After a confusing week of mixed messaging and conflicting opinions from the public health officials advising the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC), late Thursday night CDC Director Dr. Rochelle Walensky announced her decision to recommend COVID booster vaccines for adults over 65, residents of long-term care facilities, and those younger than 65 with underlying medical conditions.
Controversially, Dr. Walensky contradicted the CDC’s own Advisory Committee on Immunization Practices (ACIP) by also recommending that people who are at greater risk of COVID exposure due to occupation or institutional setting—including healthcare workers and teachers—receive a booster shot. Earlier Thursday, ACIP members voted down a recommendation to provide boosters to healthcare workers, despite the FDA’s endorsement of that approach earlier in the week.
By Friday morning, President Biden announced he would soon get a booster shot himself, urging those eligible to do so, and re-emphasizing the administration’s primary focus on delivering first doses to those still unvaccinated. There will be more to come on boosters: the FDA and CDC guidance only applies to those who received the Pfizer-BioNTech vaccine at least six months ago; boosters for the Moderna and Johnson & Johnson vaccines are still under review.
This week’s saga caps a month of back-and-forth between public health officials, the White House, and the medical community, following Biden’s August promise—considered by many to be premature—that boosters would be broadly available starting September 20th. The inclusion of healthcare workers in the booster campaign is welcome news; we were flummoxed by ACIPs decision to bypass that critical segment, given mounting hospital staffing shortages amid the surging Delta variant.
More broadly, we’re increasingly distressed by the relatively uncoordinated and poorly-managed communication approach of the Biden administration on vaccines—particularly following a campaign in which competence was touted as a key advantage over the previous administration.
Exactly 300 years ago, in 1721, Benjamin Franklin and his fellow American colonists faced a deadly smallpox outbreak. Their varying responses constitute an eerily prescient object lesson for today’s world, similarly devastated by a virus and divided over vaccination three centuries later.
As a microbiologist and a Franklin scholar, we see some parallels between then and now that could help governments, journalists and the rest of us cope with the coronavirus pandemic and future threats.
What was new, at least to Boston, was a simple procedure that could protect people from the disease. It was known as “variolation” or “inoculation,” and involved deliberately exposing someone to the smallpox “matter” from a victim’s scabs or pus, injecting the material into the skin using a needle. This approach typically caused a mild disease and induced a state of “immunity” against smallpox.
Even today, the exact mechanism is poorly understood and not muchresearch on variolation has been done. Inoculation through the skin seems to activate an immune response that leads to milder symptoms and less transmission, possibly because of the route of infection and the lower dose. Since it relies on activating the immune response with live smallpox variola virus, inoculation is different from the modern vaccination that eradicated smallpox using the much less harmful but related vaccinia virus.
Known primarily as a Congregational minister, Mather was also a scientist with a special interest in biology. He paid attention when Onesimus told him “he had undergone an operation, which had given him something of the smallpox and would forever preserve him from it; adding that it was often used” in West Africa, where he was from.
Inspired by this information from Onesimus, Mather teamed up with a Boston physician, Zabdiel Boylston, to conduct a scientific study of inoculation’s effectiveness worthy of 21st-century praise. They found that of the approximately 300 people Boylston had inoculated, 2% had died, compared with almost 15% of those who contracted smallpox from nature.
The findings seemed clear: Inoculation could help in the fight against smallpox. Science won out in this clergyman’s mind. But others were not convinced.
Stirring up controversy
A local newspaper editor named James Franklin had his own affliction – namely an insatiable hunger for controversy. Franklin, who was no fan of Mather, set about attacking inoculation in his newspaper, The New-England Courant.
One article from August 1721 tried to guilt readers into resisting inoculation. If someone gets inoculated and then spreads the disease to someone else, who in turn dies of it, the article asked, “at whose hands shall their Blood be required?” The same article went on to say that “Epidemeal Distempers” such as smallpox come “as Judgments from an angry and displeased God.”
In contrast to Mather and Boylston’s research, the Courant’s articles were designed not to discover, but to sow doubt and distrust. The argument that inoculation might help to spread the disease posits something that was theoretically possible – at least if simple precautions were not taken – but it seems beside the point. If inoculation worked, wouldn’t it be worth this small risk, especially since widespread inoculations would dramatically decrease the likelihood that one person would infect another?
Franklin, the Courant’s editor, had a kid brother apprenticed to him at the time – a teenager by the name of Benjamin.
Historians don’t know which side the younger Franklin took in 1721 – or whether he took a side at all – but his subsequent approach to inoculation years later has lessons for the world’s current encounter with a deadly virus and a divided response to a vaccine.
That he was capable of overcoming this inclination shows Benjamin Franklin’s capacity for independent thought, an asset that would serve him well throughout his life as a writer, scientist and statesman. While sticking with social expectations confers certain advantages in certain settings, being able to shake off these norms when they are dangerous is also valuable. We believe the most successful people are the ones who, like Franklin, have the intellectual flexibility to choose between adherence and independence.
Perhaps the inoculation controversy of 1721 had helped him to understand an unfortunate phenomenon that continues to plague the U.S. in 2021: When people take sides, progress suffers. Tribes, whether long-standing or newly formed around an issue, can devote their energies to demonizing the other side and rallying their own. Instead of attacking the problem, they attack each other.
Franklin, in fact, became convinced that inoculation was a sound approach to preventing smallpox. Years later he intended to have his son Francis inoculated after recovering from a case of diarrhea. But before inoculation took place, the 4-year-old boy contracted smallpox and died in 1736. Citing a rumor that Francis had died because of inoculation and noting that such a rumor might deter parents from exposing their children to this procedure, Franklin made a point of setting the record straight, explaining that the child had “receiv’d the Distemper in the common Way of Infection.”
Writing his autobiography in 1771, Franklin reflected on the tragedy and used it to advocate for inoculation. He explained that he “regretted bitterly and still regret” not inoculating the boy, adding, “This I mention for the sake of parents who omit that operation, on the supposition that they should never forgive themselves if a child died under it; my example showing that the regret may be the same either way, and that, therefore, the safer should be chosen.”
A scientific perspective
A final lesson from 1721 has to do with the importance of a truly scientific perspective, one that embraces science, facts and objectivity.
Inoculation was a relatively new procedure for Bostonians in 1721, and this lifesaving method was not without deadly risks. To address this paradox, several physicians meticulously collected data and compared the number of those who died because of natural smallpox with deaths after smallpox inoculation. Boylston essentially carried out what today’s researchers would call a clinical study on the efficacy of inoculation. Knowing he needed to demonstrate the usefulness of inoculation in a diverse population, he reported in a short book how he inoculated nearly 300 individuals and carefully noted their symptoms and conditions over days and weeks.
The recent emergency-use authorization of mRNA-based and viral-vector vaccines for COVID-19 has produced a vast array of hoaxes, false claims and conspiracy theories, especially in various social media. Like 18th-century inoculations, these vaccines represent new scientific approaches to vaccination, but ones that are based on decades of scientific research and clinical studies.
