It isn’t overly expensive. Most insurances will cover it, but if they don’t it’s about $100 to 200. It's around 25 EUR in Germany. https://archive.is/dyY3Q
This is in the US where we aren’t burdened with inefficient, government-controlled health care. /s
German Tax Rates for an individual:
$58,918 - $274,612: 42%
US Tax Rates for an individual:
$40,126 - $85,525: 22%
$163,301 - $207,350: 32%
So, if you make an average salary of roughly 40-90k, you pay a full twice as much in taxes, for an extra $9,228 to $20,700 each year.
That extra ~$10,000 to ~$20,000 dollars you pay in Germany in taxes, then (a portion of it) goes to pay for the health care.
The drug isn't just magically cheaper, they just pay for it via taxes instead.