MVA-BN vaccine to prevent mpox in adults living with HIV in Kinshasa

The Mpox Biology, Outcome, Transmission and Epidemiology Project - HIV Immunization and Vaccination Against Mpox eXposure Trial

Phase 2 Interventional Institute of Tropical Medicine, Belgium · NCT06839989

This trial will test whether two standard doses of the MVA-BN vaccine given 28 days apart are safe and produce strong immune responses in adults living with HIV in Kinshasa.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment600 (estimated)
Ages18 Years to 45 Years
SexAll
SponsorInstitute of Tropical Medicine, Belgium Academic / other
Locations1 site (Kinshasa)
Trial IDNCT06839989 on ClinicalTrials.gov

What this trial studies

This is an open-label phase 2 trial enrolling 600 adults living with HIV in Kinshasa who are on antiretroviral therapy. Participants are stratified into three groups by CD4 count (<200, 200–499, ≥500 cells/µL) with 200 people per group and will receive two subcutaneous MVA-BN doses 28 days apart. Safety and immune responses will be measured across six visits over about seven months. The study excludes people with prior smallpox/mpox vaccination, recent mpox exposure, pregnancy, or severe uncontrolled infections.

Who should consider this trial

Good fit: Adults aged 18–45 living with HIV who have been on combination ART for at least 8 weeks, without prior smallpox/mpox vaccination or recent mpox exposure, and willing to follow the visit schedule and contraception requirements if applicable.

Not a fit: People who are pregnant, have a history of smallpox/mpox vaccination or recent close contact with a confirmed mpox case, or who have uncontrolled severe infections are unlikely to benefit or will be excluded.

Why it matters

Potential benefit: If successful, the vaccine could offer a safe and effective way to prevent mpox in adults living with HIV across a range of immune statuses.

How similar studies have performed: MVA-BN (Jynneos/Imvamune/Imvanex) has been used widely and shown immunogenicity and an acceptable safety profile, though data specifically across low CD4 subgroups remain limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age ≥ 18 years and ≤ 45 years at time of informed consent
* Able and willing to provide written informed consent
* Infected with HIV and receiving combination antiretroviral therapy (ART) for ≥ 8 weeks prior to study entry and vaccination
* Preparedness to follow the study schedule
* Willingness to use contraception for 1 month after each vaccination (only for women of childbearing potential)

Exclusion Criteria:

* A known history of mpox and/or smallpox
* A known history of vaccination with 1st, 2nd or 3rd generation smallpox vaccines, or vaccine platforms that contain MVA as a vector
* Planned MVA-based vaccination (other than study vaccination) during the trial
* Close contact to a confirmed mpox case in the 3 weeks prior to study enrollment
* Uncontrolled severe infection or other condition requiring hospitalization
* Pregnancy
* History of anaphylaxis or severe allergic reaction to any vaccine or known allergy to one of the components of the study vaccine

Where this trial is running

Kinshasa

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions MpoxMVA-BNVaccination
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.