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As they race to test an experimental coronavirus vaccine, researchers aren’t waiting to see how well it prevents infection in animals before trying it in people, breaking from the usual protocol.

“I don’t think proving this in an animal model is on the critical path to getting this to a clinical trial,” said Tal Zaks, chief medical officer at Moderna, a Cambridge, Mass.-based biotech that has produced a Covid-19 vaccine candidate at record speed. He told STAT that scientists at the National Institutes of Health are “working on nonclinical research in parallel.” Meanwhile, the clinical trial started recruiting healthy participants in the first week of March.

That isn’t how vaccine testing normally happens. Regulators require that a manufacturer show a product is safe before it goes into people, and while it isn’t enshrined in law, researchers almost always check that a new concoction is effective in lab animals before putting human volunteers at potential risk.


“This is very unusual,” explained Akiko Iwasaki, a Yale University microbiologist who studies the immune response to viruses. “It reflects the urgency to develop vaccines to counter the Covid-19 pandemic.”

To some, the sweep of outbreak is emergency enough to justify simultaneously working on steps that would normally be done sequentially. To others, jumbling the order of the recipe seems morally questionable, because there could potentially be unknown hazards and it’s unclear how effective this particular formulation is.


“The traditional vaccine timeline is 15 to 20 years. That would not be acceptable here,” said Mark Feinberg, president and CEO of the International AIDS Vaccine Initiative, whose work as chief public health and science officer at Merck Vaccines was instrumental in the development of the immunization against Ebola. “When you hear predictions about it taking at best a year or a year and a half to have a vaccine available … there’s no way to come close to those timelines unless we take new approaches.”

He knows that it’s important to see how well a new vaccine can stop infection in animals, but to him, given the current emergency, it makes sense to start human safety testing before those studies are finished. “I personally think that’s not only appropriate; I think that’s the only option we have,” Feinberg went on.

Yet ethicists aren’t so sure that the eventual benefits of rushing this unproven vaccine into clinical trials will outweigh the risks. “Outbreaks and national emergencies often create pressure to suspend rights, standards and/or normal rules of ethical conduct. Often our decision to do so seems unwise in retrospect,” wrote Jonathan Kimmelman, director of McGill University’s biomedical ethics unit, in an email to STAT.

The question is complicated by the newness of the science at play. The technology that has allowed Moderna to craft an experimental vaccine so fast has not yielded a single immunization that’s made it to market so far. It’s a trendy idea: Instead of injecting people with a weakened pathogen or proteins from the surface of a pathogen, so that our bodies will learn to fight off such infections in the future, scientists are betting on a kind of genetic hack, a lab-made concoction that gets the body to produce its own virus-like bits which it will then train itself to combat.

At the center of it all is a molecule called messenger RNA, or mRNA. Inside of us, its normal function is to transmit the instructions contained within our DNA to the cellular protein-making factories that carry them out. In Moderna’s recipe, the mRNA is synthetic, programmed with the goal of getting our inner machinery to produce certain coronavirus-like proteins — the very proteins that the pathogen uses to gain entry into our cells. Once those homemade dummy virus particles are there, the thinking goes, our bodies will learn to recognize and clobber the real thing.

The method’s greatest advantage is its speed. The virus behind the outbreak that began in Wuhan, China, was identified on Jan. 7. Less than a week later — on Jan. 13 — researchers at Moderna and the NIH had a proposed sequence for an mRNA vaccine against it, and, as the company wrote in government documents, “we mobilized toward clinical manufacture.” By Feb. 24, the team was shipping vials from a plant in Norwood, Mass., to the National Institute of Allergy and Infectious Diseases, in Bethesda, Md., for a planned clinical trial to test its safety.

Though sponsored by NIAID, the first-in-human experiment is taking place in Seattle, at the Kaiser Permanente Washington Health Research Institute. Researchers began recruiting healthy volunteers in early March. Their plan is to enroll 45 people between 18 and 55, who will get two shots of Moderna’s investigational vaccine, about a month apart. For their trouble, participants will get $100 for each in-person study visit, for a total of $1,100.

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That doesn’t mean the scientists have sped past animal testing entirely. Virologists at NIAID tried the new vaccine on run-of-the-mill lab mice, the institute told STAT by email, on the same day that the trial began enrolling participants. Barney Graham, director of NIAID’s vaccine research center, later added that those mice showed the same sort of immune response generated by a similar mRNA vaccine against MERS, another coronavirus. “That level of immune response was sufficient to protect mice from MERS CoV infection,” Graham wrote.

