53 drugs that may block Ebola identified

New York: Researchers have found 53 existing drugs that may keep the deadly Ebola virus from entering human cells, a key step in the process of infection.

The study led by researchers at the Icahn School of Medicine at Mount Sinai and the National Institutes of Health (NIH) in the US, found that among the better known drug types shown to hinder infection by an Ebola virus model are several cancer drugs, antihistamines and antibiotics.

Among the most effective at keeping the virus out of human cells were microtubule inhibitors used to treat cancer.

"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," said lead author Adolfo Garcia-Sastre, Director of the Global Health and Emerging Pathogens Institute within the Icahn School of Medicine at Mount Sinai.

"Many of the compounds identified in this study promise to become lead compounds in near-future drug development efforts studies targeting this virus," said Garcia-Sastre.

There is no approved treatment for Ebola virus infection, and the estimated mortality rate of the current Ebola outbreak is nearly 70 per cent in many areas.

Antibody-based therapy has proven effective in animal studies, and has been used for the treatment of a few patients, but has not been confirmed in clinical trials.

Ebola vaccine trials are getting underway as well, but vaccines will not be available for some time.

The research team used a miniaturised, high-speed technology to screen through sample libraries of 2,816 compounds already approved by the US Food and Drug Administration for other uses.

Their assay was designed to identify compounds that blocked the ability of the Ebola virus to enter and infect human cells by at least 50 per cent.

While fully intact Ebola virus is a biosafety level (BSL) 4 pathogen and dangerous to work with, the team created a virus-like particle comprised of the Ebola proteins (glycoproteins and matrix proteins) that enable the virus to enter cells, but without many of the genes and proteins that make the virus deadly.

When they inserted a fluorescent reporter protein in this virus-like shell, their test became capable of high-speed screening to see which drugs blocked the entry of Ebola-like viral particles into cells as measured by fluorescence.

The team's screen yielded 53 drugs that block Ebola virus-like particles from entering human cells.

The study was published in the Nature Press journal Emerging Microbes and Infections.