PRISMA AND EXTEND 2.0 FOLLOW-UP OF STUDY PARTICIPANTS

人乳头瘤病毒（HPV）感染是宫颈癌发生的必要条件。在全球范围内，HPV 16和18型感染约占宫颈癌病例的70%。如果在全球部署预防性HPV疫苗接种和宫颈癌筛查，并对宫颈癌前病变进行有效的诊断性随访和治疗，宫颈癌作为一个公共卫生问题几乎可以消除。然而，全球只有不到10%的年轻女孩接受HPV疫苗接种，接受宫颈癌筛查的妇女比例也同样低。因此，尽管2018年世卫组织呼吁消除宫颈癌作为一个公共卫生问题，但预计宫颈癌负担将在未来世纪增加。NCI继续推进HPV疫苗接种和筛查方面的宫颈癌预防研究。 Prisma PRISMA是一项随机对照临床试验，纳入5000名18-30岁的女性，以量化与未接种疫苗相比，单剂量二价和九价HPV疫苗提供的宫颈HPV 16/18持续性感染事件的减少，这是世界上大多数14岁以上女性的默认标准。 在2023财年，首次12个月随访访视的窗口打开，更新了研究表格和手册，并对工作人员进行了随访程序培训。 扩展2.0： 哥斯达黎加HPV疫苗试验（CVT）是一项以社区为基础的、许可前的随机临床试验，旨在评估基于VLP的二价HPV疫苗。一个更出乎意料和新颖的发现表明，在事后分析中，在CVT的盲期随访四年后，最初未感染这些类型的女性中，四年内对HPV 16/18感染的保护对于一个，两个或三个剂量的接受者来说都很高。在接受单次接种的女性中，HPV 16和HPV 18抗体滴度（通过ELISA评估）显著高于先前暴露于HPV 16/18的未接种疫苗的女性;滴度在接种后6至48个月保持稳定升高，尽管低于两次或三次接种的水平。我们最初将CVT延长至7年和9年;并进一步延长了991名14岁和16岁妇女的两次额外访问（EXTEND）。目前的研究，EXTEND2.0，是对693名18岁和20岁女性的两次访问。 我们的目的是通过剂量描述HPV疫苗接种后抗体反应的长期阳性率和稳定性。 在2023财年，18年随访访视的窗口打开。近60%符合条件的女性参加了访视，并对采血的依从性很高（100%）。

Human papillomavirus (HPV) infection is necessary for the development of cervical cancer. Worldwide, infection with HPV types 16 and 18 account for approximately 70% of cervical cancer cases. Cervical cancer could be nearly eliminated as a public health problem if prophylactic HPV vaccination and cervical cancer screening with effective diagnostic follow up and treatment of cervical precancers were deployed globally. Yet, less than 10% of young girls receive HPV vaccination and similarly low proportion of women receive cervical cancer screening globally. Consequently, cervical cancer burden is expected to increase over the coming century despite the 2018 WHO call for cervical cancer elimination as a public health problem. NCI continues to push forward cervical cancer prevention research on both HPV vaccination and screening. PRISMA PRISMA is a randomized, controlled clinical trial of 5000 women aged 18-30 years to quantitate the reduction in incident cervical HPV16/18 persistent infections afforded by a single dose of the bivalent and nonavalent HPV vaccines compared to no vaccination, the default standard in the majority of the world for women over the age of 14 years. In FY23, the window for the first 12-month follow-up visit opened, study forms and manuals were updated, and staff were trained in the follow-up procedures. EXTEND2.0: The Costa Rica HPV Vaccine Trial (CVT) was a community-based, pre-licensure, randomized clinical trial, to evaluate the VLP-based, bivalent HPV vaccine. One of the more unexpected and novel discoveries showed that, in a post-hoc analysis, protection over four years against HPV16/18 infections among women initially uninfected with these types was uniformly high for recipients of one, two, or three doses after four years of follow-up in the blinded phase of the CVT. Among women who received a single dose, HPV16 and HPV18 antibody titers (assessed by ELISA) were substantially higher than those among unvaccinated women previously exposed to HPV16/18; titers remained stably elevated from 6-to-48 months post-vaccination, albeit at lower levels than for two or three doses. We initially extended CVT to 7 and 9 years; and further extended the effort for two additional visits from 991 women at years 14 and 16 (EXTEND). The current study, EXTEND2.0, is for two more visits from 693 women at years 18 and 20. We aim to describe, by dose, the long-term positivity and stability of the antibody response to HPV vaccination. In FY23, the window for the 18-year follow-up visit opened. Nearly 60% of the eligible women attended the visit with high compliance with blood collection (100%).