Randomized, double-blind, phase III, pivotal field trial of the comparative immunogenicity, safety, and tolerability of two yellow fever 17D vaccines (Arilvax and YF-VAX) in healthy infants and children in Peru.

We conducted a randomized, double-blind, phase III yellow fever (YF) vaccine trial among 1,107 healthy children in Sullana in northern Peru. The safety and efficacy (by measurement of geometric mean neutralizing antibody titer responses) were determined for two YF vaccines, ARILVAX (n = 738) and YF-VAX(R) (n = 369). Serocon-version rates were higher (94.