough requests show common characteristics.