Monkeypox Virus InfectionPhase 3NCT02977715
JYNNEOS Smallpox Vaccine in Adult Healthcare Personnel at Risk for Mpox in the Democratic Republic of the Congo
A Phase 3 study testing JYNNEOS (Liquid Formulation) and JYNNEOS (Lyophilized Formulation) in people with Monkeypox Virus Infection, run by Centers for Disease Control and Prevention at 1 site in Democratic Republic of the Congo.
Trial summary
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… Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Monkeypox Virus Infection
- What is being tested?
- JYNNEOS (Liquid Formulation) and JYNNEOS (Lyophilized Formulation)
- Type of treatment
- Vaccines, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 1,600 participants
- Where
- 1 siteDemocratic Republic of the Congo
- Study dates
- 23 Feb 2017to 31 Oct 2025
- Phase
- Phase 3
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Males and nonpregnant females (as indicated by a negative urine pregnancy test prior to first dose of vaccine) age 18 years and older.
- 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
- Willing to adhere to infection control recommendations to the extent possible based on availability of resources.
- 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).
- Available for all study visits.
Who cannot join
- Any history of allergy or anaphylaxis to any prior vaccines, eggs, or aminoglycosides.
- 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.
- 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.
- 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.
- Any reason the PIs suspect that data collected from this person would be incomplete or of poor quality.
- 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.
Trial locations and contacts
1 site in 1 country.
Democratic Republic of the Congo1 site
Tshuapa site
Boende, Tshuapa
About this study
Official title: 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
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.
Read the detailed description
Orthopoxvirus infections produce antibody responses that are cross-protective against other viruses within the genus. It is this property of orthopoxviruses that allows a vaccine for vaccinia virus against smallpox to be used to provide protection against mpox. Studies performed during and in the immediate aftermath of smallpox eradication demonstrated that smallpox vaccination (with a first generation vaccine) could confer protection against infection with monkeypox virus. Newer, third generation vaccines such as JYNNEOS, an attenuated (replication deficient) strain of vaccinia virus may offer an alternative safer source of vaccine-derived protection.
The clinical presentation of mpox infection is similar to smallpox, although it is less transmissible human-to-human than smallpox and less deadly (case fatality estimates for mpox are approximately 10%). Naturally-occurring human mpox is largely restricted to remote regions of the Congo Basin forest in Central Africa. This study is the first rigorous evaluation of JYNNEOS in a region where natural Orthopoxvirus transmission occurs at appreciable and predictable rates. Healthcare and frontline workers in the DRC are currently at high risk of acquiring monkeypox virus infection that prevents them from performing work duties, compromises healthcare delivery in an already fragile system, and can result in death.
This open-label prospective cohort study in up to 1,600 healthcare personnel at risk of mpox infection through their daily work will document monkeypox virus exposure and infection in vaccinated participants while concurrently evaluating the immunogenicity and safety of JYNNEOS vaccine. Study participation is voluntary and open to male and female healthcare personnel ages 18 years and older in Tshuapa Province in the DRC. Participants will receive two subcutaneous doses of JYNNEOS vaccine on days 0 and 28. A subset of study participants will receive a booster dose. Blood samples will be obtained on days 0, 14, 28, 42, 180, 365, 545, and 730 following primary vaccination for immunogenicity analysis. For individuals who receive a booster dose, blood samples will be obtained on Days 3, 7, 14, and > 1 year following booster vaccination. After each vaccination participants will be observed for at least thirty minutes. They will maintain an adverse event diary to record systemic and local adverse events for 7 days after each immunization. They will also record exposure to the monkeypox virus in an exposure diary that is reviewed at each follow-up visit.
The study will evaluate the proportion of participants who after being vaccinated 1) develop suspected or confirmed mpox infection, and 2) experience exposure to monkeypox virus. The study will also evaluate the safety and immunogenicity of JYNNEOS.
