Hard to do large clinical trials

That is the title of an Arnold Kling blog post, it runs like this (I am not adding an extra layer of indentation):

Speaking this week at the EmTech conference in Cambridge, Massachusetts, Editas CEO Katrine Bosley said the company hopes to start a clinical trial in 2017 to treat a rare form of blindness using CRISPR, a groundbreaking gene-editing technology.

…The condition Editas is targeting affects only about 600 people in the U.S., says Jean Bennet, director of advanced retinal and ocular therapeutics at the University of Pennsylvania’s medical school.

I don’t think that the FDA is prepared for what is coming.”