WHO Backs Use of Experimental Ebola Drugs as Death Toll Tops 1,000
ZMapp is on its way to Liberia
A panel of medical ethics experts at the World Health Organization (WHO) has ruled that it is ethical to offer unproven drugs or vaccines to people infected or at risk in West Africa’s deadly Ebola outbreak, but cautioned that supplies will be limited.
During the past decade, research efforts have been invested in developing drugs and vaccines for Ebola virus disease (EVD). Some of these potential treatments have shown promising results in the laboratory, but they have not been evaluated for safety and efficacy in human subjects. The large number of people affected by the 2014 West Africa outbreak, and the high case–fatality rate, have prompted calls to use investigational medical interventions to try to save the lives of patients and to curb the epidemic.
Therefore, WHO convened a consultation to consider and assess the ethical implications for clinical decision-making regarding the potential use of unregistered interventions. The agency issued its conclusions on August 12.
In the particular circumstances of this outbreak, and provided certain conditions are met, a panel of experts reached consensus that it is ethical to offer unproven interventions with as yet unknown efficacy and adverse effects as potential treatment or prevention for EVD.
The panel also unanimously agreed that there is a moral duty to evaluate these interventions in clinical trials to definitively prove their safety and efficacy or to provide evidence to stop their utilization.
The West Africa Ebola virus epidemic — the world's largest and most deadly so far — has killed at least 1,013 of the more than 1,848 people it has infected in Guinea, Liberia, Sierra Leone, and Nigeria. WHO has characterized the epidemic as an international health emergency.
A Spanish priest who became infected while helping patients in Liberia died August 12 in a Madrid hospital just 5 days after being evacuated.
Liberia has requested samples of the experimental drug ZMapp (Mapp Biopharmaceutical), which showed positive effects in two U.S. health workers but failed to save the Spanish priest. Supplies will be brought in from the U.S. later this week, the Liberian government said.
ZMapp is composed of three humanized monoclonal antibodies manufactured in plants, specifically Nicotiana. It is an optimized “cocktail” combining components of MB-003 (Mapp) and ZMab (Defyrus/PHAC).
ZMapp was first identified as a drug candidate in January 2014 and has not been evaluated for safety in human subjects.