Article
作者: Yu, Bang-Wei ; Li, Wei ; Huang, Li-Rong ; Chen, Jing-Jing ; Li, Ke ; Li, Juan ; Jiang, Zhi-Wei ; Li, Jian-Biao ; Shi, Li-Wei ; Li, Chang-Gui ; Qi, Yang-Yang ; Li, Yan-Ping ; Xia, Jie-Lai ; Dong, Yu-Lian ; Yang, Qing ; Mo, Zhao-Jun ; Yuan, Lin ; Ji, Min ; Li, Rong-Cheng ; Zhou, Ling-Yun ; Yan, Xue-Mei
BACKGROUND:We assessed the safety, immunogenicity and antibody persistence of two- and three-dose schedules of the novel bivalent HPV16/18 vaccine (HPV-2, Walrinvax) in the per-protocol target population of initially seronegative 9-14 year-old girls, including a non-inferiority comparison with the three-dose schedule in 18-26 year-old women.
METHODS:This randomized phase 3b trial in Guangxi Zhuang Autonomous Region, China, involved healthy Chinese females in two age cohorts; 600 girls aged 9-14 years and 300 women aged 18-26 years. Girls were randomly assigned (1:1) to receive either two (Months 0,6) or three (Months 0,2,6) intramuscular doses of HPV-2. All participants were monitored for immunogenicity as neutralizing antibodies up to 36 months. Primary objectives were non-inferiority analyses of immunogenicity between two- and three-dose girl groups and adult women at Month 7; safety assessments were based on participant-completed diary cards.
RESULTS:All groups demonstrated marked increases in neutralizing antibodies against HPV 16 and 18 that persisted above baseline to 36 months. Month 7 responses in both girl groups were non-inferior to those in the women and were statistically higher after two-doses than girls or women who received three doses. GMTs waned after month 7, but then maintained a plateau level until month 36. Vaccination was well tolerated in all groups with no serious adverse events reported.
CONCLUSIONS:Immune responses to two doses of HPV-2 vaccine in adolescent girls were non-inferior to those after three doses in young women, an age cohort in which clinical efficacy of HPV-2 against cervical cancer has been demonstrated.