Approved RNA medicines show a correlation between the type of RNA and specific modifications (Table ). The mRNA vaccines BNT162/Comirnaty and mRNA-1273/Spikevax have 7methylguanosine caps connected to the 5' end of the mRNA by a triphosphate group and have all their uridines replaced with 1-methylpseudouridine, which improves mRNA stability and translation.