Introduction

In a groundbreaking move, Bavarian Nordic is embarking on a crucial trial of its mpox vaccine, Jynneos (MVA-BN), specifically aimed at protecting two of the most vulnerable groups—pregnant and breastfeeding women, as well as infants. This trial, named PregInPoxVac, will evaluate the safety and effectiveness of the vaccine in these populations, amidst a concerning mpox outbreak that has been identified by the World Health Organization (WHO) as a public health emergency.

Trial Overview

The Phase III trial will enlist approximately 350 pregnant women and 250 infants aged two years and under, and it is set to take place in the Boende territory of the Democratic Republic of Congo (DRC)—a region heavily impacted by the mpox outbreak. It is anticipated to commence early next year, aiming to gather critical data over a 12-month assessment period.

What's In Store for Participants?

In the first phase of the trial, pregnant women will receive two doses of the Jynneos vaccine either before or after giving birth. Researchers will closely monitor the transmission of maternal antibodies through blood samples and breast milk to their newborns, offering insight into the vaccine’s protective benefits. The second phase will involve administering either a full or half dose of the vaccine to infants aged six to 24 months. This data could potentially widen access to the mpox vaccine for these high-risk groups, who currently lack eligibility for vaccination.

Responding to a Growing Need

Bavarian Nordic's vaccine is the only WHO-prequalified mpox vaccine available for healthy adults and adolescents. With pregnant women and infants facing an elevated risk of severe complications from mpox infection, this trial aims to fill an urgent gap in public health response. Dr. Nicole Lurie, Executive Director of Preparedness and Response at the Coalition for Epidemic Preparedness Innovations (CEPI), emphasized the necessity of this research: "Until more data is available about the vaccine's safety and immunogenicity for these populations, their access remains limited."

Funding and Sponsorship

This pivotal study is not funded solely by Bavarian Nordic; it is also receiving investment from CEPI and Global Health EDCTP3, with the University of Antwerp spearheading the sponsorship efforts and the University of Kinshasa taking charge as the Scientific Project Leader. Bavarian Nordic will provide the necessary Jynneos doses for the trial.

Broader Implications on Public Health

Alongside this trial, CEPI is backing two additional studies of Bavarian Nordic’s mpox vaccine across Africa. These complementary studies aim to gather valuable evidence regarding vaccine efficacy within African demographics, which could significantly influence future vaccination strategies and pave the way for expedited regulatory approvals in areas heavily impacted by mpox.

Moreover, Bavarian Nordic is also conducting a Phase II trial (NCT06549530) that compares the immune responses in children aged two to under 12 years with those in adults aged 18-50 years, alongside ongoing trials that have indicated equivalent safety and antibody responses in teenagers compared to adults.

Conclusion

As this remarkable trial unfolds, it promises not only to bolster vaccine access for the most vulnerable but also to significantly enhance global health strategies in combating mpox and similar outbreaks. Stay tuned for more updates as this story develops!