Hi All,

I found that interesting as well. I believe the partial answer to your question is that there are unexpected results sometimes, even if extensive animal trials have been done. There can be cases where we would expect certain side effect, but in reality, they are much worse than first thought.

I looked up to see if there were any recent cases of this occurring and found a case from a little over a year ago. A new painkiller was in clinical trials after undergoing pre-clinical trials on animals. It was a trial done on six patients, and all faced severe side-effects with one being brain-dead. There was a number of investigations launched into this accident, but I was unable to find the outcome. However I think it is clear from this case that when these accidents do occur, the company needs to ensure they followed all guidelines for proper clinical trials.

Source: http://www.sciencemag.org/news/2016/01/more-details-emerge-fateful-french-drug-trial

-Andrew Nashed