Optimal Timing of Zoster Vaccine After Zoster Illness

Study Overview
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Brief Summary
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The purpose of this study is to determine the optimal timing of zoster vaccination to induce both higher cell-mediated immunity and humoral immunity in adult patients aged over 50 with history of zoster within 5 years.

Detailed Description
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Zoster vaccination is recommended by FDA for adults aged 60 years or older, and is approved for people aged 50 through 59 years old. For patients who had shingles, there is no specific length of time they must wait before receiving shingles vaccine. It is generally recommended that patients should wait for 6 to 12 months after recovery. The investigators plan to make scientific recommendation for optimal timing of zoster vaccine after zoster illness by comparing immune response between two groups (vaccination at 6 months to 2 years after shingles vs. 2 to 5 years after shingles). Primary outcome is ELISPOT response at week 6 after vaccination. Secondary outcome is gpELISA titer at week 6 after vaccination. All the patients will be asked if they have any contraindications for zoster vaccine by a physician before vaccination. And they will be monitored for any adverse reaction of the vaccination after 6 weeks (visiting the hospital).

Official Title
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Comparison of Immune Response Induced by Zoster Vaccine According to the Timing of Vaccination After Zoster Illness

Conditions
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Shingles

Intervention / Treatment
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* Biological: Zostavax


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults aged 50 years or older who have had shingles in 5 years Adults who did not receive zoster vaccination yet Adults who can understand and agreed with the informed consents. Exclusion Criteria: Adults who have conditions which is contraindication for zoster vaccine Adults who had zoster vaccination already Adults who take immunosuppressants Human Immunodeficiency Virus (HIV) patients whose CD4 T cell counts below 500/mm3 Adults with autoimmune disease who are anticipated to have a problem with immunogenicity for vaccine Adults who had organ transplantation and receive immunosuppressants Adults who are suspected to have active infectious disease Adults who are not eligible for zoster vaccination by investigator's assessment

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 6months to 2years after shingles<br>Patients will be vaccinated with Zostavax from 6 months to 2 years after zoster illness. | Biological: Zostavax<br>* Zostavax will be administrated by subcutaneous injection.<br>|
| Active Comparator: 2years to 5years after shingles<br>Patients will be vaccinated with Zostavax from 2 years to 5 years after zoster illness. | Biological: Zostavax<br>* Zostavax will be administrated by subcutaneous injection.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Varicella-zoster virus-specific interferon-gamma ELISPOT response | Investigators measure the number of SFC (spot forming cells) using interferon-gamma ELISPOT (enzyme-linked immunospot) assay at both right before vaccination and week 6 after vaccination and see the change between two values. | before Zostavax vaccination and at week 6 after vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Antibody titer against glycoprotein of varicella-zoster virus | Investigators measure the titer of VZV-specific glycoprotein-based enzyme-linked immunosorbent assay at both right before vaccination and week 6 after vaccination and see the fold change between two values. | before Zostavax vaccination and at week 6 after vaccination | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Herpes zoster vaccine, cell-mediated immunity