It was a relatively quiet week on the COVID front—so quiet that President Biden held his first White House press conference last week and wasn’t asked a single question about the pandemic, which continues to be a race between vaccinations and virus variants.
Not that nothing happened this week: it was a rocky week for AstraZeneca, which was hoping to change the narrative over its vaccine, which has stumbled in its rollout in Europe, by reporting positive results from US trials.
After a press release announcing that the vaccine was found to be 79 percent effective against symptomatic COVID, an independent review board called the results into question, pointing out that the report was based on data that had not been fully updated. That earned a swift and unusual rebuke from the National Institutes of Health (NIH), forcing the company to correct its findings—to 76 percent.
A relatively minor difference, but the dust-up served to further undermine confidence in the company’s COVID jab, especially troubling in Europe where hesitancy and distribution have been a vexing problem, and concerns about blood clots associated with the AstraZeneca shot caused several countries to pause inoculations. Given the supply of already-approved vaccines from other manufacturers in the US, it’s not clear that the AstraZeneca shot will play a big role here, but it is critical in other parts of the world, especially as part of the global COVAX initiative targeted at developing countries, since the vaccine can be stored at normal refrigerator temperatures.
The company’s set-to with American regulators also highlighted another challenge that’s become common during the COVID pandemic: conducting scientific review by press release, as the global emergency has required the otherwise slow-moving research community to move at lightning pace.
Meanwhile, back at that relatively dull White House press conference, one piece of encouraging news:President Biden doubled his “first 100 days” goal for vaccinations to 200M shots, a goal that seemswholly achievable, given that 2.5M Americans are being vaccinated every day, on average.
More than half of adults in the U.S. (55%) say they’ve already gotten one dose of Covid-19 vaccine or they’re eager to get one as soon as they can, an increase in acceptance from January (47%), a new poll reports. About 1 in 5 people are waiting to see how the vaccine rollout goes, but don’t rule out vaccination. Another 1 in 5 people are more reluctant: 7% would get vaccinated only if required by work, school, or some other activity, and 15% say no to vaccine under any circumstance. The increase in eagerness spans all demographic groups, but Black adults and young adults under age 30 were most likely to say they want to wait and see.
The Johnson & Johnson coronavirus vaccine prevented 100% of hospitalizations and deaths in clinical trials, the company said today.
Why it matters:The single-dose vaccine could speed up the vaccinations of America’s vulnerable populations, as new variants spread.
By the numbers:
Overall: 66% effective in preventing moderate to severe COVID in nearly 44,000 participants in Phase 3 trials across eight countries.
In the U.S.: 72% effective.
In South Africa, home of a more aggressive variant: 57% effective.
What they’re saying:
Former CDC director Tom Frieden on the Axios Re:Cap podcast: “It has a lot of advantages, easier to store, easier to make.”
Former FDA commissioner Scott Gottlieb: “The J&J vaccine turns in a fantastic result. We now have three highly effective vaccines. This vaccine showed sustained (and increasing!) immune protection over time, perhaps from a robust early induction of memory immune cells (CD4 and CD8).”
What’s next:J&J is expected to apply for an emergency use authorization next week, the N.Y. Times reports.
“Federal regulators are also still waiting on data from Johnson & Johnson’s new manufacturing facility in Baltimore that prove it can mass-produce the vaccine. The company is counting on that factory to help reach its contractual pledge to the federal government of 100 million doses by the end of June.”
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.
A hospital employee outside Milwaukee deliberately spoiled more than 500 doses of coronavirus vaccine by removing 57 vials from a pharmacy refrigerator, hospital officials announced Wednesday, as local police said they were investigating the incident with the help of federal authorities.
Initiating an internal review on Monday, hospital officials said they were initially “led to believe” the incident was caused by “inadvertent human error.” The vials were removed Friday and most were discarded Saturday, with only a few still safe to administer, according to an earlier statement from the health system. Each vial has enough for 10 vaccinations but can sit at room temperature for only 12 hours.
Two days later, the employee acknowledged having “intentionally removed the vaccine from refrigeration,” the hospital, Aurora Medical Center in Grafton, Wis., said in a statement late Wednesday.
The employee, who has not been identified, was fired, the hospital said. Its statement did not address the worker’s motives but said “appropriate authorities” were promptly notified.
Wednesday night, police in Grafton, a village of about 12,000 that lies 20 miles north of Milwaukee, said they were investigating along with the FBI and the Food and Drug Administration. In a statement, the local police department said it had learned of the incident from security services at Aurora Health Care’s corporate office in Milwaukee. The system serves eastern Wisconsin and northern Illinois, and includes 15 hospitals and more than 150 clinics.
Leonard Peace, an FBI spokesman in Milwaukee, would not comment on the Bureau’s involvement but said of the episode, “We’re aware of it.” The FDA did not immediately respond to a request for comment.
