UTMB research advances Bundibugyo Ebola vaccine data

As global health officials respond to a growing outbreak of the Bundibugyo Ebola virus in the Democratic Republic of the Congo, researchers at The University of Texas Medical Branch (UTMB) have advanced efforts to develop a vaccine specifically targeting the virus.

The vaccine candidate was developed in the lab of Thomas Geisbert, PhD, a professor in the Department of Microbiology and Immunology at UTMB, with crucial earlier work by Andrea Marzi, PhD, and Dr. Heinz Feldman and their team at the Laboratory of Virology, National Institute for Allergy and Infectious Diseases.

It has demonstrated promising protection against the Bundibugyo Ebola virus in early efficacy assessments. The findings show the vaccine candidate protected nonhuman primates and laid the groundwork for potential future clinical development.

Geisbert said the current outbreak underscores the urgent need for vaccines tailored to less common Ebola species.

"Bundibugyo Ebola virus outbreaks are rare, but when they occur, they can be devastating," Geisbert said. "Most licensed Ebola vaccines were designed to target the Zaire Ebola species, which caused the large West Africa outbreak from 2013 to 2016. We need countermeasures that address other Ebola viruses as well."

The World Health Organization recently prioritized the vaccine candidate for additional evaluation as the Democratic Republic of the Congo and neighboring countries work to contain the outbreak. While there are currently no approved vaccines or therapeutics specifically for the Bundibugyo Ebola virus, Geisbert said the research community has been preparing for this possibility for years.

The vaccine candidate uses a vesicular stomatitis virus, or VSV, platform - the same technology used in the licensed Ebola vaccine Ervebo. In pilot efficacy testing, the Bundibugyo-specific vaccine generated strong immune responses and protected vaccinated animals from disease.

Geisbert emphasized that high-consequence pathogens require sustained investment long before outbreaks occur.

"You can't wait until an outbreak starts to begin vaccine development," he said. "This work reflects years of preparation, collaboration, and high-containment research designed to ensure we have options ready when these events happen."

The vaccine candidate will require additional regulatory review and clinical testing for efficacy and safety. However, researchers say the existing data provide an important foundation for future outbreak response efforts.

"Our goal is to stay ahead of these viruses," Geisbert said. "Preparedness gives us the best chance to save lives when outbreaks emerge."