Background: The 9-valent human papillomavirus (9vHPV; HPV6/11/16/18/31/33/45/52/58) vaccine was approved for use in Chinese women aged 16-26 years in 2018. This phase 3, open-label study (NCT03903562) compared 9vHPV vaccine immunogenicity and safety in Chinese females aged 9-19 years and 27-45 years with Chinese females aged 20-26 years; we report results from day 1 through 1 month post-Dose 3. The study will continue through 54 months post-Dose 3 to assess antibody persistence in Chinese girls aged 9-19 years.
Methods: Participants aged 9-45 years received three doses of the 9vHPV vaccine. Geometric mean titers (GMTs) and seroconversion percentages for anti-HPV6/11/16/18/31/33/45/52/58 antibodies were determined by competitive Luminex immunoassay in serum samples obtained at day 1 and 1 month post-Dose 3. Adverse events (AEs) within 30 days post-vaccination and serious AEs (SAEs) occurring at any time were recorded.
Results: In total, 1990 participants (690 aged 9-19 years; 650 aged 20-26 years; 650 aged 27-45 years) were enrolled. At 1 month post-Dose 3, >99% of participants in the per-protocol immunogenicity population seroconverted to each vaccine HPV type. Anti-HPV6/11/16/18/31/33/45/52/58 antibody GMTs in the 9-19-year age group were non-inferior to those in participants aged 20-26 years. Anti-HPV6/11/16/18/31/33/45/52/58 seroconversion percentages in the 27-45-year age group were non-inferior to those in participants aged 20-26 years. Injection-site and systemic AEs were reported by 43.3% and 50.9%, 50.5% and 57.1%, and 43.8% and 43.4% of participants aged 9-19, 20-26, and 27-45 years, respectively. There were no vaccine-related SAEs, discontinuations due to AEs, and deaths.
Conclusion: Antibody responses induced by 9vHPV vaccination in Chinese females aged 9-19 years and 27-45 years were non-inferior to those in Chinese females aged 20-26 years. The vaccine was generally well tolerated.
Clinicaltrials: gov Identifier: NCT03903562.
Keywords: 9-valent human papillomavirus vaccine; China; Immunobridging; Immunogenicity; Prophylaxis; Safety.
Copyright © 2022. Published by Elsevier Ltd.