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Not yet recruitingNCT06954818Updated May 8, 2025

Safety and Immunogenicity of SYS6017 in Healthy Participants Aged 40 Years or More

A Phase 1 interventional study of A zoster mRNA vaccine SYS6017 and Placebo in Herpes Zoster, sponsored by CSPC Megalith Biopharmaceutical Co.,Ltd.. Not yet recruiting. Open to participants aged 40 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-05-08.

Sponsored by CSPC Megalith Biopharmaceutical Co.,Ltd. (part of CSPC Pharmaceutical Group Limited) · Phase 1, Interventional, and Prevention

From the registry’s dates

  • Primary completion was expected by Dec 2025, 10 months ago, but the record still lists the study as not yet recruiting.
Phase
Phase 1
Study type
Interventional
Enrollment
200
Allocation
Randomized
Ages
40 Years and older
Sex
All
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Study 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. This randomized, observer-blind, placebo-controlled, adaptive phase 1 trial aims to evaluate the safety and immunogenicity of an investigational zoster mRNA vaccine in healthy participants aged 40 years or more.

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Conditions studied

  • Herpes Zoster

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03

In context

Herpes Zoster

370 studies on the registry are indexed under Herpes Zoster; 63 are open to participants now.

This study's planned enrollment of 200 is below the median of 242 across 306 interventional studies indexed under Herpes Zoster.

Browse Herpes Zoster studies →

Lead sponsor

CSPC Megalith Biopharmaceutical Co.,Ltd. is the lead sponsor of 38 studies on the registry; 37 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
40 Years and older
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • 1. Healthy participants aged 40 years or more;
  • 2. Be able to understand the study procedures and comply with the requirements of the protocol for the scheduled visits, voluntarily consent to participate in the study and sign the informed consent form (ICF);
  • 3. Being in good health at the discretion of investigators based on medical history inquiry, physical examination, laboratory test and electrocardiograph examination;
  • 4. For female participants of childbearing potential: no sexual activity or used effective contraceptive methods within one menstrual cycle before enrollment; no pregnancy plans and agree to used effective contraceptive methods with 8 months after enrollment.

Exclusion criteria

Exclusion Criteria:

  • 1. History of zoster;
  • 2. History of vaccination with varicella vaccine or zoster vaccine (including investigational vaccine);
  • 3. Axillary temperature ≥ 37.1℃ on the day of enrollment or within 24 h before enrollment;
  • 4. Have abnormal test or examination result that is of Grade 1 (inclusive) or more in accordance with the Guidelines for Adverse Event Grading Standards for Clinical Trials of Preventive Vaccines (2019) issued by China National Medical Products Administration or other applicable adverse event grading standards referred in the protocol;
  • 5. History of allergy to any component of the investigational vaccine, or history of severe allergic reaction (including but not limited to anaphylaxis, allergic laryngeal edema, Henoch-Schonlein purpura, thrombocytopenia purpura or Arthus reaction) to vaccines or medicines;
  • 6. History of myocarditis, pericarditis, or idiopathic cardiomyopathy, or any condition that would increase the risk of myocarditis or pericarditis;
  • 7. History of demyelinating diseases, including but not limited to Guillain-Barré syndrome, multiple sclerosis, ophthalmoneuromyelitis, acute disseminated encephalomyelitis, etc.
  • 8. Current epilepsy or convulsion, severe neurological or psychiatric disorders;
  • 9. Have contraindications to intramuscular injection, e.g., diagnosed thrombocytopenia, any coagulation disorders, or current treatment with anticoagulants, etc;
  • 10. Active malignant tumor, malignant tumor without adequate treatment, malignant tumor with a potential risk of recurrence during the study;
  • 11. 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;
  • 12. Have diagnosed immunocompromise or immunosuppression, congenital or functional asplenia, or splenectomy;
  • 13. Have received immunosuppressants, immunostimulants, or other immunomodulatory medicines (e.g., corticosteroids, ≥ 20 mg/d prednisone or equivalent) for a long time (defined as 14 days or more), within 6 months before enrollment, or planning to receive the aforementioned medicines during the study; inhaled and topical steroids are allowed;
  • 14. Have received whole blood, plasma, serum, immunoglobulins, or monoclonal antibodies within 3 months before enrollment, or planning to receive these products during the study;
  • 15. Blood donation or blood loss ≥ 450 mL within 1 month before enrollment, or planning to donate blood during the study;
  • 16. Have received any other vaccine within 30 days before enrollment, or planning to receive any other vaccine within 30 days after the last dose;
  • 17. Currently participating in or planning to participate in other clinical trials during the study;
  • 18. For female participant of childbearing potential: having positive urine pregnancy test, being in pregnancy or lactation before enrollment;
  • 19. Unable to comply with the study procedures or adhere to the study requirements, or there are other conditions that make the participation in this study inappropriate, as determined by the investigators.
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Study design

Phase
Phase 1
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Investigator, Outcomes assessor)
Enrollment
200 participants (estimated)

Study arms

  • Experimental
    Investigational vaccine of Dosage A

    Biological: A zoster mRNA vaccine SYS6017

  • Experimental
    Investigational vaccine of Dosage B

    Biological: A zoster mRNA vaccine SYS6017

  • Experimental
    Investigational vaccine of Dosage C

    Biological: A zoster mRNA vaccine SYS6017

  • Experimental
    Investigational vaccine of Dosage D

    Biological: A zoster mRNA vaccine SYS6017

  • Experimental
    Investigational vaccine of Dosage E

    Biological: A zoster mRNA vaccine SYS6017

  • Placebo comparator
    Placebo

    Other: Placebo

Interventions

  • BiologicalA zoster mRNA vaccine SYS6017

    SYS6017 is an investigational lipid nanoparticle (LNP)-coated mRNA vaccine encoding the glycoprotein E (gE) of VZV, and indicated for active immunization for the prevention of zoster caused by the reactivation of latent VZV.

  • OtherPlacebo

    saline solution

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What researchers measure

Primary outcomes

  1. solicited adverse events

    Time frame: within 14 days post each vaccination

  2. unsolicited adverse events

    Time frame: within 30 days post each vaccination

Secondary outcomes

  1. serious adverse events

    Time frame: from the first vaccination through 12 months post the second vaccination

  2. adverse events of special interest

    Time frame: from the first vaccination through 12 months post the second vaccination

  3. pregnancy events

    Time frame: from the first vaccination through 12 months post the second vaccination

  4. anti-gE antibody geometric mean concentration, geometric mean fold increase and seroconversion rate.

    Time frame: before the second vaccination, 14 and 30 days post the second vaccination

  5. anti-VZV antibody geometric mean titer, geometric mean fold increase and seroconversion rate.

    Time frame: before the second vaccination, 14 and 30 days post the second vaccination

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Study locations

No study locations are listed for this record.

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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 8, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT06954818
Responsible party
Sponsor
First posted
May 2, 2025
Start date
May 10, 2025 (estimated)
Primary completion
Dec 10, 2025 (estimated)
Completion
Nov 10, 2026 (estimated)
Last update
May 8, 2025

Study contacts

Clinical Trials Information Group officer
Contact
ctr-contact@cspc.cn
86-0311-69085587

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in May 2025. You cannot join it, but the record below documents what was studied.

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