There are times where the government, can, and should drop in and buy the entire IP associated with a medication. This price should be set with a council of various representatives, and it should not be something that the drug manufacturing company can reject.
Most of the research here is already partially funded by the tax payer through Government funds of colleges, etc etc anyway.
This isn't even something unheard of. The US has the power to unilaterally cancel patents.
For what price?
This is part of the cost of doing business. If a drug company is going to close shop and want to go operate in Europe or China, that's a risk we should be fine taking.
Drug X was funded for development for $XXX million because it was perceived to have a strong positive expected ROI dependent on selling the drug for $Y leading to an expected value of $ZZZ million.
If you're offering $ZZZ million for it then the drug companies won't complain but you're just having the public pay the total cost up front. If you're offering substantially less than $ZZZ million, then the drug company will not invest $XXX million because you've just slashed he potential ROI.
Private R&D can still fund development and set prices how they want. But they’ll have to compete with publicly funded alternatives.
The shame is that NIH already provides an incredible quantity of funding, but it certainly doesn’t result in the US getting any better drug prices…
More likely they are two different treatments that maybe take the same general approach. If the publicly funded one is available at cost, the private one would have to be significantly better to make any money.
It would be great if the public developed useful, novel drugs. But if you're proposing a system where the private side can still develop them, patent them, and sell them at a high price; then it's not really different from today. You shouldn't assume that both parties would solve problems independently and redundantly. It doesn't even really make sense to pursue alternative development. If there's a cure for X; are you REALLY going to encourage public researchers to find a different cure for the same thing to try and lower the cost of the drug? That sounds like a very ineffective approach.