NIH to Begin Ebola Vaccine Trial in Humans

Troy Brown, RN

August 28, 2014

Early human trials of an investigational vaccine to prevent Ebola virus disease will begin next week, according to the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health (NIH).

"More than 1500 suspected and confirmed deaths from Ebola infection have been reported in Guinea, Liberia, Nigeria, and Sierra Leone since the outbreak was first reported in March of this year," Francis S. Collins, MD, PhD, director, NIH, Bethesda, Maryland, said in a press briefing. "Working with our collaborators, NIH has responded by implementing extraordinary measures to accelerate the pace of vaccine clinical trials in order to respond to this devastating West African outbreak."

The early-stage trial will evaluate the vaccine's safety and immunogenicity and is the first of several phase 1 clinical trials of Ebola vaccine candidates expected to begin in the coming months. "The rapidly evolving and currently uncontrolled outbreak of Ebola virus disease in West a public health emergency that demands an all-hands-on-deck response," Anthony S. Fauci, MD, director, NIAID, NIH, Bethesda, said in the briefing. "In this regard, we have accelerated the timeline for testing experimental Ebola virus vaccines that we have been developing for several years."

Genetic Material From Multiple Ebola Viruses

The experimental vaccine was codeveloped by the NIAID and GlaxoSmithKline. Testing of the vaccine will be conducted at the NIH Clinical Center in Bethesda.

The bivalent vaccine uses a chimpanzee adenovirus (chimp adenovirus type 3) as a vector to administer segments of genetic material obtained from the Zaire Ebola and Sudan Ebola virus species. The Zaire species is responsible for the current outbreak.

The Ebola gene the vaccine carries enables the cells of the vaccine recipient to express a single Ebola protein, which stimulates an immune response in the recipient but will not cause infection, the NIH explained in a statement. "The experimental NIAID/[GlaxoSmithKline] vaccine performed extremely well in protecting nonhuman primates from Ebola infection," Dr. Fauci noted.

The phase 1 clinical trial (VRC 207) will be conducted among 2 groups of 10 healthy adults aged 18 to 20 years, based on expedited US Food and Drug Administration review and approval. The first group will be given an intramuscular injection of the experimental vaccine, and the second group will be given an injection of a higher dose of the same vaccine. The trial will use a staged enrollment plan in which 3 participants will receive the vaccine and undergo 3 days of follow-up to establish safety before the remaining participants receive the vaccine. Clinical staff and the study protocol team will review patient data daily and weekly, and clinical staff will evaluate participants 9 times during a 48-week period.

In parallel, NIH is working with a British-based international consortium including the Wellcome Trust and the Medical Research Council and Department for International Development to test the vaccine candidate among healthy adult volunteers both in the United Kingdom and in Gambia (after approval from the relevant authorities) and Mali.

The Centers for Disease Control and Prevention has begun discussions with Nigerian Ministry of Health officials about conducting a phase 1 safety study of the vaccine among healthy adults there.

The first reports on the vaccine's safety and efficacy are expected in late 2014, Dr. Fauci explained in the briefing.

The VRC 207 trial will also test a monovalent version of the same vaccine that contains genetic material from the Zaire Ebola species only. This trial will also study that vaccine in 20 healthy adults and is expected to begin in October. It will take place at the NIH Clinical Center and possibly another US location.

The NIH is also working at the same time with the international consortium to test the monovalent vaccine candidate among 60 healthy volunteers in the United Kingdom and 40 healthy volunteers in Mali. The vaccine is also expected to undergo testing among 40 healthy volunteers in Gambia "after approval from the relevant authorities," according to the NIH statement. The trial in the United Kingdom is expected to begin in mid-September after ethical and regulatory approval.

This fall, testing is expected to begin on an experimental vaccine that was developed by the Public Health Agency of Canada and is licensed to NewLink Genetics Corporation, a biopharmaceutical company in Ames, Iowa.

Public Health Measures Critical

"We know that the spread of Ebola infection can be prevented through public health measures including good infection control practices, patient isolation, contact tracing, quarantine, and the correct use of personal protective equipment," Dr. Fauci said. "In the current situation in West Africa, these validated public health measures must be the main focus of current efforts to contain this disease. However, a safe and effective Ebola vaccine would be a critically important addition to our prevention toolkit for Ebola virus disease," Dr. Fauci explained.


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