Objective  To assess the efficacy, immunogenicity and safety of vaccination of 9-valent human papillomavirus (9vHPV) vaccine and to provide evidences for developing vaccination strategies for HPV vaccine in China.

  Methods  We retrieved studies on the efficacy, immunogenicity and safety of the mass vaccination of 9vHPV vaccine and quadrivalent HPV (qHPV) vaccine published till August 31, 2018 through China National Knowledge Infrastructure (CNKI), Wanfang Database, Chinese Sci-Tech Journals Database (VIP), Medline/PubMed, the Excerpta Medicadatabase (EMBASE), Cochrane Library, and the database of clinicaltrials.gov and conducted a meta-analysis using Stata 12.0.

  Results   Totally four randomized controlled trials (RCTs) involving 16 239 participants and one other survey were included in the meta-analysis. The protective effect of 9vHPV vaccine was stronger than that of qHPV vaccine on diseases related to HPV31, 33, 45, 52, and 58 infection but the protective effects of the two vaccines were not significantly different on diseases related to HPV 6, 11, 16, and 18 (P > 0.05 for all) among protocol populations (PPs). The results of intention to treat (ITT) analysis demonstrated that the incidence rates of diseases related to HPV31, 33, 45, 52, and 58 infection were lower among the participants without HPV infection before HPV vaccine inoculation than those among the controls, with the protection rates of 70.7% – 100%; while the incident rates were not significantly different between the two groups for the participants with HPV infection before HPV vaccine inoculation (P > 0.05). The positive rates of serum HPV31, 33, 45, 52, 58 antibody were significantly higher among the participants having 9vHPV vaccine inoculation than those among the participants having qHPV vaccine inoculation, with a pooled rate ratio (RR) of 8.43 (95% confidence interval 95% CI: 4.88 – 14.57); whereas there were no significant differences between the immunization effect of 9vHPV and qHPV vaccine inoculation on HPV 6, 11, 16, and 18 (P > 0.05 for all). A higher incidence rate of reaction at injection site was reported among the participants with 9vHPV vaccine than that among those with qHPV vaccine, with a pooled RR of 1.07 (95% CI: 1.05 – 1.08), while the incidence rates of systemic adverse events were not significantly different between the participants with the two vaccines. Even though the incidence rate of serious adverse events was higher among the participants with 9vHPV vaccine than that among those with qHPV vaccine, with a pooled RR of 1.27 (95% CI: 1.05 – 1.54), the confirmed vaccination-related serious adverse events were rare (< 0.1%) and of insignificant difference between the two groups of participants. Among the PPs, the protective effects of 9vHPV vaccine inoculation against major cervical, vulvar, and vaginal diseases related to HPV31, 33, 45, 52, and 58 infection were stronger than those of qHPV vaccine; but the protective effects of 9vHPV and qHPV vaccine inoculation against diseases related to HPV6, 11, 16, 18 infection were not significantly different (P > 0.05).

  Conclusion  The vaccination of 9vHPV vaccine is effective in prevention of cervical and genital disease associated with HPV infections of some genotypes.