Monitoring the safety of the adjuvanted human papillomavirus vaccine HPV-16/18-AS04 in association with pregnancy and potential immune-related diseases in China: A retrospective observational cohort study

Human papillomavirus (HPV) infection causes cervical cancer. The objective of the study is to monitor AS04-adjuvanted HPV-16/18 vaccine (Cervarix, GSK) safety in a real-world setting in China, using electronic health records from the Yinzhou Regional Health Information Platform (YRHIP). This retrospective observational cohort study included all permanent residents (males and females) aged 9–45 y with ≥12 months continuous YRHIP registration between 1 January 2010 and 31 December 2020. The study analyzed demographic information, diagnoses coded using International Classification of Diseases 10th Revision for potential immune-mediated diseases (pIMD) and pregnancy-related outcomes, and HPV vaccination records. Of 1,002,399 participants in the YRHIP, 891,463 met the eligibility criteria. In the age group 9–45 y, uptake of AS04-adjuvanted HPV-16/18 vaccine was 11.95/1000 persons. The incidence density for other spondylopathies, sarcoidosis, and pulmonary sarcoidosis was significantly higher in females vaccinated with any dose of AS04-adjuvanted HPV-16/18 vaccine compared with females who did not receive HPV vaccination during the study period (p < .01). No causal relationship could be established due to confounding factors and potential misclassification. The GSK safety database or EudraVigilance database were reviewed and no signals associated with these events were identified. For other pIMDs and adverse pregnancy-related outcomes, no increased incidence was found for vaccinated females. While certain pIMDs demonstrated an increased incidence in vaccinated individuals, no causal association was confirmed. Further research is needed to address residual confounding factors and validate findings. The overall safety profile of AS04-adjuvanted HPV-16/18 vaccination in Chinese girls and women aged 9–45 y could be considered as favorable.Clinical Trial Registration:Retrospectively registered on http://www.chinadrugtrials.org.cn/index.html, 22 March 2021, registration number CTR20210523.