We suspect that if he were alive today, Benjamin Franklin would want his example to guide modern scientists, politicians, journalists and everyone else making personal health decisions.Like Mather and Boylston, Franklin was a scientist with a respect for evidence and ultimately for truth.
When it comes to a deadly virus and a divided response to a preventive treatment, Franklin was clear what he would do. It doesn’t take a visionary like Franklin to accept the evidence of medical science today.
In this last episode of our six-part series on vaccinations, supported by the National Institute for Health Care Management Foundation, we cover vaccine development – particularly in the context of the current global pandemic. We discuss the timeline of Covid-19 vaccine development and the mRNA vaccine approach.
She grew up in Hungary, daughter of a butcher. She decided she wanted to be a scientist, although she had never met one. She moved to the United States in her 20s, but for decades never found a permanent position, instead clinging to the fringes of academia.
Now Katalin Kariko, 66, known to colleagues as Kati, has emerged as one of the heroes of Covid-19 vaccine development. Her work, with her close collaborator, Dr. Drew Weissman of the University of Pennsylvania, laid the foundation for the stunningly successful vaccines made by Pfizer-BioNTech and Moderna.
For her entire career, Dr. Kariko has focused on messenger RNA, or mRNA — the genetic script that carries DNA instructions to each cell’s protein-making machinery. She was convinced mRNA could be used to instruct cells to make their own medicines, including vaccines.
But for many years her career at the University of Pennsylvania was fragile. She migrated from lab to lab, relying on one senior scientist after another to take her in. She never made more than $60,000 a year.
By all accounts intense and single-minded, Dr. Kariko lives for “the bench” — the spot in the lab where she works. She cares little for fame. “The bench is there, the science is good,” she shrugged in a recent interview. “Who cares?”
Dr. Anthony Fauci, director of the National Institutes of Allergy and infectious Diseases, knows Dr. Kariko’s work. “She was, in a positive sense, kind of obsessed with the concept of messenger RNA,” he said.
Dr. Kariko’s struggles to stay afloat in academia have a familiar ring to scientists. She needed grants to pursue ideas that seemed wild and fanciful. She did not get them, even as more mundane research was rewarded.
“When your idea is against the conventional wisdom that makes sense to the star chamber, it is very hard to break out,” said Dr. David Langer, a neurosurgeon who has worked with Dr. Kariko.
Dr. Kariko’s ideas about mRNA were definitely unorthodox. Increasingly, they also seem to have been prescient.
“It’s going to be transforming,” Dr. Fauci said of mRNA research. “It is already transforming for Covid-19, but also for other vaccines. H.I.V. — people in the field are already excited. Influenza, malaria.”
‘I Felt Like a God’
For Dr. Kariko, most every day was a day in the lab. “You are not going to work — you are going to have fun,” her husband, Bela Francia, manager of an apartment complex, used to tell her as she dashed back to the office on evenings and weekends. He once calculated that her endless workdays meant she was earning about a dollar an hour.
For many scientists, a new discovery is followed by a plan to make money, to form a company and get a patent. But not for Dr. Kariko. “That’s the furthest thing from Kate’s mind,” Dr. Langer said.
She grew up in the small Hungarian town of Kisujszallas. She earned a Ph.D. at the University of Szeged and worked as a postdoctoral fellow at its Biological Research Center.
In 1985, when the university’s research program ran out of money, Dr. Kariko, her husband, and 2-year-old daughter, Susan, moved to Philadelphia for a job as a postdoctoral student at Temple University. Because the Hungarian government only allowed them to take $100 out of the country, she and her husband sewed £900 (roughly $1,246 today) into Susan’s teddy bear. (Susan grew up to be a two-time Olympic gold medal winner in rowing.)
When Dr. Kariko started, it was early days in the mRNA field. Even the most basic tasks were difficult, if not impossible. How do you make RNA molecules in a lab? How do you get mRNA into cells of the body?
In 1989, she landed a job with Dr. Elliot Barnathan, then a cardiologist at the University of Pennsylvania. It was a low-level position, research assistant professor, and never meant to lead to a permanent tenured position. She was supposed to be supported by grant money, but none came in.
She and Dr. Barnathan planned to insert mRNA into cells, inducing them to make new proteins. In one of the first experiments, they hoped to use the strategy to instruct cells to make a protein called the urokinase receptor. If the experiment worked, they would detect the new protein with a radioactive molecule that would be drawn to the receptor.
“Most people laughed at us,” Dr. Barnathan said.
One fateful day, the two scientists hovered over a dot-matrix printer in a narrow room at the end of a long hall. A gamma counter, needed to track the radioactive molecule, was attached to a printer. It began to spew data.
Their detector had found new proteins produced by cells that were never supposed to make them — suggesting that mRNA could be used to direct any cell to make any protein, at will.
“I felt like a god,” Dr. Kariko recalled.
She and Dr. Barnathan were on fire with ideas. Maybe they could use mRNA to improve blood vessels for heart bypass surgery. Perhaps they could even use the procedure to extend the life span of human cells.
Dr. Barnathan, though, soon left the university, accepting a position at a biotech firm, and Dr. Kariko was left without a lab or financial support. She could stay at Penn only if she found another lab to take her on. “They expected I would quit,” she said.
Universities only support low-level Ph.D.s for a limited amount of time, Dr. Langer said: “If they don’t get a grant, they will let them go.” Dr. Kariko “was not a great grant writer,” and at that point “mRNA was more of an idea,” he said.
But Dr. Langer knew Dr. Kariko from his days as a medical resident, when he had worked in Dr. Barnathan’s lab. Dr. Langer urged the head of the neurosurgery department to give Dr. Kariko’s research a chance. “He saved me,” she said.
Dr. Langer thinks it was Dr. Kariko who saved him — from the kind of thinking that dooms so many scientists.
Working with her, he realized that one key to real scientific understanding is to design experiments that always tell you something, even if it is something you don’t want to hear. The crucial data often come from the control, he learned — the part of the experiment that involves a dummy substance for comparison.
“There’s a tendency when scientists are looking at data to try to validate their own idea,” Dr. Langer said. “The best scientists try to prove themselves wrong. Kate’s genius was a willingness to accept failure and keep trying, and her ability to answer questions people were not smart enough to ask.”
Dr. Langer hoped to use mRNA to treat patients who developed blood clots following brain surgery, often resulting in strokes. His idea was to get cells in blood vessels to make nitric oxide, a substance that dilates blood vessels, but has a half-life of milliseconds. Doctors can’t just inject patients with it.
He and Dr. Kariko tried their mRNA on isolated blood vessels used to study strokes. It failed. They trudged through snow in Buffalo, N.Y., to try it in a laboratory with rabbits prone to strokes. Failure again.
And then Dr. Langer left the university, and the department chairman said he was leaving as well. Dr. Kariko again was without a lab and without funds for research.
A meeting at a photocopying machine changed that. Dr. Weissman happened by, and she struck up a conversation. “I said, ‘I am an RNA scientist — I can make anything with mRNA,’” Dr. Kariko recalled.
