The 9-valent human papillomavirus (HPV) vaccine protects against the same four HPV types as the quadrivalent HPV vaccine and five additional oncogenic types. The pivotal efficacy study of the 9-valent vaccine was controlled with the quadrivalent vaccine. Since the trial had no placebo group, a direct comparison with an unvaccinated population was not possible. Here, we present efficacy analyses comparing the 9-valent vaccine group with a historic placebo population.
Three international, randomized, double-blind studies were conducted using the same methodology. In the efficacy study of the 9-valent vaccine (Protocol V503-001; NCT00543543), 7106 and 7109 women received the 9-valent or quadrivalent vaccine, respectively. In the historic efficacy studies of the quadrivalent vaccine (FUTURE I [NCT00092521] and II [NCT00092534]), 8810 and 8812 women received the quadrivalent vaccine or placebo, respectively. Cervical cytologic testing was performed regularly. Tissue samples from biopsy or definitive therapy (loop electrosurgical excision procedure, conization) were assessed for HPV DNA.
Among women negative to 14 HPV types prior to vaccination with the 9-valent vaccine, the incidence of high-grade cervical disease and cervical definitive therapy related to the nine HPV types was reduced by 97.4% (95% CI 91.0, 99.5) and 96.6% (95% CI 90.5, 99.1), respectively. The 9vHPV vaccine did not prevent disease related to HPV types detected at baseline but significantly reduced high-grade cervical disease related to other types.
Effective implementation of the 9-valent vaccine may substantially reduce the burden of cervical disease and related health care costs.