Correlation of Protection Against Varicella in an Exploratory Study

Обзор

This study consists of two parts. Part 1 is a retrospective cohort study and part 2 is a prospective cohort study. In Part 1 ,the scaled logit model was used to assess the correlation between varicella-zoster virus (VZV) antibody titers using fluorescent-antibody-to-membrane-antigen assay (FAMA) 30 days after varicella vaccine immunization and the risk of subsequent varicella breakout/disease , to determine the protective threshold for achieving FAMA antibodies. Part 2 was to validate the model in part 1.

Подробное описание

Part 1 was based on a previous Phase Ⅲ, randomized, placebo-controlled clinical trial (NCT02981836) conducted from 2016 to 2017. The analysis data of part 1 was from historical serum, historical varicella cases and additional one year case monitoring conducted as an extension of the Phase III study.

Part 2 was conducted based on close contacts of varicella cases. All close contacts without varicella symptoms will be recruited and followed up for 14 days to monitor the occurrence of the varicella cases. Part 2 aimed to compare the differences of FAMA antibody titers in varicella breakthrough cases, non-breakthrough cases, and non-cases at the time of exposure to validate/calibrate the model established in part 1.

Вмешательства

• Биопрепарат Varicella vaccine
  lyophilized powder,subcutaneous injection

Первичные конечные точки

• Retrospective cohort: Varicella confirmed case [Срок оценки: one year after enrollment]
• Retrospective cohort: Varicella antibody titer [Срок оценки: on Day 30 after vaccination]
• Prospective cohort: Varicella confirmed case [Срок оценки: Within 14 days after enrollment]
• Prospective cohort: Varicella antibody titer [Срок оценки: Enrollment]

Вторичные конечные точки (2)

• Prospective cohort: Varicella antibody titer [Срок оценки: Within 3 days after eruption]
• Prospective cohort: Varicella antibody titer [Срок оценки: Within 14-21 days after eruption]

Критерии участия

Критерии включения

• 1-12 years children who were the siblings or children of the indicator varicella cases, or the deskmates/roommates of the indicator varicella cases;
• Having close contacts with the indicator varicella cases at least 2 days during the period from 5 days before the onset and 2 days after the onset;
• Without varicella vaccination history or having varicella vaccination history (the last dose of varicella was manufacured by Sinovac, with an interval of >30 days before enrollment)
• Subjects/legal guardian can understand and sign the informed consent;
• Being able to provide legal proof of identity.

Критерии исключения

• Without varicella history;
• Body temperature ≥37.0℃ on the day of enrollment, or skin rash on the head, torso, and limbs;
• Having any confirmed or suspected immunodeficiency disorder, including tumor patients undergoing chemotherapy, human immunodeficiency virus (HIV) infection, continuous use of steroid hormones for more than 30 days (prednisone equivalent ≥2mg/kg days in children), or having other immunosuppressive disorder as determined by the clinician;
• The investigators considered that participation in this study was not appropriate for various other reasons.

Критерии приведены из реестра в оригинале (на английском). Окончательную оценку соответствия проводит исследовательский центр.

Здоровые добровольцы: Да

Дизайн исследования

Модель наблюдения

Когортное

Центры проведения

Список центров уточняется — проверьте первичный протокол.

Идентификаторы

NCT: NCT06482216 · PRO-VZV-4007

Первоисточники (государственные реестры)

• ClinicalTrials.gov (NIH, США)

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