IVT mRNA can be created by incorporating naturally occurring modified nucleosides such as 2-thiouridine, pseudouridine, 5-methylcytidine, 5-methyluridine, or N6-methyladenosine into the IVT mRNA. This has been shown to suppress both the intrinsic adjuvant activity of IVT mRNA as well as its inhibitory effects on translation.

https://mrna.creative-biolabs.com/mrna-pharmacology-optimization.htm