The tampering will delay inoculation for hundreds of people, Aurora Health officials said, in a state where 3,170 new cases were reported and 40 people died Wednesday of covid-19, the disease caused by the coronavirus, according to The Washington Post’s coronavirus tracker.
“We are more than disappointed that this individual’s actions will result in a delay of more than 500 people receiving the vaccine,” the health system said in a statement.
The Wisconsin incident comes as states continue to grapple with a bumpy rollout of the first doses of the Moderna and Pfizer-BioNTech vaccines, which were approved less than a month ago and prioritized for health-care workers and residents and staff of long-term care facilities. So far, distribution has lagged well behind federal projections, raising doubts about whether the outgoing administration will meet its already revised goal of 20 million vaccines distributed by the end of the year.
As of Wednesday, the Centers for Disease Control and Prevention said 12.4 million doses of the vaccine had been distributed across the United States, but only 2.6 million of those had been administered.(This means that just 1 in 125 Americans has received the first dose of the vaccine.) Trump administration officials have said these numbers lag behind the actual pace of vaccination, which they also vowed would accelerate starting next week.
The Moderna and Pfier-BioNTech vaccines, the first two regimens to gain regulatory approval for emergency use, are two-shot protocols with intricate logistical requirements. Moderna’s vaccine doesn’t require subarctic temperatures, as does the Pfizer product, but it does need to be kept cold. It can be stored at freezer temperatures for six months, the company says, and kept at regular refrigerated conditions for 30 days. It can be maintained at room temperature for only 12 hours, though, and can’t be refrozen once thawed.
Complex storage requirements are among the reasons state officials are imploring providers to administer vaccine quickly once it is received.
In its original statement, Aurora Health said it had successfully vaccinated about 17,000 people over the previous 12 days. Its initial review, it said, had found that the 57 vials were simply not returned to the refrigerator after “temporarily being removed to access other items.”
The hospital apologized, saying, “We are clearly disappointed and regret this happened.”
It is not clear what motive the employee may have had to spoil the vaccine doses. The hospital said it would release more details about its investigation Thursday.
If all goes according to plan, health care workers and individuals at high risk for severe illness from COVID-19 could be vaccinated as early as December.
Experts predict that the broader public could start being vaccinated in April.
The distribution of the vaccine could present some challenges for state and federal governments. That or any other unexpected events could delay the vaccine’s distribution.
When drugmaker Pfizer announced that its new vaccine was highly effective at preventing COVID-19, it raised hopes that the coronavirus pandemic could be nearing its end.
In a Nov. 9 press release, the company and its partner BioNTech claimed that an early analysis of clinical trial data found that inoculated individuals experienced 90% fewer cases of symptomatic COVID-19 than those who had received a placebo.
These results surpassed expectations. For months, experts have warned that a new vaccine might only be 60% effective. If Pfizer’s analysis is accurate — and it has yet to produce official scientific documentation — the new vaccine would offer a level of protection equal to that of highly effective vaccines for diseases such as measles.
Experts told us that Pfizer’s announcement is cause for optimism. However, the country, and the world, still have a way to go before coronavirus vaccines become available to ordinary Americans.
Here’s what we know about when the vaccine might be distributed and what that process could look like. What’s next for Pfizer’s vaccine?
If the information in the press release is accurate, Pfizer will likely be the first company to come up with a vaccine that meets the Food and Drug Administration’s requirements for distribution.
To get approval from the FDA, Pfizer has to gather two months of safety data on clinical trial participants to gauge whether the treatment has any negative side effects. The company will reach the two-month benchmark in the third week of November. Barring any unexpected developments, it will then submit its vaccine to the FDA for emergency use authorization, a special provision allowing the use of an unapproved product during a state of emergency.
After Pfizer submits its data to the FDA, the agency will analyze it to see if it’s sufficient to begin distribution. After approval from the FDA, the vaccine would be assessed by the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices. The Advisory Committee will then issue a recommendation to the CDC, which will make the final ruling about whether to distribute the vaccine.
This might sound intricate, but James Blumenstock, the chief program officer for health security at the Association of State and Territorial Health Officials, said that the vaccine could probably be approved by the FDA and the CDC in a matter of days rather than weeks.
“Both agencies are standing ready and will give these requests and this assessment the highest level of priority just for expediency’s sake,” he said.
What this means is that high-priority Americans, such as health care workers, could be vaccinated as early as December. What a vaccine rollout might look like.
Pfizer predicts that it will be able to manufacture only 50 million doses for global consumption by the end of the year, enough to vaccinate 25 million people. (The world’s population is about 7.8 billion.)
With a limited number of doses available, the eventual rollout of a vaccine would likely consist of two phases. During the first phase, U.S. health care workers, emergency responders and individuals at higher risk of severe illness would be eligible for vaccination. If all goes according to plan, the first phase will commence sometime in December.
