A Phase I Study of the Safety and Immunogenicity of a Single Dose of the Recombinant Live-Attenuated Respiratory Syncytial Virus Vaccine RSV ΔNS2 Δ1313 I1314L, Lot RSV#006A, Delivered as Nose Drops to RSV-Seropositive Children 12 to 59 Months of Age, RSV-Seronegative Infants and Children 6 to 24 Months of Age, and Infants 4 to 6 Months of Age
Human respiratory syncytial virus (RSV) is a common cause of respiratory illness in infants and children around the world. This study will evaluate the safety and immune response to a RSV vaccine in three groups of participants: healthy children who have already had an RSV infection (RSV seropositive), healthy infants and children who have not already had an RSV infection (RSV seronegative), and healthy younger infants who have not been screened for prior RSV infection.
• Healthy children at least 12 but less than 60 months of age, whose parent/guardian understands and signs the study informed consent and who agrees to vaccine administration following a detailed explanation of the study
• Seropositive for RSV as defined by serum RSV neutralizing antibody titer equal to or greater than 1:40. If a child at least 12 but less than 60 months of age is determined to be RSV seropositive prior to Day 56, s/he does not need an additional screening serum specimen, but a pre-inoculation serum specimen must be obtained.
• Participant's history has been reviewed and participant has undergone a physical examination indicating that s/he is in good health
• Participant is expected to be available for the duration of the study
• Healthy children at least 6 but less than 25 months of age whose parents/guardians can understand and sign the informed consent and who agree to vaccine administration following detailed explanation of the study
• Seronegative for RSV antibody, defined as a serum RSV neutralizing antibody titer less than 1:40 as determined not more than 42 days prior to inoculation
• Participant's history has been reviewed and participant has undergone a physical examination indicating that s/he is in good health. Permitted concomitant medications include nutritional supplements, medications for gastroesophageal reflux, eye drops, and topical medications, including topical steroids, topical antibiotics, and topical antifungal agents.
• Participant is expected to be available for the duration of the study
• Healthy infants 4 to 6 months of age whose parents/guardians can understand and sign the informed consent and who agree to vaccine administration following detailed explanation of the study.
• Subject's history has been reviewed and subject has undergone a physical examination indicating that s/he is in good health. Permitted concomitant medications include nutritional supplements, medications for gastroesophageal reflux, eye drops, and topical medications, including topical steroids, topical antibiotics, and topical antifungal agents.
• Subject is expected to be available for the duration of the study.
• Those children who have completed the initial study and whose parents/guardians can understand and sign the informed consent.
• Subject is expected to be available during the second year of RSV surveillance.