Effect of Recombinant Varicella Zoster Virus Glycoprotein E Vaccine on Incident Dementia Diagnosis in Adults Aged ≥76 Years: A Phase IV Randomized Controlled Trial
- Trial ID
- 2025-524598-17-00
- Protocol
- 300889
- Sponsor
- GlaxoSmithKline Biologicals
Trial statistics
Diseases & Conditions
Objectives
The primary objective is to evaluate the effect of the recombinant zoster vaccine on the risk of incident dementia in adults aged 76 years or older compared to a placebo. The secondary objective is to assess the effect of the vaccine on the risk of an incident Alzheimer's disease diagnosis in this population. 5
Participants
The sponsor did not provide information regarding the total number of participants. The study population consists of healthy volunteers, including both males and females, aged 76 years or older. The investigation focuses on individuals at risk for incident dementia. Eligible participants are residents of Finland who are capable of complying with the study protocol. Written or witnessed informed consent is required prior to any study-specific procedures.
Plans and Procedures
This is a phase IV, randomized, placebo-controlled, observer-blind, pragmatic trial designed to evaluate the effect of the recombinant zoster vaccine on the risk of an incident dementia diagnosis. The study population consists of adults aged 76 years or older. Participants are assigned to receive either the Shingrix vaccine, administered via intramuscular use, or a placebo consisting of a sterile saline solution. The primary endpoint is the incident diagnosis of dementia following the administration of the first dose. A secondary endpoint is the incident diagnosis of Alzheimer's disease. The estimated duration of the study, including recruitment, extends from March 2026 to March 2037.
Treatment
The experimental treatment consists of Shingrix, a recombinant, adjuvanted herpes zoster vaccine provided as a suspension for injection. The active substance is recombinant varicella zoster virus glycoprotein E. Administration is performed via intramuscular use at a dose of 0.5 ml.
The control group receives a placebo consisting of a sterile saline solution (0.9% w/v solution of sodium chloride in water). This substance is supplied in 1.25 mL pre-filled glass syringes.
Efficacy
The efficacy of the recombinant zoster vaccine will be evaluated by assessing the risk of an incident dementia diagnosis following the administration of the first dose of the study product or placebo. The primary endpoint is the incidence of a dementia diagnosis.
The secondary endpoint consists of the incident diagnosis of Alzheimer's disease post-first dose of the vaccine or placebo.
Inclusion and Exclusion Criteria
Inclusion Criteria
- Participants are eligible to be included in the study only if ALL of the following criteria apply: 1. Citizens living permanently in Finland, who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., return for follow-up visits).
- Written or witnessed informed consent obtained from the participant prior to performance of any study-specific procedure.
- Age 76 years or older at the time of signing the informed consent.
Exclusion Criteria
- Participants will be excluded from the study if any of the following criteria apply: 1. History of vaccination against HZ
- History of dementia prior to enrolment, including confirmed cases or those under investigation. This includes: a) History of a confirmed clinical diagnosis of dementia prior to enrolment b) Prior or current use of medications intended to treat dementia c) Current or recent history of cognitive assessments for any memory deficit or suspected dementia before enrollment including investigations that are ongoing or were inconclusive (but not those for which dementia was conclusively ruled out); MCI on its own without any other information to indicate cognitive decline or dementia will not result in exclusion
- Severely immunocompromised individuals (i.e., those with haematological cancer or have had stem cell transplant or organ transplant)
- Concurrently participating in another clinical trial, in which the participant has been or will be exposed to an investigational product
- Known systemic hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccines used in the study or to a vaccine containing any of the same substances
- Living in a nursing facility
Trial Status by Country
| Country | Status | Start of Recruitment | Planned Patients |
|---|---|---|---|
 Finland | Recruiting | 31 Mar 2026 | 35000 |
Sites & Investigators
Investigational Products
Details about the medicinal products being studied in this clinical trial.
| Product Name | Role in Trial | Formulation | Administration | Max Daily Dose | Treatment Duration | EU MP Number |
|---|---|---|---|---|---|---|
The Placebo used for the clinical trial is a sterile saline solution (0.9% w/v solution of NaCl
in water) supplied in 1.25 mL pre-filled glass syringes. | Placebo | N/A | — | — | — | N/A |
Shingrix powder and suspension for suspension for injection Herpes zoster vaccinerecombinant, adjuvanted | Test | POWDER AND SUSPENSION FOR SUSPENSION FOR INJECTION | INTRAMUSCULAR USE | 0.5 | 6 | PRD5990658 |
Shingrix suspension for injection in pre filled syringe Herpes zoster vaccinerecombinant, adjuvanted | Test | SUSPENSION FOR INJECTION IN PRE FILLED SYRINGE | INTRAMUSCULAR INJECTION | 0.5 | 6 | PRD13311134 |