Current regulatory requirements for clinical trials of viral vaccines

Abstract

Scientific relevance. In recent years, the development of various vaccines based on novel platforms has underscored the significance of updating regulatory requirements for vaccines. Consequently, clinical trials of viral vaccines need harmonised approaches within national guidelines and the Eurasian Economic Union (EAEU) regulatory framework.Aim. This study aimed to analyse national and international requirements for clinical trials of the efficacy and safety of preventive viral vaccines.Discussion. This article presents an analysis of the guidelines issued by the WHO and leading regulatory authorities on different aspects of clinical trials of viral vaccines. These guidelines place particular emphasis on the immunogenicity of vaccines. The lack of well-established immune correlates of protection for most infections presents a significant problem for assessing the effectiveness of vaccines. Immunobridging studies may be conducted to expand vaccine indications to different populations (such as a new age group). The size of the prelicensure safety database should include data on at least 3,000 vaccinated study participants. For some vaccines, safety studies must assess the risk of disease onset or enhancement due to vaccination.Conclusions. The clinical trial requirements for viral vaccines have been substantially aligned by the WHO and major international regulatory authorities, thereby facilitating the development of harmonised national or EAEU guidelines.