Treating the coronavirus: improvising now, but with real hope on the horizon
Human clinical trials in China are already underway to test drugs on infected coronavirus patients
As the world holds its breath waiting to see if the novel coronavirus epidemic will develop into a global pandemic, physicians are experimenting with whatever they have available. But at the same time a new experimental drug might provide some hope for sick patients — and potentially help with future coronavirus epidemics.
According to news reports, hospitals in Bangkok, and in Hangzhou in China have been using anti-HIV drugs like Lopinavir, Ritonavir and Darunavir, in combination with anti-flu medication such as Oseltammivir or Arbidol. They claim they've had success in treating infected patients with these cocktail therapies, but in the absence of a controlled clinical trial, those claims are hard to prove.
"There is a precedent for the use of these medications to treat coronaviruses. HIV drugs were given to SARS patients. They were given to MERS patients," said Timothy Sheahan, in conversation with Quirks & Quarks host Bob McDonald.
"It's really easy to gravitate towards these things that are approved for human use, that have been deemed safe, because it could save somebody's life."
Sheahan is an assistant professor of epidemiology at the Gillings School of Global Public Health at the University of North Carolina, and has been researching coronavirus treatments since the SARS epidemic.
He holds out greater hope for a drug he's tested in cell cultures and animals, called Remdesivir.
To put it bluntly, we are shadow boxing.- Dr. Tedros Adhanom Ghebreyesus, WHO
In a recent case study published in the New England Journal of Medicine, doctors describe using Remdesivir — developed for treating Ebola — to treat a coronavirus patient in Washington State. The patient improved, with their viral load reduced, but a single case proves very little.
Sheahan said until scientists conduct rigorous human clinical trials, we can't know how these drugs will fare.
"I'm optimistic, just because I have firsthand experience with [Remdesivir] in the lab," he said.
"But none of these things have been proven effective in a randomized controlled trial."
World Health Organization director-general, Dr. Tedros Adhanom Ghebreyesu, said in a press conference on Thursday about the many unknowns in treating and preventing the spread of the novel coronavirus: "To put it bluntly, we are shadow boxing."
We found that Remdesivir could diminish replication for every coronavirus that we've tested thus far.- Timothy Sheahan, University of North Carolina
What evidence is there of potency of existing antiviral drugs?
Sheahan said based on his experience, he's sceptical about using anti-HIV drugs to treat coronaviruses.
"We've done some studies in cell culture and in mice with these HIV drugs. And they don't seem to be very potent, against MERS anyway."
In contrast, he said his tests of the drug Remdesivir on cells and mouse models of coronavirus diseases indicate it is a "very potent inhibitor of coronavirus replication."
"We found that Remdesivir could diminish replication for every coronavirus that we've tested thus far," added Sheahan.
How an effective antiviral can reduce viral spread
Remdesivir takes advantage of the coronavirus' natural life cycle by inserting a "trojan horse" that shuts down the viruses ability to make copies of itself in our cells.
When viruses infect our body, they hijack our cells building blocks and machinery to replicate themselves, making more viruses that can go on to infect other cells or people.
"What Remdesivir does is it basically tricks the virus into incorporating it rather than the building blocks that we have in our cells," said Sheahan. Viral copies with the drug decoy molecule in them are no longer viable
"Basically it can't reproduce itself and it can't be transmitted to another person or spread throughout someone's body."
Current outbreak an opportunity to test drugs in humans
Scientists in China are taking advantage of the abundance of test cases — tens of thousands of infected people — to conduct several clinical trials to get solid data on how effective existing and experimental drugs are in treating people sick with the novel coronavirus.
According to a report in the medical journal, The Lancet, scientists have already begun a clinical trial of the anti-HIV drug combination of Lopinavir and Ritonavir to determine how effective it is against the new coronavirus.
It's really easy to kind of gravitate towards [HIV drugs] that are approved for human use, that have been deemed safe, because it could save somebody's life.- Timothy Sheahan, University of North Carolina
Gilead Sciences, the company that makes Remdesivir, is also taking the opportunity to test their drug, according to an email from Sonia Choi, their VP of Public Affairs.
"We are working with Chinese authorities on two clinical trials in patients who have been infected with 2019-nCoV to determine the safety and efficacy of Remdesivir as a potential treatment for the coronavirus," wrote Choi.
Sheahan said we can be confident the HIV drugs are safe as they've already been used by millions of people.
Remdesivir has been through a limited safety trial on Ebola patients, so less is known about its potential risks.
But assuming it's safe, he said he thinks Remdesivir, especially, has great potential to treat emerging coronaviruses like 2019-nCoV. It may or may not help now, but it could be a valuable tool for the future.
"We didn't have this opportunity with SARS, really, and we haven't had this opportunity with MERS. So I think this is an opportunity for us basically to figure out ways to protect ourselves from the eventual emergence of a new coronavirus in the future."
We asked Gilead Sciences, the company that makes the drug Remdesivir, if they are ramping up production of the drug to meet demand should the drug prove to be effective against the new coronavirus. This was their response:
"We are working on mapping out our options to make access to investigational Remdesivir more widely available through appropriate channels should it demonstrate the potential to be a safe and effective treatment option based on the results of these preliminary studies.
In anticipation of potential future needs, we have accelerated manufacturing timelines to increase our available supply as rapidly as possible. We are doing this before knowing whether Remdesivir will be determined to be safe and effective to treat patients with 2019-nCoV. We are pursuing multiple strategies in parallel to increase supply. We have expanded our network of manufacturing partners to increase capacity and production, and we have begun internal manufacturing of Remdesivir to supplement the capacity of our external manufacturing network."
Written and produced by Sonya Buyting