Safety and immunogenicity of meningococcal (Groups A and C) polysaccharide vaccine in children 2 to 6 y of age in China: a randomized, active-controlled, non-inferiority study

ABSTRACT

Meningococcal serogroups A and C cause significant numbers of cases in China. The Sanofi Pasteur meningococcal polysaccharide A + C vaccine (Men-AC) was licensed in China in 1995. Immunogenicity and safety of a single dose of Men-AC against a similar marketed vaccine, the Lanzhou Institute serogroups A and C vaccine (Lanzhou-AC), were evaluated in children 2 to 6 y of age. Antibody titers were determined before and on Day 30 after vaccination using a serum bactericidal assay using baby rabbit complement (SBA-BR). Immunogenicity endpoints included rates of seroconversion (postvaccination antibody titers ≥4-fold higher) and seroprotection (postvaccination titers ≥1:8). Unsolicited systemic adverse events (AEs) within 30 minutes after vaccination, solicited injection site and systemic reactions between Days 0 and 7, unsolicited non-serious AEs within 30 d, and serious adverse events (SAEs) throughout were recorded. Seroconversion rates against serogroups A and C were 97.0% (95% confidence interval [CI], 94.5–98.6) and 94.7% (95% CI, 91.6–97.0), respectively, in the Men-AC group and 97.7% (95% CI, 95.4–99.1) and 94.8% (95% CI, 91.7–97.0), respectively, in the Lanzhou-AC group, while seroprotection rates were 98.0% (95% CI, 95.8–99.3) and 97.0% (95% CI, 94.5–98.6), respectively, in the Men-AC group and 99.0% (95% CI, 97.2–99.8) and 96.8% (95% CI, 94.1–98.4), respectively, in the Lanzhou-AC group. Non-inferiority of Men-AC with regard to immunogenicity was demonstrated since the lower bounds of the 95% CIs of the differences in rates between the two groups were > −5% for both serogroups. Both vaccines were well tolerated.

KEYWORDS:

• Meningococcal Polysaccharide Vaccine
• meningococcal Serogroup A
• meningococcal Serogroup C
• safety
• immunogenicity
• China

Acknowledgments

We thank Bret Wing, PhD and Robert A. Lersch, PhD of Sanofi Pasteur Inc., Swiftwater, Pennsylvania, USA for managing the development of the manuscript. Prasad Kulkarni, PhD, CMPP of Asclepius Medical Communications LLC, Ridgewood, New Jersey, USA and Julia R. Gage, PhD of Gage Medical Writing LLC, Moorpark, California, USA assisted in the development of the manuscript with funding provided by Sanofi Pasteur SA, Lyon, France.

Disclosure of potential conflicts of interest

Drs. Zhu, Hu, and Li have no conflicts of interest to disclose. Drs. Shu and Oster are employees of Sanofi Pasteur and have no conflicts to disclose outside the submitted work.

Additional information

Funding

This study was funded by Sanofi Pasteur China, Beijing, China.