Can any of the more scientific minds on this site give a more detailed explanation of what this bolded statement from the PR means:

We have completed our ex vivo human trial of COVID-19 patient samples and can confirm that the results of the T cell activation and antibody screen have enabled us to select Ii-Key-SARS-CoV-2 epitopes for our vaccine formulation. I will provide an update on these results as well as the results of our ongoing immunogenicity study that will confirm the commercial viability of our Ii-Key vaccine.

Would that just be further analysis of the blood samples that came out of the ex-vivo study? Or would this be some additional testing?

Thanks!