Ebola vaccine (Etubics corporation)

Merck delivered hundreds of thousands of doses of its then-unapproved vaccine to the Democratic Republic of Congo to help to address the 2018 Ebola outbreak. When a deadly outbreak of the Ebola virus spread through the Democratic Republic of Congo in 2018, Merck’s then-unapproved vaccine was quickly deployed to help address the crisis and provide protection to hundreds of thousands of recipients. Now, four years after that epidemic ended, a new analysis offers a clearer picture on the vaccine’s real-world effectiveness. For the study, the researchers looked at data collected from Ebola treatment centers to gauge the real-world effectiveness of the vaccine during the 2018-20 outbreak in the DRC, according to an article published in The Lancet Infectious Diseases. The study, which is the first to evaluate the real-world effectiveness of "widespread use" of the vaccine, showed that Merck's shot was 84% effective against the virus in people who were infected 10 or more days after vaccination.The "test-negative analysis" determined the vaccine's effectiveness by weighing the likelihood of Ebola-positive patients being vaccinated or unvaccinated during the period. The study framework has also been used to weigh vaccine effectiveness in other viral diseases such as influenza and COVID-19, the study authors noted, as the usual standard of running randomized controlled trials can present ethical concerns in the context of a virus epidemic. Before this study, the only efficacy stats on Merck’s vaccine were estimated in a phase 3 study that utilized the ring vaccination strategy in a smaller number of participants. Ring vaccination is a viral mitigation strategy that involves vaccinating those in contact with someone with confirmed exposure.That study, which occurred during a massive outbreak in West Africa from 2014 to 2016, put the vaccine's efficacy rate at an estimated 100%. The real-world outcomes findings weren’t expected to match that perfect result, the authors of the new study noted.Merck's vaccine, branded as Ervebo, is recommended by the World Health Organization's (WHO's) Strategic Advisory Group of Experts on Immunization for those at risk of Ebola exposure during outbreaks. The shot was provided in the DRC during the 2018-20 epidemic through an expanded access framework. The vaccine won approval in Europe and the U.S. in 2019. Last year, the FDA expanded its use to cover use in people 12 months and older, versus its previous approval only in adults. More than 300,000 people received the vaccine during the 2018 DRC outbreak via the ring vaccination approach, including pregnant women and infants. That outbreak had a fatality rate of 66%, with 2,287 reported Ebola-related deaths. The largest Ebola outbreak in history took place in West Africa a few years prior, killing more than 11,300 people.Elsewhere on the Ebola countermeasures front, Regeneron markets a triple-combo antibody treatment for the virus, while Johnson & Johnson and Bavarian Nordic also have a WHO-prequalified vaccine regimen. Merck, for its part, was the first to score approval for an Ebola vaccine. The company took over the shot from original developer National Microbiology Laboratory and licensee NewLink Genetics during the West African outbreak in 2013.