rrr: They were from a book written by a US doctor, published a couple of years ago. If I remember correctly, they were aggregated over the previous 5 years.
From reading the scientific press, I do not believe that gene therapy drugs have significantly altered these percentages.
the_doctor: My figures were chance of success to the next phase, so I agree on phase 1 & 2. Your phase 3 percentage (what we're all interested in) looks wrong. Do you have an on-line reference for that?
CFB
I've done some searching and the only online one I can find is: