A Trial to Evaluate Safety, Tolerability, and Immune Responses of an Investigational Monovalent Chimpanzee Adenoviral Vectored Sudan Ebolavirus Vaccine in Healthy Adults

This is a multi-center, double-blinded, placebo-controlled, Phase 2 study to evaluate safety, tolerability, and immunogenicity of a single dose of cAd3-Sudan Vaccine in healthy adults up to 70 years of age. The study will enroll 200 eligible participants randomized 4:1 to receive the cAd3-Sudan Vaccine at 1.0 × 10\^11 PU dose or placebo (0.9% sodium chloride (NaCl) solution) at Day 1, intramuscularly in deltoid muscle. Participants will be screened for eligibility up to 28 days before enrollment. Safety data will be periodically reviewed by an independent DSMB. Safety and immunogenicity will be assessed at Days 1, 8, 15, 29, 85, 169, and will conclude at the end of study visit on Day 366. PBMCs will be collected from a subset of 40 subjects on days 1, 15, 29, 169 and 366 to access cellular immunity.