A Phase 4 interventional study of MVA-BN vaccine in Monkeypox, sponsored by National Institute of Allergy and Infectious Diseases (NIAID). Completed at 3 sites in Democratic Republic of the Congo. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-02-12.
Sponsored by National Institute of Allergy and Infectious Diseases (NIAID) · Phase 4, Interventional, and Prevention
The goal of this observational study is to monitor and assess the safety profile of the MVA-BN vaccine among staff and study personnel of the PALM-007 study in the Democratic Republic of the Congo. The main questions it aims to answer are:
Participants will receive two doses of vaccine and will be actively followed up to the 28th day after their last dose of MVA-BN vaccine.
All personnel and staff of the PALM-007 study will be offered the opportunity to participate in the study by reviewing and signing the informed consent. After signing informed consent, participants will be examined. The following parameters will be assessed:
If a participant has met all eligibility criteria, they will be enrolled and will receive the vaccine as specified below. Participants who are excluded because of fever can be rescreened and included after resolution of the fever and its cause.
Enrolled participants will receive the MVA-BN vaccine by subcutaneous injection of 0.5 mL in the shoulder (left or right).
The first dose will be administered at the time of enrollment and the second dose 28 days later.
After each vaccination, the participant will remain under observation for 30 minutes. All AEs occurring during this period of observation will be recorded and reported to the National Center for Pharmacovigilance and to the ethics committee according to Congolese regulations.
Follow-up of participants:
Participants will be followed until 28 days after the second dose of vaccine. Follow-up visit will be done either in person at National Institute of Biomedical Research (INRB) in Kinshasa and at the Monkeypox treatment centers in the PALM-007 study or by phone calls on Day 3, Day 14, and Day 28 post each vaccination. Study participants will be provided with contact information of vaccine research staff and have the right to contact the research team either directly or by phone if they have any questions about post-vaccination reactions they may be experiencing or if they are concerned. There is a window of +/- one day for each study visit except the day of the second dose which can be done on day 28 after the first dose with a window of +7 days. This second dose must not be given before Day 28. During each visit, participants will be asked to report to the research team AEs via open-ended questions. All SAEs will be followed-up. SAEs that have not resolved by the end of the per-protocol follow-up period for the subject (Day 28 after second dose) are to be followed until final outcome is known (to the degree permitted by the IRB-approved informed consent form). If it is not possible to obtain a final outcome for an SAE (e.g., the participant is lost to follow-up), the last known status and the reason a final outcome could not be obtained will be recorded by the investigator on an SAE report update and the CRF.
On the day of administration of the second dose of vaccine, vital signs, and physical examination will be done to all participants and a pregnancy test will be done on all women of childbearing potential prior to vaccine administration. If the pregnancy test is positive, the second dose will not be given, and the participant will be followed up as described in the protocol. Participants will be instructed to report any AEs that are experienced outside of the protocol defined follow up days. The reporting form of the national pharmacovigilance system of the DRC will be used for reporting. The research team will complete the notification form which will be sent to the National Pharmacovigilance Center (CNPV) by e-mail (scanned copies).
72 studies on the registry are indexed under Mpox, Monkeypox; 30 are open to participants now.
This study's enrollment of 500 is above the median of 305 across 36 interventional studies indexed under Mpox, Monkeypox.
Browse Mpox, Monkeypox studies →National Institute of Allergy and Infectious Diseases (NIAID) is the lead sponsor of 2,446 studies on the registry; 179 are open to participants now.
Of its 405 completed or terminated interventional studies of FDA-regulated products, 302 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
2 doses of 0.5 mL MVA-BN vaccine injected subcutaneously and given at least 28 days apart
Biological: MVA-BN vaccine
A live vaccine produced from the Modified Vaccinia Ankara-Bavarian Nordic strain (MVA-BN), an attenuated and non-replicating orthopox virus
Also known as: JYNNEOS
Frequency of SAEs After First Dose of MVA-BN Vaccine
Number of participants with an SAE up to 14 days after dose
Time frame: Within 14 days of first vaccine dose
Frequency of SAEs After Second Dose of MVA-BN Vaccine
Number of participants with an SAE up to 14 days after dose
Time frame: Within 14 days of second vaccine dose
Frequency of AEs After First Dose of MVA-BN Vaccine
Number of participants with an AE within 14 days of first vaccine dose
Time frame: Within 14 days of first vaccine dose
Frequency of AEs After Second MVA-BN Vaccine Dose
Number of participants with an AE up to 28 days after second vaccine dose
Time frame: Within 28 days of second vaccine dose
Participants were recruited at three sites from March 2023 to June 2024. The first two sites were Tunda and Kole General Hospitals, in Maniema and Sankuru provinces, DRC (the two sites where participants with mpox were enrolled in the PALM 007 therapeutic RCT). The third site subsequently opened at the INRB main campus in Kinshasa, DRC. Adult participants (≥18 years) were recruited from PALM 007 study staff, although it was not mandatory for staff to be vaccinated or participate in the trial.
| Milestone | MVA-BN Mpox Vaccine |
|---|---|
| Started | 500 |
| Received first vaccine dose | 500 |
| Received second vaccine dose | 494 |
| Completed | 494 |
| Not completed | 6 |
| Withdrew: Pregnancy | 4 |
| Withdrew: Withdrawal by subject | 2 |
Number of participants with an SAE up to 14 days after dose
| Participants | MVA-BN Mpox Vaccine |
|---|---|
| Frequency of SAEs After First Dose of MVA-BN Vaccine | 0 |
Number of participants with an SAE up to 14 days after dose
| Participants | MVA-BN Mpox Vaccine |
|---|---|
| Frequency of SAEs After Second Dose of MVA-BN Vaccine | 0 |
Number of participants with an AE within 14 days of first vaccine dose
| Participants | MVA-BN Mpox Vaccine |
|---|---|
| Frequency of AEs After First Dose of MVA-BN Vaccine | 219 |
Number of participants with an AE up to 28 days after second vaccine dose
| Participants | MVA-BN Mpox Vaccine |
|---|---|
| Frequency of AEs After Second MVA-BN Vaccine Dose | 102 |
Collected over From enrollment until the end of follow-up, up to 28 days after receipt of the second vaccine dose. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| MVA-BN Mpox Vaccine | 0/500 (0%) | 0/500 (0%) | 281/500 (56.2%) |
| Event | MVA-BN Mpox Vaccine |
|---|---|
| Vaccination site painGeneral disorders and administration site conditions | 164/500 |
| HeadacheNervous system disorders | 72/500 |
| PyrexiaGeneral disorders and administration site conditions | 67/500 |
| Age, Continuous(Years) | MVA-BN Mpox Vaccine |
|---|---|
| Mean | 34.3 ± 11.4 |
| Sex: Female, Male(Participants) | MVA-BN Mpox Vaccine |
|---|---|
| Female | 109 |
| Male | 391 |
| Race and Ethnicity Not Collected(Participants) | MVA-BN Mpox Vaccine |
|---|
PDFs hosted by the registry, ClinicalTrials.gov.
Ran from Mar 2023 to primary completion in Jun 2024, 15 months.
Results were first posted in Feb 2026, 1 year 7 months after primary completion.
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Studies of the drug tested here: MVA-BN smallpox vaccine
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