WHO approves MVA-BN as first prequalified vaccine against mpox

ISLAMABAD: The World Health Organisation (WHO) has approved the MVA-BN vaccine as the first vaccine against mpox to be added to its prequalification list.

The prequalification approval is expected to facilitate timely and increased access to this vital product in communities with urgent needs, to reduce transmission and help contain the outbreak. WHO’s assessment for prequalification is based on information submitted by the manufacturer, Bavarian Nordic A/S, and review by the European Medicines Agency, the regulatory agency of record for this vaccine.

“This first prequalification of a vaccine against mpox is an important step in our fight against the disease, both in the context of the current outbreaks in Africa and in future,” said WHO Director-General Dr Tedros Adhanom Ghebreyesus. “We now need urgent scale up in procurement, donations and rollout to ensure equitable access to vaccines where they are needed most, alongside other public health tools, to prevent infections, stop transmission and save lives.” The MVA-BN vaccine can be administered in people over 18 years of age as a 2-dose injection given 4 weeks apart. After prior cold storage, the vaccine can be kept at 2–8°C for up to 8 weeks.

“The WHO prequalification of the MVA-BN vaccine will help accelerate ongoing procurement of the mpox vaccines by governments and international agencies such as Gavi and Unicef to help communities on the frontlines of the ongoing emergency in Africa and beyond,” said Dr Yukiko Nakatani, WHO Assistant Director-General for Access to Medicines and Health Products. “The decision can also help national regulatory authorities to fast-track approvals, ultimately increasing access to quality-assured mpox vaccine products.”

The WHO Strategic Advisory Group of Experts (SAGE) on immunisation reviewed all evidence and recommended MVA-BN vaccine in the context of the mpox outbreak for persons at high risk of exposure. While MVA-BN is currently not licensed for persons under 18 years, this vaccine may be used “off-label” in infants, children and adolescents, and in pregnant and immune-compromised people. This means vaccine use is recommended in outbreak settings where the benefits of vaccination outweigh the potential risks.

WHO also recommends single-dose use in supply-constrained outbreak situations. WHO emphasizes the need to collect further data on vaccine safety and effectiveness in these circumstances. Available data shows that a single-dose MVA-BN vaccine given before exposure has an estimated 76% effectiveness in protecting people against mpox, with the 2-dose schedule achieving an estimated 82% effectiveness. Vaccination after exposure is less effective than pre-exposure vaccination.