Noninferiority of One HPV Vaccine Dose to Two Doses.

Emerging data suggest that a single dose may provide protection.

新兴数据表明，单剂次接种可能也能提供保护。

Whether a single dose of HPV vaccine would provide similar protection to two doses is uncertain.

尚不确定单剂HPV疫苗是否能提供与两剂疫苗相似的保护效果。

Methods

In this trial, we assessed whether one dose of an HPV vaccine was noninferior to two doses.

在这项试验中，我们评估了单剂HPV疫苗是否不劣于两剂疫苗。

Girls 12 to 16 years of age were randomly assigned, in a 1:1:1:1 ratio, to receive one or two doses of a bivalent HPV vaccine or one or two doses of a nonavalent HPV vaccine.

12至16岁的女孩按1:1:1:1的比例随机分配，接受双价或多价HPV疫苗的一剂或两剂接种。

The primary end point was new HPV type 16 or 18 infection occurring from month 12 to month 60 and persisting for at least 6 months.

主要终点是新发生的HPV 16型或18型感染，从第12个月至第60个月出现，并持续至少6个月。

The prespecified noninferiority margin was 1.25 infections per 100 participants.

预设的非劣效性边界是每100名参与者中感染1.25例。

We also assessed vaccine effectiveness by comparing HPV16 or HPV18 infection among the trial participants with that among girls and women enrolled in a nonrandomized survey.

我们还通过比较试验参与者与非随机调查中登记的女孩和女性的HPV16或HPV18感染情况来评估疫苗的有效性。

Results

A total of 20,330 participants were enrolled and underwent randomization, and 3005 unvaccinated participants were enrolled in the survey.

共有20,330名参与者被纳入并进行了随机分组，其中3005名未接种疫苗的参与者被纳入调查。

The noninferiority analysis showed that one vaccine dose was noninferior to two doses in preventing HPV16 or HPV18 infection.

非劣效性分析显示，一剂疫苗在预防HPV16或HPV18感染方面不劣于两剂。

The rate difference between one and two doses of the bivalent vaccine was -0.13 infections per 100 participants (95% confidence interval[CI], -0.45 to 0.15; P<0.001 for noninferiority), and the difference between one and two doses of the nonavalent vaccine was 0.21 infections per 100 participants (95% CI, -0.09 to 0.51; P<0.001 for noninferiority).

双价疫苗一剂与两剂之间的感染率差异为每100名参与者-0.13例（95%置信区间[CI]，-0.45至0.15；P<0.001，显示非劣效性），九价疫苗一剂与两剂之间的感染率差异为每100名参与者0.21例（95% CI，-0.09至0.51；P<0.001，显示非劣效性）。

The vaccine effectiveness was at least 97% in each of the four trial groups.

在四个试验组中，疫苗的有效性至少为97%。

No safety concerns were identified.

未发现任何安全问题。

Conclusions

One dose of either a bivalent or nonavalent HPV vaccine provided protection against HPV16 or HPV18 infection and was not inferior to two doses.

一次剂量的双价或九价HPV疫苗对HPV16或HPV18感染提供了保护，并且不劣于两剂次。

(Funded by the National Cancer Institute and others; ESCUDDO ClinicalTrials.gov number, NCT03180034.).

(由国家癌症研究所和其他机构资助; ESCUDDO ClinicalTrials.gov编号, NCT03180034.)