Merck's experimental Ebola shot gets set to fight deadly new outbreak in Congo

As the death toll mounts in a new Ebola outbreak in the Democratic Republic of Congo, health officials are preparing to deploy Merck & Co.'s experimental vaccine against the virus. The pharma giant revved up the development project amid a major Ebola breakout in 2014 and 2015.

The new outbreak—so far limited to remote areas in the Congo—started in early April, according to a Monday update from the World Health Organization. Of the 39 people infected, 19 have died, translating into a 49% fatality rate. The agency is working with Gavi, the Vaccine Alliance; Médecins Sans Frontières; and the DRC's Ministry of Health to introduce the shot in a ring vaccination approach, a WHO spokesperson confirmed Monday. 

But because Merck's Ebola shot hasn't yet won regulatory approval, officials must obtain an importation license, plus establish a "formal agreement on the research protocols," WHO spokesperson Tarik Jašarević told FiercePharma. 

Jašarević added that "all steps are finalized and approvals obtained," but that he couldn't predict when vaccinations will begin. In its update Monday, WHO said the outbreak is a high public health risk in the country, moderate regionally and low internationally. Cases have been documented near the Congo River, which could carry the virus to nearby countries.

RELATED: Merck's Ebola vaccine grabs FDA, EMA milestones in push toward licensure 

A Merck spokesperson said the company is working with WHO and MSF to introduce the vaccine, adding that thousands of shots are ready to go, with "4,300 doses of the investigational V920 vaccine prepositioned with the WHO in Geneva to support rapid deployment to the outbreak area." 

The company's own stockpile contains more than 300,000 emergency use dose equivalents, she said. The V920 vaccine was initially engineered by scientists from the Public Health Agency of Canada’s National Microbiology Laboratory and later licensed to a subsidiary of NewLink Genetics. In late 2014, as the Ebola outbreak in western Africa peaked, Merck licensed the candidate from NewLink Genetics, planning to accelerate development.

Under the ring vaccination approach, after an Ebola case is recorded health workers vaccinate anyone who might have interacted with the infected person, such as family members and their contacts.. Merck's shot demonstrated 100% efficacy in a previous phase 3 ring vaccination study. 

Healthcare workers and others who could encounter the virus will also be vaccinated as part of the outbreak response. Last month, WHO expert advisers on vaccination met and recommended that the shot be deployed under a ring vaccination strategy should an outbreak emerge. 

RELATED: Merck's Ebola vaccine candidate could see early action against new Congo outbreak 

Last year, an outbreak in the country spanned 42 days and claimed four lives, according to the WHO. Officials prepped the vaccine for potential use against that outbreak, but never deployed the shot. 

An Ebola outbreak in 2014 and 2015 killed more than 11,000 people in West Africa, leading to frustration and anger in the scientific community that a vaccine wasn't yet available. Zika followed a year later, making it even more clear that the current vaccine development system wasn't adequately addressing possible threats. 

Since then, governments, nonprofits and pharma companies have come together to form the Coalition for Epidemic Preparedness Innovations, an international group designed to prepare for potential epidemics before they happen. The group set the MERS-CoV, Lassa and Nipah viruses as its initial targets.  

Biotechs Themis and Inovio have picked up grants from the coalition to conduct vaccine research against Lassa and MERS.