Kent Brantly and Nancy Writebol, the American ebola patients now being treated in the isolation unit at Emory University Hospital, received an experimental treatment while still in Liberia that may have saved their lives. James Hamblin looks into just what this “top-secret serum” is:
[It’s] a monoclonal antibody. Administration of monoclonal antibodies is an increasingly common but time-tested approach to eradicating interlopers in the human body. In a basic monoclonal antibody paradigm, scientists infect an animal (in this case mice) with a disease, the mice mount an immune response (antibodies to fight the disease), and then the scientists harvest those antibodies and give them to infected humans. It’s an especially promising area in cancer treatment.
In this case, the proprietary blend of three monoclonal antibodies known as zMapp had never been tested in humans. It had previously been tested in eight monkeys with Ebola who survived—though all received treatment within 48 hours of being infected. A monkey treated outside of that exposure window did not survive. That means very little is known about the safety and effectiveness of this treatment—so little that outside of extreme circumstances like this, it would not be legal to use. [Sanjay] Gupta speculates that the FDA may have allowed it under the compassionate use exemption.
John Timmer has more on the treatment:
Fortunately, Mapp [Biopharmaceutical, the drug company working on zMapp,] has been publishing papers describing its progress on an Ebola treatment as it went along, so it’s possible to understand how the therapy was developed and how it operates.
Despite its fearsome behavior, Ebola is a fairly simple virus, with only seven genes. The gene that is essential for the virus to attach to human cells, called Ebola glycoprotein, has been identified previously. Antibodies that stick to this protein would be expected to block infection of new cells and target any virus circulating in the blood stream for destruction. The problem appears to be that an effective antibody response comes too late for the patients. (The virus also takes steps to tone down the immune response.) Mapp decided to do the immune system’s job for it by making antibodies that can then be injected into infected individuals to perform the same function. The challenges are making the right ones and making enough of them.
Shirley Li notes that zMapp isn’t the only experimental ebola treatment out there:
So why ZMapp, of all the experimental solutions to Ebola, of which there are many? Perhaps it comes down to Mapp’s recent successes: The NIH included Mapp in its $28 million five-year grant awarded to five companies to research Ebola further in March. A press release dated July 15, 2014 revealed that Defyrus, a private life sciences biodefense company based in Canada, had partnered with Mapp’s San Diego-based commercialization partner firm Leaf Biopharmaceutical Inc., to push the ZMapp serum’s clinical development. And just last week, the Defense Threat Reduction Agency announced it awarded a contract to Mapp to continue development of the serum.
Still, fighting Ebola means a multi-pronged attack. While Mapp’s method focuses on eradicating the disease after infection, the NIH has been working on preventing it in the first place. In the NIH’s case, it’s working to promote development of antibodies within the subject, instead of injecting them from an outside source that survived Ebola.
Steven Hoffman and Julia Belluz blame the lack of an effective ebola treatment until now on the way pharmaceutical companies prioritize their R&D:
Ebola will continue to move through Africa — this time, and again in the future — not only because of the viral reservoirs and broken health systems specific to the continent. There are much larger issues at play here. Namely, the global institutions we designed to promote health innovation, trade, and investment perpetuate its spread and prevent its resolution.
This shouldn’t be news. Most all of the money for research and development in health comes from the private sector. They naturally have a singular focus — making money — and they do that by selling patent-protected products to many people who can and are willing to pay very high monopoly prices. Not by developing medicines and vaccines for the world’s poorest people, like those suffering with Ebola. Right now, more money goes into fighting baldness and erectile dysfunction than hemorrhagic fevers like dengue or Ebola.
Follow all of our ebola coverage here. Update from a reader:
In the past I have been very critical of your coverage and thoughts on scientific matters; it’s incredibly frustrating to see published opinions littered with “rookie mistakes” from people who lack scientific training. As someone who is highly educated in these matters and has to compete for diminishing public funds, I have no tolerance for the long history of scientific inaccuracy from the media.
Having said that, your coverage of the Ebola epidemic has been pleasantly accurate and appropriate. I especially appreciate you highlighting Steven Hoffman and Julia Belluz’s article. They highlight a searing problem in our current research system; research priorities go towards profitable markets. The federal government is supposed to offset that, but thanks to the current batch of Republicans, worthwhile funding opportunities are going unfunded.
A colleague of my boss recently received a perfect score on a federal grant, but it did not get funded. There was nothing wrong with the grant scientifically, conceptually, or practically; they just ran out of money. The big problem is that funding opportunities aren’t growing while the scientific community is expanding. This has led us to the current ultra-competitive environment where there is no lack of sound ideas, projects, and causes that can directly be addressed and make real, lasting impacts on people’s lives.
But there’s no profit there, so Big Pharma researches ED, makes boner pills instead, and sleeps on beds of cash while poor people die of Ebola. “And the beat goes on…”