The trouble is, your average lab mouse doesn’t seem susceptible to the new virus. While the bug behind Covid-19 has no trouble co-opting molecules on human cells to get inside and start multiplying, it isn’t so good at latching onto the mouse equivalent. Although Graham can say the response produced in everyday mice looks similar to one that helped mice combat the virus in their bodies when infected with MERS, he can’t yet say the same thing for the new coronavirus, because the mice susceptible to this pathogen aren’t ready yet.

These pathogen-susceptible rodents were specially engineered in the wake of another coronavirus outbreak: SARS, in the early 2000s. To make them easier to infect, scientists adorned their cells with the human molecule that allows certain coronaviruses to slip inside. But when coronavirus research slowed between outbreaks, scientists couldn’t justify the expense of keeping many of them; so while these mice seem to be susceptible to the new virus, too, there aren’t currently enough for experiments to start.

“Those mice in the U.S. are being bred so that the colony can be enlarged,” explained Graham, adding, that they “will be available for experiments within the next few weeks.”

The researchers have not said outright that they’ll start dosing humans before they have results showing how well the vaccine works in virus-susceptible animals, but when asked whether they would, Graham replied, “Safety and product integrity are the primary criteria for starting a Phase 1 trial and mRNA has now been used in several clinical trials and shown to be safe and well tolerated.”

Kaiser Permanente did not reply to STAT’s request for the informed consent form that trial participants are signing, which is supposed to describe the risks they will face, and like Moderna, referred all questions about preclinical testing for this vaccine to NIAID.

To Holly Fernandez Lynch, assistant professor of medical ethics at the University of Pennsylvania, starting human experiments before finishing all of the usual animal testing first raises a serious question. “We may not be able to minimize the risks as much as we would hope to, because we have the time pressure of the outbreak,” she said. “Are the remaining risks acceptable in relation to the benefits of the research?”

The potential benefits are to have a vaccine against Covid-19 ready for general use as soon as possible. That won’t happen for a year at least. That timeline, Lynch went on, is “insanely fast,” but it probably won’t be fast enough to help slow the current outbreak.

If this research meant a vaccine might be ready by this June, she said, people would probably be all for it in spite of the cut corners. “If we’re talking about us getting a vaccine in June of 2021 rather than March of 2021, that’s a much more uncertain scenario,” she said. “We shouldn’t delude ourselves into thinking that skipping over steps is going to get a vaccine into our hands by next week or next month.”

Even if researchers decide it’s worth forging ahead and testing a new vaccine’s safety in people while still figuring out whether it works to prevent infections in susceptible animals, they need to be ready to stop the human trial if the results don’t look good in mice, said Karen Maschke, a scholar at the Hastings Center, a nonpartisan think tank in Garrison, N.Y., and the editor of the journal Ethics & Human Research — whether that’s because there are bad side effects or simply because the immunization doesn’t work.

“There’s no reason to put people at risk in a study if there’s no efficacy,” she said, “even if it’s just the burden of being in a study. You don’t burden people to be in a study if the intervention is not going to help.”

Then again, she pointed out, animal studies are often lousy predictors of what will be effective in people.

Moderna itself acknowledges that the task is daunting, and this effort might not succeed. “We have not previously tested our rapid response capability and may be unable to produce a vaccine that successfully treats the virus in a timely manner, if at all,” the company wrote in a document filed with the Securities and Exchange Commission.

What the company doesn’t say is that it has not yet brought a single product to market, even in non-emergency times. The majority of candidate vaccines fail. If against all odds, this rushed project does work out, then the company needs to be extra careful about monitoring what happens to those people who get it, said Arthur Caplan, head of medical ethics at New York University’s Grossman School of Medicine. “The more you speed it up … the greater the obligation you have to track what’s going on when you get it out into the real world.”

He doesn’t see it as inherently unethical for animal efficacy studies and human safety studies to happen at the same time, though he said vaccine skeptics might use this as fodder.

To vaccine-makers, though, Covid-19 may well simply be a test case for other outbreaks to come. As Feinberg, of the International AIDS Vaccine Initiative put it, “This is a world where we’re going to see infectious diseases we’ve never seen before, and we need to get really good at developing vaccines against them quickly.”

