I don't mind that it takes a little proof to convince regulatory boards to approve medicines for Phase I trials, but these days Phase I trials are fairly quick to get (assuming you can sell the doctors and patients on it).

My guess for the delay is production process and delivery mechanisms. There are delivery mechanisms where the combinatory effects lead to some serious toxicity.

Plus, how long do mice live for? I'm sure they are still taking down observations and collecting data. The article submission may be to help with funding.

I wonder how much of our regulation around medicine is wasteful, vs regulation that came about in response to some sort of malfeasance.

Most of it is probably both.

I worked in medical devices, and that is correct. Much of the work I did in the QA dept would not have improved the product or safety, but some of it clearly did. Can't say for medicines, as they had a different set of regs from devices.

It is both. The last time we had very free experimentation (read: disregard for human life and suffering) we got the Nazis, the Tuskegee Syphilis Study, MKUltra, etc.. So institutions swung strongly in the opposite direction (the visible ones, at least), giving us Institutional Review Boards and such. The balance is impossible to get right either way, hence the need for Right to Try and so on.