This ethical question is particularly interesting. Just to play Devil's Advocate, let's assume that Big Pharma is not involved. Rather, the people who are doing the research are honest researchers who gain utility through the act of research and finding breakthroughs.

If phrased this way, the incidents may suddenly now be sympathized as being yet another statistic - after all, sacrifices must be made in the name of scientific progress. The matter of coercion becomes trivial in the sense of The Greater Good (of course, not all research will yield positive results, and that's the whole point of research).

Now, if one were to have this sort of view going into doing medical trials, who's to say that one's wrong? Why is it still evil, if the net result are better drugs to control one's moods?