I am a nuclear medicine physician. The approval mechanism for PET tracers is far too slow. Patients and clinicians sometimes call me, frustrated, that there is a very promising tracer for their disease, often studied and published in the literature for five years or more, that is still not available clinically. Unless they want to move to some city that has an open trial, which would mean leaving all their current treating physicians, not to mention their home, family, and friends, they simply cannot have the test.
It is my professional opinion that streamlining the approval process would help a lot of people.