The World Health Organization (WHO) has added the LC16m8 mpox vaccine to its Emergency Use Listing (EUL), marking it as the second mpox vaccine approved by the global health body since the declaration of a public health emergency of international concern (PHEIC) on August 14, 2024.
This approval aims to enhance vaccine availability in regions experiencing surging mpox outbreaks. As of October 31, 2024, cases have been reported in 80 countries, including 19 in Africa. The Democratic Republic of the Congo (DRC) remains the hardest hit, with over 39,000 suspected cases and more than 1,000 deaths.
In a significant move, the Japanese government has pledged to donate 3.05 million doses of the LC16m8 vaccine, along with specialized inoculation needles, to the DRC. This donation represents the largest single contribution to the ongoing mpox emergency response.
About the Vaccine
Developed by KM Biologics in Japan, the LC16m8 vaccine was reviewed by WHO’s Technical Advisory Group (TAG) for EUL, which assessed its safety and programmatic suitability. The vaccine is recommended for individuals over one year of age as a single-dose administration, delivered using a bifurcated needle with a multiple puncture technique.
“WHO’s emergency use listing of the LC16m8 vaccine is a pivotal step in addressing the current mpox outbreak,” said Dr. Yukiko Nakatani, WHO Assistant Director-General for Access to Medicines and Health Products. “Vaccines play a crucial role in a comprehensive response strategy, which also includes improved diagnostics, treatment, infection prevention, and community engagement.”
Regulatory Background and Safety Considerations
The EUL approval is based on data submitted by KM Biologics and reviewed by Japan’s Pharmaceuticals and Medical Devices Agency (PMDA). The LC16m8 vaccine has a history of safe and effective use in Japan during previous mpox outbreaks, including in individuals with well-controlled HIV.
WHO’s Strategic Advisory Group of Experts (SAGE) on Immunization has recommended the vaccine’s use in outbreak settings for children and individuals at high risk of exposure. However, the vaccine is not advised for pregnant individuals or those who are immunocompromised, including people with active cancer, transplant recipients, and those with poorly controlled HIV (CD4 cell count <200 cells/µL).
The Global Advisory Committee on Vaccine Safety reviewed updated safety data on September 20, 2024, and emphasized the need for healthcare workers to receive training on the correct use of bifurcated needles to prevent injuries and adverse effects.
Continued Efforts and Monitoring
WHO underscores the importance of collecting data on vaccine safety and efficacy, particularly as new virus strains emerge and epidemiological patterns shift. Collaboration with manufacturers, global partners, and countries remains central to ensuring equitable access to life-saving vaccines.
This announcement follows WHO’s prequalification of the Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN) vaccine on September 13, 2024, and its expanded use approval for individuals aged 12 years and older on October 8, 2024.
