A study to evaluate the immunogenicity and safety of smallpox vaccine as vaccination to monkeypox in healthy adults

A single-arm study to evaluate the immunogenicity and safety of smallpox vaccine as vaccination to monkeypox in Japanese healthy adults

Status

Active, not recruiting

Phases

Phase 1

Study type

Interventional

Source

JPRN

Registry ID

JPRN-jRCTs031220171

Enrollment

Registered

2022-06-30

Start date

2022-07-04

Completion date

Unknown

Last updated

2025-07-18

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

Conditions

Monkeypox Monkeypox

Interventions

Smallpox vaccine will be administerd to healthy adults

D012899

Smallpox vaccine

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1) Persons who have given written consent to participate in the research in person. 2) Men and women who are at least 20 year of age at the time consent is obtained 3) Persons who are expected to work for patients with monkeypox in National Center of Global Health and Medicine 4) Persons who have developed neither monkeypox nor smallpox.

Exclusion criteria

Exclusion criteria: 1) Persons with diseases that are clearly abnormalin immune function 2) Persons using corticosteroids or immunosuppressive drugs (cyclosporine, tacrolimus, azathioprine, biological drugs) 3) Persons with an apparent history of anaphylaxiscaused by components of the smallpox vaccine 4) Patients with apparent fever 5) Persons who are obviously suffering from a serious acute disease 6) Those who are obviously pregnant 7) Persons suffering from a spreading skin disease,which may be impaired by immunization. 8) Persons who are in an inappropriate condition to be immunized. 9) Persons who are judged by the principal investigator to be inappropriate for inclusion in the study.

Design outcomes

Primary

Measure	Time frame
The proportion of participants with neutralizing antibody seroconversion against monkeypox virus 28 days after smallpox vaccination	—

Secondary

Measure	Time frame
1) The proportion of participants with neutralizing antibody seroconversion against monkeypox virus 14 and 168 days after smallpox vaccination 2) The proportion of participants with neutralizing antibody seroconversion against smallpox vaccinia virus 14, 28 and 168 days after smallpox vaccination 3) The proportion of participants developed major skin reactions after 14 days vacccination 4) The proportion of participants developed monkeypox within 168 days after smallpox vaccination 5) Safety	—

Measure

Time frame

1) The proportion of participants with neutralizing antibody seroconversion against monkeypox virus 14 and 168 days after smallpox vaccination 2) The proportion of participants with neutralizing antibody seroconversion against smallpox vaccinia virus 14, 28 and 168 days after smallpox vaccination 3) The proportion of participants developed major skin reactions after 14 days vacccination 4) The proportion of participants developed monkeypox within 168 days after smallpox vaccination 5) Safety

—

Contacts

Public ContactMorino Eriko

Center for Clinical Sciences of the National Center for GlobalHealth and Medicine

before_e_mkp3@hosp.ncgm.go.jp+81-3-3202-7181

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Feb 6, 2026