Dr. Weissman told her he wanted to make a vaccine against H.I.V. “I said, ‘Yeah, yeah, I can do it,’” Dr. Kariko said.
Despite her bravado, her research on mRNA had stalled. She could make mRNA molecules that instructed cells in petri dishes to make the protein of her choice. But the mRNA did not work in living mice.
“Nobody knew why,” Dr. Weissman said. “All we knew was that the mice got sick. Their fur got ruffled, they hunched up, they stopped eating, they stopped running.”
It turned out that the immune system recognizes invading microbes by detecting their mRNA and responding with inflammation. The scientists’ mRNA injections looked to the immune system like an invasion of pathogens.
But with that answer came another puzzle. Every cell in every person’s body makes mRNA, and the immune system turns a blind eye. “Why is the mRNA I made different?” Dr. Kariko wondered.
A control in an experiment finally provided a clue. Dr. Kariko and Dr. Weissman noticed their mRNA caused an immune overreaction. But the control molecules, another form of RNA in the human body — so-called transfer RNA, or tRNA — did not.
A molecule called pseudouridine in tRNA allowed it to evade the immune response. As it turned out, naturally occurring human mRNA also contains the molecule.
Added to the mRNA made by Dr. Kariko and Dr. Weissman, the molecule did the same — and also made the mRNA much more powerful, directing the synthesis of 10 times as much protein in each cell.
The idea that adding pseudouridine to mRNA protected it from the body’s immune system was a basic scientific discovery with a wide range of thrilling applications. It meant that mRNA could be used to alter the functions of cells without prompting an immune system attack.
“We both started writing grants,” Dr. Weissman said. “We didn’t get most of them. People were not interested in mRNA. The people who reviewed the grants said mRNA will not be a good therapeutic, so don’t bother.’”
Leading scientific journals rejected their work. When the research finally was published, in Immunity, it got little attention.
Dr. Weissman and Dr. Kariko then showed they could induce an animal — a monkey — to make a protein they had selected. In this case, they injected monkeys with mRNA for erythropoietin, a protein that stimulates the body to make red blood cells. The animals’ red blood cell counts soared.
The scientists thought the same method could be used to prompt the body to make any protein drug, like insulin or other hormones or some of the new diabetes drugs. Crucially, mRNA also could be used to make vaccines unlike any seen before.
Instead of injecting a piece of a virus into the body, doctors could inject mRNA that would instruct cells to briefly make that part of the virus.
“We talked to pharmaceutical companies and venture capitalists. No one cared,” Dr. Weissman said. “We were screaming a lot, but no one would listen.”
Eventually, though, two biotech companies took notice of the work: Moderna, in the United States, and BioNTech, in Germany. Pfizer partnered with BioNTech, and the two now help fund Dr. Weissman’s lab.
‘Oh, It Works’
Soon clinical trials of an mRNA flu vaccine were underway, and there were efforts to build new vaccines against cytomegalovirus and the Zika virus, among others. Then came the coronavirus.
Researchers had known for 20 years that the crucial feature of any coronavirus is the spike protein sitting on its surface, which allows the virus to inject itself into human cells. It was a fat target for an mRNA vaccine.
Chinese scientists posted the genetic sequence of the virus ravaging Wuhan in January 2020, and researchers everywhere went to work. BioNTech designed its mRNA vaccine in hours; Moderna designed its in two days.
The idea for both vaccines was to introduce mRNA into the body that would briefly instruct human cells to produce the coronavirus’s spike protein. The immune system would see the protein, recognize it as alien, and learn to attack the coronavirus if it ever appeared in the body.
The vaccines, though, needed a lipid bubble to encase the mRNA and carry it to the cells that it would enter. The vehicle came quickly, based on 25 years of work by multiple scientists, including Pieter Cullis of the University of British Columbia.
Scientists also needed to isolate the virus’s spike protein from the bounty of genetic data provided by Chinese researchers. Dr. Barney Graham, of the National Institutes of Health, and Jason McClellan, of the University of Texas at Austin, solved that problem in short order.
Testing the quickly designed vaccines required a monumental effort by companies and the National Institutes of Health. But Dr. Kariko had no doubts.
On Nov. 8, the first results of the Pfizer-BioNTech study came in, showing that the mRNA vaccine offered powerful immunity to the new virus. Dr. Kariko turned to her husband. “Oh, it works,” she said. “I thought so.”
To celebrate, she ate an entire box of Goobers chocolate-covered peanuts. By herself.
Dr. Weissman celebrated with his family, ordering takeout dinner from an Italian restaurant, “with wine,” he said. Deep down, he was awed.
“My dream was always that we develop something in the lab that helps people,” Dr. Weissman said. “I’ve satisfied my life’s dream.”
Dr. Kariko and Dr. Weissman were vaccinated on Dec. 18 at the University of Pennsylvania. Their inoculations turned into a press event, and as the cameras flashed, she began to feel uncharacteristically overwhelmed.
A senior administrator told the doctors and nurses rolling up their sleeves for shots that the scientists whose research made the vaccine possible were present, and they all clapped. Dr. Kariko wept.
Things could have gone so differently, for the scientists and for the world, Dr. Langer said. “There are probably many people like her who failed,” he said.
A new report out later today concludes that basic scientific research plays an essential role in creating companies that later produce thousands of jobs and billions in economic value.
Why it matters: The report uses thepandemic — and especially the rapid development of new mRNA vaccines — to show how basic research funding from the government lays the necessary groundwork for economically valuable companies down the road.
By the numbers: The Science Coalition — a nonprofit group that represents 50 of the nation’s top private and public research universities — identified 53 companies that have spun off from federally funded university research.
Those companies — which range from pharmaceutical startups to agriculture firms — have contributed more than $1.3 billion to U.S. GDP between 2015 and 2019, while supporting the creation of more than 100,000 jobs.
What they’re saying:“The COVID-19 pandemic has shown that the need for the federal government to continue investing in fundamental research is far from theoretical,” says John Latini, president of the Science Coalition. “Consistent, sustained, robust federal funding is how science evolves.”
The National Oceanic and Atmospheric Administration would see its budget rise to a record high of $6.9 billion, including $800 millionreserved for climate research.
The catch: The Biden budget proposal is just that, and it will ultimately be up to Congress to decide how much to allocate to research agencies.
Context: Government research funding is vital because private money tends to go to applied research. But without basic research — the lifeblood of science — the U.S. risks missing out on potentially world-changing innovations in the future.
The long-term value of that funding can be seen in the story of Katalin Kariko, an obscure biomedical researcher who labored for years on mRNA with little reward — until the pandemic, when her work helped provide the foundation for mRNA COVID-19 vaccines.
The bottom line: Because its ultimate payoff might lay years in the future, it’s easy to see basic research funding as a waste — until the day comes when we need it.
I had been staring her in the eyes, as she had ordered, but when a doctor on my other side began jabbing me with a needle, I started to turn my head. “Don’t look at it,” the first doctor said. I obeyed.
