Two-dose MVA monkeypox live vaccine in adults

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

This trial will test whether two doses of an MVA-strain monkeypox live vaccine are safe and produce an immune response in adults, including healthy people, men who have sex with men, and people living with HIV.

Quick facts

• Phase: Phase 1
• Study type: Interventional
• Enrollment: 120 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Shanghai Institute Of Biological Products (Industry-sponsored)
• Drugs / interventions: chemotherapy, radiation
• Locations: 1 site (Zhengzhou, Henan)
• Trial ID: NCT06771479 on ClinicalTrials.gov

What this trial studies

This randomized, double-blind, placebo-controlled phase I trial will enroll 120 adults to receive two injections of either low-dose MVA, high-dose MVA, or placebo on day 0 and day 28. Participants are stratified into healthy adults, men who have sex with men, and people living with HIV in a 2:1:1 ratio and are further grouped by prior smallpox vaccination history. The primary focus is safety and reactogenicity, with immunogenicity endpoints comparing antibody and cellular responses across dose groups and placebo. Follow-up includes diary cards and scheduled visits to monitor adverse events and immune markers.

Who should consider this trial

Good fit: Adults aged 18 or older who can provide informed consent, attend all follow-up visits, and meet the study group criteria (healthy, men who have sex with men, or people living with HIV) are ideal candidates.

Not a fit: People with recent monkeypox infection, known allergies to vaccine components, or recent close contact with monkeypox are unlikely to benefit or may be excluded.

Why it matters

Potential benefit: If successful, the vaccine could provide a safe option to prevent monkeypox by generating protective immune responses in adults, including those living with HIV.

How similar studies have performed: MVA-based vaccines have shown immunogenicity and good safety profiles in other orthopoxvirus studies, though this specific live-attenuated MVA formulation for monkeypox is still being tested.

Eligibility criteria

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 exclusion criteria for the first dose, the researcher shall determine whether to continue participating in the trial.

Where this trial is running

Zhengzhou, Henan

• Henan Infectious Disease Hospital — Zhengzhou, Henan, China (Recruiting)

Study contacts

• Principal investigator: Shuang Li, Master — Henan Infectious Disease Hospital
• Study coordinator: Hao Zhou, Bachelor

Conditions Monkeypox; Monkeypox vaccine; safety; vaccine; immunogenicity