Impact of age at vaccination and cervical HPV infection status on binding and neutralizing antibody titers at 10 years after receiving single or higher doses of quadrivalent HPV vaccine

ABSTRACT

Long-term follow-up of a cohort of unmarried girls who received one, two, or three doses of quadrivalent HPV vaccine, between 10 and 18 years of age, in an Indian multi-centric study allowed us to compare antibody responses between the younger and older age cohorts at 10-years post-vaccination, and study the impact of initiation of sexual activity and cervical HPV infections on antibody levels. Among the younger (10–14 years) recipients of a single dose, 97.7% and 98.2% had detectable binding antibody titers against HPV 16 and HPV 18 respectively at ten years post-vaccination. The proportions among those receiving a single dose at age 15–18 years were 92.3% and 94.2% against HPV 16 and HPV 18 respectively. Mean HPV 16 binding antibody titers were 2.1 folds (95%CI 1.4 to 3.3) higher in those vaccinated at ages 10–14 years, and 1.9 folds (95%CI 1.2 to 3.0) higher in those vaccinated at 15–18 years compared to mean titers seen in the unvaccinated women. Compared to previous timepoints of 36 or 48 months, binding antibodies against HPV 16 and neutralizing antibodies against both HPV 16 and HPV 18 were significantly higher at 10 years. This rise was more pronounced in participants vaccinated at 15–18 years. No association of marital status or cervical HPV infections was observed with the rise in titer. Durability of antibody response in single dose recipients correlated well with the high efficacy of a single dose against persistent HPV 16/18 infections irrespective of age at vaccination, as we reported earlier.

KEYWORDS:

• Human papillomavirus
• HPV
• vaccine
• single dose
• age-stratified
• binding antibody
• neutralizing antibody

Acknowledgments

We are very grateful to the Bill & Melinda Gates Foundation for their generous financial port, Peter Dull and Carolyn Wendell (Integrated Clinical Vaccine Development, Bill & Melinda Gates Foundation) for their valuable support, encouragement, and scientific inputs; current and past members of the data safety monitoring board: Lynette Denny, John Schiller, Peter Sasieni, Thangarajan Rajkumar, Doreen Ramogola-Masire, Gina Ogilvy, Lutz Gissmann and Raul Murillo for their valuable advice and monitoring of the study safety and outcomes; We thank Ms Krittika Guinot, IARC, for help in preparation of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Disclaimer

Where authors are identified as personnel of the International Agency for Research on Cancer/World Health Organization, or the Centers for Disease Control and Prevention, the authors alone are responsible for the views expressed in this article and they do not necessarily represent the official position, decisions, policy or views of the International Agency for Research on Cancer/World Health Organization or the Centers for Disease Control and Prevention.

Supplementary data

Supplemental data for this article can be accessed on the publisher’s website at https://doi.org/10.1080/21645515.2023.2289242.

Additional information

Funding

The work was supported by the Bill & Melinda Gates Foundation [INV-032842].