An experimental drug given to one of the US citizens infected with the Ebola virus gives new hope to travelers to Africa. CNN and British media are reporting that this life-saving drug has only been tested on primates. In dire circumstances it can be given to individual people under a compassionate use rule of the FDA.
Vials of the drug called 'zMapp' were reportedly flown to West Africa and given to Dr Kent Brantly and Nancy Writebol, who were infected after treating patients. Their conditions improved soon after, and they were flown back to the US for further treatment.
"Within an hour of receiving the medication, Brantly's condition was nearly reversed", says CNN's chief medical correspondent, Dr Sanjay Gupta. He said one of the doctors described the turnaround as "miraculous", which is "not a term we scientists like to throw around".
Developed by an American biopharmaceutical company, zMapp consists of antibodies from an infected animal's blood. This type of drug is used in the treatment of some forms of cancer. However, according to early clinical trials, the treatment is only effective within a limited time frame after infection, with optimum results reported when administered within 24-hours.
The American healthcare workers are among the first humans to take the medication under an investigational use. They likely were informed of the risks and agreed to them. This allows use of an investigational drug outside of a clinical trial to treat a patient with a serious or immediately life-threatening disease or condition who has no comparable or satisfactory alternative treatment options.
Scientists explain results of tests on non-human primates (NHPs):
Ebola virus is one of the most aggressive infectious agents and is capable of causing death in humans within days of exposure. Recent strategies have succeeded in preventing infection in NHPs after treatment; however, these strategies are only successful when administered before or minutes after infection. Research shows that a combination of three neutralizing monoclonal antibodies directed against Ebola resulted in complete survival (four of four macaques) with no apparent side effects when three doses were administered 3 days apart beginning at 24 hours after a potential lethal exposure. The survivor NHPs demonstrated an immune response.