The wires are buzzing this afternoon with details on a freshly published study in the Journal Nature that looks at the outcome of 21 Ebola-infected Rhesus Macaques – 18 of which received the ZMapp monoclonal antibody cocktail. Incredibly, 100% of the treated monkeys – even those treated 5 days post exposure and already symptomatic – recovered.
First a link to the study, then I’ll be back with more.
Xiangguo Qiu, Gary Wong, Jonathan Audet, Alexander Bello, Lisa Fernando, Judie B. Alimonti, Hugues Fausther-Bovendo, Haiyan Wei, Jenna Aviles, Ernie Hiatt, Ashley Johnson, Josh Morton, Kelsi Swope, Ognian Bohorov, Natasha Bohorova, Charles Goodman, Do Kim, Michael H. Pauly, Jesus Velasco, James Pettitt, Gene G. Olinger, Kevin Whaley, Bianli Xu, James E. Strong, Larry Zeitlin et al.
Published online 29 August 2014
Without an approved vaccine or treatment, Ebola outbreak management has been limited to palliative care and barrier methods to prevent transmission. These approaches, however, have yet to end the 2014 outbreak of Ebola after its prolonged presence in West Africa. Here we show that a combination of monoclonal antibodies (ZMapp), optimized from two previous antibody cocktails, is able to rescue 100% of rhesus macaques when treatment is initiated up to 5 days post-challenge. High fever, viraemia and abnormalities in blood count and blood chemistry were evident in many animals before ZMapp intervention. Advanced disease, as indicated by elevated liver enzymes, mucosal haemorrhages and generalized petechia could be reversed, leading to full recovery. ELISA and neutralizing antibody assays indicate that ZMapp is cross-reactive with the Guinean variant of Ebola. ZMapp exceeds the efficacy of any other therapeutics described so far, and results warrant further development of this cocktail for clinical use.
Quite simply, a remarkable success rate by any measure. And while you can’t guarantee you’d see the same kind of results in human patients, it is highly encouraging.
That said, this news must also be tempered by fact that the existing limited supply of ZMapp has been exhausted, and it is expected that it will take weeks or even months to produce even a small quantity of the drug.
A pair of reports on this from two of the best science writers in the business. First this from Maggie Fox of NBC news.
By Maggie Fox
An experimental treatment used to treat two sick American missionaries saved a batch of monkeys infected with Ebola virus, even days after they got sick, researchers reported on Friday.
What works in monkeys doesn’t always work in humans, but it’s a piece of good news for the makers of ZMapp, a cocktail of engineered antibodies meant to boost the body’s defenses against the virus. ZMapp, made by California-based Mapp Biopharmaceutical, is grown in tobacco plants and is meant to improve on an old-fashioned approach that uses transfusions of blood from people who have survived an infection.
And this from Helen Branswell of the Canadian Press.
By Helen Branswell The Canadian Press
TORONTO – The experimental Ebola drug ZMapp was able to save infected monkeys even when treatment was only begun five days after the animals were infected, a new study shows.
This is the first research to demonstrate that an Ebola therapy could save primates if given so late in the course of their illness — a circumstance that more closely reflects how an Ebola drug would be used in people in an outbreak.
For more on ZMapp you may wish to revisit CDC FAQ On Experimental Ebola Treatments & Vaccine Development.