This was in early August in New Orleans, where I had signed up to be a participant in the clinical trial for the Pfizer-BioNTech COVID-19 vaccine. It was a blind study, which meant I was not supposed to know whether I had gotten the placebo or the real vaccine. I asked the doctor if I would really been able to tell by looking at the syringe. “Probably not,” she answered, “but we want to be careful. This is very important to get right.”
I became a vaccine guinea pig because, in addition to wanting to be useful, I had a deep interest in the wondrous new roles now being played by RNA, the genetic material that is at the heart of new types of vaccines, cancer treatments and gene-editing tools. I was writing a book on the Berkeley biochemist Jennifer Doudna. She was a pioneer in determining the structure of RNA, which helped her and her doctoral adviser figure out how it could be the origin of all life on this planet. Then she and a colleague invented an RNA-guided gene-editing tool, which won them the 2020 Nobel Prize in Chemistry.
The tool is based on a system that bacteria use to fight viruses. Bacteria develop clustered repeated sequences in their DNA, known as CRISPRs, that can remember dangerous viruses and then deploy RNA-guided scissors to destroy them. In other words, it’s an immune system that can adapt itself to fight each new wave of viruses—just what we humans need. Now, with the recently approved Pfizer-BioNTech vaccine and a similar one from Moderna being slowly rolled out across the U.S. and Europe, RNA has been deployed to make a whole new type of vaccine that will, when it reaches enough people, change the course of the pandemic.
Up until last year, vaccines had not changed very much, at least in concept, for more than two centuries. Most have been modeled on the discovery made in 1796 by the English doctor Edward Jenner, who noticed that many milkmaids were immune to smallpox. They had all been infected by a form of pox that afflicts cows but is relatively harmless to humans, and Jenner surmised that the cowpox had given them immunity to smallpox. So he took some pus from a cowpox blister, rubbed it into scratches he made in the arm of his gardener’s 8-year-old son and then (this was in the days before bioethics panels) exposed the kid to smallpox. He didn’t become ill.
Before then, inoculations were done by giving patients a small dose of the actual smallpox virus, hoping that they would get a mild case and then be immune. Jenner’s great advance was to use a related but relatively harmless virus. Ever since, vaccinations have been based on the idea of exposing a patient to a safe facsimile of a dangerous virus or other germ. This is intended to kick the person’s adaptive immune system into gear. When it works, the body produces antibodies that will, sometimes for many years, fend off any infection if the real germ attacks.
One approach is to inject a safely weakened version of the virus. These can be good teachers, because they look very much like the real thing. The body responds by making antibodies for fighting them, and the immunity can last a lifetime. Albert Sabin used this approach for the oral polio vaccine in the 1950s, and that’s the way we now fend off measles, mumps, rubella and chicken pox.
At the same time Sabin was trying to develop a vaccine based on a weakened polio virus, Jonas Salk succeeded with a safer approach: using a killed or inactivated virus. This type of vaccine can still teach a person’s immune system how to fight off the live virus but is less likely to cause serious side effects. Two Chinese companies, Sinopharm and Sinovac, have used this approach to develop vaccines for COVID-19 that are now in limited use in China, the UAE and Indonesia.
Another traditional approach is to inject a subunit of the virus, such as one of the proteins that are on the virus’s coat. The immune system will then remember these, allowing the body to mount a quick and robust response when it encounters the actual virus. The vaccine against the hepatitis B virus, for example, works this way. Using only a fragment of the virus means that they are safer to inject into a patient and easier to produce, but they are often not as good at producing long-term immunity. The Maryland-based biotech Novavax is in late-stage clinical trials for a COVID-19 vaccine using this approach, and it is the basis for one of the two vaccines already being rolled out in Russia.
The plague year of 2020 will be remembered as the time when these traditional vaccines were supplanted by something fundamentally new:genetic vaccines, which deliver a gene or piece of genetic code into human cells. The genetic instructions then cause the cells to produce, on their own, safe components of the target virus in order to stimulate the patient’s immune system.
For SARS-CoV-2—the virus that causes COVID-19—the target component is its spike protein, which studs the outer envelope of the virus and enables it to infiltrate human cells. One method for doing this is by inserting the desired gene, using a technique known as recombinant DNA, into a harmless virus that can deliver the gene into human cells. To make a COVID vaccine, a gene that contains instructions for building part of a coronavirus spike protein is edited into the DNA of a weakened virus like an adenovirus, which can cause the common cold. The idea is that the re-engineered adenovirus will worm its way into human cells, where the new gene will cause the cells to make lots of these spike proteins. As a result, the person’s immune system will be primed to respond rapidly if the real coronavirus strikes.
This approach led to one of the earliest COVID vaccine candidates, developed at the aptly named Jenner Institute of the University of Oxford. Scientists there engineered the spike-protein gene into an adenovirus that causes the common cold in chimpanzees, but is relatively harmless in humans.
The lead researcher at Oxford is Sarah Gilbert. She worked on developing a vaccine for Middle East respiratory syndrome (MERS) using the same chimp adenovirus. That epidemic waned before her vaccine could be deployed, but it gave her a head start when COVID-19 struck. She already knew that the chimp adenovirus had successfully delivered into humans the gene for the spike protein of MERS. As soon as the Chinese published the genetic sequence of the new coronavirus in January 2020, she began engineering its spike-protein gene into the chimp virus, waking each day at 4 a.m.
Her 21-year-old triplets, all of whom were studying biochemistry, volunteered to be early testers, getting the vaccine and seeing if they developed the desired antibodies. (They did.) Trials in monkeys conducted at a Montana primate center in March also produced promising results.
Bill Gates, whose foundation provided much of the funding, pushed Oxford to team up with a major company that could test, manufacture and distribute the vaccine. So Oxford forged a partnership with AstraZeneca, the British-Swedish pharmaceutical company. Unfortunately, the clinical trials turned out to be sloppy, with the wrong doses given to some participants, which led to delays. Britain authorized it for emergency use at the end of December, and the U.S. is likely to do so in the next two months.
Johnson & Johnson is testing a similar vaccine that uses a human adenovirus, rather than a chimpanzee one, as the delivery mechanism to carry a gene that codes for making part of the spike protein. It’s a method that has shown promise in the past, but it could have the disadvantage that humans who have already been exposed to that adenovirus may have some immunity to it. Results from its clinical trial are expected later this month.
In addition, two other vaccines based on genetically engineered adenoviruses are now in limited distribution: one made by CanSino Biologics and being used on the military in China and another named Sputnik V from the Russian ministry of health.
There is another way to get genetic material into a human cell and cause it to produce the components of a dangerous virus, such as the spike proteins, that can stimulate the immune system. Instead of engineering the gene for the component into an adenovirus, you can simply inject the genetic code for the component into humans as DNA or RNA.
Let’s start with DNA vaccines. Researchers at Inovio Pharmaceuticals and a handful of other companies in 2020 created a little circle of DNA that coded for parts of the coronavirus spike protein. The idea was that if it could get inside the nucleus of a cell, the DNA could very efficiently churn out instructions for the production of the spike-protein parts, which serve to train the immune system to react to the real thing.
