An Open-Label Prospective Cohort Study of JYNNEOS Smallpox Vaccine in Adult Healthcare Personnel at Risk for Mpox in the Democratic Republic of the Congo

CDC-IRB-6859

Mpox is a febrile rash illness caused by the monkeypox virus. Its natural occurrence in the DRC puts healthcare and frontline workers at high risk of acquiring monkeypox virus infections that can prevent them from performing work duties, compromise the overall healthcare delivery in an already fragile system, and can result in death (case fatality estimates are approximately 10%). This is an open-label prospective cohort study in up to 1,600 eligible healthcare workers at risk of mpox infection through their daily work. The study will document mpox exposure and infection in participants while concurrently evaluating the immunogenicity and safety of the vaccine, JYNNEOS (also known as MVA-BN, IMVAMUNE®, IMVANEX), in healthcare personnel in the DRC. Participation in the study is voluntary and open to male and female healthcare personnel ages 18 years and older in Tshuapa Province in The Democratic Republic of Congo who are at risk of monkeypox virus infection through their daily work or laboratory personnel performing diagnostic testing for monkeypox virus.

2017-02-23

2025-12-31

2025-12-31

Active (not recruiting)

Early phase I

1600

Inclusion Criteria: 1. Males and nonpregnant females (as indicated by a negative urine pregnancy test prior to first dose of vaccine) age 18 years and older. 2. Healthcare personnel at risk of mpox infection working in the Tshuapa Province of DRC or laboratory personnel performing diagnostic testing for mpox at the time of enrollment 3. Willing to adhere to infection control recommendations to the extent possible based on availability of resources. 4. Able and willing to complete the informed consent process and study procedures (including blood sample collection, urine pregnancy test, and completion of adverse event diary and exposure forms). 5. Available for all study visits. Exclusion Criteria: 1. Any history of allergy or anaphylaxis to any prior vaccines, eggs, or aminoglycosides. 2. Current pregnancy (a negative urine pregnancy test is required for women participants who self-report as not pregnant). Enrollment for such participants may be deferred to a later time at which this criteria can be met. 3. Acute illness that is accompanied by an axillary temperature ≥37.2°C (99.0°F) at the time of vaccination. Enrollment for such participants may be deferred to a later time at which this criteria can be met. 4. Known experimental research agents or other vaccine within 28 days (4 weeks) prior to vaccination. Enrollment for such participants may be deferred to a later time at which this criteria can be met. 5. Any reason the PIs suspect that data collected from this person would be incomplete or of poor quality. 6. Any condition that the PIs suspect may place the participant at an unacceptable risk of injury or render the participant unable to meet the requirements of the protocol.

{'studyType': 'INTERVENTIONAL', 'phases': ['PHASE3'], 'designInfo': {'allocation': 'NON_RANDOMIZED', 'interventionModel': 'SEQUENTIAL', 'primaryPurpose': 'PREVENTION', 'maskingInfo': {'masking': 'NONE'}}, 'enrollmentInfo': {'count': 1600, 'type': 'ACTUAL'}}

2024-04-09