I think the best vaccine or way to prevent or otherwise mitigate the Trumpence-demic plaguing America and the world is to defeat Donald Trump.
In fact the Trumpence-demic has already made any vaccine mute for the over 200,000 Americans killed and over 2,000,000 more Americans who will have health issues the rest of their lives.
That is I fail to see how a vaccine before the election would save Trump because it is already to late to save America from the Trumpence-demic.