Damian Garde contributed reporting. 

  • Seriously? There are so many ethical pushasides here I am wondering what country I woke up in?
    We don’t see an ethical problem with paying someone a maximum of $1100 to put themselves at risk?
    This new approach of cast all concerns to the wind sounds like something out of a Marvel comic book.

    “In Moderna’s recipe, the mRNA is synthetic, programmed with the goal of getting our inner machinery to produce certain coronavirus-like proteins — the very proteins that the pathogen uses to gain entry into our cells. Once those homemade dummy virus particles are there, the thinking goes, our bodies will learn to recognize and clobber the real thing.“

    Injecting “healthy” individuals with something that is directly supposed to engage with human foundational expression of being. Here’s a question would you try it on your husband or your wife and your children?
    “ He doesn’t see it as inherently unethical for animal efficacy studies and human safety studies to happen at the same time, though he said vaccine skeptics might use this as fodder.”
    Let’s be honest – there is a race for billions of dollars to be made here
    with plenty of side bar payouts to smooth the path.

  • Latest research indicates coronavirus is a GI pathogen (avoid bat soup), heads for the colon, with diarrhea a frequent, under-reported, sentinel symptom. This occurs before the CDC/WHO’s watch-for “dry cough, fever and dyspnea”. Feces tests positive before the virus is detected in the upper airway.

    So if an asymptomatic patient uses a toilet – home, workplace, airport terminal, hospital waiting room – it becomes contaminated with coronavirus: aerosolization from flushing and lax hand washing. (Only 31% of men wash their hands after using thetoilet ! – NYTimes 3/5/20). Anyone using those toilets or cleaning them afterward is then exposed to the virus. A suspected, self-quarantined patient can spread the virus to family members, unless each has their own bathroom.

    In nursing homes, an infected Alzheimer patient’s micro-fecal vectors can be numerous. Soiled adult diapers, contaminated bed linen, staff/visitors tracking contaminants on their shoes et al. Are these old people really spewing respiratory droplets on each other from their beds or wheelchairs ? If not, how is the virus infecting more residents and staff?

    Tracking fecal contamination may be an impossible task. What toilets were used by asymptomatic patients, who did their laundry, who shook hands with them (after they hurried out of a rest room, hands unwashed ?) The CDC and WHO “guesstimate” how long the virus survives on surfaces -a big unknown. Obsessing over oral swabs is not slowing this pandemic and staying six feet away from each other is not a solution.

    • I wish to be part of this clinical trial.

      From my knowledge of this COVID-19, I suppose it doesn’t survive in temperature above 30 degree celcius.
      In my humble opinion, may I suggest that every environment is conditioned to rise about that temperature.

      In Nigeria, where I stay, since the first two confirmed cases in February 24, no death was recorded, neither another further confirmed case. Why? Because our normal environmental temperature doesn’t support the spread.

      My current city, Minna, just 200Km from Abuja is recording 39degrees celcius.

      I am only suggesting that if the temperature of every environment could be conditioned as such, it might help.
      Anyone with another view can correct me, but my interest in this clinical trial is very much alive.

  • Are we using natural resources to find a vaccine such as from Whales and dolphins? I am not suggesting testing on them, just take samples of blood from them and introduce covid-19 to their blood to look at the results?

  • I don’t understand why there cannot be a personal choice of whether we get it or not. I am a physician and my under graduate degree was in microbiology. I have a better idea for testing. Get 1,000 physician volunteers (should be well informed, I will be glad to be first) and give us what potential vaccine we have and see what happens. Vaccine in 3 months. I really find it repugnant and unfair that some ethicist tells me where I should take my chances. Actions like that are also immoral.

    • The other point they appear to miss is that this caution in the face of a full blown pandemic is guaranteed to consign tens upon tens of thousands (at least) of the elderly and those with co-morbidities to an early death.

      Nobody seems to be asking them whether they would take the chance of an adverse reaction to potentially avoid a fairly high % chance of death from this disease.

    • OC, they are moving as fast as possible to have effective treatments for people in these groups as well. They can thank whatever they hold sacred that they live in a nation without socialized medicine, where brutal triage leaves such people without much hope. The stories coming from Italy and China as to the fate of those in this triage basket are difficult to ponder.

