Long-term Follow-up of Bivalent Human Papillomavirus (HPV) Vaccine Study in Women

This extension study aims to evaluate the long-term protection and immune response of the bivalent HPV vaccine in women aged 18-30 who participated in a previous efficacy study (311-HPV-1003). Participants will be monitored over two years, with two visits at 96 and 120 months after their initial vaccination. No additional vaccine doses will be given. Cervical samples will be obtained for ThinPrep Cytologic Testing (TCT) and HPV DNA typing. If applicable, participants meeting referral criteria for colposcopy will undergo the procedure during these visits, and tissue samples will be collected from those requiring a biopsy. Blood samples will be drawn from an immunology subset for antibody testing.The study includes data collection from multiple sites across China to assess the vaccine's long-term efficacy in preventing HPV-related cervical diseases and its durability over time.