A Safety and Immunogenicity Study of Intranasal Sendai Virus Vectored Respiratory Syncytial Virus (SeVRSV) Vaccine in Healthy Adults

This is a Phase I randomized, double blind, placebo controlled trial in up to 25 males and non-pregnant females, 18-45 years old, inclusive, who are in good health and meet all eligibility criteria. This trial is designed to assess the safety, reactogenicity and immunogenicity of a single intranasal dose of Sendai virus vectored Respiratory Syncytial Virus (SeVRSV) vaccine. The subjects will be randomly assigned in a 4:1 ratio to receive SeVRSV vaccine at a dose of 1 x 10\^7 EID50 or placebo (saline) intranasally. Since this is a first in human, phase I study, the first two subjects (sentinels) will be enrolled in the SeVRSV treatment arm. Safety and laboratory data will be collected through 14 days post vaccination. If none of the predefined halting criteria of sentinel subjects are met, enrollment of the remaining subjects will proceed. If any of the pre-defined halting criteria of sentinel subjects are met, an electronic review by the SMC will be required prior to continuation of the study. While safety is evaluated for the sentinel subjects, no new subjects will be enrolled, but screening may continue. Study duration is approximately 11 months with subject participation duration approximately 6 months. The primary objectives are to: 1) assess the safety and reactogenicity of SeVRSV vaccine following receipt of one intranasal dose; 2) assess the ELISA antibody responses to SeV and to the RSV F protein at 28 days post receipt of one intranasal dose of SeVRSV vaccine; 3) assess the detection of vaccine virus from nasal washes at days 3, 5, 8 and 15 following receipt of one intranasal dose of SeVRSV vaccine.