The big challenge facing a DNA vaccine is delivery.How can you get the little ring of DNA not only into a human cell but into the nucleus of the cell? Injecting a lot of the DNA vaccine into a patient’s arm will cause some of the DNA to get into cells, but it’s not very efficient.
Some of the developers of DNA vaccines, including Inovio, tried to facilitate the delivery into human cells through a method called electroporation, which delivers electrical shock pulses to the patient at the site of the injection. That opens pores in the cell membranes and allows the DNA to get in. The electric pulse guns have lots of tiny needles and are unnerving to behold. It’s not hard to see why this technique is unpopular, especially with those on the receiving end. So far, no easy and reliable delivery mechanism has been developed for getting DNA vaccines into the nucleus of human cells.
That leads us to the molecule that has proven victorious in the COVID vaccine race and deserves the title of TIME magazine’s Molecule of the Year: RNA. Its sibling DNA is more famous. But like many famous siblings, DNA doesn’t do much work. It mainly stays bunkered down in the nucleus of our cells, protecting the information it encodes. RNA, on the other hand, actually goes out and gets things done. The genes encoded by our DNA are transcribed into snippets of RNA that venture out from the nucleus of our cells into the protein-manufacturing region. There, this messenger RNA (mRNA) oversees the assembly of the specified protein. In other words, instead of just sitting at home curating information, it makes real products.
Scientists including Sydney Brenner at Cambridge and James Watson at Harvard first identified and isolated mRNA molecules in 1961. But it was hard to harness them to do our bidding, because the body’s immune system often destroyed the mRNA that researchers engineered and attempted to introduce into the body. Then in 2005, a pair of researchers at the University of Pennsylvania, Katalin Kariko and Drew Weissman, showed how to tweak a synthetic mRNA molecule so it could get into human cells without being attacked by the body’s immune system.
When the COVID-19 pandemic hit a year ago, two innovative young pharmaceutical companies decided to try to harness this role played by messenger RNA: the German company BioNTech, which formed a partnership with the U.S. company Pfizer; and Moderna, based in Cambridge, Mass. Their mission was to engineer messenger RNA carrying the code letters to make part of the coronavirus spike protein—a string that begins CCUCGGCGGGCA … —and to deploy it in human cells.
BioNTech was founded in 2008 by the husband-and-wife team of Ugur Sahin and Ozlem Tureci, who met when they were training to be doctors in Germany in the early 1990s. Both were from Turkish immigrant families, and they shared a passion for medical research, so much so that they spent part of their wedding day working in the lab. They founded BioNTech with the goal of creating therapies that stimulate the immune system to fight cancerous cells. It also soon became a leader in devising medicines that use mRNA in vaccines against viruses.
In January 2020, Sahin read an article in the medical journal Lancet about a new coronavirus in China. After discussing it with his wife over breakfast, he sent an email to the other members of the BioNTech board saying that it was wrong to believe that this virus would come and go as easily as MERS and SARS. “This time it is different,” he told them.
BioNTech launched a crash project to devise a vaccine based on RNA sequences, which Sahin was able to write within days, that would cause human cells to make versions of the coronavirus’s spike protein. Once it looked promising, Sahin called Kathrin Jansen, the head of vaccine research and development at Pfizer. The two companies had been working together since 2018 to develop flu vaccines using mRNA technology, and he asked her whether Pfizer would want to enter a similar partnership for a COVID vaccine. “I was just about to call you and propose the same thing,” Jansen replied. The deal was signed in March.
By then, a similar mRNA vaccine was being developed by Moderna, a much smaller company with only 800 employees. Its chair and co-founder, Noubar Afeyan, a Beirut-born Armenian who immigrated to the U.S., had become fascinated by mRNA in 2010, when he heard a pitch from a group of Harvard and MIT researchers. Together they formed Moderna, which initially focused on using mRNA to try to develop personalized cancer treatments, but soon began experimenting with using the technique to make vaccines against viruses.
In January 2020, Afeyan took one of his daughters to a restaurant near his office in Cambridge to celebrate her birthday. In the middle of the meal, he got an urgent text message from the CEO of his company, Stéphane Bancel, in Switzerland. So he rushed outside in the freezing temperature, forgetting to grab his coat, to call him back.
Bancel said that he wanted to launch a project to use mRNA to attempt a vaccine against the new coronavirus. At that point, Moderna had more than 20 drugs in development but none had even reached the final stage of clinical trials. Nevertheless, Afeyan instantly authorized him to start work. “Don’t worry about the board,” he said. “Just get moving.” Lacking Pfizer’s resources, Moderna had to depend on funding from the U.S. government. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, was supportive. “Go for it,” he declared. “Whatever it costs, don’t worry about it.”
It took Bancel and his Moderna team only two days to create the RNA sequences that would produce the spike protein, and 41 days later, it shipped the first box of vials to the National Institutes of Health to begin early trials. Afeyan keeps a picture of that box on his cell phone.
An mRNA vaccine has certain advantages over a DNA vaccine, which has to use a re-engineered virus or other delivery mechanism to make it through the membrane that protects the nucleus of a cell. The RNA does not need to get into the nucleus. It simply needs to be delivered into the more-accessible outer region of cells, the cytoplasm, which is where proteins are constructed.
The Pfizer-BioNTech and Moderna vaccines do so by encapsulating the mRNA in tiny oily capsules, known as lipid nanoparticles.Moderna had been working for 10 years to improve its nanoparticles.This gave it one advantage over Pfizer-BioNTech: its particles were more stable and did not have to be stored at extremely low temperatures.
By November, the results of the Pfizer-BioNTech and Moderna late-stage trials came back with resounding findings: both vaccines were more than 90% effective. A few weeks later, with COVID-19 once again surging throughout much of the world, they received emergency authorization from the U.S. Food and Drug Administration and became the vanguard of the biotech effort to beat back the pandemic.
The ability to code messenger RNA to do our bidding will transform medicine. As with the COVID vaccines, we can instruct mRNA to cause our cells to make antigens—molecules that stimulate our immune system—that could protect us against many viruses, bacteria, or other pathogens that cause infectious disease. In addition, mRNA could in the future be used, as BioNTech and Moderna are pioneering, to fight cancer. Harnessing a process called immunotherapy, the mRNA can be coded to produce molecules that will cause the body’s immune system to identify and kill cancer cells.
RNA can also be engineered, as Jennifer Doudna and others discovered, to target genes for editing. Using the CRISPR system adapted from bacteria, RNA can guide scissors-like enzymes to specific sequences of DNA in order to eliminate or edit a gene. This technique has already been used in trials to cure sickle cell anemia. Now it is also being used in the war against COVID. Doudna and others have created RNA-guided enzymes that can directly detect SARS-CoV-2 and eventually could be used to destroy it.