- Conditions
- Monkeypox Virus Infection
- Being tested
- JYNNEOS (Liquid Formulation), JYNNEOS (Lyophilized Formulation)
- Keywords
- Democratic Republic of the Congo, Modified Vaccinia Ankara (MVA), Monkeypox, Orthopoxvirus, Vaccine, Vaccinia virus, JYNNEOS, Mpox
- Medical subject headings
- Mpox, Monkeypox, Vaccinia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
JYNNEOS (Liquid Formulation)Biological
Also called Modified Vaccinia Ankara (MVA), MVA-BN, IMVAMUNE, IMVANEX
Two doses of attenuated live virus smallpox vaccine (JYNNEOS liquid formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose.
JYNNEOS (Lyophilized Formulation)Biological
Also called Modified Vaccinia Ankara (MVA), MVA-BN, IMVAMUNE, IMVANEX
Two doses of attenuated live virus smallpox vaccine (JYNNEOS lyophilized formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose.
| Study group | Role | What they receive |
|---|---|---|
| Intervention (Liquid Formulation) | Experimental | Up to 1000 male and female healthcare personnel ages 18 years and older in Tshuapa Province in The Democratic Republic of Congo at risk for mpox will receive two doses of attenuated live virus smallpox vaccine (JYNNEOS liquid formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose. Receives: Biological: JYNNEOS (Liquid Formulation) |
| Intervention (Lyophilized Formulation) | Experimental | Up to 600 male and female healthcare personnel ages 18 years and older in Tshuapa Province in The Democratic Republic of Congo at risk for mpox will receive two doses of attenuated live virus smallpox vaccine (JYNNEOS lyophilized formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose. Receives: Biological: JYNNEOS (Lyophilized Formulation) |
| Single booster dose (Liquid Formulation) | Experimental | Up to 400 male and female healthcare personnel ages 18 years and older who received primary vaccination as a previous study participant Receives: Biological: JYNNEOS (Liquid Formulation) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Monkeypox virus infection
Proportion of participants who develop suspected or confirmed monkeypox virus infection following receipt of JYNNEOS
Measured: 2 years following initial vaccination
Monkeypox virus exposure
Proportion of participants who experience exposure to monkeypox virus following receipt of JYNNEOS
Measured: 2 years following initial vaccination
Orthopoxvirus Antibody Response
Proportion of participants who have orthopoxvirus antibody responses
Measured: Days 0, 14, 28, 42, 180, 365, 545, and 730 days after the receipt of the first dose of vaccine; Days 3, 7, and/or 14, and through study completion (an average of 1 year) after receipt of single booster dose of vaccine.
Distribution of Geometric Means Titers (GMTs)
Distribution of geometric means titers (GMTs)
Measured: Days 0, 14, 28, 42, 180, 365, 545, and 730 days after the receipt of the first dose of vaccine; Days 3, 7, and/or 14, and through study completion (an average of 1 year) after receipt of single booster dose of vaccine.
Adverse event and serious adverse event information
Number of participants with reported local or systemic vaccine-associated adverse events by dose, including Serious Adverse Events and Deaths
Measured: 2 years following initial vaccination; Day 3, 7, and/or 14 after receipt of single booster dose of vaccine
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Nov 2016 (estimated)
- Study start23 Feb 2017
- Primary completion31 Oct 2025
- Study completion31 Oct 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for Monkeypox Virus InfectionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Prevention
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Enrolment
- 1,600 participants (actual)
Sponsor and investigators
- Lead sponsor
- Centers for Disease Control and Prevention
- Sponsor type
- US federal agency
- Collaborators
- Ministry of Public Health, Democratic Republic of the Congo, Kinshasa School of Public Health, Bavarian Nordic
- Responsible party
- Sponsor
- Investigators
- Faisal Minhaj, Pharm.D., MPH, DABAT, Principal investigator, Centers for Disease Control and PreventionKinkodi Didine Kaba, MD, PhD, Principal investigator, DRC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02977715
- Sponsor's protocol ID
- CDC-IRB-6859
- Status last verified
- Apr 2026
- First submitted
- 7 Sep 2016
- Last updated
- 23 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Priyamvada L, Minhaj FS, Likafi T, Pukuta E, Muyamuna E, Carson WC, Moriarty M, Rodriguez S, Joseph T, Kabamba J, Kokola G, Lushima RS, Muyembe-Tamfum JJ, Hughes CM, Petersen BW, Yu Y, Rao A, McCollum AM, Kaba DK, Nguete BU, Satheshkumar PS, Townsend MB. Immunogenicity and safety of MVA-BN vaccine administered 5 years after a two-dose primary series in DR Congo: a prospective cohort study. Lancet Infect Dis. 2026 Jun;26(6):571-580. doi: 10.1016/S1473-3099(26)00001-0. Epub 2026 Mar 9.
