BY MAGGIE FOX
Doctors Without Borders says it will help test two experimental Ebola drugs and a treatment using blood from survivors at its centers at the heart of the epidemic in West Africa.
The group, known internationally as Medecins Sans Frontieres or MSF, will lend its clinics to French, Belgian and British researchers testing the drugs.
There are several experimental drugs against Ebola but most are in very short supply because they’re experimental and because there has not previously been a big market, and thus little incentive, to develop them. But governments have pushed them into the fast line since the epidemic became out of control
Ebola’s now killed more than 14,000 people and killed more than 5,000 of them, although experts say those numbers are an underestimate.
The two drugs that will be tested are a pill called brincidofovir and another drug called favipiravir. The Antwerp Institute of Tropical Medicine will test whole blood and plasma taken from survivors. No one knows if any of the therapies actually help patients; the trials will be designed to test this.
“This is an unprecedented international partnership which represents hope for patients to finally get a real treatment against a disease that today kills between 50 and 80 percent of those infected,” said MSF's Dr. Annick Antierens. “As one of the principal providers of medical care to Ebola patients in West Africa, MSF is taking part in these accelerated clinical trials to give people affected by the current outbreak a better chance of survival.”
It’s controversial and very unusual to test experimental treatments in the middle of an epidemic. Patients are likely to be desperate and may be unable to give fully informed consent. And if the treatments are not safe, they could make things worse.
But the advantage is that there are lots of patients right now, and it will be easier to compare one treatment to another with large numbers. And the World Health Organization has advised that everyone in one of these trials get the very best care available, which will mean careful monitoring and replacement of the fluids they have lost to vomiting and diarrhea — treatment that may itself help save lives.
The Food and Drug Administration has approved the experimental of brincidofovir, made by North Carolina-based Chimerix. It’s a slight alteration of the existing drug cidofovir, used to treat and to prevent an infection called cytomegalovirus. It's also being tested in people for use against serious adenovirus infections.
Favipiravir is a Japanese influenza drug that appears to help Ebola infections in mice.
U.S. Ebola patients Thomas Eric Duncan, who died last month, and Ashoka Mukpo, who has recovered, both got brincidofovir. Doctors stress that individual cases tell them little about whether a drug works. It’s necessary to test new drugs in large numbers of people.
Other experimental drugs include one made by Tekmira, a Canadian company that had begun testing it in people before some safety concerns made the FDA halt testing. ZMapp, made by California-based Mapp Biopharmaceutical, is grown in tobacco plants. It was given to Ebola survivors Dr. Kent Brantly and Nancy Writebol. Right now, the companies that make it are trying to make more.
Brantly also got a blood transfusion from another Ebola survivor, and he gave blood to be transfused into other patients.
“We want to find out whether it works for Ebola, whether it is safe and whether it can be scaled up to reduce the number of deaths in the current outbreak."
“Convalescent plasma from recovered patients, containing antibodies against pathogens, has been safely used for other infectious diseases,” said Johan van Griensven of Belgium's Institute for Tropical Medicine, who will lead the blood trial. “We want to find out whether it works for Ebola, whether it is safe and whether it can be scaled up to reduce the number of deaths in the current outbreak."
The doctors who treated Brantly and Writebol say it’s impossible to knowwhat helped them, but they say both got better soon after they received ZMapp, which uses engineered immune system proteins called monoclonal antibodies.
“The two patients were observed to have subjective and objective improvement shortly after receiving the first dose of the antibody cocktail, but this improvement occurred in the context of receiving other care as well,” they wrote in a report in the New England Journal of Medicine released Wednesday.
But the supportive care may be just as important, the team at Emory University Hopistal reported. “With aggressive fluid and electrolyte replacement, the condition of both patients improved,” they wrote.
Most Ebola patients die of multi-organ failure and septic shock, the Emory team said. But they believe fluid loss and what’s called electrolyte imbalance — the loss of minerals because of constant, unending diarrhea and vomiting — can also kill some patients.
Replacing electrolytes may save lives, they say. But it’s not a simple matter of giving someone a sports drink. For one thing, the patients may not be able to hold it down. For another, most commercial products don’t contain the right balance of electrolytes, which include magnesium, calcium and potassium, they said.
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