This is a great case where unregulated free markets absolutely fail to solve the problem. Companies like Impax Laboratories are sole-suppliers, and the cost to produce is the smallest cost, once initial capital costs are laid down to build the factories to produce them. What would happen if a challenger appeared? A new company gets some funding to try to make a small number of high profit drugs, competing with Impax?…
Drugs are heavily regulated in the US.
How can a newcomer get into this market and undercut a competitor who can essentially drop prices as low as they want without losing their profitability?