More controversially, CRISPR could be used to create “designer babies” with inheritable genetic changes. In 2018, a young Chinese doctor used CRISPR to engineer twin girls so they did not have the receptor for the virus that causes AIDS. There was an immediate outburst of awe and then shock. The doctor was denounced, and there were calls for an international moratorium on inheritable gene edits. But in the wake of the pandemic, RNA-guided genetic editing to make our species less receptive to viruses may someday begin to seem more acceptable.
Throughout human history, we have been subjected to wave after wave of viral and bacterial plagues. One of the earliest known was the Babylon flu epidemic around 1200 B.C. The plague of Athens in 429 B.C. killed close to 100,000 people, the Antonine plague in the 2nd century killed 5 million, the plague of Justinian in the 6th century killed 50 million, and the Black Death of the 14th century took almost 200 million lives, close to half of Europe’s population.
The COVID-19 pandemic that killed more than 1.8 million people in 2020 will not be the final plague. However, thanks to the new RNA technology, our defenses against most future plagues are likely to be immensely faster and more effective. As new viruses come along, or as the current coronavirus mutates, researchers can quickly recode a vaccine’s mRNA to target the new threats. “It was a bad day for viruses,” Moderna’s chair Afeyan says about the Sunday when he got the first word of his company’s clinical trial results. “There was a sudden shift in the evolutionary balance between what human technology can do and what viruses can do. We may never have a pandemic again.”
The invention of easily reprogrammable RNA vaccines was a lightning-fast triumph of human ingenuity, but it was based on decades of curiosity-driven research into one of the most fundamental aspects of life on planet earth: how genes are transcribed into RNA that tell cells what proteins to assemble. Likewise, CRISPR gene-editing technology came from understanding the way that bacteria use snippets of RNA to guide enzymes to destroy viruses. Great inventions come from understanding basic science. Nature is beautiful that way.
AstraZeneca on Monday became the third pharmaceutical company to announce remarkable results from late-stage trials of a coronavirus vaccine, saying that its candidate, developed by Oxford University, is up to 90 percent effective.
This is the third straight week to begin with buoyant scientific news that suggests, even as coronavirus cases surge to devastating levels in many countries, an end to the pandemic is in sight.
Pfizer and its German partner BioNTech and Moderna have each reported vaccines that are 95 percent effective in clinical trials. A direct comparison to the Oxford-AstraZeneca vaccine is complicated, due to the trial design, but the vaccine may be a more realistic option for much of the world, as it is likely to be cheaper and does not need to be stored at subzero temperatures.
Peter Piot, director of the London School of Hygiene & Tropical Medicine, who was instrumental in the battle against AIDS, said the positive results from three vaccine candidates cannot be overestimated.
“2020 will be remembered for the many lives lost from covid-19, lockdowns and the U.S. election. Science should now be added to this list,” said Piot, adding, “the only way to stop covid-19 in its tracks is having multiple effective and safe vaccines that can be deployed all around the world and in vast quantities.”
“I’m totally delighted,” said Hildegund C.J. Ertl, a vaccine expert at the Wistar Institute in Philadelphia. Adding to the results from Pfizer and Moderna, “what it tells me is this virus can be beaten quite easily: 90 to 95 percent efficacy is something we’d dream about for influenza virus, and we’d never get it.”
The Oxford-AstraZeneca team said in a video conference with journalists that its candidate offered 90 percent protection against the virus when a subject received a half-dose, followed with a full dose one month later. Efficacy was lower — 62 percent — when subjects received two full doses a month apart. The interim results, therefore, averaged to 70 percent efficacy.
Andrew Pollard, chief investigator of the Oxford trial, said the findings showed the vaccine would save many lives.
“Excitingly, we’ve found that one of our dosing regimens may be around 90 percent effective, and if this dosing regimen is used, more people could be vaccinated with planned vaccine supply,” he said.
Britain has preordered 100 million doses — which at a dose and a half per person would cover most of its population. The United States has ordered 300 million.
The results have yet to be peer-reviewed or published, and will be scrutinized by regulators. Many questions remain, including whether the vaccine can reduce transmission of the virus by people without symptoms, which would have repercussions for how soon people could stop wearing masks. It is also unclear how long the immunity from the vaccine lasts — a crucial question.
Sarah Gilbert, a lead Oxford researcher, cautioned that the dose-and-a-half regimen would have to be more closely studied to be fully understood. But she said the first half-dose might be priming a person’s immune system just enough, and that the second booster then encourages the body to produce a robust defense against sickness and infection.
AstraZeneca and Oxford have been conducting Phase 3 clinical trials worldwide, with the most recent data coming from an interim analysis based on 131 coronavirus infections in Britain and Brazil among 10,000 volunteers, with half getting the vaccine and half getting a placebo.
The company said it would present the results to Britain’s health-care products regulators immediately and would seek approval to fine-tune its clinical trials in the United States, to further assess the half-dose shot followed by a booster.
Because the vaccine is already in production, if approved, the first 4 million doses could be ready in December, and 40 million could be delivered in the first quarter of 2021, company executives said. By the spring, the company and its global partners in India, Brazil, Russia and the United States could be cranking out 100 million to 200 million doses a month.
British Health Secretary Matt Hancock said “should all that go well, the bulk of the rollout will be in the new year.”
In a statement to Parliament, Prime Minister Boris Johnson said that vaccines were “edging ever closer to liberating us from the virus, demonstrating emphatically that this is not a pandemic without end. We can take great heart from today’s news, which has the makings of a wonderful British scientific achievement.”
World markets have rallied on optimistic vaccine news, though shares in AstraZeneca were down Monday on the London stock exchange.
No participants who received the vaccine developed severe cases or required hospitalization, AstraZeneca said Monday. The drugmaker also said that no “serious safety events” were reported in connection with the vaccine, which was typically “well tolerated” by participants regardless of their dosing levels or ages.
The vaccine uses a harmless cold virus that typically infects chimpanzees to deliver to the body’s cells the genetic code of the spike protein that dots the outside of the coronavirus. That teaches the body’s immune system to recognize and block the real virus.
Although the reason the regimen with an initial half-dose worked better remains to be teased out, Ertl said that it could be related to the fact that the body’s immune system can develop a defense system to block the harmless virus that’s used to deliver the spike protein’s code. Giving a smaller initial dose may lessen those defenses, and make the vaccine more effective.
Several other vaccines in late-stage development use a similar technology, harnessing a harmless virus to deliver a payload that will teach the immune system how to fight off the real thing — including the Johnson & Johnson vaccine, the Russian vaccine being developed by the Gamaleya Research Institute and the vaccine made by CanSino Biologics in China.
While the results released by AstraZeneca indicate somewhat lower efficacy than Pfizer and Moderna, the vaccine can be stored and transported at normal refrigerated conditions for up to six months. That could make it significantly easier to roll out than Pfizer’s vaccine, which has to be stored at minus-70 degrees Celsius, or Moderna’s, which is stable in refrigerated conditions for only 30 days and must be frozen at minus-20 degrees Celsius after that.
