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A Study Evaluating the Safety and Immunogenicity of MVA Strain Monkeypox Attenuated Live Vaccine

A Randomized, Double-blind, Placebo-controlled Phase I Clinical Trial Evaluating the Safety and Immunogenicity of MVA Strain Monkeypox Attenuated Live Vaccine for Individuals Aged 18 and Above

Status
Recruiting
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06771479
Enrollment
120
Registered
2025-01-13
Start date
2025-01-22
Completion date
2026-05-30
Last updated
2025-10-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Monkeypox

Keywords

Monkeypox vaccine, safety, vaccine, immunogenicity, Monkeypox

Brief summary

This is a randomized, double blinded, controlled phase I clinical study. To evaluate the safety and immunogenicity of receiving two doses of MVA strain monkeypox attenuated live vaccine in individuals aged 18 years and above.

Detailed description

This is a randomized, double blinded, controlled phase I clinical study. The study plans to recruit 120 participants aged 18 years and above. The experimental vaccine MVA strain monkeypox attenuated live vaccine has two different doses (low dose and high dose). The ratio of low-dose experimental group, high-dose experimental group, and placebo group is 1:1:1. Participants will be divided into three groups: healthy individuals, men who have sex with men, and HIV infected individuals, with a ratio of 2:1:1. Different groups will be divided into individuals with a history of vaccination against smallpox and those without a history of immunization, based on whether each population has a history of vaccination against smallpox. Each participant will receive one dose of the experimental vaccine or placebo on day 0 and day 28, respectively.

Interventions

BIOLOGICALMVA strain monkeypox attenuated live vaccine (low dose)

Low dose MVA strain monkeypox attenuated live vaccine

BIOLOGICALMVA strain monkeypox attenuated live vaccine (high dose)

High dose MVA strain monkeypox attenuated live vaccine

OTHERPlacebo

Vaccine excipient

Sponsors

Shanghai Institute Of Biological Products
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* On the day of enrollment, individuals aged 18 years or older with a history of smallpox vaccination must have been born before 1980; * Can provide legal proof of identity; * Be able to understand the experimental procedure and sign a written informed consent form, expressing agreement to participate in the experiment; * Be able to participate in all planned follow-up visits and comply with all trial procedures (such as completing diary/contact cards and being able to return for visits); * On the day of enrollment, the body temperature was less than 37.3 ℃ (axillary temperature); * Men and women of childbearing age who have no plans to have children within 6 months and agree to take effective contraceptive measures within 6 months after receiving the experimental vaccine.

Exclusion criteria

* Individuals with a history of smallpox, monkeypox, or close contact with monkeypox in the past; * Individuals who are allergic to any ingredients of eggs, vaccines, or substances used in production processes, or have a history of other severe allergies; * Use immunoglobulin and/or any blood products within 3 months prior to administering the trial vaccine, or plan to use them during the trial period; * Currently using salicylate drugs or planning long-term use during the trial period; * Have used any experimental or unregistered products within one month prior to administering the trial vaccine, or plan to use them during the trial period; * Administer inactivated vaccine within 14 days before administering the experimental vaccine or attenuated live vaccine within 30 days before administering the experimental vaccine; * Chronic disease patients are in the acute or progressive phase of chronic disease; * Long term use of immunosuppressants or other immunomodulatory drugs within 6 months prior to vaccination with the experimental vaccine; * Having undergone chemotherapy or radiation therapy or organ and bone marrow transplantation related treatments for cancer or other diseases; * Diseases or medical measures that lead to immune dysfunction, such as congenital immunodeficiency, organ and bone marrow transplantation, leukemia, lymphoma, Hodgkin's disease, multiple myeloma or malignant tumors, etc; * Moderate or severe acute illness/infection, or febrile illness on the day of vaccination; * Individuals with a history of thrombocytopenia or other coagulation disorders may be contraindicated for subcutaneous injection; * Suffering from serious cardiovascular disease, serious liver and kidney disease, and diabetes that cannot be controlled by drugs; * Previous history of mental or neurological disorders or family history; * Currently suffering from various infectious, suppurative, and allergic skin diseases; * Women of childbearing age: pregnant or lactating, or with a positive blood pregnancy test; * Plan to move before the end of the trial or leave the local area for a long time during the scheduled trial visit; * Abnormal blood routine, blood biochemistry, urine routine, electrocardiogram or heart disease related indicators before vaccination (except for minor abnormalities judged by doctors to have no clinical significance); * Researchers believe that any situation that may affect the evaluation of the experiment; * Active tuberculosis patients; * For HIV infected individuals, the plasma HIV-1 RNA level during screening should be ≥ 200 copies/mL, or positive test for hepatitis B, hepatitis C and syphilis; * For healthy people and men and women who have sex with each other, hepatitis B, hepatitis C, syphilis and HIV) are positive; * Individuals who experience severe allergic reactions after the first dose of vaccination; * Serious adverse events that are definitely related to the first dose of vaccination; * For those who are newly discovered or occur after the first dose of vaccination and do not meet the inclusion criteria or the