      In the meantime there is rapid progress here on plasma therapy that may be available in a few weeks. This is difficult to scale up on a short timeline but we’ve got some competent people working on that, who are sure to exceed anything done on this in the past, so … take heart.

  • Frankly those “ethical concerns” seem a bit quaint in the face of catastrophic and preventable excess deaths in the at risk populations. E.g. In large swathes of Italy where Octagenerians (and many younger patients) with potentially many, many years of life left are being left completely untreated due to lack of resources:

    Those people who will be tested are volunteers. As long as the risks are adequately explained the scale of this calamity (particularly with many, many survivable cases perishing due to healthcare system constraints) supports taking a more aggressive course of action.

    Similarly Doctors should be re-assessing the relative risks of drugs that could potentially shorten recovery time and free up hospital beds, particularly where drugs are well understood. E.g. While statistical invivo evidence is sparse Chinese and Korean physicians recommend treatment with chloroquine or hydroxychloroquine based on anecdotal evidence. In vitro evidence for efficacy is strong and the risks of these drugs are fairly well understood and modest after 70 years of use (particularly Hydroxychloroquine).

    If widespread treatment can free up beds faster for new critical cases with minimal likely extra risk vs purely supportive care shouldn’t this be taken into account? Frankly the much higher mortality rates (even amongst age groups) being reported out of Italy vs Korea and China (ex Hubei) suggest more aggressive treatment regimes may be well worthwhile.

    • The very limited use of convalescent plasma is also somewhat inexplicable to me (the Chinese appear to have deployed it to some extent). This is a tried and tested approach (in previous pandemics) with relatively low risks if appropriate screening of blood product is done correctly.

      With almost 75k recovered patients globally a co-ordinated approach to gathering blood, screening and processing it could generate enough plasma to treat substantial numbers of serious cases in at risk populations while the disease is early enough in its course to affect the outcome.

    • I agree with you on the POSSIBLE use of Hydroychloquine. There is a very recent article published I believe 3-4 days earlier entitled The Use of Antimalarial Drugs against Viral Infection The lead author is Sarah D’Alessandro
      Sorry cut and paste to the article itself doesnt seem to work for me but it is comprehensive and discusses a number of anti malarial drugs.

      You may also be interested in the articles referenced at footnotes 145-147.

      I am not a physician so take my advice with a grain of salt but I believe these are best theorized as preventing a cytokine storm caused by an overresponding immune system. I could see this as being counterproductive right away for the vast majority of patients when their immune systems are actually performing and destroying the virus as needed with minimal, if any damage to the rest of the body. So I would think in theory that these would only be used in patients with acute respiratory distress especially where an overactive immune system is damaging other organs with a cytokine storm.

      Interesting though that OTHER compounds used in fighting malaria might also have positive effects in reducing the side infections, like bacterial pneumonia, or even in apparently reducing total viral loads…however the state of testing is very very low, either stuck in in vitro analysis or in in vivo murine models…but some of these are very well known as to their side effect profile . Best advice have a well qualified physician that you know will be willing to use some approved meds “off label” should your condition, when ill, warrant it

  • Ampligen might be a solution for Coronavirus.

    Ampligen has been tested in animals for SARs and humans!

    From the CEO . . .
    “As we have been saying all along, this emerging pandemic is caused by a virus that has nearly identical regulatory RNA sequences to the original SARS coronavirus, known as SARS-CoV-1, in respect to pathogenesis. This means that the prior studies of Ampligen in SARS-CoV-1 animal experimentation may predict similar protective effects against the new virus. The WHO has recently renamed this emerging, highly pathogenic virus as SARS-CoV-2,” said AIM CEO Thomas K. Equels. “Ampligen had excellent antiviral activity against the earlier SARS coronavirus in U.S. National Institutes of Health-contracted animal experiments. In those studies of SARS-infected mice, Ampligen stands out as the only drug tested that conferred a significant survival effect: 100% of the Ampligen-treated mice survived, while none of the untreated mice survived. Because SARS-CoV-2 shares many critical similarities with SARS-CoV-1, Ampligen may have an important role to play in developing a protective early-onset therapy for this new highly pathogenic coronavirus in humans, where currently there is no known effective therapy. We are proud to work with Japan’s universally esteemed NIID in the battle to curb this emerging potential pandemic.”

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