Innovation Pharmaceuticals Inc (IPIX)

[Orion Nebula]

I have been thinking about the main protease binding site and the issue of mutability.

https://www.biorxiv.org/content/10.1101/2020.02.27.968008v1.full.pdf

Here is my thinking:
1) B is an antiviral candidate although it may prove useful as an adjuvant as well. A vaccine will limit the usefulness of B for Covid 19 in the future so the mutability of Mpro may be a moot point.
2)The spike protein mutates as well. Recent reports point out the emergence of a more dangerous strain from a spike protein mutation. So it is hard to make a case the spike is a more attractive target. The spike is used for cellular attachment so there is appeal if you prevent attachment. But Mpro provides many opportunities to wreak havoc on the virus, including the lipid coat.
3) The complete picture is hard to fathom given the modulatory and antibacterial effects of B.

Bottom line, we do not know if mutability will require reformulation of a vaccine on annual basis, much like the flu. Likewise, over time the effectiveness of antiviral treatments is subject to the same variable.