[shagie]

You are likely looking for the research done on flu vaccinations.

From 2017 https://www.flagshippioneering.com/press/moderna-announces-p...

And also from 2017 Safety, Reactogenicity, and Immunogenicity of mRNA-1653 in Healthy Adults https://clinicaltrials.gov/ct2/show/NCT03392389

The research and testing for mRNA had been a decade in the making and was already present in 2019.

[ekianjo]

You need to do that for every new drug marketed, you can't just refer to prior art.