The scientists will try to formulate Oxford Vaccine Group (OVG)’s ‘chimpanzee adenovirus Oxford’ (ChAdOx) vector into Enesi’s ImplaVax technology, aiming to create a vaccine against the plague infection, caused by the bacterium Yersinia pestis.
Also known as the ‘Black Death’, the plague infection presents high mortality rate unless treated with antibiotics. During the 14th century, it caused more than 50 million deaths in Europe.
However, the threat posed by infection persists to this day; from 2010 to 2015, there were over 3,000 reported cases worldwide, including over 500 deaths, mainly in Africa, and an outbreak was reported in Madagascar in 2017.
The vaccines used for prevention of the plague have not been proven to be effective and safe, therefore, at present, there is no approved vaccine available in the US.
A spokesperson from Enesi told us the ChAdOx vector, created in the labs of University of Oxford, presents “very good immunogenicity” against the plague infection, and that the group at OVG has “excellent insight into vaccine development.”
For its part, Enesi’s ImplaVax technology uses a needle-free device to implant a solid dose of the drug under the skin and, according to Christine Rollier, associate professor of vaccinology at OVG, “[this] has the potential to generate improved immune responses”.
“Implants benefit from extended thermal stability, which can make a significant contribution to reducing the end-to-end cold chain logistical challenges and distribution costs,” she added.
In addition to this, ImplaVax is also “convenient to use, possible to stockpile and rapid to deploy,” the spokesperson from Enesi said.
“We think the combination of these attributes and the capabilities of the teams at OVG and Enesi will enable us to develop a viable plague vaccine,” the spokesperson added.
Enesi has already established multiple collaborations to develop ImplaVax-enabled vaccines for a range of infectious diseases and allergies.
Protection against bioterrorism
Last year, the US Food and Drug Administration announced the approval of a treatment for smallpox, stating it had encouraged the development, although there were no reported cases, due to the risk of a bioterrorism incident.
SIGA, the company involved, explained to us, at the time, that the US ordered and had delivered two million courses of the treatment to the Strategic National Stockpile, a repository of antibiotics, vaccines, and antitoxins that are held for use during public health emergencies.
The Yersinia pestis bacterium also has the potential of being used as a biological weapon, and it is rated by the US National Institute of Allergy and Infectious Diseases (NIAID) as a category A pathogen.
As stated by Enesi’s spokesperson, the company aims to develop the vaccine for use not only in outbreaks around the world but also for “building strategic stockpiles as part of government preparedness for rapid deployment in the event of a bioterrorism incident”.