LONDON (TIP): The world’s first inhalable Ebola vaccine in development has proved highly successful in animal studies. Scientists from the University of Texas have confirmed that a potentially breathable, respiratory vaccine in development has been shown to provide long-term protection for nonhuman primates against the deadly Ebola virus. Results from a recent pre-clinical study represent the only proof to date that a single dose of a non-injectable vaccine platform for Ebola is long lasting, which could have significant global implications in controlling future outbreaks.

A breathable vaccine could surmount the logistical obstacles of storing, transporting and administering injectable vaccines in parts of Africa most afflicted by the virus. Professor Maria Croyle along with Dr Gary Kobinger at the National Microbiology Laboratory in Winnipeg will make the announcement on Nov 5. The Ebola virus is an often fatal illness that is spread among the human population via direct contact with blood or bodily fluids from an infected individual. The current Ebola outbreak in West Africa is the largest and most complex epidemic since the virus was first discovered in 1976, according to the World Health Organization. With a fatality rate currently as high as 70 percent, officials are declaring this outbreak a public health emergency of international concern.

Croyle worked over seven years to develop a respiratory formulation that improved survival of immunized nonhuman primates from 67% to 100% after challenge with 1,000 plaque forming units of Ebola Zaire 150 days after immunization. This improvement is statistically significant because only 50% of the primates given the vaccine by the standard method of intramuscular injection survived challenge. Although progress has been made in understanding the virus’ biology, no licensed vaccines or treatments currently exist, noted the researchers. “There is a desperate need for a vaccine that not only prevents the continued transmission from person to person, but also aids in controlling future incidences.

The main advantage of our vaccine platform over the others in clinical testing is the long-lasting protection after a single inhaled dose,” scientists said. They added “This is important since the longevity of other vaccines for Ebola that are currently being evaluated is not fully evaluated. Moreover, this immunization method is more attractive than an injectable vaccine given the costs associated with syringe distribution and needle safety and disposal”. The next stage of research for Croyle’s team is a phase I clinical trial that tests the effectiveness of their vaccine on human subjects. They will also further explore preliminary data they have collected for administration of the vaccine as a thin film under the tongue in non-human primates.