Human Testing on Ebola Vaccine Will Begin Next Week

Work on a vaccine to treat patients infected with the Ebola virus has been accelerated, as the scope of the outbreak is expected to grow to unprecedented levels.

The World Health Organization (WHO) said today that the Ebola virus could infect more than 20,000 people in West Africa before the outbreak is brought under control, according to a report in the New York Times. To date, the virus has killed more than 1500 people with just over 3000 confirmed and suspected cases in the countries of Guinea, Liberia, Sierra Leone, and Nigeria, according to the WHO.

With the scale of the outbreak expected to reach alarming heights, efforts to evaluate a vaccine have been fast-tracked by several different groups, most notably of which include a collaboration on a vaccine by the National Institutes of Health (NIH) and GlaxoSmithKline (GSK) that is expected to begin human safety trials as early as next week.

“There is an urgent need for a protective Ebola vaccine, and it is important to establish that a vaccine is safe and spurs the immune system to react in a way necessary to protect against infection,” said Anthony S. Fauci, MD, director of the NIH’s National Institute of Allergy and Infectious Diseases (NIAID), in a press release. “The NIH is playing a key role in accelerating the development and testing of investigational Ebola vaccines.”

The study will launch the first of several Phase I clinical trials to evaluate the vaccine, in addition to an experimental Ebola drug developed by the Public Health Agency of Canada licensed to NewLink Genetics Corp, which is also expected to begin this fall. The trials will be conducted in healthy adults who are not infected with the virus in order to investigate whether the drugs are safe and can generate an adequate immune response.

The candidate drug developed by the NIH and GSK is based on an attenuated strain of a chimpanzee cold virus, which is used as a carrier to deliver benign genetic material derived from a strain of the Ebola virus.

The material contained in the vaccine, however, cannot cause an infection. Rather, the drug delivers the viral genetic material to human cells without further replication, allowing the recipient’s cells to express a protein that generates an immune response.

A study arm in the United Kingdom will include 60 healthy volunteers, while separate arms in Gambia and Mali will each involve 40 volunteers who will be split into groups of 20. Those groups will receive different doses of the vaccine to evaluate the best dosage amount in terms of safety and efficacy.

In addition to accelerating the process, the multi-trial approach will take into account differences between the European and West African populations that might impact safety and immune response.

The Phase I trials are anticipated to conclude by the end the year, while deployment of the drug could be fast-tracked if the vaccine is determined to be safe and immunogenic, the NIH said.

“The tragic events unfolding in Africa demand an urgent response,” said Adrian Hill, director of the Jenner Institute at the University of Oxford, in a press release. “In recent years, similar investigational vaccines have safely immunized infants and adults against a range of diseases including malaria, HIV, and hepatitis C. We, and all our partners on this project, are optimistic that this candidate vaccine may prove useful against Ebola.”