An interdisciplinary team of researchers that included investigators from the University of Texas Medical Branch (UTMB) in Galveston, Texas, and Profectus BioSciences, Inc., a clinical-stage vaccine company developing novel vaccines for the treatment and prevention of infectious diseases, recently showed that a single dose of vaccine administered using the company’s VesiculoVax™ technology protects non-human primates against the “Makona” strain of Ebola virus (previously referred to as the Ebola Guinea strain) that is responsible for the current Ebola outbreak in West Africa. The study, entitled, “Single-Dose Attenuated VesiculoVax™ Vaccines Protect Primates Against Ebola Makona Virus,” was published in the latest issue of Nature.
The study was conducted in the lab of Dr. Thomas W Geisbert, PhD, Professor, Microbiology & Immunology, UTMB, who has been studying the Ebola virus for close to 3 decades. The lab is a Biosafety-level 4 (BSL-4) facility located at UTMB’s Galveston National Laboratory (GNL),with a focus on the pathogenesis of emerging and re-emerging viruses that require BSL-4 containment (Ebola, Marburg, and Lassa Fever viruses) and on the development of countermeasures, such as vaccines, against these viruses.
Dr. Geisbert and colleagues vaccinated 8 rhesus macaque monkeys with 2 versions of the vaccine 28 days before injecting the monkeys with the Makona strain of Ebola from Guinea. They compared these 8 monkeys with 2 unvaccinated macaques’ for disease diagnosis and progression. The vaccinated monkeys showed no signs of viral illness, and blood tests showed zero traces of the virus; whereas the unvaccinated control monkeys died from the virus on days 7 and 8.
In a company press release, John Eldridge, PhD, Chief Scientific Officer of Profectus, explained the importance of the study’s findings, “A key goal in efforts to address the 2014-2015 outbreak of the highly lethal Zaire Ebola virus has been to develop a preventive vaccine that rapidly confers protection in a single administration. This is the first demonstration of a vaccine that is able to rapidly confer single-dose protection against the current Makona strain of Zaire Ebola virus that is responsible for more than 10,000 deaths in the ongoing epidemic in West Africa. We are grateful to the Geisbert laboratory at UTMB for its unrestricted collaboration, and we are excited about the potential of our vaccine to combat the current outbreak. We look forward to continued rapid progress to advance this vaccine—along with our trivalent vaccine for protection against all Ebola and Marburg viruses—into human clinical trials.”
Dr. Geisbert, shared his collaborators enthusiasm, “These findings may pave the way for the identification and manufacture of safer, single dose, high efficiency vaccines to combat current and future Ebola outbreaks. We are excited at the possibility of helping develop a way to stop this deadly disease. We have a lot of more work to accomplish but it’s important to note that this is a big step.”