Phase 12a Randomized Trial of Intranasal BLB-201 Vaccine for Prevention of Respiratory Syncytial Virus in Infants and Young Children Aged 8 Months to 5 Years

What this Trial Is About

Researchers are evaluating the safety, tolerability, and immune response of the BLB-201 vaccine, delivered intranasally, in infants and children aged 8 months to 5 years. This Phase 12a randomized, placebo-controlled trial includes participants who may have had prior respiratory syncytial virus RSV infection. The study aims to assess two different vaccine doses in this young population to better understand the vaccines effects and safety profile. Participants will receive either a low dose 106 PFU or a high dose 107 PFU of the BLB-201 vaccine or placebo. Some participants will receive one dose on Day 1, while others will receive two doses on Day 1 and Day 57. The vaccine and placebo are given by intranasal administration. The trial includes groups of both RSV seropositive and RSV seronegative infants and children. During the study, participants will be closely monitored for adverse events from Day 1 through Day 29, with specific attention to solicited events from Day 1 to Day 15. Medical history, physical exams, and laboratory tests will be conducted to evaluate health status and immune response. Parents or legal representatives will provide informed consent and confirm routine immunizations are up to date. The total study duration extends until the primary completion date in late 2028, with ongoing safety and immunogenicity assessments throughout this period.

A Study of BLB-201 RSV Vaccine in Infants and Children