National Institutes of Health, enrolled the first participants into a Phase I clinical trial testing an mRNA vaccine (mRNA-1273) encapsulated in lipid NPs—a record time of just 63 days following sequence selection (NCT04283461).65 The enrollment of the first cohort of participants (18 to 55-year-old healthy subjects) concluded on April 16, 2020.66 CureVac and BioNTech (in partnership with Pfizer) are currently working on similar vaccines; Pfizer/BioNTech, in particular, have recently started the recruitment in Phase I/II trials (NCT04368728, NCT04380701).