In this sub-study, approximately 400 adults participants who are generally healthy or with stable pre-existing health conditions aged ≥ 20 to < 65 years will be enrolled. The first 250 participants enrolled in this sub-study will receive MVC-COV1901(Scale A) and the remains will receive MVC-COV1901(Scale B). Each participant will receive 2 doses of study intervention, administered 28 days apart via IM injection in the deltoid region, preferably of the nondominant arm, at Day 1 and Day 29. The study procedure and visit schedule refer to the main study protocol and will be the same as the study procedure for the Immunogenicity Subset.
This sub-study is a prospective open-label, single-center study to demonstrate comparability of different manufacturing scales.