Experimental Drugs Aren’t The “Miracle Cures” To Ebola

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The World Health Organization (WHO) has just released updated figures on the growing epidemic in West Africa: 1,975 documented cases, 1069 of which were deaths. Up until this year, there had been 1,640 recorded deaths worldwide since the virus was first discovered in 1976. To put things in perspective, roughly two-thirds of all Ebola deaths of all-time have occurred during this particular outbreak, which started in February of this year and shows no signs of stabilizing. Doctors have only containment since ebola has no cure, though some potential treatments, such as ZMapp, are in development. While showing promising results in monkeys, ZMapp has not been tested on humans, but it has been administered under “compassionate use” to American doctors Kent Brantly and Nancy Writebol. Both show signs of improvement, which prompted questions about using experimental drugs on the frontlines of the epidemic.    

Given the nature of this particular outbreak, the World Health Organization (WHO) gave the green light on using untested medicines (but did not provide guidelines on who should receive them) in order to curb the epidemic, provided certain ethical criteria guide its provision. The question medical ethicists now face is how to distribute and administer untested medicines ethically, but this shouldn’t include treating all Ebola patients with experimental drugs such as ZMapp. While untested treatments can potentially be a useful supportive measure to containment, which was a successful measure to ending the 2012 outbreak in Uganda according to CNN, nobody can know the safety or efficacy of drugs – like ZMapp – that have not undergone clinical trials. In order to minimize the risk of a second public health disaster that may be spurred by an unknown side-effect to these drugs, ZMapp’s distribution should be limited.  

While withholding a potentially effective cure from those suffering from Ebola may seem passively cruel, it is actually more a manner of medical safety and patient protection than deliberate cruelty and bureaucratic tyranny. Whenever a new drug is in development, it heads into clinical trials in order to assess its efficacy and safety in participants. The case may be that a drug helps a patient in the present, but causes dementia five years later, or may be less effective in women than in men (it took 2 doses of ZMapp to treat Nancy Writebol but Brantly only required one), or be lethal in younger patients than older patients, and so on. Answering these questions require rigorous testing through clinical trials. Clinical trials are a pretty involved 5-phase process, but they provide researchers with important information about how safe a drug is. The trials consist of 5 phases including an increasing number of human participants in each stage. But even before heading into clinical trials, pre-clinical trials, the phase that ZMapp, dubbed “the secret serum”, is currently in, are conducted using animals in order to collect data supporting the safety of the new drug. Clinical studies are part of a strict protocol researchers working with human patients must abide by in order to protect patients, but it is a step completely absent from ZMapp, given the override granted by the FDA that allows it to be used as treatment without going through the necessary drug-approval hoops.

It is possible to gain expanded access (“compassionate use”) of an experimental 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,” according to the Food and Drug Administration (FDA). Brantly and Writebol took ZMapp under this “compassionate use” clause and have since improved, but attributing their “miraculous” recovery to ZMapp might be a bit of a stretch. About 45% of those infected in West Africa have survived without the clean water, adequate food supply, and other benefits of the developed world Brantly and Writebol grew up with. It’s possible that the Americans had stronger immune systems having grown up with proper resources. While it is tempting to point to ZMapp’s success in the American doctors as reason for further distribution, treatment in Americans isn’t quite comparable to treatment in West Africans, hence the need for clinical trials to study the drug’s effects cross-culturally to avoid potentially adverse effects Americans are not at risk for experiencing.  

ZMapp isn’t the only potential experimental cure being developed; Tekmira Pharmaceuticals Corp. is also working on developing a drug TKM-Ebola, but states in an article for ABC News that it isn’t ready to be available in Africa despite WHO’s endorsement of untested drugs. CEO Mark Murray said, “Given the severity of the situation, we are carefully evaluating options for use of our investigational drug within accepted clinical and regulatory protocols.” TKM-Ebola is actually further along the drug approval process than ZMapp, which has only been tested in monkeys. Earlier this year, Tekmira started a portion of the Phase I clinical trial in healthy volunteers, though the FDA put a clinical hold while the agency investigated how the drugs works, according to an article for the Wall Street Journal. Even though the FDA has since lifted the “clinical hold”, Murray stresses that “we’re not there yet” in terms of emergency use in patients.  

Given the massive amount of deaths due to Ebola in the current outbreak, an experimental treatment does seem better than none. But, without data gathered from clinical trials, we simply don’t know if ZMapp and other drugs will harm those it intended to save. It may make more sense to distribute experimental drugs to all of those afflicted by Ebola if the mortality rate deemed every patient virtually terminal, but that isn’t the case with this outbreak. According to BBC News, fatality rates differ from one country to another – in Guinea it’s 73%; Liberia, 55%; and Sierra Leone, 41%. The main factors are the level of preparedness and availability and quality of medical care, according to the article.

That being said, the “secret serum” isn’t necessarily the “miracle cure” to ending this epidemic, but containment might be.  In an article for the BBC, Dr. Tom Frieden, director of the Centers for Disease Control and Prevention, said that the outbreak could be stopped “by tried and true public health measures”, including tracking potential contacts those infected with Ebola may have made. He endorses the increasing of emergency management initiatives working to contain the disease, and acknowledges that there are more resources needed. The current outbreak is rapidly growing because of a lack of resources, a problem that Doctors Without Borders have earlier expressed. “With resources already stretched, health authorities and international organizations are struggling to bring the outbreak under control,” Doctors Without Borders writes on their site.

“As doctors, trying an untested drug on patients is a very difficult choice since our first priority is to do no harm,” says Doctors Without Borders. Some people are surviving the disease for some unidentified reason, according to the CDC’s webpage on Ebola, and yet-to-be-discovered side effects might harm those who had a chance of surviving. Though it may sound cold-hearted to withhold medicines until drug approval processes have been done, those safety trials are ultimately meant to protect the health of patients from a drug that may do more harm than good, especially since the survival rate for this particular outbreak of Ebola is 40% and especially since poor containment of the disease in the area is resulting in its rapid spread.

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One Comment to “Experimental Drugs Aren’t The “Miracle Cures” To Ebola”

  1. It is hard to measure exactly what allows some people to survive ebola. There are so many factors to consider. Given the circumstances, it was appropriate to give these 2 Americans the experimental drug. Although, it was a bit unpredictable as to what the outcome would have been, few things are worse than dying from ebola. To my knowledge, it is a painful disease to bear. It was also a good chance to collect some much needed data on the use of ZMapp on humans and does promote progress for experimental drugs. Of course containment should be the first option to stopping epidemic. The first step should be to halt the spread to other regions. This must be very difficult to do, since the incubation period for ebola is a little longer than other diseases. People can travel and transmit the virus without even knowing that they are infected.

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