Design outcomes

Primary

MeasureTime frameDescription
Immediate adverse events60 minutes after each dose of vaccinationThe occurrence of any adverse events within 60 minutes after each dose of vaccine immunization.
Solicited Adverse Events14 days after each dose of vaccinationAdverse events defined by the protocol that occurred to the participant during 0-14 days after each dose of vaccination.
Unsolicited Adverse Events28 or 30 days after each dose of vaccinationOther adverse events that occurred among participants within 0-28/30 days after each vaccination, in addition to the solicited adverse events.
Abnormal incidence rate of electrocardiogram14 days after each dose of vaccinationAbnormal electrocardiogram after 14 days of vaccination with each dose.
Serious Adverse Events (SAE)12 months after the last doseThat is serious adverse events, any serious adverse events that occurred to the participant during the study period.
Adverse Event of Special Interest (AESI)12 months after the last doseAdverse events that require special attention as specified in the experimental protocol.

Other

MeasureTime frameDescription
Geometric Mean Titer (GMT) of neutralizing antibodies14 days after the first dose of vaccine, before the second dose of vaccine and14 days, 28 days, 6 months, and 12 months after the second doseGMI of neutralizing antibodies against monkeypox virus in the experimental vaccine groups and the placebo group.
Cellular immune level14 days after the first dose of vaccine, before the second dose of vaccine and14 days, 28 days after the second doseCellular immune levels of participants after receiving the experimental vaccine or placebo.
Seroconversion rate of neutralizing antibodies14 days after the first dose of vaccine, before the second dose of vaccine and14 days, 28 days, 6 months, and 12 months after the second doseThe neutralizing antibody seroconversion rate against monkeypox virus in the experimental vaccine groups and the placebo group.
Seropositive rate of neutralizing antibodies14 days after the first dose of vaccine, before the second dose of vaccine and14 days, 28 days, 6 months, and 12 months after the second doseThe neutralizing antibody seropositive rate against monkeypox virus in the experimental vaccine groups and the placebo group.
GMT of binding antibody14 days after the first dose of vaccine, before the second dose of vaccine and14 days, 28 days, 6 months, and 12 months after the second doseGMI of binding antibody against monkeypox virus in the experimental vaccine groups and the placebo group.
Seroconversion rate of binding antibody14 days after the first dose of vaccine, before the second dose of vaccine and14 days, 28 days, 6 months, and 12 months after the second doseThe binding antibody seroconversion rate against monkeypox virus in the experimental vaccine groups and the placebo group.
Seropositive rate of binding antibody14 days after the first dose of vaccine, before the second dose of vaccine and14 days, 28 days, 6 months, and 12 months after the second doseThe binding antibody seropositive rate against monkeypox virus in the experimental vaccine groups and the placebo group.

Countries

China

Contacts

Primary ContactHao Zhou, Bachelor
zhouhao5@sinopharm.com86-021-62800991
Backup ContactLi

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026