Public Release: 

Scientists report on trial of early-generation Ebola, Marburg vaccine candidates

NIH-sponsored trial in Uganda informed development of current NIAID/GSK vaccine candidate

NIH/National Institute of Allergy and Infectious Diseases


Results of an early-stage clinical trial of two experimental vaccines against Ebola and Marburg viruses--the first to be completed in an African country--showed that they were safe and induced immune responses in healthy Ugandan adult volunteers. Developed by researchers at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, the experimental vaccines (called DNA vaccines) were predecessors to a next-generation candidate vaccine, called the NIAID/GSK Ebola vaccine, which is currently in clinical development. The NIAID/GSK vaccine incorporates Ebola gene segments into a carrier derived from a chimpanzee adenovirus. It is being tested in several Phase 1 clinical trials around the world, with larger trials planned for early 2015.

Overall, the immune responses in the Ugandan volunteers were similar to those reported in a trial of these same DNA vaccines that enrolled participants in the United States in 2008. This is important, the researchers noted, because geographically disparate populations can sometimes have differing immune responses to the same vaccine. That North American and East African volunteers responded similarly to the experimental Ebola and Marburg vaccines is encouraging, they added, and information gained from this trial contributed to accelerated development of the current NIAID/GSK Ebola candidate vaccine.

The Ugandan trial began enrolling volunteers at Makerere University Walter Reed Project, Kampala, in 2009. A total of 108 people enrolled in the trial; 18 people received placebo injections and three groups (30 volunteers in each) received Ebola vaccine, Marburg vaccine or both. Participants received three injections spaced over eight weeks and all volunteers were followed for two years after enrollment. Antibody responses in all vaccine groups peaked at four weeks after the third inoculation. Antibodies against the Zaire stain of Ebola virus, the strain causing the current Ebola outbreak in West Africa, were seen in 17 volunteers who received the Ebola vaccine alone and in 14 of those who received both vaccines. Researchers also detected responses of the T-cell arm of the immune system in many of the volunteers. T-cells are believed to play an important role in protection against Ebola infection. Both vaccines were well-tolerated.



H Kibuuka et al. Safety and immunogenicity of Ebola virus and Marburg virus glycoprotein DNA vaccines assessed separately and concomitantly healthy Ugandan adults: a phase 1B randomised, double-blind, placebo-controlled clinical trial. The Lancet DOI: 10.1016/S0140-6736(14)62385-0 (2014).


NIAID Director Anthony S. Fauci, M.D., and Julie E. Ledgerwood, D.O., Vaccine Research Center, NIAID, are available to comment on this research.


To schedule interviews, please contact the NIAID Office of Communications, (301) 402-1663,

The identifier for this study is NTC00997607.

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 Web site at

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


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.