This summer, ZMapp made headlines when it was reported that the antibody cocktail was part of the treatment regimen included in helping two patients at Emory University Hospital recover from their Ebola infections.
Details of those two patients’ medical ordeal are now available in the New England Journal Of Medicine
. Lyon et al report on the success they had in treating the two patients with Ebola infection who were brought from Liberia to Emory University Hospital in Atlanta GA. The first patient (Kent Brantly
), was a 33-year old doctor working with Ebola patients in Liberia who was diagnosed with Ebola virus disease in Liberal brought to the Emory Clinic on day 10 of the infection. The second patient (Nancy Writebol
) was a 59-year old missionary working in the same facility. She was transferred to Emory on day 14 of her infection.
The course of treatment for both patients included ZMapp while they were in Liberia (on day 9 for patient 1 and on day 10 for patient 2). According to the authors, both patients also received aggressive fluid and electrolyte replacement as part of their treatment as well as other therapies. Whether or not ZMapp led to their recovery is unknown. At present, clinical trials still need to be performed to determine the safety and efficacy of ZMapp in Ebola infected patients. The antibody cocktail has only been tested properly in animal models. In their discussion, the authors wrote:
"The clinical benefit of the experimental monoclonal antibody therapy in these patients is unknown. 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. Studies in animals have shown a survival benefit for ZMapp even when treatment was initiated after the onset of symptoms. However, there are currently no data on the safety or efficacy of ZMapp in humans. Clinical improvement in these patients could have resulted from a direct effect of the antibodies, from improvement in fluid status through increased oncotic pressure, or from other unidentified factors. Controlled clinical trials are needed to assess the efficacy of ZMapp for EVD (Ebola virus disease)."
The authors of the report concluded:
“Our limited experience with two patients cannot be extrapolated to all patients with EVD. However, intensive care nursing, aggressive oral and intravenous rehydration, electrolyte supplementation, and transfusion of blood products appeared to be critical for a positive outcome in our patients with EVD. “
ZMApp is an antibody cocktail being developed by Mapp Biopharmaceutical. Last month the company stated they had run out of its limited supply of ZMapp in August but they are working with the U.S. government
to find a means to manufacture the cocktail.
Lyon GM, Mehta AK, Varkey JB, et al. Clinical Care of Two Patients with Ebola Virus Disease in the United States. New Engl J Med 2014 [Epub ahead of print] DOI: 10.1056/NEJMoa1409838