Partnering Against Pandemics: Experimental Ebola Vaccine on Route to FDA Licensure

Courtesy Photo | Geographical distribution of the Ebola virus disease outbreak in the Democratic Republic of the Congo as of June 2017. Graphic courtesy of World Health Organization.  

FORT BELVOIR, VA, UNITED STATES

08.22.2017

Courtesy Story

Defense Threat Reduction Agency's Chemical and Biological Technologies Department

The 2014 Ebola epidemic in West Africa was unlike any other in modern times, spreading to tens of thousands of people across several countries. If the virus had spread farther, or had been used as a biological weapon, the results may have been catastrophic. The World Health Organization recently declared another Ebola outbreak in the Democratic Republic of the Congo (DRC), but this time the Defense Threat Reduction Agency’s Chemical and Biological Technologies Department and Merck are armed with VSV-ΔG-EBOV, an experimental Ebola vaccine has received breakthrough therapy designation from the Food and Drug Administration. A critical aspect of warfighter readiness is the ability to engage in threat environments. Without a viable Ebola vaccine, warfighters cannot safely operate in areas ravaged by an outbreak, potentially hindering mission success and humanitarian aid.

DRC health authorities approved the unlicensed vaccine for use in a ring trial in conjunction with the Ministry of Health and Doctors Without Borders should the current Ebola outbreak worsen. The VSV-ΔG-EBOV vaccine is a modified version of vesicular stomatitis virus (VSV), which normally causes disease in livestock and occasionally, a flu-like illness in humans. The Public Health Agency of Canada modified this virus to create a vaccine by replacing the surface glycol protein from VSV with that from Ebola Zaire. The modified virus is replication competent but doesn't cause illness in humans. DTRA, in partnership with the Joint Program Executive Office for Chemical and Biological Defense and the Biomedical Advanced Research and Development Authority, expedited the manufacturing and FDA filings required for the vaccine to begin human safety and efficacy trials in the United States, Europe and Africa. These efforts resulted in an initial safety trial conducted at Walter Reed Army Institute of Research, which showed the vaccine to be safe and immunogenic in humans. Merck then acquired the vaccine for further development and production.

The vaccine was selected for use in a Phase 3 ring vaccination trial in Guinea based on the previous animal and human studies which pinpointed a safe and effective dose, combined with the capability to manufacture an ample supply. Subsequently, interim results of this trail published in the Lancet show the VSV-ΔG-EBOV vaccine is between 70 and 100 percent effective in preventing Ebola virus disease in humans.

Presently, there are no FDA approved pre- or post-exposure Ebola interventions available in the event of a natural outbreak, laboratory accident or deliberate misuse. The progress and growing reliance on the VSV-ΔG-EBOV vaccine indicates that this product is on a fast track to meet FDA licensure requirements and be available to warfighters. Licensure of a safe and effective Ebola vaccine is necessary to ensure the health and readiness of warfighters operating in environments threatened by Ebola. For more information on the vaccine trial and results, please visit The Lancet article, “Efficacy and Effectiveness of an rVSV-Vectored Vaccine in Preventing Ebola Virus Disease: Final Results from the Guinea Ring Vaccination, Open- Label, Cluster-Randomised Trial (Ebola Ça Suffit!).”

POC: Revell Phillips, Ph.D.; [e-mail]

• Date Taken: 08.22.2017
• Date Posted: 08.22.2017 14:33
• Story ID: 245592
• Location: FORT BELVOIR, VA, US