Promising results in Ebola vaccine safety trial

The candidate vaccine is being jointly developed by the National Institute of Allergy and Infectious Diseases (NIAID) - one of the National Institutes of Health (NIH) - and the global health care company GlaxoSmithKline (GSK).

The first participant, a 39-year-old woman, receives a dose of the experimental Ebola vaccine at the NIH Clinical Center.
Image credit: NIAIDThe candidate vaccine is being jointly developed by the National Institute of Allergy and Infectious Diseases (NIAID) - one of the National Institutes of Health (NIH) - and the global health care company GlaxoSmithKline (GSK).

A preliminary report on the VRC 207 trial, which tested the safety of the vaccine in 20 healthy adults at the NIH Clinical Center in Bethesda, MD, is published in the New England Journal of Medicine.

The unprecedented scale of the current Ebola epidemic in West Africa has prompted intense efforts to develop safe and effective vaccines, not only to help stem the current spread, but also to prevent future outbreaks.

"Based on these positive results from the first human trial of this candidate vaccine, we are continuing our accelerated plan for larger trials to determine if the vaccine is efficacious in preventing Ebola infection," says NIAID Director Dr. Anthony S. Fauci.

Vaccine contains genetic material from two strains of Ebola

The vaccine comprises a harmless "carrier virus" - which causes a common cold in chimpanzees and does not cause illness in humans - and genetic material from two strains of Ebola virus: the Sudan strain and the Zaire strain.

The vaccine does not contain Ebola virus and cannot cause Ebola disease, say the developers.

In total, 20 healthy people aged 18-50 volunteered for the trial. Of these, 10 people received a low dose, and 10 received a high dose of the vaccine via intramuscular injection.

The researchers tested the participants' blood 2 weeks and 4 weeks later to find out whether the vaccine had caused their immune systems to produce antibodies to Ebola.

The results showed that all the participants had produced anti-Ebola antibodies at the 4-week point. The highest levels of antibodies were found in the volunteers who received the higher dose of vaccine.