Blood from man who survived Ebola Virus may be used to develop new treatment

He is known as “Subject 1,” and 20 years ago he survived an Ebola outbreak in Kikwit, Democratic Republic of the Congo. He battled the disease for weeks before recovering and returning to the Ebola wards to care for others with the virus. As reported in Scientific American, the blood from Subject 1 may offer new possibilities for developing treatments for Ebola, as he has produced some of the strongest antibodies against the disease found so far.

Nancy Sullivan is a viral immunologist for the U.S. National Institute of Allergy and Infectious Diseases in Bethesda, Md, who led the research that identified the antibody. “It’s really stunning that a single antibody can protect against Ebola,” she said.

Two papers, published Feb. 26 in the journal Science, described the antibodies, one of which, called mAb114, has proven capable in saving six Ebola-infected monkeys. Some of those monkeys recovered even though they were not treated until five days after becoming infected. An antibody cocktail known as ZMapp is the only other possible Ebola treatment that has proven as effective in animal studies.

On Feb. 23, researchers reported clinical trial results testing ZMapp. Out of 36 people who were given ZMapp, only 78 percent survived, compared with 63 percent of patients who were not given the drug, a result that is not statistically significant.

The new Ebola antibody offers hope for an alternative to ZMapp, which has many drawbacks. Patients receiving ZMapp must receive large amounts of the drug, which can cause side effects that include rashes and welts, fevers, low blood pressure and rapid heart rate. One of the studies reported last week tested the mAb114 antibody at doses similar to those used with ZMapp, but Sullivan says the plan is to further test to determine whether lower doses are effective.

The mAb114 antibody works by binding to the Ebola virus, following it into the cells, and then blocking it from reproducing. Ebola typically hides the protein that it uses to bind to receptor proteins inside cells, allowing the virus to reproduce. This prevents antibodies that bind to Ebola outside the cells from stopping it from reproducing.

The next step is for Sullivan and her team to continue testing to determine whether mAb114 is safe for use in humans. Researchers hope to have several possible drugs to use in fighting Ebola virus disease in case some are easier to make or work better. “It’s sensible to not put all your eggs in one basket,” she says.