The Oxford-AstraZeneca vaccine was first developed in a small laboratory running on a shoestring budget by Gilbert at Oxford and her team. The university kicked in 1 million pounds ($1.3 million) and then sought a manufacturing partner, before settling on AstraZeneca.
“We wanted to ensure there wouldn’t be any profiteering off the pandemic,” said Louise Richardson, the university’s vice chancellor, so that their vaccine would be widely distributed “and wouldn’t just be for the wealthy and the first world.”
The scientists said that although it appeared to be a race, or a competition, among the front-running vaccine developers, no one company could produce by itself the millions of doses needed to end the pandemic.
“We don’t have enough supply for the whole planet,” Pollard said, adding that the important message is that today there are at least three highly effective, safe vaccines, that also appear to work well among the elderly, and that they are produced using different technologies, ensuring the quickest route to manufacture the billions of doses that will be necessary.
Pollard said it is “unclear why” the different vaccines were producing different results, and he said he and the scientific community awaited full data sets from all the clinical trials to fully understand what is going on. He said different studies were also using different end points to describe efficacy.
“At this moment we can’t fully explain the differences,” Pollard said. “It’s critical to understand what everyone is measuring.”
• Scientists are expressing cautious optimism that a vaccine can be ready to go by the late spring of 2021, although it’s unclear how much longer it would take to distribute the vaccine widely.
• Two possible vaccines are in phase 3 clinical trials; once those trials are completed, they would be candidates for approval. Another eight vaccines have begun phase 2 trials. And more than 100 other vaccines that haven’t begun clinical trials are in the pipeline.
• The Food and Drug Administration recently produced guidelines for the minimum effectiveness of vaccines seeking the agency’s approval. Vaccine officials say these guidelines are important to ensure public confidence in vaccines.
More than four months into the coronavirus pandemic, how close is the U.S. and the world to a safe and effective vaccine? Scientists say they see steady progress and are expressing cautious optimism that a vaccine could be ready by spring of 2021.
Generally, a vaccine trial has several phases. In an initial phase, the vaccine is given to 20 to 100 healthy volunteers. The focus in this phase is to make sure the vaccine is safe, and to note any side effects.
In the second phase, there are hundreds of volunteers. In addition to monitoring safety, researchers try to determine whether shots produce an immune-system response.
The third phase involves thousands of patients. This phase continues the goals of the first two, but adds a focus on how effective the vaccine is. This phase also collects data on more unusual negative side effects.
In ordinary circumstances, these phases take years to complete. But for coronavirus, the timeline is being shortened. This has spurred more public-private partnerships and significantly increased funding.
Here’s a rundown of the 13 vaccine candidates that are furthest along in the clinical phases:
Coronavirus vaccines that are the furthest along:
The three vaccine candidates that are furthest along are both in phase 3.
One is being developed by researchers at Oxford University in the U.K. It uses a weakened version of a virus that causes common colds in chimpanzees. Researchers then added proteins, known as antigens, from the novel coronavirus, in the hope that these could prime the human immune system to fight the virus once it encounters it.
Another candidate in a phase 3 trial is being developed in China. It uses a killed, and thus safe, version of the novel coronavirus to spur an immune reaction.
And on July 15, the biotech company Moderna, which is partnering with the National Institutes of Health, announced that it would be moving to phase 3 within two weeks.
Two others have made it as far as phase 2, while eight others are finishing their phase 1 trials while also beginning phase 2 trials.
These candidates are being developed by a mix of corporations and institutions in several countries. These efforts seek to leverage a range of different technologies.
One uses RNA material that provides the instructions for a body to produce the needed antigens itself. This is a relatively untested approach to vaccination, but if it works, it has aspects that could make it easier to manufacture. Another approach is similar, but uses DNA instead of RNA.
One U.S. biotech firm, Novavax, is receiving federal funding to produce a vaccine that uses a lab-made protein to inspire an immune response.
Beyond these, another 10 vaccine candidates are in phase 1 clinical trials, while another 140 haven’t reached the clinical phase yet.
Having so many potential vaccines this far along is impressive, experts say, given the short time scientists have known about the novel coronavirus.
“Overall, the pace of development and advancement to Phase 3 trials is impressive,” said Matthew B. Laurens, associate professor at the University of Maryland School of Medicine’s Center for Vaccine Development and Global Health. “The public-private partnerships have been highly successful and are achieving goals for rapid vaccine development.”
In addition, the fact that several types of vaccine approaches are being tested means we aren’t putting all of our eggs in one basket.
“We will need several candidates should any one of these experience difficulties in manufacturing or show a safety signal when implemented in larger numbers of people,” Laurens said.
Meanwhile, at a time of rising public skepticism of government and vaccines, the Food and Drug Administration recently released additional guidelines on vaccine effectiveness. The new guidance requires vaccines to prevent or decrease the severity of the disease at least 50% of the time if they are to win the agency’s approval.
The FDA guidelines “reaffirmed the very rigorous FDA process for approving any vaccine. That gives a great deal of reassurance that this was going to be handled by the book,” said William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt University Medical Center. “The more we talk about doing things fast, the more the public thinks, ‘They’re probably cutting corners.’”
How fast will we have access to a workable vaccine?
In early April, Kathleen M. Neuzil, director of the University of Maryland’s vaccine center, told PolitiFact that if all went well, there might be five or six vaccines in trials within six months. Now, three and a half months later, there are two to three times that number.
Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, and other officials have remained consistent in their estimation of the timeline: 12 to 18 months from the start of the pandemic, or roughly the late spring of 2021.
Schaffner told PolitiFact that he continues to see the first quarter of 2021 as a reasonable target. “I think that’s where the needle is pointing,” he said.
It remains to be seen how fast vaccines can be manufactured and distributed once approved for general use. Officials are also grappling with which Americans will get access first. So it’s unclear how long a person would have to wait to get vaccinated.
Laurens said he is not overly concerned about the distribution, because that is something that officials have long experience with. “Well-established programs exist for vaccine distribution, including for seasonal vaccination of large numbers of individuals,” he said.
Another hopeful sign, Schaffner said, is that the coronavirus itself seems to be relatively stable. There had been concern that the novel coronavirus, like many other viruses, is mutating over time. If the virus changes enough, that could become a problem that bedevils vaccine researchers.
But so far, that hasn’t happened. Even if evidence emerges that mutations are making the virus more transmissible, or that a new variant is making people sicker, that shouldn’t affect the vaccine process. “The central core of the virus would remain the same,” Schaffner said.
During the past month, there has been relatively little news about how much progress is being made on particular vaccines. Schaffner is not worried by the relative quiet.
“In a vaccine trial, if there’s an adverse safety finding, the guillotine comes down and that trial is stopped,” he said. “So quiet is good, because we’d know if something bad happens.”
Heavy hearts soared Monday with news that Moderna’s Covid-19 vaccine candidate — the frontrunner in the American market — seemed to be generating an immune response in Phase 1 trial subjects. The company’s stock valuation also surged, hitting $29 billion, an astonishing feat for a company that currently sells zero products.
