Study on Antibody Persistence and Immune Memory of Inactivated COVID-19 Vaccine

Centers for Disease Control and Prevention, China (Other)
Overall Status
Completed ID
Actual Duration (Months)
Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The study describe 1 year durability of humoral and cellular immune responses in 150 individuals who received COVID-19 inactivated vaccine. all participants were recruited aged between 18 and 59 years old. Every participant was familiarized with the aim of the study and asked to sign an informed consent agreement, and be required blood sampling at the day 0 of first dose vaccine and 1 month, 3 months, 6 months and 12 months after fully vaccination separately. From every sample, 10 ml, 10 ml, and 5 ml were dispensed in three vacuum blood collection tubes. Peripheral blood lymphocytes cell (PBMC) were isolated with the two 10 ml samples contained heparin to detect immune memory cells and cytokines. RBD-IgG and neutralizing antibody be detected by 5ml sample from separating gel vacuum tubes. every individual conducted a detailed analysis comparing neutralizing antibody, TEM, TCM , and report on the cellular and humoral immunity 1 year after accept COVID-19 vaccine.

Condition or DiseaseIntervention/TreatmentPhase

    Study Design

    Study Type:
    Actual Enrollment :
    150 participants
    Observational Model:
    Time Perspective:
    Official Title:
    A Prospective Cohort Study on Antibody Persistence and Immune Memory After Two Doses of Inactivated COVID-19 Vaccine in 150 People
    Actual Study Start Date :
    Jul 20, 2020
    Actual Primary Completion Date :
    Aug 30, 2021
    Actual Study Completion Date :
    Sep 27, 2021

    Outcome Measures

    Primary Outcome Measures

    1. Durability of humoral and cellular immune responses [12 months after fully vaccination]

      The humoral immunogenicity outcomes include the RBD-specific IgG titers and neutralising antibodies amounts at 1, 3, 6, and 12 months after the second shot. The positive cutoff for RBD-specific IgG antibodies was defined as the sample cutoff (S/CO) value ≥1.0. Seroconversion of neutralising antibodies was defined as a change from seronegative at baseline to seropositive or a four-fold titre increase. The positive cutoff of the titre for neutralising antibodies was 1/4. The cellular immune response outcomes measured by ICS assays across the blood collection time points.the percentage of RBD-specific CD4+ CD8+ memory T cells after vaccination.

    Secondary Outcome Measures

    1. The dynamic variation of the level of antibody [1,3,6 , 12 month]

      RBD-IgG and neutralizing antibody level after vaccination at 1,3 and 6 ,12months vaccination.

    2. Cytokine secretion by peripheral blood mononuclear cells [1,3,6,12 month]

      To study the cytokine production of PBMC after stimulation with RBD after vaccination at 1,3,6 and 12 months vaccination,for examples IL-2,IL-5,IFN and GrB.

    3. TCM and TEM amount varies at different time points [1,3,6,12 month]

      The dynamic variation of specificity TCM and TEM after vaccination at 1,3,6 and 12 months vaccination.

    Eligibility Criteria


    Ages Eligible for Study:
    18 Years to 59 Years
    Sexes Eligible for Study:
    Accepts Healthy Volunteers:
    Inclusion Criteria:
    • Working at the CDC

    • Between the ages of 18 and 59

    • Healthy

    • Not vaccinated with COVID-19 vaccine

    • Agreed to take a blood sample

    Exclusion Criteria:
    • who cannot take the COVID-19 vaccine due to some personal reasons

    • history of SARS-CoV, SARS-CoV-2, or Middle East respiratory syndrome infection

    • high-risk epidemiology history within 14 days before enrolment (eg, travel or residence history in communities with case reports, or contact history with someone infected with SARS-CoV-2)

    • axillary temperature of more than 37·0℃

    • history of allergy to any vaccine component.

    Contacts and Locations


    SiteCityStateCountryPostal Code
    1Beijing Center for Disease Control and PreventionBeijingChina

    Sponsors and Collaborators

    • Centers for Disease Control and Prevention, China


    None specified.

    Study Documents (Full-Text)

    None provided.

    More Information


    None provided.
    Responsible Party:
    Wu Jiang, Director of Institute for Vaccines and Immunization, Centers for Disease Control and Prevention, China Identifier:
    Other Study ID Numbers:
    • BJCDCWJ202101
    First Posted:
    Oct 11, 2021
    Last Update Posted:
    Oct 11, 2021
    Last Verified:
    Oct 1, 2021
    Studies a U.S. FDA-regulated Drug Product:
    Studies a U.S. FDA-regulated Device Product:
    Keywords provided by Wu Jiang, Director of Institute for Vaccines and Immunization, Centers for Disease Control and Prevention, China
    Additional relevant MeSH terms:

    Study Results

    No Results Posted as of Oct 11, 2021