Yangjiang

Researchers are evaluating the immune persistence of the quadrivalent HPV vaccine in healthy Chinese females aged 9 to 45 years. This observational study focuses on women who have completed the vaccination schedule and aims to understand how well the immune response lasts over time. The study is sponsored by Shanghai Bovax Biotechnology Co., Ltd. and targets protection against HPV types 6, 11, 16, and 18, which are linked to HPV infections and related conditions such as cervical and vaginal cancers, genital warts, and precancerous cervical lesions. Participants in this study are those who previously completed three doses of the quadrivalent HPV vaccine following the 0, 2, and 6 months immunization schedule in prior clinical trials at specific centers in China. The study does not involve new vaccinations but monitors participants who provided blood samples at month 7 after vaccination. The research observes immune markers such as seroconversion rates and geometric mean titers for each HPV type in the vaccine at multiple time points up to 60 months. During the study, participants will undergo regular follow-ups to provide additional blood samples and undergo immune response assessments at months 12, 24, 36, 48, and 60. The primary outcomes measured include the seroconversion rate and antibody levels for each HPV strain in the vaccine over time. Participants must be willing and able to comply with study procedures and follow-up visits, ensuring ongoing monitoring of the vaccines immune persistence over a five-year period.