But was there good reason for so much enthusiasm? Several vaccine experts asked by STAT concluded that, based on the information made available by the Cambridge, Mass.-based company, there’s really no way to know how impressive — or not — the vaccine may be.
While Moderna blitzed the media, it revealed very little information — and most of what it did disclose were words, not data. That’s important: If you ask scientists to read a journal article, they will scour data tables, not corporate statements. With science, numbers speak much louder than words.
Even the figures the company did release don’t mean much on their own, because critical information — effectively the key to interpreting them — was withheld.
Experts suggest we ought to take the early readout with a big grain of salt. Here are a few reasons why.
The silence of the NIAID
The National Institute for Allergy and Infectious Diseases has partnered with Moderna on this vaccine. Scientists at NIAID made the vaccine’s construct, or prototype, and the agency is running the Phase 1 trial. This week’s Moderna readout came from the earliest of data from the NIAID-led Phase 1.
NIAID doesn’t hide its light under a bushel. The institute generally trumpets its findings, often offering director Anthony Fauci — who, fair enough, is pretty busy these days — or other senior personnel for interviews.
But NIAID did not put out a press release Monday and declined to provide comment on Moderna’s announcement.
The n = 8 thing
The company’s statement led with the fact that all 45 subjects (in this analysis) who received doses of 25 micrograms (two doses each), 100 micrograms (two doses each), or a 250 micrograms (one dose) developed binding antibodies.
Later, the statement indicated that eight volunteers — four each from the 25-microgram and 100-microgram arms — developed neutralizing antibodies. Of the two types, these are the ones you’d really want to see.
We don’t know results from the other 37 trial participants. This doesn’t mean that they didn’t develop neutralizing antibodies. Testing for neutralizing antibodies is more time-consuming than other antibody tests and must be done in a biosecurity level 3 laboratory. Moderna disclosed the findings from eight subjects because that’s all it had at that point. Still, it’s a reason for caution.
Separately, while the Phase 1 trial included healthy volunteers ages 18 to 55 years, the exact ages of these eight people are unknown. If, by chance, they mostly clustered around the younger end of the age spectrum, you might expect a better response to the vaccine than if they were mostly from the senior end of it. And given who is at highest risk from the SARS-CoV-2 coronavirus, protecting older adults is what Covid-19 vaccines need to do.
There’s no way to know how durable the response will be
The report of neutralizing antibodies in subjects who were vaccinated comes from blood drawn two weeks after they received their second dose of vaccine.
“That’s very early. We don’t know if those antibodies are durable,” said Anna Durbin, a vaccine researcher at Johns Hopkins University.
There’s no real way to contextualize the findings
Moderna stated that the antibody levels seen were on a par with — or greater than, in the case of the 100-microgram dose — those seen in people who have recovered from Covid-19 infection.
But studies have shown antibody levels among people who have recovered from the illness vary enormously; the range that may be influenced by the severity of a person’s disease. John “Jack” Rose, a vaccine researcher from Yale University, pointed STAT to a study from China that showed that, among 175 recovered Covid-19 patients studied, 10 had no detectable neutralizing antibodies. Recovered patients at the other end of the spectrum had really high antibody levels.
So though the company said the antibody levels induced by vaccine were as good as those generated by infection, there’s no real way to know what that comparison means.
STAT asked Moderna for information on the antibody levels it used as a comparator. The response: That will be disclosed in an eventual journal article from NIAID, which is part of the National Institutes of Health.
“The convalescent sera levels are not being detailed in our data readout, but would be expected in a downstream full data exposition with NIH and its academic collaborators,” Colleen Hussey, the company’s senior manager for corporate communications, said in an email.
Durbin was struck by the wording of the company’s statement, pointing to this sentence: “The levels of neutralizing antibodies at day 43 were at or above levels generally seen in convalescent sera.”
“I thought: Generally? What does that mean?” Durbin said. Her question, for the time being, can’t be answered.
Rose said the company should disclose the information. “When a company like Moderna with such incredibly vast resources says they have generated SARS-2 neutralizing antibodies in a human trial, I would really like to see numbers from whatever assay they are using,” he said.
Moderna’s approach to disclosure
The company has not yet brought a vaccine to market, but it has a variety of vaccines for infectious diseases in its pipeline. It doesn’t publish on its work in scientific journals. What is known has been disclosed through press releases. That’s not enough to generate confidence within the scientific community.
“My guess is that their numbers are marginal or they would say more,” Rose said about the company’s SARS-2 vaccine, echoing a suspicion that others have about some of the company’s other work.
“I do think it’s a bit of a concern that they haven’t published the results of any of their ongoing trials that they mention in their press release. They have not published any of that,” Durbin noted.
Still, she characterized herself as “cautiously optimistic” based on what the company has said so far.
“I would like to see the data to make my own interpretation of the data. But I think it is at least encouraging that we’ve seen immune responses with this RNA vaccine that we haven’t seen with previous RNA vaccines for other pathogens. Whether it’s going to be enough, we don’t know,” Durbin said.
Moderna has been more forthcoming with data on at least one of its other vaccine candidates. In a statement issued in January about a Phase 1 trial for its cytomegalovirus (CMV) vaccine, it quantified how far over baseline measures antibody levels rose in vaccines.
A vaccine manufacturer is reporting preliminary data suggesting its COVID-19 vaccine is safe, and appears to be eliciting in test subjects the kind of immune response capable of preventing disease.
Moderna, Inc., of Cambridge, Mass., developed the vaccine in collaboration with the National Institute of Allergy and Infectious Diseases. The results reported Monday come from an initial analysis of a Phase I study primarily designed to see if the vaccine is safe.
The company reports no serious side-effects; however, modest side-effects included redness at the injection site, headache, fever and flu-like symptoms, although none of these lasted more than a day.
The first 45 volunteers for the vaccine trial were divided into three groups, with each group getting a different dose of the vaccine. All groups got an initial shot, followed by a booster shot a month later.
In addition to safety, the company also looked at the vaccine’s ability to induce antibodies to the coronavirus — what’s known as its immunogenicity. It did, for all subjects at all dose levels. In addition, eight of the subjects were tested for the presence of neutralizing antibodies that prevent the virus from infecting cells in the laboratory. All eight did.
The Food and Drug Administration has given Moderna the green light to begin a Phase II study expected to enroll an additional 600 volunteers — half older than 55 — to provide additional immunogenicity data. The company hopes by July to begin a Phase III study, aimed at showing that the vaccine can actually prevent disease.
The Moderna vaccine is made using messenger RNA, or mRNA, a molecule containing the genetic instructions to make a protein on the coronavirus surface that is recognized by our immune systems. Although mRNA vaccines have been studied for several years, so far none has been licensed by the FDA.
The advantage of mRNA vaccines over more traditional vaccines is they can be made quickly. The company says it was just 63 days from the time Chinese scientists revealed the genetic sequence to the time a vaccine was injected into the first volunteer.
Moderna’s is one of about a dozen COVID-19 vaccine candidates that have begun studies in humans.