PubMed 41819114Minhaj FS, Mandra A, Nguete BU, Likafi T, Kokola G, Tran S, Kennedy JL, Monroe B, Hughes CM, Joseph T, Person MK, Townsend MB, Satheshkumar PS, Kabamba J, Reynolds MG, Rao AK, Kasongo D, Yu PA, Yu Y, Shongo Lushima R, Kaba D, Petersen B, McCollum AM. Safety of MVA-BN vaccine in health-care personnel in DR Congo: a prospective cohort study. Lancet Infect Dis. 2026 Jun;26(6):561-570. doi: 10.1016/S1473-3099(25)00779-0. Epub 2026 Mar 9.
PubMed 41819117Petersen BW, Kabamba J, McCollum AM, Lushima RS, Wemakoy EO, Muyembe Tamfum JJ, Nguete B, Hughes CM, Monroe BP, Reynolds MG. Vaccinating against monkeypox in the Democratic Republic of the Congo. Antiviral Res. 2019 Feb;162:171-177. doi: 10.1016/j.antiviral.2018.11.004. Epub 2018 Nov 14.
PubMed 30445121Hatmal MM, Al-Hatamleh MAI, Olaimat AN, Ahmad S, Hasan H, Ahmad Suhaimi NA, Albakri KA, Abedalbaset Alzyoud A, Kadir R, Mohamud R. Comprehensive literature review of monkeypox. Emerg Microbes Infect. 2022 Dec;11(1):2600-2631. doi: 10.1080/22221751.2022.2132882.
PubMed 36263798
Study at a glance
From the registry record, last updated by the sponsor on 23 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- 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
- ClinicalTrials.gov ID
- NCT02977715
- Acronym / sponsor ID
- CDC-IRB-6859
- Conditions
- Monkeypox Virus Infection
- Keywords
- Democratic Republic of the Congo, Modified Vaccinia Ankara (MVA), Monkeypox, Orthopoxvirus, Vaccine, Vaccinia virus, JYNNEOS, Mpox
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 1,600 participants (actual)
- Lead sponsor
- Centers for Disease Control and PreventionUS federal agency
- Collaborators
- Ministry of Public Health, Democratic Republic of the Congo, Kinshasa School of Public Health, Bavarian Nordic
- Study start
- 23 Feb 2017 (actual)
- Primary completion
- 31 Oct 2025 (actual)
- Study completion
- 31 Oct 2025 (actual)
- First posted
- 30 Nov 2016 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
Orthopoxvirus infections produce antibody responses that are cross-protective against other viruses within the genus. It is this property of orthopoxviruses that allows a vaccine for vaccinia virus against smallpox to be used to provide protection against mpox. Studies performed during and in the immediate aftermath of smallpox eradication demonstrated that smallpox vaccination (with a first generation vaccine) could confer protection against infection with monkeypox virus. Newer, third generation vaccines such as JYNNEOS, an attenuated (replication deficient) strain of vaccinia virus may offer an alternative safer source of vaccine-derived protection.
The clinical presentation of mpox infection is similar to smallpox, although it is less transmissible human-to-human than smallpox and less deadly (case fatality estimates for mpox are approximately 10%). Naturally-occurring human mpox is largely restricted to remote regions of the Congo Basin forest in Central Africa. This study is the first rigorous evaluation of JYNNEOS in a region where natural Orthopoxvirus transmission occurs at appreciable and predictable rates. Healthcare and frontline workers in the DRC are currently at high risk of acquiring monkeypox virus infection that prevents them from performing work duties, compromises healthcare delivery in an already fragile system, and can result in death.
