Let's not forget insulin formulations are ancient yet generics don't exist for "reasons". It's as corrupt as it gets.
http://insulinnation.com/treatment/why-walmart-insulins-aren...
In the US of all places, there isn't a good argument for the very, very slightly modified newer insulins to cost so much more.
(these points are alluded to in the article, just want to mention them here, as well)