During the second phase, the vaccine would become available to the broader public. Most experts told us that they expect the second phase to start sometime in April, although the date would vary depending on Pfizer’s vaccine production rates and whether other companies get their vaccines greenlit by the FDA and CDC. The state of other vaccines
Pfizer’s announcement bodes well for other vaccine candidates, said Matthew B. Laurens, an associate professor of pediatrics at the University of Maryland School of Medicine’s Center for Vaccine Development and Global Health.
Pfizer’s vaccine uses genetic material, known as mRNA, that provides the instructions for a body to produce coronavirus proteins, known as antigens, in the hope that these could prime the human immune system to fight the virus. The biotechnology company Moderna is also manufacturing a vaccine that uses mRNA and is set to receive trial data by the end of November.
Other companies in the United States and Europe producing a vaccine include Novavax, which plans to start clinical trials in the U.S. and Mexico by the end of November; Johnson & Johnson, which recently resumed testing its vaccine candidate after a brief pause; and AstraZeneca, which expects to have clinical trial data by the end of the year.
The more companies there are that are able to produce a vaccine, the quicker the vaccine will become widely available, experts say.
Vaccine presents potential distribution hurdles
The CDC will be in charge of the distribution process, with involvement from the U.S. Defense Department, said Dr. Litjen Tan, chief strategy officer for the Immunization Action Coalition, which distributes information about vaccines to try to increase vaccination rates.
Vaccines would be manufactured and then transported to states, which will then pass the vaccine on to providers, such as hospitals. The McKesson Corp., which has received a federal contract to distribute the treatment, will assist pharmaceutical companies and the government with the shipping process.
Shipping the doses will present some challenges. Pfizer’s vaccine has complex and ultra-cold storage requirements that many hospitals, particularly those in hard-to-reach areas, won’t be able to meet.
The cold chain requirement “is an issue for Pfizer, but manufacturing and distribution are issues for all vaccines,” said Robert Finberg, a physician and infectious disease specialist at the University of Massachusetts Medical Center.
To surmount this hurdle, Pfizer plans to transport the vaccine in thermal shippers that can keep the vaccine at the necessary temperature of minus 70 degrees Celsius for about two weeks. However, the shippers themselves present additional problems for distribution, Tan said. Each shipment consists of five trays containing 975 doses of vaccine, and reducing the size of the shipment could dramatically raise the cost of distribution.
As a result, the states might initially prioritize shipping the vaccine to major hospitals rather than rural hospitals that service fewer patients in order to avoid waste.
Blumenstock told us that state and federal governments are working hard to make sure that all regions of the U.S. receive proportionate amounts of vaccine. However, he acknowledged that hospitals in remote areas that don’t service many patients could initially take longer to get the vaccine than a well-trafficked hospital in a heavily populated area.
“Outskirt hospitals won’t be ignored or marginalized, even if it takes more time and effort to get them the vaccine,” he said. “One of the primary principles will be equitable distribution, even when that means you need to take extraordinary measures for logistics, transportation, and handling.”
Overall, experts said that Pfizer’s announcement is a significant step forward. “I’m optimistic that we have a vaccine that’s safe and effective,” said Tan. “And I’m glad that what we’re dealing with now is the problem of how to get it to the public.”
A promising vaccine developed by drug giant Pfizer and German biotechnology firm BioNTech would need to be stored at ultracold temperatures that experts say could make it far more difficult to distribute than other potential vaccines.
Pfizer announced Monday that an interim analysis had shown the vaccine was more than 90 percent effective, news that was greeted with near universal celebration among experts.
But the Pfizer vaccine is relatively unusual as it has to be stored and transported at an ultracold temperature of around -94 Fahrenheit (-70 Celsius), significantly complicating the process of getting the vaccine to people.
Ultracold storage is “is not necessarily routinely available in most health centers even in the U.K., let alone globally,” Michael Head, a fellow in global health at the University of Southampton said in a statement.
Vaccines often require some kind of cold storage to remain effective; some candidates for a coronavirus vaccine need to be held at cooler temperatures like 26 Fahrenheit (2 Celsius). They need to be kept this temperature not only while in storage but also while being delivering on planes and trucks.
The Pfizer vaccine would be considerably colder, requiring more than just refrigeration but something capable of producing freezing temperatures even during potential lengthy periods of transport. It has been done before, though at a smaller scale: A vaccine for the Ebola virus was notable for requiring ultracold storage. Pfizer has been preparing for the challenge by creating special containers that can last 10 days at -94 Fahrenheit, according to the Wall Street Journal.
Groups like the World Health Organization and UNICEF have said that countries need to improve their “cold chain” logistical networks to make sure vaccines can be distributed safely.The Associated Press reported last month that nearly 3 billion people live in areas where temperature-controlled storage is insufficient for the task.