I certainly have a limited understanding of this but from what I read...... Regardless of the variant, the COVID virus spike protein attaches to the ACE2 enzyme (viral uptake receptor) on various cell types.  Apabetalone downregulates ACE2 gene expression (via big mRNA reductions). In other words, the barn door is (mostly) shut before the virus can attach and get into the cell. A different variant can't do anything about the ACE2 downregulation that prevents it from attaching and getting in.

And for Omicron, it's way early.  It's looks like it's probably a more transmissible variant, but it's not known how effective the current vaccinations will be, or if it causes a more serious illness.