NCT07354659

Brief Summary

Herpes zoster is caused by the reactivation of latent varicella-zoster virus (VZV) which stays in latency after its primary infection. Immunosenescence contributes significantly to elevating morbidity associated with aging. Vaccination plays a key role in reducing the disease burden of zoster and the associated complications. We are conducting a study entitled "A Randomized, Blinded, Placebo- and Active-Controlled, Adaptive Phase 2 Clinical Trial to Evaluate the Immunogenicity and Safety of SYS6017 (a Herpes Zoster mRNA Vaccine) in Healthy Participants Aged 40 Years and Above".

Trial Health

65
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
800

participants targeted

Target at P75+ for phase_2

Timeline
13mo left

Started Jan 2026

Shorter than P25 for phase_2

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress23%
Jan 2026May 2027

First Submitted

Initial submission to the registry

December 30, 2025

Completed
11 days until next milestone

Study Start

First participant enrolled

January 10, 2026

Completed
11 days until next milestone

First Posted

Study publicly available on registry

January 21, 2026

Completed
1.1 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 10, 2027

Expected
3 months until next milestone

Study Completion

Last participant's last visit for all outcomes

May 31, 2027

Last Updated

January 21, 2026

Status Verified

January 1, 2026

Enrollment Period

1.2 years

First QC Date

December 30, 2025

Last Update Submit

January 12, 2026

Conditions

Outcome Measures

Primary Outcomes (5)

  • solicited adverse events

    within 14 days post each vaccination

  • unsolicited adverse events

    within 30 days post each vaccination

  • Geometric Mean Concentration (GMC) of anti-gE antibody

    On Day 14 and Day 30 after the completion of the full vaccination course

  • Geometric Mean Fold Increase (GMFI) of anti-gE antibody

    On Day 14 and Day 30 after the completion of the full vaccination course

  • Seroconversion Rate (SCR) of anti-gE antibody

    On Day 14 and Day 30 after the completion of the full vaccination course

Secondary Outcomes (7)

  • serious adverse events

    from the first vaccination through 12 months post the second vaccination

  • adverse events of special interest

    from the first vaccination through 12 months post the second vaccination

  • pregnancy events reported by the participants

    from the first vaccination through 12 months post the second vaccination

  • Geometric Mean Titer (GMT) of anti-VZV antibody

    On Day 14 after the completion of the full vaccination course

  • Geometric Mean Fold Increase (GMFI) of anti-VZV antibody

    On Day 14 after the completion of the full vaccination course

  • +2 more secondary outcomes

Study Arms (7)

Dosage A of zoster mRNA vaccine SYS6017

EXPERIMENTAL
Biological: A zoster mRNA vaccine SYS6017

Dosage B of zoster mRNA vaccine SYS6017

EXPERIMENTAL
Biological: A zoster mRNA vaccine SYS6017

Dosage C of zoster mRNA vaccine SYS6017

EXPERIMENTAL
Biological: A zoster mRNA vaccine SYS6017

Dosage D of zoster mRNA vaccine SYS6017

EXPERIMENTAL
Biological: A zoster mRNA vaccine SYS6017

Dosage E of zoster mRNA vaccine SYS6017

EXPERIMENTAL
Biological: A zoster mRNA vaccine SYS6017

Placebo

PLACEBO COMPARATOR
Other: Placebo

Active Comparator Vaccine

ACTIVE COMPARATOR
Biological: Active Comparator Vaccine

Interventions

SYS6017,two-dose vaccination schedule (Month 0, 2)

Dosage A of zoster mRNA vaccine SYS6017Dosage B of zoster mRNA vaccine SYS6017Dosage C of zoster mRNA vaccine SYS6017Dosage D of zoster mRNA vaccine SYS6017Dosage E of zoster mRNA vaccine SYS6017
PlaceboOTHER

0.9% saline,two-dose vaccination schedule (Month 0, 2)

Placebo

Recombinant Zoster Vaccine (CHO cell),two-dose vaccination schedule (Month 0, 2)

