[Clinical research design and challenges of multi-conjugate vaccine and polyvalent vaccine]

Multi-conjugate vaccine and polyvalent vaccine can reduce the number of vaccinations, improve vaccination efficiency, and provide wider protection against diseases, and can not only brings convenience to recipients but also reduce healthcare costs, making it a key focus in modern vaccine development. However, even if the components of the vaccine are derived from already approved monovalent vaccines, it must still be considered as a new vaccine and undergo randomized controlled clinical trials to evaluate their safety and efficacy in humans. Due to the inclusion of multiple antigens, clinical evaluation must consider the potential interactions between or among the components, as well as the impacts of adjuvants, preservatives, and other ingredients on the vaccines' safety and efficacy. These factors introduce certain specific challenges in the clinical evaluation of multi-conjugate vaccine and polyvalent vaccine. This article summarizes the key elements and methods of clinical study design for multi-conjugate vaccine and polyvalent vaccine in terms of safety, immunogenicity, and protective efficacy, and discuss the problems and challenges exisitng in vaccine clinical evaluation to provide reference for the standardization of clinical study design of multi-conjugate vaccine and polyvalent vaccine.