Primary analyses of a study in young women aged 16-26 years showed efficacy of the
nine-valent human papillomavirus (9vHPV; HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58)
vaccine against infections and disease related to HPV 31, 33, 45, 52, and 58, and
non-inferior HPV 6, 11, 16, and 18 antibody responses when compared with quadrivalent
HPV (qHPV; HPV 6, 11, 16, and 18) vaccine. We aimed to report efficacy of the 9vHPV
vaccine for up to 6 years following first administration and antibody responses over
5 years.