Yellow fever vaccine(Najit Technologies, Inc.)

This trial will be a randomized, placebo controlled, double-blind (within dosing group), dose escalation Phase 1 trial, evaluating dosages of 1 mcg and 5 mcg of HydroVax-002 YFV vaccine given intramuscularly on Day 1 and Day 29 in up to 25 healthy adults healthy adults ≥ 18 and < 50 years of age. The primary objective is to assess the safety, reactogenicity, and tolerability of the HydroVax-002 YFV vaccine administered intramuscularly in a two-dose series on Days 1 and 29 at a dose of 1 mcg or a dose of 5 mcg.