This open-label prospective cohort study in up to 1,600 healthcare personnel at risk of mpox infection through their daily work will document monkeypox virus exposure and infection in vaccinated participants while concurrently evaluating the immunogenicity and safety of JYNNEOS vaccine. Study participation is voluntary and open to male and female healthcare personnel ages 18 years and older in Tshuapa Province in the DRC. Participants will receive two subcutaneous doses of JYNNEOS vaccine on days 0 and 28. A subset of study participants will receive a booster dose. Blood samples will be obtained on days 0, 14, 28, 42, 180, 365, 545, and 730 following primary vaccination for immunogenicity analysis. For individuals who receive a booster dose, blood samples will be obtained on Days 3, 7, 14, and > 1 year following booster vaccination. After each vaccination participants will be observed for at least thirty minutes. They will maintain an adverse event diary to record systemic and local adverse events for 7 days after each immunization. They will also record exposure to the monkeypox virus in an exposure diary that is reviewed at each follow-up visit.
The study will evaluate the proportion of participants who after being vaccinated 1) develop suspected or confirmed mpox infection, and 2) experience exposure to monkeypox virus. The study will also evaluate the safety and immunogenicity of JYNNEOS.
Study design
- Primary purpose
- Prevention
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Intervention (Liquid Formulation) | Experimental | Biological: JYNNEOS (Liquid Formulation)Up to 1000 male and female healthcare personnel ages 18 years and older in Tshuapa Province in The Democratic Republic of Congo at risk for mpox will receive two doses of attenuated live virus smallpox vaccine (JYNNEOS liquid formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose. |
| Intervention (Lyophilized Formulation) | Experimental | Biological: JYNNEOS (Lyophilized Formulation)Up to 600 male and female healthcare personnel ages 18 years and older in Tshuapa Province in The Democratic Republic of Congo at risk for mpox will receive two doses of attenuated live virus smallpox vaccine (JYNNEOS lyophilized formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose. |
| Single booster dose (Liquid Formulation) | Experimental | Biological: JYNNEOS (Liquid Formulation)Up to 400 male and female healthcare personnel ages 18 years and older who received primary vaccination as a previous study participant |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Males and nonpregnant females (as indicated by a negative urine pregnancy test prior to first dose of vaccine) age 18 years and older.
- 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
- Willing to adhere to infection control recommendations to the extent possible based on availability of resources.
- 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).
- Available for all study visits.
Key exclusion criteria (6 listed)
- Any history of allergy or anaphylaxis to any prior vaccines, eggs, or aminoglycosides.
- 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.
- 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.
- 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.
- Any reason the PIs suspect that data collected from this person would be incomplete or of poor quality.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| JYNNEOS (Liquid Formulation)Also: Modified Vaccinia Ankara (MVA), MVA-BN, IMVAMUNE, IMVANEXTwo doses of attenuated live virus smallpox vaccine (JYNNEOS liquid formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose. | Biological | Intervention (Liquid Formulation), Single booster dose (Liquid Formulation) |
| JYNNEOS (Lyophilized Formulation)Also: Modified Vaccinia Ankara (MVA), MVA-BN, IMVAMUNE, IMVANEXTwo doses of attenuated live virus smallpox vaccine (JYNNEOS lyophilized formulation) administered on days 0 and 28 via subcutaneous injection (deltoid) (1 x 10^8 Tissue Culture Infectious Dose 50 [TCID50] per 0.5 mL). A subset of participants will receive a booster dose. | Biological | Intervention (Lyophilized Formulation) |
Primary outcome
Monkeypox virus infection
Time frame: 2 years following initial vaccination
Proportion of participants who develop suspected or confirmed monkeypox virus infection following receipt of JYNNEOS
Monkeypox virus exposure
Time frame: 2 years following initial vaccination
Proportion of participants who experience exposure to monkeypox virus following receipt of JYNNEOS
Orthopoxvirus Antibody Response
Time frame: Days 0, 14, 28, 42, 180, 365, 545, and 730 days after the receipt of the first dose of vaccine; Days 3, 7, and/or 14, and through study completion (an average of 1 year) after receipt of single booster dose of vaccine.
Proportion of participants who have orthopoxvirus antibody responses
Distribution of Geometric Means Titers (GMTs)
Time frame: Days 0, 14, 28, 42, 180, 365, 545, and 730 days after the receipt of the first dose of vaccine; Days 3, 7, and/or 14, and through study completion (an average of 1 year) after receipt of single booster dose of vaccine.
