The screening process was designed to identify compounds able to block Ebola from entering and infecting human cells by at least 50%.
The estimated mortality rate of the current Ebola outbreak is nearly 70% in many areas. There is no approved treatment for the infection, though trials for an Ebola vaccine are underway.
Recently, Medical News Today reported on the results of a small trial in humans of an experimental Ebola vaccine. The study found that the vaccine produces an immune response and is safe and well-tolerated. The researchers suggested that the vaccine's development may be fast-tracked due to the study's results.
Antibody-based therapy has also been effective in animal studies, but its success in human patients has not yet been confirmed in clinical trials.
The team behind the new study used "miniaturized, high-speed technology" to screen samples of 2,816 existing compounds that have been approved by the Food and Drug Administration (FDA) for other uses. The screening process was designed to identify compounds able to block Ebola from entering and infecting human cells by at least 50%.
By inserting a fluorescent protein into the virus, the team was able to enhance the speed of the screening, as the penetration of the virus into cells became more visible and easily measured.
Rather than working with the dangerous Ebola virus itself, the team created a particle comprised of Ebola proteins that mimicked the virus but lacked the genes and proteins that make Ebola deadly.
From the 2,816 compounds the researchers investigated, they found 53 drugs that block the mimicked virus from entering human cells.
"In light of the historic and devastating outbreak of Ebola virus disease, there is an urgent need to rapidly develop useful treatments against Ebola infection, and our study results argue that repurposing existing drugs may be among the fastest ways to achieve this," says lead author Adolfo García-Sastre, PhD, director of the Global Health and Emerging Pathogens Institute within the Icahn School of Medicine at Mount Sinai.
Which drugs displayed Ebola-blocking properties?
Among the 53 drugs that blocked Ebola from entering human cells were cancer drugs, antihistamines, antibiotics and selective serotonin reuptake inhibitors (SSRIs) used to treat depression. Some of these drugs also demonstrated an ability to reduce the steps of the Ebola lifecycle.
"Many of the compounds identified in this study promise to become lead compounds in near-future drug development efforts studies targeting this virus," says García-Sastre.
Next, the researchers will test the drugs in animal trials to assess what their risk for side effects is when repurposed to prevent Ebola infection. If any drugs prove to be safe and effective, then they may be deployed in outbreak areas.
Dr. Christopher P. Austin, director of the National Center for Advancing Translational Sciences (NCATS), part of the National Institutes of Health, says of the study:
"NCATS is all about getting more treatments to more patients more quickly, and this is never more urgent than in the case of a public health emergency like Ebola.
This remarkable team of scientists combined NCATS' expertise in drug screening and development with Mount Sinai's expertise in Ebola virology to rapidly identify candidate treatments for Ebola infection."