Amantadine was useful for one big group of influenza viruses, but by the time that it was being pushed for broader use, these viruses had already evolved to evade the effects of amantadine. Researchers certainly looked for other drugs that would block the coronavirus.

Your question seems misdirected. No need for quotation marks when the coronavirus was real. And the vaccines were extensively tested and demonstrated to be safe before release. ALL subsequent tests demonstrate that many more lives were saved than were harmed by the vaccines. Yes, some were harmed.