A new study is set to begin in the Democratic Republic of Congo (DRC) to assess the efficacy of the LC16m8 Mpox vaccine in African populations.
The launch comes as the country battles a major outbreak of the virus, which remains a continental public health emergency.
Health experts say the ongoing vaccination campaign in DRC offers a rare chance to gather real-world evidence about the vaccine’s performance. The study will look at how effective the vaccine is at preventing Mpox, including among children.
The Coalition for Epidemic Preparedness Innovations (CEPI) is funding the project with up to 10.4 million US dollars, a statement issued on September 11, 2025, said. The International Vaccine Institute (IVI) will serve as the study sponsor, while the Institut National pour la Recherche Biomédicale (INRB) in the DRC will co-sponsor and also lead the research and the Japan Institute for Health Security (JIHS) will act as a co-investigator.
The study is supported by the DRC Ministry of Health and the Institut National de Santé Publique (INSP) and is expected to begin this Autumn once regulatory and ethics approvals are completed.
Researchers will monitor vaccinated people in hotspot health zones in Équateur Province. They will track how many still get infected and also collect safety data from a subset of participants.
The findings are expected to guide vaccination strategies in the DRC and other Mpox-endemic regions. They could also help decide which age groups should be prioritized for vaccination.
Japan has donated three million doses of LC16m8 to DRC to protect at-risk populations. The vaccine, developed by KM Biologics, has been licensed in Japan for decades as a smallpox vaccine. It is safe and effective, including in people with well-controlled HIV.
The DRC Health Minister, Samuel Roger Kamba, said the country will be the first in Africa to collect real-world field data on the vaccine.
“The epidemiological data on Mpox have enabled us to support the response with vaccination of the populations. With this collaborative research, the DRC will be the first African country to collect essential field data on the use of the LC16m8 vaccine against Mpox.”
Dr. Manabu Sumi of Japan’s Health Ministry said LC16m8 is the only Mpox vaccine currently approved for children and could protect people of all ages.
“Building on the findings of this trial and Japan’s accumulated experience, the Ministry looks forward to working with international partners to further enhance LC16m8’s contribution to global preparedness and response efforts against Mpox.”
Africa CDC Director-General, Dr. Jean Kaseya, described the study as “a vital step in protecting Africa’s most vulnerable, especially children.”
“By turning science into action, we are building the evidence needed to guide vaccination and strengthen health security across the continent.”
Other partners, including INRB and JIHS, stressed that the project will also strengthen Africa’s ability to respond to future health emergencies.
Director-General of INRB and Principal Investigator, Prof. Jean-Jacques Muyembe, said scientific collaboration is key.
“The results generated by this study will serve as an effective guide for future Mpox outbreaks,” he said.
Dr. Norio Ohmagari of JIHS said the trial will provide rigorous real-world evidence, while Dr. Mugen Ujiie of the same institute highlighted Japan’s commitment to protecting communities from Mpox.
“The findings will help inform equitable and effective vaccination strategies across affected regions,” Dr Ujiie said.
The International Vaccine Institute’s Deputy Director General, Dr. Florian Marks, added that the study will also help build local research capacity.
“In close partnership with INRB, JIHS, CEPI, and local health teams, we are also working to strengthen local research capacity so that communities are better equipped to respond to future health emergencies,” he said.
General Director of INSP, Dr. Dieudonné Mwamba, said vaccination remains a key pillar in responding to epidemics.
Mpox, formerly known as monkeypox, causes fever, headache, muscle aches, swollen lymph nodes and skin rashes with blisters. The disease can be deadly in severe cases.
WHO and Africa CDC declared the ongoing outbreak a global and continental emergency in August 2024. As of September 2025, Mpox remains a continental health emergency in Africa.