That would be weird, since Daraprim (the drug he hiked) was out of patent, anyone could make and sell it, and in fact a competitor did jut a couple of months later[1]. How was Congress preventing competition?
[1] https://www.cnbc.com/2015/11/30/express-scripts-imprimis-to-...
Patents were a collateral issue. On that collateral issue, one of the issues with patents is that drug companies have a tendency to stop producing drugs towards the end of life of a patent to force patients onto a newly patented drug. This practice could be stopped by allowing generics to produce, market, and sell when the patent holder will not.
[1] https://www.commonwealthfund.org/publications/journal-articl...
What seems to me is that the market was crowded out while the primary producer kept the prices low; when they were raised, the market responded.
The prosecutor picked the fight because they knew he was viewed as such an asshole that there was no way anyone would think any differently of him. It's the reason he's in jail for seven years despite making profits for those he defrauded (remember that sentencing in these cases is often dependent on damages) and Elizabeth Holmes isn't.
Good PR juju goes a long way: https://www.huffingtonpost.com/dr-mariappan-jawaharlal/tale-...