The price differences between domestic and international medicines can be truly outrageous. I just got back from a work trip to a hospital in Sierra Leone, where the anthelmintic medicine Albendazole costs the equivalent of $1 USD at a private pharmacy (or even less if you don't care about packaging). The same treatment in the US (a single dose) cost me $430 USD (before insurance). This medicine is out of patent; the R&D costs have been recovered. There's no reason for it to cost as much as is does in the US, apart from greed. It's more of a niche drug in the US than it is in sub-Saharan Africa, but it is shelf stable unlike say the antibodies of an immunotherapy, or the rabies vaccine, so it's not perishable. I trust the purity of the US version more than the version sold internationally, but that is probably an irrational fear. Even with added costs of laboratory purity testing and import tariffs, those in the US would still be better off if we could import drugs from overseas.

Some medicines are expensive for a reason: they're new and need to have R&D (and FDA) costs recovered (this is why we have patents), they have niche use and are produced in small quantities (cancer immunotherapies), they're perishable (biologicals), or all three. Many others are expensive because we have no regulatory protections against price gouging. Epi-Pens are another example. A 1mL vial of epinephrine costs ~$5, and the syringe to inject it costs pennies. Auto-injectors add some value, but not the $700 Mylan charges. They're fundamentally a pre-filled syringe a spring, and an injection molded case.

I wonder what the system would look like if we granted longer pharmaceutical patents (say, 30 years), with the change that upon expiration of the patents medicines would be produced by the government and sold at cost (or provided for free).