Clinical vaccine development

Han, Seunghoon

Human studies of the acceptable safety and reactogenicity of a vaccine candidate are achieved in 'Phase I' clinical trials [18] . In this phase, safety and tolerability are evaluated at both the local and systemic levels as the primary endpoint. Doseranging and/or repeated-dose studies are often performed. Preliminary information on immunogenicity and efficacy may be collected [18, 19] . These trials are often designed as randomized, double-blind, placebo-controlled, single-center studies. According to the characteristics of the product, either a crossover or parallel design may be chosen. The statistical analysis is generally descriptive and exploratory in nature because the trials involve only small numbers of participants , and thus sufficient information needed for confirmatory tests cannot be obtained [19] . In the 'first-in-human' setting, more attention should be given to live attenuated vaccines because the risks tend to be higher than those of killed vaccines [20] .