Yesterday researchers from the Centers for Disease Control and Prevention (CDC) published encouraging findings that showed the antiviral remdesivir and antibodies in the ZMapp treatment regimen were effective in fighting the current strain of Ebola. The findings were published in The Lancet Infectious Diseases.
The study also demonstrated that a reverse-engineered virus that CDC scientists developed served as an admirable substitute for virus circulating in the Democratic Republic of the Congo (DRC), given that they did not have access to the real thing.
The two experimental treatments have been in use in the DRC since last November. Though clinical data showed their efficacy, the drugs had been developed during the 2014-2016 West Africa outbreak for use against a different strain of Ebola virus. And because Ebola is an RNA virus, it can mutate, leaving some to wonder if the treatments would be as effective against the current strain seen in the DRC.
The CDC researchers reverse-engineered a sample of the current outbreak strain—the Ituri strain—in a CDC biosafety level 4 laboratory (the highest-security type) to test the treatments. They created the synthetic virus because no samples or isolates of the current strain have been made available by the DRC.
“As technology progresses and rapid sequencing of virus strains in low-resource settings in the field becomes more and more feasible, if isolates are unavailable, we recommend a policy whereby reverse genetics is used to generate outbreak strains as a standard practice,” the authors of the study concluded.
This is the first time reverse genetics technology has been used to generate an Ebola virus isolate. In addition to showing ZMapp and remdesivir’s efficacy, the synthetic strain also validated two diagnostic tests being used currently in the DRC.