QUESTIONS AND ANSWERS
PREVAIL Phase 2/3 Clinical Trial of Investigational Ebola Vaccines
February 2, 2015
PREVAIL stands for Partnership for Research on Ebola Vaccines in Liberia. It is a Phase 2/3 clinical trial designed to evaluate the safety and efficacy of two investigational vaccines intended to prevent Ebola virus infection: the NIAID/GSK investigational Ebola vaccine and the VSV-ZEBOV investigational Ebola vaccine. The trial is being led by a recently formed Liberia-U.S. clinical research partnership and is sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH).
The trial is expected to enroll approximately 27,000 healthy men and women aged 18 years and older. Women who are pregnant or breastfeeding cannot enroll, nor can men and women who have recovered from Ebola infection. In addition to seeking healthy adults, the trial will seek to enroll people who are at particular risk for Ebola infection, including health care workers, individuals living in communities with ongoing transmission, contact tracers, members of burial teams and ambulance drivers.
The VSV-ZEBOV Ebola vaccine candidate is based in part on a genetically engineered version of vesicular stomatitis virus (VSV), an animal virus that primarily affects cattle. Human VSV infections are rare and generally produce three to four days of mild illness. In the VSV-ZEBOV investigational vaccine, the gene for the outer protein of the vesicular stomatitis virus has been replaced with a segment of the gene for the outer protein of the Zaire Ebola virus species.
No. The Ebola genetic material contained in the experimental vaccines cannot cause someone to become infected with Ebola because it is only a small piece that by itself is not infectious.
NIAID conducts and supports research—at NIH, throughout the United States, and worldwide—to study the causes of
infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID website.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S.
Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research,
and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.
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Last Updated February 02, 2015
Last Reviewed February 02, 2015