[Articles] Safety and immunogenicity of mRNA-based mpox vaccine candidate BNT166a: an open-label, dose-escalation, first-in-human trial

The study examined the safety and efficacy of an experimental mRNA vaccine BNT166a against mpox in participants with and without prior vaccinia immunity. The vaccine was well tolerated, with adverse events occurring more frequently after the second dose than the first. BNT166a efficiently induced antibodies against multiple mpox antigens, which persisted for up to 12 months. The vaccine demonstrated neutralizing capacity against mpox clade IIb and vaccinia virus, although with a gradual decline in long-term response. The safety and immunological profile of the vaccine supported its advancement to phase 2 clinical trials.