In other words, blame the game. From where I come from it seems very strange that medical services / prescribed medicine has free floating 'market prices' in the US. There is no such thing as a functioning market for these products - you have complete information asymmetry as well as government enforced monopoly on medication (pharmaceutical patents). Letting the providers set the price is just asking for trouble. Negotiating medical prices on government level and setting fixed prices for medical services (adjusted periodically) is absolutely necessary for a functioning general healthcare.
I'm honestly looking for an answer here. Maybe there is a good reason Valeant can and should be able to get away with it.