In September 2024, WHO announced that the MVA-BN vaccine, manufactured by Bavarian Nordic, is the first vaccine against mpox to be put on the prequalification list. This approval is “expected to facilitate timely and increased access” to the vaccine in “communities with urgent need” amid the outbreak of mpox. The prequalification is based on information submitted by Bavarian Nordic and reviewed by the European Medicines Agency.
Recommended for use
WHO’s Strategic Advisory Group of Experts (SAGE) on Immunisation recommended the use of MVA-BN in an mpox outbreak context for persons at high risk of exposure. It can be administered in over-18s in two doses 4 weeks apart. After initial cold storage it can be kept between 2°C and 8°C for up to 8 weeks.
Although it is not currently licensed for persons under 18 years of age, the vaccine can be used “off-label” in infants, children, and adolescents, and in pregnant and immunocompromised people. This allows use in an outbreak after consideration of the potential risks in relation to the benefits of vaccination.
Data available to WHO reveal that a single-dose MVA-BN vaccine, administered before exposure, has an estimated 76% effectiveness in protecting against mpox; the two-dose schedule achieves an estimated 82% effectiveness. Post-exposure vaccination is less effective. Clinical studies have demonstrated a good safety profile and vaccine performance, which have been confirmed in real-world use during the global outbreak since 2022. However, WHO emphasises the need to collect “as much data as possible on vaccine safety and effectiveness in different contexts”.
An important step
Dr Tedros Adhanom Ghebreyesus, WHO Director-General, described this first prequalification as an “important step in our fight against the disease” with implications for current outbreaks and the future.
“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.”
WHO Assistant Director-General for Access to Medicines and Health Products, Dr Yukiko Nakatani, suggested that the prequalification will “help accelerate ongoing procurement” to help communities “on the frontlines of the ongoing emergency in Africa and beyond”.
“The decision can also help national regulatory authorities to fast-track approvals, ultimately increasing access to quality-assured mpox vaccine products.”
Dr Rogerio Gaspar, WHO Director for Regulation and Prequalification, commented that the findings of the product and programmatic suitability assessments are “particularly relevant in the context of the declaration of a public health emergency of international concern (PHEIC)”.
“We are progressing with prequalification and emergency use listing procedures with manufacturers of two other mpox vaccines: LC-16 and ACAM2000. We have also received 6 expressions of interest for mpox diagnostic products for emergency use listing so far.”
To explore the steps before, during, and after these approval processes in emergency contexts, join us at the Congress in Barcelona this October. Don’t forget to subscribe to our weekly newsletters here for regular updates.
