Abstract
Protection against oncogenic non-vaccine types (cross-protection) offered by human papillomavirus (HPV) vaccines may provide a significant medical benefit. Available clinical efficacy data suggest the two licensed vaccines [HPV-16/18 vaccine, GlaxoSmithKline Biologicals (GSK), and HPV-6/11/16/18 vaccine, Merck and Co., Inc.,] differ in terms of protection against oncogenic non-vaccine HPV types -31/45. The immune responses induced by the two vaccines against these two non-vaccine HPV types (cross-reactivity) was compared in an observer-blind study up to Month 24 (18 mo postvaccination), in women HPV DNA-negative and seronegative prior to vaccination for the HPV type analyzed [HPV- 010 (NCT00423046)]. Geometric mean antibody titers (GMTs) measured by pseudovirion-based neutralization assay (PBNA) and enzyme-linked immunosorbent assay (ELISA ) were similar between vaccines for HPV-31/45. Seropositivity rates for HPV-31 were also similar between vaccines; however, there was a trend for higher seropositivity with the HPV-16/18 vaccine (13.0-16.7%) vs. the HPV-6/11/16/18 vaccine (0.0-5.0%) for HPV-45 with PBNA, but not ELISA . HPV-31/45 cross-reactive memory B-cell responses were comparable between vaccines. Circulating antigen-specific CD4+ T-cell frequencies were higher for the HPV-16/18 vaccine than the HPV-6/11/16/18 vaccine {HPV-31 [geometric mean ratio (GMR) = 2.0; p = 0.0002] and HPV-45 [GMR = 2.6; p = 0.0092]}, as were the proportion of T-cell responders (HPV-31, p = 0.0009; HPV-45, p = 0.0793). In conclusion, immune response to oncogenic non-vaccine HPV types -31/45 was generally similar for both vaccines with the exception of T-cell response which was higher with the HPV-16/18 vaccine. Considering the differences in cross-protective efficacy between the two vaccines, the results might provide insights into the underlying mechanism(s) of protection.
Original language | English (US) |
---|---|
Pages (from-to) | 1359-1373 |
Number of pages | 15 |
Journal | Human Vaccines |
Volume | 7 |
Issue number | 12 |
DOIs | |
State | Published - Dec 2011 |
Externally published | Yes |
Keywords
- Cervarix®
- Cervical cancer
- Cross-protection
- Gardasil®
- HPV-31
- HPV-45
- Human papillomavirus
- Immunogenicity
ASJC Scopus subject areas
- Immunology
- Pharmacology, Toxicology and Pharmaceutics(all)