A phase III clinical trial on the immunogenicity of a tetanus vaccine, adsorbed in individuals aged 18 years and above in China.

To evaluate the immunogenicity of a tetanus vaccine, adsorbed (TTVA) in people aged 18 years and above. A randomized, double-blinded, and positive controlled clinical trial was conducted in Bijie, Guizhou Province, China. Participants aged 18 years and above were recruited and randomly assigned 1:1 to receive the experimental (TTVA) or control tetanus vaccine, adsorbed (TT) vaccine. Serum samples were collected from all participants before vaccination, 30 days after vaccination, and 6 months after vaccination in the first 240 participants to detect tetanus toxoid IgG antibody levels. At 30 days after vaccination, the geometric mean concentration (GMC) of antibodies in the experimental group and the control group were 3.205 and 2.387 (P = 0.0012), the seroconversion rates were 89.07% and 87.47% (P = 0.6149), the seropositivity were 98.38% and 98.79% (P = 0.4850), and the geometric mean increase (GMI) were 35.529 and 27.604 (P = 0.0026), respectively. Six months after vaccination, the GMCs of antibodies in the experimental group and the control group were 1.025 and 0.803, respectively (P = 0.2119), the seropositivity were 98.25% and 95.73%, respectively (P = 0.4008), and the GMIs were 9.466 and 7.661, respectively (P = 0.2106). TTVA vaccine has good immunogenicity in people aged 18 years and above. https://clinicaltrials.gov, identifier NCT06120751.