- Cohort 1: Approximately one hundred and thirty-eight (138) subjects will be randomized and dosed as follows: seventy-five (75) subjects with the lowest non-adjuvanted dose of the quadrivalent VLP vaccine, nineteen (19) subjects with the medium non-adjuvanted dose of the quadrivalent VLP vaccine, nineteen (19) subjects with the lowest adjuvanted dose of the quadrivalent VLP vaccine and twenty-five (25) subjects with a placebo. The 7-day safety data after the immunization will be collected by the clinical staff and will be reviewed by the Data and Safety Monitoring Board (DSMB). The DSMB consisting of the PIs, the Sponsor's Medical Officer and 3 external medical advisors (voting members); the members will determine if the clinical sites are allowed to continue with the immunization of the second cohort.