ebola treatments shows progress in sick monkeys
An experimental Ebola treatment — produced in the leaves of specially engineered tobacco plants — saved the lives of three monkeys who were already showing symptoms of the illness, said a report published in the journal Science Translational Medicine.
The report suggests that it may be possible someday to treat people who show up in medical facilities already sickened with the horrific disease.
While scientists already knew that various Ebola treatments administered before symptoms appeared were effective in animals such as monkeys, they hadn't yet shown that such treatments worked once fevers and other symptoms had set in — a key capability in real-world outbreak situations, said study co-author and virologist Gene Olinger of the Army Medical Research Institute of Infectious Diseases at Fort Detrick, Md.
"We've pushed the opportunity to treat people to the point where they walk in and say, 'I have a fever,' " he said. "A lot of folks in the field would have thought protecting an animal at the time of fever and viremia is too late to have a clinical benefit."
Working in a high-security laboratory, the team tested the drug, known as MB-003, on seven rhesus macaques that were deliberately infected with Ebola — an RNA virus that causes fevers, sore throat, diarrhea and vomiting and internal and external bleeding. The illness is often fatal.
Four of the monkeys died of Ebola, but three survived. While 43 percent success may seem underwhelming, it's a result that is statistically significant, the researchers said. And Pettitt said that it's likely that if MB-003 were being administered in the field, health workers would increase the dosage and frequency of treatment once patients fell ill, perhaps to once a day. "We think we'll get better results," he said.
The antibodies in MB-003 are manufactured in specially engineered tobacco plants, grown in a greenhouse facility in Kentucky, Olinger said. The process is quick, currently allowing production of more than a hundred doses of the drug in a seven-day cycle.
The next step for MB-003 will be for researchers to try to improve the drug's efficacy by incorporating additional antibodies.