Table 1.
Comparison of the emerging circRNA vaccines
| Vaccine | Target immunogen | RNA circularization strategy | Delivery method | Structure to initiate translation |
|---|---|---|---|---|
| circRNARBD | SARS-CoV-2 RBD (receptor- binding domain) antigen | Enzymatic and ribozymatic (T4 RNA (group ligase) I intron autocatalysis strategy) | LNP | CVB3 IRES |
| VFLIP-X | SARS-VFLIP-CoV-X 2 spike protein | Enzymatic (T4 RNA ligase) | LNP | CVB3 IRES |
| Cytokine-encoding circular mRNA | 4 cytokines (active IL-15, IL- 12sc, GM-CSF, IFN-a 2b) | Ribozymatic (group I intron autocatalysis strategy) | LNP | E29 IRES |
| circRNAOVA-luc-LNP | OVA (257–264)-luciferase | Ribozymatic autocatalysis (group strategy) I intron | LNP | CVB3 IRES |