This study aims to check how safe and well-tolerated a second dose of RSVpreF is when given during later pregnancies, and to see how long the immunity lasts from a single dose given during a previous pregnancy by examining the blood of nonpregnant participants who had the vaccine before.
Protocol Amendment History
25 amendments
This ClinicalTrials.gov record has been amended 25 times since 2025-03-04; most recent amendment 2026-07-07.
Status change: Not Yet Recruiting → Recruiting2025-04-30