Post-Marketing Surveillance of Adverse Events for the Recombinant Zoster Vaccine Among the Population over 50 Years Old in Hangzhou, China.

OBJECTIVES

This study aimed to evaluate the safety profile of the recombinant zoster vaccine (RZV) after its marketing in China.

METHODS

We present a descriptive analysis and safety signal assessment of adverse events following immunization (AEFI) associated with RZV between September 2020 and December 2023. The descriptive data collected includes demographic characteristics and the classification of characteristics of AEFI cases, while vaccine safety signal assessment was evaluated using the reporting odds ratio (ROR).

RESULTS

In total, we documented 275 AEFI cases following RZV vaccination, with a reporting rate of 76.22/10,000 doses administered. Notably, only one case was classified as serious, and the reporting rates were significantly higher among females, individuals aged 50-59 years, and those residing in rural areas. Furthermore, the reporting rate for the first dose exceeded that for the second dose. Among the reported AEFI cases, 98.91% were attributed to vaccine product-related reactions, and 97.45% were initially reported by either the vaccine recipient or their guardians. The interval between vaccination and symptom onset was predominant within 3 d after vaccination. The disproportionality analysis identified five positive signals-fever (37.5-38.5 °C), injection site reactions greater than 5 cm, pain, Henoch Schönlein purpura (HSP), and swelling-which suggests a stronger association with the RZV than the expected threshold.

CONCLUSION

In summary, RZV demonstrated a favorable safety profile. However, continued monitoring and research on the long-term safety implications of RZV are needed.