Safety and immunogenicity of a bivalent HPV16/18 vaccine in Chinese females
Li-Wei Shi, Juan Li, Bang-Wei Yu, Lirong Huang, Ke Li, Min Ji, Lingyun Zhou, Lin Yuan, Shuyuan Yang, Jingjing Chen, Ling Wang, Zhiwei Jiang, Rongcheng Li, Yanping Li, Jielai Xia, Zhaojun Mo, Changgui Li
Abstract
As global supply is still inadequate to address the worldwide requirements for HPV vaccines, we assessed the safety and immunogenicity of a new bivalent HPV16/18 vaccine. In this randomized, double-blind, placebo-controlled, phase 2 trial, healthy 9–45-year-old Chinese females in three age cohorts (600 aged 9–17 years; 240 aged 18–26 years; 360 aged 27–45 years) were randomized 1:1 to receive three doses (0,2,6 months) of HPV16/18 vaccine or placebo. We measured neutralizing antibodies against HPV 16 and 18 at 7 months and monitored safety to 12 months in all age cohorts; 9–17-year-old girls were monitored for safety and immunogenicity to 48 months. In vaccinees, 99.8% seroconverted for HPV 16 and 18 types at 7 months; respective GMTs of 5827 (95% CI: 5249, 6468) and 4223 (3785, 4713) were significantly (p < .001) higher than controls for all comparisons. GMTs in the 9–17-year-olds, which were significantly higher than in older women at 7 months, gradually declined to 48 months but remained higher than placebo with seropositivity rates maintained at 98.5% and 97.6% against HPV 16 and 18, respectively. Adverse events occurred at similar rates after vaccine and placebo (69.8% vs. 72.5%, p = .308), including solicited local reactions and systemic adverse events which were mainly mild-to-moderate. The bivalent HPV16/18 vaccine was well tolerated and induced high levels of neutralizing antibodies in all age groups which persisted at high levels to 48 months in the 9–17-year-old age group which would be the target for HPV vaccination campaigns.