IMPAACT 2038

IMPAACT 2038 is a Phase I, double-blinded, placebo-controlled, randomized study that will evaluate the infectivity, safety, and immunogenicity of recombinant, live-attenuated bovine/human, parainfluenza virus type 3 (B/HPIV3) vector vaccines B/HPIV3/RSV/PreF, B/HPIV3/RSV/PreF/TM, or placebo in HPIV3-seronegative children. Approximately 70 healthy HPIV3-seronegative children ≥6 months (180 days) to <25 months (750 days) of age will be enrolled. Eligible children will receive a single intranasal dose of B/HPIV3/RSV/PreF vaccine, B/HPIV3/RSV/PreF/TM vaccine, or placebo at entry. Participants will be enrolled in the study outside the time during which wild-type RSV circulates in the community at each study site and will remain on study with follow-up visits through Day 28 after receipt of study product and non-visit contacts thereafter to monitor for adverse events.