A Nonrandomized, Non-double Blinded Prospective Cohort Study to Evaluate the Preventive Efficacy of Quadrivalent HPV6/11/16/18 Vaccine for the Persistent Infection of HPV16 Genotype or HPV18 Genotype in Japanese Women Aged 27-45 Years.

A series of evidence for HPV vaccines has demonstrated the efficacy in young women (Aged less than 26) across the globe. In contrast, limited evidence are available for the efficacy of the quadrivalent HPV6/11/16/18 vaccine in adult women (Aged 27+). Most importantly, evidence for Japanese adult women is not available to date. Nevertheless, , we hypothesize that the quadrivalent HPV6/11/16/18 vaccine demonstrate the efficacy also in Japanese adult women. The outcome from this trial will be the first local evidence, which brings a considerable impact in OB/GY academia where local evidence is weighed heavily compared with global evidence - serves as a strong basis to support catch up program of HPV vaccines for young adults. As a consequence, we believe this study will develop a local supportive evidence for prevention of HPV infection by an HPV vaccine in young adults, which results in substantial public health improvement through prevention of HPV infection in Japan where active recommendation is halted long time.