Ring of Hope: New Vaccine Rounds Up Ebola

Courtesy Photo | When Ebola virus disease (EVD) reared its head in May in the Congo, the world was armed with the rVSV-ZEBOV vaccine thanks to interagency collaboration efforts by the Defense Threat Reduction Agency’s Chemical and Biological Technologies Department.  

FORT BELVOIR, VIRGINIA, UNITED STATES

10.15.2018

Courtesy Story

Defense Threat Reduction Agency's Chemical and Biological Technologies Department

The world watched as the 2014 Ebola outbreak ravaged West Africa. While several medical countermeasures were in development, they were not ready to conquer the deadly disease which infected over 28,000, claimed more than 11,000 lives, and sparked fears of a global pandemic. The next time would be different. When Ebola virus disease (EVD) reared its head in May in the Congo, the world was armed with the rVSV-ZEBOV vaccine thanks to interagency collaboration efforts by the Defense Threat Reduction Agency’s Chemical and Biological Technologies Department.

Initiated by the Ministry of Health and Population (MoHP) of the Congo and approved under Emergency Use Authorization by the U.S. Food and Drug Administration, health officials implemented ring vaccinations. Ring vaccinations control an outbreak by inoculating and monitoring a ring of people around each infected individual. The idea is to form a buffer of immune individuals to prevent the spread of the disease. Using the experimental rVSV-ZEBOV vaccine, this is the first time in the history of the Congo that vaccination was an integral part of the government’s response plan to an Ebola outbreak.

In July 2018, MoHP declared another Ebola outbreak in North Kivu province of the Congo. Once again, the MoHP implemented the same ring vaccination strategy to contain the outbreak. What most people do not know, however, is that DTRA played a pivotal role in making this possible.

Since EVD was identified in 1976, researchers have attempted to develop effective vaccines. Recognizing the pandemic potential of this disease, DTRA has been actively working on the development of Ebola diagnostics, therapeutics and vaccines for more than a decade. Of these, rVSV-ZEBOV, which is based on a recombinant vesicular stomatitis virus (rVSV) vector expressing the Ebola virus glycoprotein, proved to be a promising candidate. rVSV-ZEBOV was originally developed by New Link Genetics and the Public Health Agency of Canada through funding from DTRA CB. DTRA-funded preclinical studies in non-human primates showed the vaccine offered protection against the virus when given as a single-injection.

This was a key factor in prompting Merck Vaccines, Inc. to acquire rights to the vaccine and accelerate its development. DTRA further facilitated the manufacturing and FDA filings required to begin safety and efficacy trials in humans in the United States, Europe and Africa. Initial trials showed the vaccine to be safe and immunogenic in humans. In December 2016, the World Health Organization (WHO) announced a two-year trial of rVSV-ZEBOV which appeared 100 percent effective in preventing the virus.

In 2014, DTRA personnel consulted with WHO on the design of the trials and have assisted in identifying clinical trial sites. DTRA identified and addressed potential risks of the rVSV-ZEBOV vaccine by designing and executing parallel non-clinical and clinical studies. The studies demonstrated the safety and potency of rVSV-ZEBOV in lab animals and volunteers.

DTRA’s effort also enabled dose selection and demonstrated manufacturability of this vaccine, which were contributing factors to trials in West Africa. These efforts resulted from close regulatory interactions with the FDA as well as governments, charitable organizations, international relief efforts and local authorities in Africa. They were critical in enabling the recent deployment and use of the rVSV-ZEBOV vaccine during the current outbreak in the Congo.

Encouraged by the promising results, DTRA continues to support the development of rVSV-ZEBOV with the transition partner, the Biomedical Advanced Research and Development Authority. In addition, DTRA is supporting the development of therapeutic drugs, advanced diagnostics and additional next-generation filovirus vaccines, such as the MARV (for Marburg virus) and SUDV (for Ebola Sudan virus), to provide advanced medical countermeasures for the public and our warfighters.

DTRA CB POC: David Hone, Ph.D.; [e-mail]

• Date Taken: 10.15.2018
• Date Posted: 10.15.2018 20:14
• Story ID: 296536
• Location: FORT BELVOIR, VIRGINIA, US