Someone else answered correctly saying an EUA can't be issued if an already licensed drug can help. I would further that point by saying to actually go dig up the true source of that policy on the FDA's website in your country (not someone's summary or interpretation). It's a great exercise that will leave you with some sort of ground truth in this mess.

Same as in coding, you eventually reach a point where you learn that when in doubt, you must read the source.

It's the way that emergency authorisation use works with FDA. They won't issue that if there are other safe viable treatments. These vaccines got that approval because these other options were suppressed.

>Xofluza, Relenza, and Tamiflu

None of them are as effective as Ivermectin (allegedly). It is only logical that efficacy is also important.