An Ebola vaccine that shows immense potential has been sitting on a shelf for 15 years, sidelined by a lack of financial backing and commercial viability. Developed by Thomas Geisbert, an immunology professor at the University of Texas Medical Branch, the vaccine uses rVSV technology and has proven highly effective in protecting primates. Despite these results, it has never reached human trials because the market for an Ebola vaccine was perceived as unprofitable.
The Defense Origins
Thomas Geisbert began his research in the early 2000s under a US Army-funded defense project, intended to address fears that Ebola could be utilized as a biological weapon. By 2003, he achieved a significant milestone, protecting monkeys with a single injection. By 2009, he had even successfully tested a blend of vaccines against several Ebola strains known to affect humans.
The Barrier of Profit
Large pharmaceutical companies showed little interest in the candidate for years. During the 2013 to 2016 Ebola epidemic, Merck developed the Ervebo vaccine, which benefited from Thomas Geisbert’s foundational research. While Ervebo became a success for the Zaire strain, the Bundibugyo strain was largely ignored due to its perceived lower fatality rates, despite causing localized outbreaks.
Current Efforts and Obstacles
The urgency to address the Bundibugyo strain has only recently increased due to the scale of the current outbreak in Central and East Africa. A 2023 study confirmed that the vaccine could protect monkeys even after exposure, a critical factor for ring vaccination strategies. Now, the Coalition for Epidemic Preparedness Innovations has pledged up to $3.2 million to jumpstart the manufacturing and testing required for human trials, with the International AIDS Vaccine Initiative overseeing production. Despite this, challenges remain, including difficulties in accessing live virus samples and potential genetic variations that could impact the vaccine's performance.
