This is a multi-center, blinded, randomized and Gardasil-controlled (quadrivalent HPV vaccine GARDASIL®) Phase III clinical study. The study will recruit a total of approximately 12,000 healthy Chinese women ages 20-45 years with permanent residence, who will be randomized at a 1: 1 ratio to receive the investigational vaccine or the positive control (quadrivalent HPV vaccine GARDASIL®), respectively.~Healthy women ages 20-45 eligible for the study will be stratified at a 2: 2: 1 ratio into three age subgroups (i.e. 20-26 years of age, 27-35 years of age and 36-45 years of age), and each subgroup will be randomized at a 1: 1 ratio to receive the investigational vaccine or the positive control (quadrivalent HPV vaccine GARDASIL®), respectively. A total of 1,000 subjects will be allocated to an Immunogenicity Cohort, who will also be randomized at a 1: 1 ratio to receive the investigational vaccine or the positive control. The Immunogenicity Cohort is set up to evaluate the immune responses induced by the investigational vaccine and their persistence.~For the Sample allocation plan, twelve thousand (12,000) subjects from the chosen clinical trial sites are stratified at a 2: 2: 1 ratio into 3 age subgroups, i.e. 4,800 in the subgroup of ages 20-26 years, 4,800 in the subgroup of ages 27-35 years, and 2,400 in the subgroup 36-45 years of age.~Immunogenicity evaluation will be conducted at a clinical trial site in 1,000 subjects, selected randomly in the order of enrollment.~The Primary study objectives also involve:~-To demonstrate that administration of the investigational vaccine reduces the Combined Incidence of HPV types 6/11/16/18/31/33/45/52/58-related persistent infections, and cervical, vulvar, vaginal and anal lesions detected in samples from three or more consecutive visits (+/-1 month visit window) 12 months or longer apart.~The Secondary study objectives involve:~To evaluate the safety profile of the investigational vaccine in healthy women ages 20-45;~To demonstrate that geometric mean titers of antibody responses specific to HPV types 6/11/16/18 induced by the investigational vaccine are non-inferior to those generated by GARDASIL;~To demonstrate that the investigational vaccine produces antibody responses specific to HPV types 31/33/45/52/58;~To evaluate the levels and persistence of antibody responses against HPV types 6/11/16/18/31/33/45/52/58 generated by the investigational vaccine;~To demonstrate that the investigational vaccine reduces the Combined Incidence of HPV types 6/11/16/18/31/33/45/52/58-related persistent infections detected in samples from 2 or more consecutive visits 6 months (+/-1 month visit window) or longer apart.~The Exploratory study objectives involve:~To evaluate the impact of a 3-dose regimen of the investigational vaccine on the incidence of HPV types 6/11/16/18/31/33/45/52/58-related cytological abnormalities (ASC-US, positive for high-risk HPV types, or worse) as determined by the Thinprep cytologic test (TCT test) among subjects, who are naïve (seronegative) to the relevant HPV type(s) (HPV 6/11/16/18/31/33/45/52/58) at baseline and remain negative to the relevant HPV type(s) as determined by HPV-DNA test and without abnormal cervical biopsy result through Month 7;~To evaluate the incidence of non-vaccine HPV type-related Cervical Intraepithelial Neoplasia (CIN), Adenocarcinoma in Situ (AIS) and Cervical Carcinoma as determined by histopathologic examination post 3 doses of the investigational vaccine;~To evaluate the incidence of non-vaccine HPV type-related persistent infections for no less than 6 months, and cervical, vulvar, vaginal and anal diseases as determined by histopathologic examination post 3 doses of the investigational vaccine;~To evaluate the incidence of non-vaccine HPV type-related cytological abnormalities (ASC-US, positive for high-risk HPV types, or worse) as determined by the TCT test post 3 doses of the investigational vaccine.
This study is to demonstrate that the administration of the investigational vaccine can reduce the Combined Incidence of HPV types 6/11/16/18/31/33/45/52/58-related high-grade Cervical Intraepithelial Neoplasia (CIN 2/3), Adenocarcinoma in Situ (AIS), Invasive Cervical Carcinoma, high-grade Vulvar Intraepithelial Neoplasia (VIN 2/3), high-grade Vaginal Intraepithelial Neoplasia (VaIN 2/3), high-grade Anal Intraepithelial Neoplasia (AIN 2/3), vulvar cancer, vaginal cancer or anal cancer.