A Phase 4 interventional study of Bavarian Nordic smallpox vaccine and Typhoid VI Polysaccharide Vaccine Injectable Solution in Monkeypox, sponsored by McMaster University. Active, not recruiting at 10 sites in 3 countries. Open to participants aged 2 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-12.
Sponsored by McMaster University · Phase 4, Interventional, and Prevention
A cluster randomized controlled trial to determine if smallpox vaccine reduces secondary cases and symptom severity in persons exposed to mpox.
A pragmatic, adaptive, multi-site, cluster randomized trial where households with one or more persons confirmed to have mpox will be randomized to smallpox vaccine or control. The co-primary outcomes are RT-PCR confirmed mpox and symptom severity.
72 studies on the registry are indexed under Mpox, Monkeypox; 30 are open to participants now.
This study's planned enrollment of 3,000 is above the median of 305 across 36 interventional studies indexed under Mpox, Monkeypox.
Browse Mpox, Monkeypox studies →McMaster University is the lead sponsor of 741 studies on the registry; 127 are open to participants now.
Of its 7 completed or terminated interventional studies of FDA-regulated products, 3 (43%) have results posted.
Counted across the registry records on this site, refreshed daily.
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.
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.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive the Bavarian Nordic smallpox vaccine 0.5 ml single-dose
Drug: Bavarian Nordic smallpox vaccine
Participants will receive the Typhim Vi® typhoid vaccine 0.5 ml single-dose
Drug: Typhoid VI Polysaccharide Vaccine Injectable Solution
A single dose of the Bavarian Nordic smallpox vaccine will be given at baseline.
Also known as: Imvamune
A single dose of the typhoid vaccine will be given at baseline.
PCR-confirmed Mpox
To evaluate if smallpox vaccine vs control prevents RT-PCR confirmed mpox
Time frame: 8 weeks
Symptom severity
To evaluate if smallpox vaccine vs control affects symptom severity
Time frame: 8 weeks
Resolution of skin lesions
To assess the time to resolution (i.e. a new skin layer has formed) of any skin lesion
Time frame: 8 weeks
Number of skin lesions
To assess the number of skin lesions for any participants who develop mpox
Time frame: 8 weeks
Self-reported Quality of Life
To assess the QOL of participants using the World Health Organization Quality of Life Scale
Time frame: 8 weeks
Mpox complications
To assess longitudinal complications for any participants who develop mpox
Time frame: 8 weeks
Mpox Pain
To assess pain using an adapted Zoster Brief Pain Inventory
Time frame: 8 weeks
Hospitalization
To determine all cause hospitalization over the study period
Time frame: 8 weeks
Mortality
To determine all cause mortality over the study period
Time frame: 8 weeks
Safety (SAEs, AESI)
Solicited SAE and AESIs will be followed at 4 months and 6 months
Time frame: 6 months
Plan to share: No
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: MVA-BN smallpox vaccine