Mpox vaccine is safe and generates a robust antibody response in adolescents
October 16, 2024
An NIH-funded clinical trial found the mpox vaccine (MVA-BN) safe and effective in adolescents aged 12-17, generating antibody responses equivalent to adults. This is crucial as adolescents are affected by the current Clade I mpox outbreak, particularly in Africa. The study compared outcomes between adolescents and adults aged 18-50. While the vaccine was well-tolerated, dizziness was more common in adolescents. These findings support the vaccine's use in adolescents, addressing a critical need in mpox-affected areas. Researchers emphasize the importance of extending studies to younger children to protect all vulnerable populations.
A National Institutes of Health (NIH)-funded clinical trial has revealed promising results for the mpox vaccine in adolescents. The study, presented at IDWeek2024 in Los Angeles, found that the modified vaccinia Ankara-Bavarian Nordic (MVA-BN) vaccine is safe and generates an antibody response in adolescents aged 12-17 that is equivalent to that seen in adults.
This research is particularly timely given the current Clade I mpox outbreak affecting adolescents and children in the Democratic Republic of the Congo (DRC) and other African countries. Mpox, first recorded in humans in 1970 in the DRC, exists in two clades: Clade I, endemic to Central Africa and potentially severe, and Clade II, endemic to West Africa and generally milder.
The NIAID-sponsored mid-stage study compared the vaccine's effects in adolescents to those in adults aged 18-50. Key findings from the interim analysis include:
1. Equivalent antibody levels in adolescents and adults two weeks after the second dose.
2. Good tolerability through 210 days after the second dose.
3. Comparable overall frequency of adverse events between study groups.
4. Higher incidence of dizziness in adolescents, similar to reactions seen with other vaccines in this age group.
These results are significant for several reasons:
- They support the vaccine's safety and efficacy in adolescents, addressing a critical gap in mpox prevention.
- The findings are relevant not only to the U.S. but to all areas affected by mpox.
- They pave the way for potential vaccine approval for individuals under 18.
The study team emphasizes the need to extend this research to younger children, aiming to protect all populations vulnerable to mpox. This is particularly crucial given that immunocompromised individuals, children, and pregnant people are at higher risk of severe mpox, regardless of the virus clade.
As the global community continues to grapple with mpox outbreaks, this study represents a significant step forward in expanding protective measures to younger populations.