(and then horseshoe crabs and recombinant factor C)
The FDA should figure out if fFC works and then mandate use of it if it works.
About 60k doses/lot, figure 30 endotoxin tests per lot, that's 1 test per 2k doses =~ 300k endotoxin tests to vaccinate the US.
"For now, the industry says it has plenty of horseshoe crab blood to screen coronavirus vaccines. Pharmaceutical companies test a sample from a batch of vaccines, not every dose. And that sample size, say three vials, doesn’t change whether the batch contains 100,000 doses or 1 million, says Allen Burgenson of Lonza.
In fact, Burgenson says, the industry produces enough tests in one day to screen 5 billion doses of coronavirus vaccine."
(I think this is unduly optimistic, because mfrs are likely to screen at multiple steps during production, since the latency of batches is ~100 days, and because lot sizes aren't so large yet. So divide 5 billion by a small integer).
There's no use of intact animals to make these vaccines. I don't think there are any use of animal cell cultures in any of the mainline vaccine paths (though there are some human cell lines used in the adenovirus, etc, vaccines that many people consider problematic).