WHO Approves Mpox Vaccine for Adults in Africa, Suggests Off-Label Use for Children Despite Limited Data
Key Insights
The WHO has prequalified Bavarian Nordic's MVA-BN vaccine for mpox (search), the first such approval, to aid procurement by international agencies.
While approved for adults, the WHO suggests the vaccine can be used off-label in children and pregnant women during outbreaks, despite limited clinical trial data in these groups.
Experts raise concerns about the safety profile in adults and the lack of efficacy and safety data in pediatric populations, urging caution.
The World Health Organization (WHO) has approved the first mpox (search) vaccine for use in adults, suggesting it can also be administered to babies, children, teens, and pregnant women if they are in outbreak settings where the benefits of vaccination outweigh the potential risks. This recommendation comes despite the limited clinical trial data on these populations.
WHO’s approval of Bavarian Nordic’s MVA-BN vaccine will facilitate its purchase by governments and international agencies like Gavi, the Vaccine Alliance, and UNICEF. The MVA-BN vaccine, marketed as Jynneos in the US, is a smallpox/mpox (search) vaccine.
WHO Assistant Director-General Yukiko Nakatani stated that the decision could help national regulatory authorities fast-track approvals, increasing access to quality-assured mpox (search) vaccine products.
Concerns Over Pediatric Use
Children’s Health Defense Chief Scientific Officer Brian Hooker criticized the WHO’s approval of the vaccine for infants and children in Africa, calling it a train wreck in the making. He noted the abysmal safety profile in adults (up to 2.1% serious cardiac events in clinical trials) and the lack of adequate testing for efficacy or safety in pediatric populations.
"In other words, the WHO has no idea whether it will work nor do they know how much damage it will do. The WHO has again abandoned good public health principles and waved their magic vaccine wand on the mpox (search) outbreak," Hooker told The Defender.
Broader Public Health Issues
Dr. David Bell, a public health physician and biotech consultant, also criticized the WHO for focusing on mpox (search) vaccines while neglecting broader public health issues in Africa. He pointed out that about 40,000 children have died from malaria in the Democratic Republic of Congo (DRC) this year, with similar numbers succumbing to malnutrition, tuberculosis, and HIV/AIDS.
Bell, a former medical officer and scientist at the WHO, explained that the focus on rarer diseases like mpox (search) is more lucrative for the industry feeding off the WHO’s misinformation regarding rapidly rising pandemic risk. He suggested a return to impactful public health measures addressing the underlying causes of diseases of poverty, rather than merely treating symptoms with Western-developed commodities.
WHO's Stance and Available Data
In its press release, the WHO stated that the MVA-BN vaccine can be administered to adults over 18 as a two-dose injection four weeks apart but can also be given as a single dose in supply-constrained outbreak situations. The agency acknowledged that while MVA-BN is not currently licensed for persons under 18 years of age, it may be used off-label in infants, children, adolescents, and pregnant and immunocompromised people.
The WHO Strategic Advisory Group of Experts on Immunization noted that MVA-BN has not been specifically studied in clinical trials in children. However, they cited data from five published studies on MVA-BN as a viral vector platform for the prevention of Ebola virus disease (search) (EVD), with a total population of 52,229 children, supporting the favorable safety profile of the product.
A study published in the BMJ presented results on MVA-BN’s effectiveness in adult males but did not include data on children or pregnant women. In 2023, researchers funded by the UK Health Security Agency reported that a single dose of MVA-BN was well-tolerated in 87 children, but larger studies were needed to fully assess the shot’s safety and efficacy in children.
Regulatory Context
The WHO’s process for granting a drug prequalification approval for emergency use listing requires drugmakers to commit to continue generating missing information to fulfill prequalification requirements. The US Food and Drug Administration (FDA) granted emergency use authorization for the vaccine in individuals less than 18 years of age determined to be at high risk for monkeypox infection in 2022. Jynneos has been licensed for use in US adults since 2019.
The Centers for Disease Prevention and Control (CDC) states that while teens and children at risk for mpox (search) can receive Jynneos, it is not recommended for babies under six months. The CDC also says Jynneos can be given to pregnant or breastfeeding women, noting that animal studies haven’t shown any harm to developing fetuses when the vaccine was given to pregnant animals.