Correlation of Protection Against Varicella in an Exploratory Study

NCT ID: NCT06482216

Last Updated: 2025-01-27

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Total Enrollment: 400 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2025-10-10
• Study Completion Date: 2028-10-10

Brief Summary

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.

Detailed Description

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.

Conditions

Varicella

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Vaccination group

The last dose of varicella vaccine given 30 days before enrollment was manufacture by Sinovac (Dalian) Vaccine Technology Co. LTD.,(Sinovac).

Varicella vaccine

Intervention Type: BIOLOGICAL

lyophilized powder,subcutaneous injection

Non-vaccination group

Without varicella vaccine history

No interventions assigned to this group

Interventions

Varicella vaccine

lyophilized powder,subcutaneous injection

Intervention Type: BIOLOGICAL

Eligibility Criteria

Inclusion Criteria

• 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.

Exclusion Criteria

• 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.

• Minimum Eligible Age: 1 Year
• Maximum Eligible Age: 12 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Sinovac (Dalian) Vaccine Technology Co., Ltd.

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Xiaoqiang Liu

Role: PRINCIPAL_INVESTIGATOR

Yunnan Provincial Center for Disease Control and Prevention

Zhiqiang Xie

Role: PRINCIPAL_INVESTIGATOR

Henan Provincial Center for Disease Control and Prevention

Central Contacts

Xiaoqiang Liu

Role: CONTACT

lxq7611@126.com

15911568282

Other Identifiers

PRO-VZV-4007

Identifier Type: -

Identifier Source: org_study_id