A new report by CNN reveals that two American's were recently saved by a miracle drug called ZMapp. The down side however is that the drug before it was administered was yet to undergo human trials. Read all about it after below.
Two American missionary workers Dr. Kent Brantly's and Nancy Writebol's contracted Ebola from another health care worker at their hospital in Liberia while working with the aid organization Samaritan's Purse.
Their situation was dire. Three vials containing a highly experimental drug was flown into Liberia in a last-ditch effort to save them.
Thankfully, the drug flown in last week appears to have worked, according to a source familiar with details of the treatment.
The experimental drug, known as ZMapp, was developed by the biotech firm Mapp Biopharmaceutical Inc., which is based in San Diego. The patients were told that the treatment had never been tried before in a human being but had shown promise in small experiments with monkeys.
They were however willing to give it a try because at that point they had no other choice.
Questions about this new Ebola drug
According to company documents, four monkeys infected with Ebola survived after being given the therapy within 24 hours after infection. Two of four other monkeys that started therapy within 48 hours after infection also survived. One monkey that was not treated died within five days of exposure to the virus.
Brantly and Writebol were aware of the risk of taking a new, little-understood treatment and gave informed consent, according to two sources familiar with the care of the missionary workers. In the monkeys, the experimental serum had been given within 48 hours of infection. Brantly didn't receive it until he'd been sick for nine days.
The ZMapp vials, stored at subzero temperatures, reached the hospital in Liberia where Brantly and Writebol were being treated Thursday morning. Doctors were instructed to allow the serum to thaw naturally without any additional heat. It was expected that it would be eight to 10 hours before the medicine could be given, according to a source familiar with the process.
Brantly asked that Writebol be given the first dose because he was younger and he thought he had a better chance of fighting it, and she agreed. However, as the first vial was still thawing, Brantly's condition took a sudden turn for the worse.
Brantly began to deteriorate and developed labored breathing. He told his doctors he thought he was dying, according to a source with firsthand knowledge of the situation.
Knowing his dose was still frozen, Brantly asked if he could have Writebol's now-thawed medication. It was brought to his room and administered through an IV. Within an hour of receiving the medication, Brantly's condition dramatically improved. He began breathing easier; the rash over his trunk faded away. One of his doctors described the events as "miraculous."
By the next morning, Brantly was able to take a shower on his own before getting on a specially designed Gulfstream air ambulance jet to be evacuated to the United States.
Writebol also received a vial of the medication. Her response was not as remarkable. However, doctors on Sunday administered Writebol a second dose of the medication, which resulted in significant improvement.
She was stable enough to be evacuated back to the United States.
Are there other experimental Ebola drugs out there?
Yes. In March, the NIH awarded a five-year $28 million grant to establish a collaboration between researchers from 15 institutions who were working to fight Ebola.
"A whole menu of antibodies have been identified as potentially therapeutic, and researchers are eager to figure out which combinations are most effective and why," a news release about the grant said.
Tekmira, a Vancouver-based company that has a $140 million contract with the U.S. Department of Defense to develop an Ebola drug, began Phase 1 trials with its drug in January. But the FDA recently halted the trial, asking for more information.
At least one potential Ebola vaccine has been tested in healthy human volunteers, according to Thomas Geisbert, a leading researcher at the University of Texas Medical Branch. And last week, the NIH announced a safety trial of another Ebola vaccine will start as early as September.
How does ZMapp work?
Antibodies are proteins used by the immune system to mark and destroy foreign, or harmful, cells. A monoclonal antibody is similar, except it's engineered in a lab so it will attach to specific parts of a dangerous cell, according to the Mayo Clinic, mimicking your immune system's natural response. Monoclonal antibodies are used to treat many different types of conditions.
The medicine is a three-mouse monoclonal antibody, meaning that mice were exposed to fragments of the Ebola virus and then the antibodies generated within the mice's blood were harvested to create the medicine. It works by preventing the virus from entering and infecting new cells.
The Ebola virus causes viral hemorrhagic fever, which refers to a group of viruses that affect multiple organ systems in the body and are often accompanied by bleeding.
Early symptoms include sudden onset of fever, weakness, muscle pain, headaches and a sore throat. They later progress to vomiting, diarrhea, impaired kidney and liver function -- and sometimes internal and external bleeding.
Why did American missionary workers get the drug?
Many have asked why these two workers received the experimental drug when so many -- around 1,600 -- others in West Africa also have the virus.
Samaritan's Purse reached out to an NIH scientist who was on the ground in West Africa, according to the National Institute of Allergy and Infectious Diseases. "The scientist was able to informally answer some questions and referred them to appropriate company contacts to pursue their interest in obtaining experimental product," NIAID said.
The World Health Organization says it was not involved in the decision to treat Brantly and Writebol. Both patients had to give consent to receive the drug, knowing it had never been tested in humans before.
The process by which the medication was made available to the American patients may have fallen under the U.S. Food and Drug Administration's "compassionate use" regulation, which allows access to investigational drugs outside clinical trials.
Did doctors know it would work?
No. The drug had shown promise in primates, but even in those experiments, just eight monkeys received the treatment. In any case, the human immune system can react differently than primates', which is why drugs are required to undergo human clinical trials before being approved by government agencies for widespread use.
The two Americans' cases will be studied further to determine how the drug worked with their immune systems.
Will the drug be made available to other Ebola patients?
It's unclear. Doctors "cannot start using untested drugs in the middle of an outbreak, for various reasons," World Health Organization spokesman Gregory Hartl said.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, says scientists have to be careful about assuming this drug will work in other patients as it appears to have worked in Brantly.
"Having worked with administering antibodies for people for a really long time, that would be distinctly unusual," he told CNN. "As we all know in medicine ... you have to withhold judgment."
Does the company have more vials of the drug?
The company has very few doses ready for patient use, Fauci told CNN. "Apparently the company is trying to scale up, (but) it's not easy to scale up to very large number of doses."
Who paid for the drug and how much did it cost?
We don't know. Samaritan's Purse covered the cost of Brantly and Writebol's evacuations but did not pay for the drug, according to a spokesman.
When a patient gets an experimental drug, the drug company can donate the product under compassionate use. Mapp Biopharmaceutical Inc. might have done that in this case.
Health insurance companies typically do not pick up the tab for treatments that have not been approved by the FDA. But they would usually cover the cost of any doctor fees associated with giving the drug and any costs associated with monitoring how the drug is working.
Would this drug stop the Ebola epidemic?
If it were widely available, it certainly couldn't hurt. An effective Ebola drug could help doctors treat the deadly virus, which is killing about 60% of the people infected in West Africa. But a vaccine would be a much more effective tool in stopping this, and future, epidemics.
Vaccines are given to healthy people to prevent them from ever becoming infected. One challenge with Ebola, experts say, is that companies don't believe they could make much money from developing a vaccine, so few companies show interest.
Source: CNN
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