It typically costs ~$2B to develop a new drug. Taxpayer contributions are practically negligible.
P.S. I worked for J&J once, seen their inefficiencies first-hand.
US companies cannot really charge more than European companies [+]. They all charge more in the US and less elsewhere.
[+] In general, there are also cases where the same drug is marketed by a US company in the US and a non-US company in the rest of the world.
And how much more/less effective is Remdesivir compared to the generic Dexamethasone anti-inflammatory?
https://blogs.sciencemag.org/pipeline/archives/2017/10/18/dr...