Yes, it definitely could be this which is why I said "my gut suspects the arduous FDA approval process." This could be the source of a lot of that fixed cost. I'd be generally curious to see data on what is involved in starting up a new production line for these kinds of pills.

Is there a chemist in the house? :)

If fixed prices inherent to the production of the drug were the key then I wouldn't expect a manufacturer would be able to provide this same drug in the UK for $2 without going out of business. Now, there are probably reasonable health and safety procedures done in the UK but not in Tanzania that bump the price up that much which I want done to my drugs as a wealthy resident of the first world but which I might not be able to afford if I were a Tanzanian. But $400 is clearly not required to make the drug up to reasonable safety standards.