Last updated: 04/01/2026 08:40:16

Study to Assess the Association Between Recombinant Zoster Vaccine (RZV) and the Reduction of Dementia in Adults ≥65 Years of Age in the United States (US)

GSK study ID
222436
See study documents
Clinicaltrials.gov ID
Not applicable
EudraCT ID
Not applicable
EU CT Number
Not applicable
Trial status
Study complete
Study complete
Overview
Eligibility
Locations
Study documents
Results summary
Plain language summaries
Additional information

Trial overview

Official title: Assessing the Association Between Recombinant Zoster Vaccine (RZV) and the Reduction of Dementia in Adults ≥65 Years of Age in the US
Trial description: This study assessed the reduction of dementia and mild cognitive impairment (MCI) in individuals at Kaiser Permanente Southern California (KPSC) who received 2 doses of RZV (“vaccinated”) compared to individuals who did not receive RZV (“RZV unvaccinated”).
Primary purpose:
Not applicable
Trial design:
Not applicable
Masking:
Not applicable
Allocation:
Not applicable
Primary outcomes:

Incidence rates and hazard ratios (HRs) of dementia in the 2-dose RZV vaccinated and matched unvaccinated groups

Timeframe: From 6 months after the index date (receipt of RZV Dose 2) until the end of the follow-up period (31 December 2023), death, receipt of a dose of herpes zoster (HZ) vaccine, termination of KPSC membership, or occurrence of dementia, whichever comes first

Secondary outcomes:

Incidence rates and HRs of dementia in the 2-dose RZV vaccinated and matched unvaccinated groups stratified by MCI (mild cognitive impairment) status, ZVL status, sex, race/ethnicity, or age at index date

Timeframe: From 6 months after the index date (receipt of RZV Dose 2) until the end of the follow-up period (31 December 2023), death, receipt of a dose of HZ vaccine, termination of KPSC membership, or occurrence of dementia, whichever comes first

Incidence rates and HRs of MCI stratified by follow-up time in the 2-dose RZV vaccinated and matched unvaccinated groups

Timeframe: From 6 months after the index date (receipt of RZV Dose 2) until the end of the follow-up period (31 December 2023), death, receipt of a dose of HZ vaccine, termination of KPSC membership, or occurrence of MCI, whichever comes first

Incidence rates and HRs of Alzheimer’s disease in the 2-dose RZV vaccinated and matched unvaccinated groups

Timeframe: From 6 months after the index date (receipt of RZV Dose 2) until the end of the follow-up period (31 December 2023), death, receipt of a dose of HZ vaccine, termination of KPSC membership, or occurrence of Alzheimer’s disease, whichever comes first

Baseline characteristics of individuals in the 2-dose RZV vaccinated and matched unvaccinated groups

Timeframe: During the baseline period specific to each baseline variable

Interventions:
Not applicable
Enrollment:
Not applicable
Primary completion date:
2025-04-04
Observational study model:
Not applicable
Time perspective:
Not applicable
Clinical publications:
Not applicable
Medical condition
Herpes Zoster
Product
Not applicable
Collaborators
Kaiser Permanente Southern California
Study date(s)
May 2024 to April 2025
Type
Observational
Phase
Not applicable

Participation criteria

Sex
Female & Male
Age
65+ years
Accepts healthy volunteers
Yes
  • Individuals will be eligible for inclusion in the study if the following criteria are met:
  • Aged 65 years or older at the index date for all study objectives.
  • Certain individuals will be excluded from the study, including those with:
  • Any dementia diagnosis by ICD-10 code or prescription of medications used to treat symptoms of dementia by NDC code or exact match of the medication generic name prior to or on the index date or within 6 months following the index date, using all available history starting October 2015. Cases within 6 months following the index date are prevalent cases existing prior to vaccination.
Inclusion and exclusion criteria
Inclusion criteria:

    Individuals will be eligible for inclusion in the study if the following criteria are met:

    • Aged 65 years or older at the index date for all study objectives.
    • At least 1 year of continuous KPSC membership before the index date (allowing for a 31-day gap in membership) and until 6 months after the index date.
Exclusion criteria:

    Certain individuals will be excluded from the study, including those with:

    • Any dementia diagnosis by ICD-10 code or prescription of medications used to treat symptoms of dementia by NDC code or exact match of the medication generic name prior to or on the index date or within 6 months following the index date, using all available history starting October 2015. Cases within 6 months following the index date are prevalent cases existing prior to vaccination.
    • Receipt of RZV within 6 months following the index date. This is the 6-month period between the index date and first accrual of follow-up time.
    • Receipt of ZVL on or within 6 months following the index date. This is the 6-month period between the index date and first accrual of follow-up time.
    • Receipt of second dose of RZV less than 4 weeks after the first dose, since Advisory Committee on Immunization Practices (ACIP) guidelines state that these individuals must repeat the second dose.
    • Death within 6 months following the index date. This is the 6-month period between the index date and first accrual of follow-up time.

Trial location(s)

This study does not involve prospective enrollment of participants.

Study documents

Protocol
Available language(s): English
Download document(s)
Scientific result summary
Available language(s): English
Download document(s)

If you wish to request for full study report, please contact - [email protected]

Results overview

Refer to study documents

Recruitment status
Study complete
Actual primary completion date
2025-04-04
Actual study completion date
2025-04-04

Plain language summaries

Not applicable. GSK’s transparency policy provides for Plain Language Summaries for Interventional studies.

Additional information about the trial

Not applicable
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