Distribution of geometric means titers (GMTs)
Adverse event and serious adverse event information
Time frame: 2 years following initial vaccination; Day 3, 7, and/or 14 after receipt of single booster dose of vaccine
Number of participants with reported local or systemic vaccine-associated adverse events by dose, including Serious Adverse Events and Deaths
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Apr 2026.
- Results publication: PubMed 41819114Priyamvada L, Minhaj FS, Likafi T, Pukuta E, Muyamuna E, Carson WC, Moriarty M, Rodriguez S, Joseph T, Kabamba J, Kokola G, Lushima RS, Muyembe-Tamfum JJ, Hughes CM, Petersen BW, Yu Y, Rao A, McCollum AM, Kaba DK, Nguete BU, Satheshkumar PS, Townsend MB. Immunogenicity and safety of MVA-BN vaccine administered 5 years after a two-dose primary series in DR Congo: a prospective cohort study. Lancet Infect Dis. 2026 Jun;26(6):571-580. doi: 10.1016/S1473-3099(26)00001-0. Epub 2026 Mar 9.
- Results publication: PubMed 41819117Minhaj FS, Mandra A, Nguete BU, Likafi T, Kokola G, Tran S, Kennedy JL, Monroe B, Hughes CM, Joseph T, Person MK, Townsend MB, Satheshkumar PS, Kabamba J, Reynolds MG, Rao AK, Kasongo D, Yu PA, Yu Y, Shongo Lushima R, Kaba D, Petersen B, McCollum AM. Safety of MVA-BN vaccine in health-care personnel in DR Congo: a prospective cohort study. Lancet Infect Dis. 2026 Jun;26(6):561-570. doi: 10.1016/S1473-3099(25)00779-0. Epub 2026 Mar 9.
- Results publication: PubMed 30445121Petersen BW, Kabamba J, McCollum AM, Lushima RS, Wemakoy EO, Muyembe Tamfum JJ, Nguete B, Hughes CM, Monroe BP, Reynolds MG. Vaccinating against monkeypox in the Democratic Republic of the Congo. Antiviral Res. 2019 Feb;162:171-177. doi: 10.1016/j.antiviral.2018.11.004. Epub 2018 Nov 14.
- Derived from this study: PubMed 36263798Hatmal MM, Al-Hatamleh MAI, Olaimat AN, Ahmad S, Hasan H, Ahmad Suhaimi NA, Albakri KA, Abedalbaset Alzyoud A, Kadir R, Mohamud R. Comprehensive literature review of monkeypox. Emerg Microbes Infect. 2022 Dec;11(1):2600-2631. doi: 10.1080/22221751.2022.2132882.
- Individual participant dataSharing planned: No
Related trials for Monkeypox Virus Infection
Active, not recruitingPhase 1
A Clinical Trial Evaluating the Monkeypox Recombinant Protein Vaccine
Health Volunteer
RecruitingObservational study
Evaluation of Effectiveness and Safety of LC16m8 Mpox Vaccine in the Democratic Republic of Congo (DRC)
Mpox (Monkeypox), Mpox
Enrolling by invitationObservational study
New York City Observational Study of Mpox Immunity
Monkeypox, Mpox
Enrolling by invitation
Smart Analysis and Decision-Making for Emerging Infectious Diseases
Emerging Infectious Diseases, COVID-19
Active, not recruitingPhase 4
Smallpox Vaccine for Mpox Post-Exposure Prophylaxis: A Cluster RCT
Monkeypox
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Faisal Minhaj, Pharm.D., MPH, DABAT principal investigator
Centers for Disease Control and Prevention
Kinkodi Didine Kaba, MD, PhD principal investigator
DRC
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing JYNNEOS (Liquid Formulation) and JYNNEOS (Lyophilized Formulation) in people with Monkeypox Virus Infection, run by Centers for Disease Control and Prevention at 1 site in Democratic Republic of the Congo.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 23 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Democratic Republic of the Congo. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Monkeypox virus infection (time frame: 2 years following initial vaccination). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02977715, which also lists 4 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Apr 2026.