TRENTON, N.J. (AP) — The U.S. and Liberian governments have just begun the first formal patient testing of an experimental Ebola virus treatment that's only been used on an emergency basis.
The drug, ZMapp, contains three genetically engineered proteins designed to hone in on a target on the surface of the deadly virus to stop the disease's progression. ZMapp, developed by San Diego-based Mapp Pharmaceuticals Inc., is "grown" in tobacco plants engineered to make large quantities of the virus-blocking proteins.
Adults, as well as children of any age, will be enrolled in the study if they are admitted to Ebola treatment units in Liberia or are health care workers returning to the U.S. for treatment after being infected while serving in West Africa. That's happened to seven U.S. medical and aid workers.
In addition, adults and children who may have acquired Ebola in the United States from contact with an infected person will be enrolled. That has happened to only two people — the nurses who treated patient Thomas Eric Duncan, who had traveled from Africa and died at a Dallas hospital.
"We don't expect that they'll be a significant contribution (of patients) from the United States," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told The Associated Press Friday.
In addition, the epidemic is waning in Liberia, so Fauci's agency is negotiating with officials in Sierra Leone, which currently has far more Ebola cases, to add that country to the study.
The current outbreak is the worst of the 24 since 1976. So far, the virus has infected nearly 24,000 people and killed more than 9,600, according to the World Health Organization's most recent statistics. In the week through Feb. 22, only 99 new cases were reported in Guinea, Sierra Leone and Liberia.
The goal is to enroll 200 patients and to finish the study in December 2016, which will be difficult if the epidemic continues to wane.
"There is certainly a possibility that we may not get enough patients to finish" the study, Fauci said, adding, "You can be certain that sooner or later, we will see another outbreak in one or more of the African countries."
His institute said half the study participants will receive three ZMapp injections over three days, plus supportive treatment. The other half, the control group, will only receive the current standard of care: supportive treatment consisting of intravenous fluids, medication for any other infections they get and therapy to maintain blood pressure and sufficient oxygen intake.
Each participant will be monitored for up to a month after hospital discharge. Researchers will compare how well the two groups fare.
The institute plans to then conduct similar studies of five additional experimental Ebola treatments. Meanwhile, at least three potential vaccines against Ebola also are in testing.
ZMapp has previously been given under emergency authorization to a total of nine infected patients in the United States, Western Europe and Africa. Nearly all recovered. In testing in monkeys, the drug proved potent against the virus and saved animals from death as much as five days after they were infected with the Zaire Ebola strain, the one causing the West Africa outbreak.
Meanwhile, President Obama met Friday in the Oval Office with Liberian President Ellen Johnson Sirleaf. Obama told reporters in advance that they were to discuss their efforts to fight Ebola, how to prevent complacency as case numbers fall and ways to help rebuild the economy and infrastructure in Liberia, which have been hurt by the epidemic.
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