WHO approves first prequalified mpox vaccine 'MVA-BN'

• Vaccine's single dose before mpox exposure has 76% effectiveness.
• Data shows two doses found to increase vaccine's efficacy to 82%.
• WHO chief stresses boost in vaccine's procurement and roll out.

The World Health Organisation (WHO) has approved MVA-BN as the first pre-qualified vaccine against monkeypox virus, The News reported on Saturday.

"This first pre-qualification 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.

The development comes as the United Nations' health centric-body had declared the mpox outbreak as an "international health emergency" in July.

Vaccine development has been in focus in recent times with the WHO also allowing its partners Gavi and the United Nations International Children's Emergency Fund (Unicef) to buy mpox vaccines even before the UN's approval last month.

Traditionally, organisations like Gavi, an alliance which helps lower-income countries buy vaccines, can only start purchasing shots once they have approval from the WHO.

Two vaccines, made by Denmark's Bavarian Nordic BAVA.CO and Japan's KM Biologics, have already been approved by regulators around the world, including the United States and Japan, and have been in widespread use for mpox since 2022.

Around 1.2 million people have had Bavarian Nordic's vaccine in the United States alone.

It is to be noted that Pakistan has reported six mpox cases in 2024 and five since the outbreak was declared a public health emergency of international concern by the WHO.

The MVA-BN's pre-qualification 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 pre-qualification 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

"We now need urgent scale up in procurement, donations and roll-out to ensure equitable access to vaccines where they are needed most, alongside other public health tools, to prevent infections, stop transmission and save lives," remarked the WHO chief.

The vaccine — which can be stored at 2–8°C for up to 8 weeks after prior cold storage — can be administered in people over 18 years of age as a 2-dose injection given four weeks apart.

Available data showing that a single-dose MVA-BN vaccine given before exposure has an estimated 76% effectiveness in protecting people against mpox, with the two-dose schedule achieving an estimated 82% effectiveness.

Meanwhile, the WHO has also recommended single-dose use in supply-constrained outbreak situations.

Speaking on the vaccine's approval, WHO Assistant Director-General for Access to Medicines and Health Products Yukiko Nakatani said: "The WHO pre-qualification 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".

She also remarked that decision could 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 the 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 meaning that the vaccine's use is recommended in outbreak settings where the benefits of vaccination outweigh the potential risks.