WHO adds LC16m8 mpox vaccine to Emergency Use Listing

Today’s move is particularly relevant as the Government of Japan has announced that it will donate 3.05 million doses of the LC16m8 vaccine, along with specialized inoculation needles, to the Democratic Republic of the Congo. This is the largest donation package announced to date in response to the current mpox emergency.

LC16m8 is a vaccine developed and manufactured by KM Biologics in Japan. The Technical Advisory Group (TAG) for EUL of vaccines convened to discuss the outcome of the LC16m8 vaccine review, including the product and programmatic suitability assessments. The TAG recommended the vaccine for use in individuals over one year of age as a single dose vaccine, via a multiple puncture technique using a bifurcated needle.

“WHO emergency use listing of the LC16m8 vaccine against mpox marks a significant step in our response to the current emergency, providing a new option to protect all populations, including children,” said Dr Yukiko Nakatani, WHO Assistant Director-General for Access to Medicines and Health Products. “Vaccines are one of the important tools to help contain the outbreak as part of a comprehensive response strategy that also includes improved testing and diagnosis, treatment and care, infection prevention control, and engagement and education within affected communities.”

WHO’s assessment for EUL is based on information submitted by the manufacturer and review by the Pharmaceuticals and Medical Devices Agency (PMDA), the Japanese regulatory agency of record for this vaccine. The LC16m8 vaccine has been used in Japan during previous mpox outbreaks and was shown to be safe and effective, including in people with well-controlled HIV.

The WHO Strategic Advisory Group of Experts (SAGE) on Immunization reviewed available evidence and recommended the use of LC16m8 vaccine in outbreak settings in children and others with a documented high-risk of exposure to mpox.

However, minimally replicating vaccines, such as LC16m8, should not be used during pregnancy and in people who are immunocompromised. Immunocompromised persons include those with active cancer, transplant recipients, immunodeficiency, and active treatment with immunosuppressive agents. They also include people living with HIV with a current CD4 cell count of <200 cells µl.

The Global Advisory Committee on Vaccine Safety reviewed the updated safety data on LC16m8 on 20 September 2024 and recommended that healthcare workers are provided with training on the use of bifurcated needles to prevent injuries and adverse effects. In light of the changing epidemiology and emergence of new virus strains, it remains important to collect as much data as possible on vaccine safety and effectiveness in different contexts.

WHO continues to work closely with manufacturers, global partners and countries to ensure the availability and administration of safe and effective life-saving products.

On 13 September 2024, WHO prequalified the Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN) vaccine and expanded its indication to include use in individuals aged 12 years and older on 8 October 2024.

WHO Prequalification (PQ) and Emergency Use Listing (EUL) are mechanisms used to evaluate quality, safety and efficacy of medical products, such as vaccines, diagnostics and medicines, and product suitability for use in the contexts of low- and middle-income countries. Products receiving PQ or EUL support decision-making for international, regional and country procurement by UN and partner procurement agencies and Member States. PQ is based on the review of full set of quality, safety and efficacy data on medical products, including risk management plan and programmatic suitability. EUL is a risk benefit assessment to address urgent demands during public health emergencies based on available limited data where the benefits outweigh the risks.