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Recruiting Phase 4 NCT05745987

NCT05745987 Smallpox Vaccine for Mpox Post-Exposure Prophylaxis: A Cluster RCT

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Clinical Trial Summary
NCT ID NCT05745987
Status Recruiting
Phase Phase 4
Sponsor McMaster University
Condition Monkeypox
Study Type INTERVENTIONAL
Enrollment 3,000 participants
Start Date 2024-09-17
Primary Completion 2026-06-01

Eligibility & Interventions

Sex All sexes
Min Age 2 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
Bavarian Nordic smallpox vaccineTyphoid VI Polysaccharide Vaccine Injectable Solution

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 4 studies follow an already-approved treatment in real-world conditions to monitor long-term safety and effectiveness.

This trial targets 3,000 participants in total. It began in 2024-09-17 with a primary completion date of 2026-06-01.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

A cluster randomized controlled trial to determine if smallpox vaccine reduces secondary cases and symptom severity in persons exposed to mpox.

Eligibility Criteria

Inclusion Criteria: 1. Household member of person with laboratory confirmed mpox 2. Age ≥ 2 years 3. Within 14 days of onset of illness in mpox index case Exclusion Criteria: 1. Pregnancy 2. Breastfeeding 3. Past serious allergic reaction to study vaccine components 4. Previous smallpox vaccination 5. Current or planned use of another investigational drug at any point during study participation

Contact & Investigator

Central Contact

Mark Loeb, MD

✉ loebm@mcmaster.ca

📞 9055259140

Principal Investigator

Mark Loeb, MD

PRINCIPAL INVESTIGATOR

McMaster University

Frequently Asked Questions

Who can join the NCT05745987 clinical trial?

This trial is open to participants of all sexes, aged 2 Years or older, studying Monkeypox. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT05745987 trial and what does that mean for participants?

Phase 4 studies are conducted after a treatment has been approved. They monitor long-term safety and real-world effectiveness in a broader patient population.

Is NCT05745987 currently recruiting?

Yes, NCT05745987 is actively recruiting participants. Contact the research team at loebm@mcmaster.ca for enrollment information.

Where is the NCT05745987 trial being conducted?

This trial is being conducted at Kinshasa, Democratic Republic of the Congo, Abuja, Nigeria, Abuja, Nigeria, Ibadan, Nigeria and 6 additional locations.

Who is sponsoring the NCT05745987 clinical trial?

NCT05745987 is sponsored by McMaster University. The principal investigator is Mark Loeb, MD at McMaster University. The trial plans to enroll 3,000 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: April 2026  ·  Data Methodology