Active Comparator Vaccine

Eligibility Criteria

Age40 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • \. Individuals aged 40 years or older;
  • \. Able to understand the study procedures, comply with the protocol requirements to attend all the scheduled visits, voluntarily consent to participate in the study, and sign the informed consent form;
  • \. Is physically eligible at the discretion of investigators based on medical history inquiry and physical examination; For participants with chronic underlying diseases (e.g., diabetes mellitus, hypertension, hyperlipidemia and other chronic conditions), they may be enrolled if their conditions have been well controlled within 3 months prior to enrollment in this study (i.e., additional medical interventions or major adjustments to treatments are not required);
  • \. For female participants of childbearing potential: No sexual activity or effective contraceptive methods were used within one menstrual cycle before enrollment; No pregnancy plans and agree to adopt effective contraceptive methods within 8 months after enrollment.

You may not qualify if:

  • \. History of zoster;
  • \. History of vaccination with varicella vaccine or zoster vaccine (including investigational vaccine);
  • \. Axillary temperature ≥ 37.1℃ on the day of enrollment or within 24 h before enrollment;
  • \. History of allergy to any component of the investigational vaccine; or history of severe allergic reactions to vaccines or medications (including but not limited to anaphylaxis, allergic laryngeal edema, Henoch-Schönlein purpura, thrombocytopenic purpura, or Arthus reaction);
  • \. History of myocarditis, pericarditis, or idiopathic cardiomyopathy, or any condition that could increases the risk of myocarditis or pericarditis
  • \. History of demyelinating diseases, including but not limited to Guillain-Barré syndrome, multiple sclerosis, ophthalmoneuromyelitis, acute disseminated encephalomyelitis, etc.;
  • \. Current epilepsy or convulsion, severe neurological or psychiatric disorders;
  • \. Have contraindications to intramuscular injection, e.g., diagnosed thrombocytopenia, any coagulation disorders, or ongoing treatment with anticoagulants, etc.;
  • \. Active malignant tumor, malignant tumor without adequate treatment, malignant tumor with a potential risk of recurrence during the study;
  • \. Active, unstable, severe or uncontrolled cardiovascular and cerebrovascular diseases, thrombotic diseases, blood and lymphatic system diseases, liver and kidney diseases, respiratory diseases, metabolic diseases, musculoskeletal diseases, autoimmune diseases, etc;
  • \. History of diagnosed immunocompromise or immunosuppression, congenital or functional asplenia, or splenectomy before enrollment;
  • \. Long-term (defined as more than 14 consecutive days) systemic use of immunosuppressants, immunostimulants, or other immunomodulatory drugs (e.g., corticosteroids at a dose of ≥ 20 mg/day prednisone or equivalent) within 6 months prior to enrollment; however, inhaled and topical corticosteroids are permitted; or planned administration of the aforementioned agents during the study period;
  • \. Administration of whole blood, plasma, serum, immunoglobulin, or monoclonal antibodies within 3 months prior to enrollment, or planned administration of the aforementioned products during the study period;
  • \. Blood donation or blood loss ≥ 450 mL within one month before enrollment, or planning to donate blood during the study;
  • \. Vaccination with any other vaccines within 30 days prior to enrollment, or planned vaccination with any other vaccines within 30 days after the last dose of the study vaccine;
  • +3 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

MeSH Terms

Conditions

Herpes Zoster

Condition Hierarchy (Ancestors)

Varicella Zoster Virus InfectionHerpesviridae InfectionsDNA Virus InfectionsVirus DiseasesInfections

Central Study Contacts

Clinical Trials Information Group officer

CONTACT

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
PREVENTION
Intervention Model
PARALLEL
Model Details: Randomized, placebo or active-controlled, Masking
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

December 30, 2025

First Posted

January 21, 2026

Study Start

January 10, 2026

Primary Completion (Estimated)

March 10, 2027

Study Completion (Estimated)

May 31, 2027

Last Updated

January 21, 2026

Record last verified: 2026-01