NCT06482216

Correlation of Protection Against Varicella in an Exploratory Study

• Status: Not Yet Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 400 (estimated)
• Sponsor: Sinovac (Dalian) Vaccine Technology Co., Ltd. · Industry
• Sex: All
• Age: 1 Year – 12 Years
• Healthy volunteers: Accepted

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

Interventions

Type	Name	Description
BIOLOGICAL	Varicella vaccine	lyophilized powder,subcutaneous injection

Timeline

• Start date: 2025-10-10
• Primary completion: 2027-05-10
• Completion: 2028-10-10
• First posted: 2024-07-01
• Last updated: 2025-01-27