What Will Make the Public Trust a COVID-19 Vaccine?
With a brighter future hanging on the hopes of an approved COVID-19 vaccine, is it possible to win over the minds of fearful citizens who challenge the value or safety of vaccination?
Globally, nine COVID-19 vaccines so far are being tested for safety in early phase human clinical trials.
It's a decades-old practice. With a dose injected into the arm of a healthy patient, doctors aim to prevent illness with a vaccine shot designed to trigger a person's immune system to fight serious infection without getting the disease.
This week, in fact, the U.S. frontrunner vaccine candidate, developed by Moderna, safely produced an immune response in the first eight healthy volunteers, the company announced. A large efficacy trial is planned to start in July. But if positive signals for safety and efficacy result from that trial, will that be enough to convince the public to broadly embrace a new vaccine?
"Throughout the history of vaccines there has always been a small vocal minority who don't believe vaccines work or don't trust the science," says sociologist and researcher Jennifer Reich, a professor at the University of Colorado in Denver and author of Calling the Shots: Why Parents Reject Vaccines.
Research indicates that only about 2 percent of the population say vaccines aren't necessary under any circumstance. Remarkably, a quarter to one third of American parents delay or reject the shots, not because they are anti-vaccine, but because they disapprove of the recommended timing or administration, says Reich.
Additionally, addressing distrust about how they come to market is key when talking to parents, workers or anyone targeted for a new vaccine, she says.
"When I talk to parents about why they reject vaccines for their kids, a lot of them say that they don't fully trust the process by which vaccines are regulated and tested," says Reich. "They don't trust that vaccine manufacturers -- which are for-profit companies -- are looking out for public health."
Balancing Act
Globally, nine COVID-19 vaccine candidates so far are being tested for safety in early phase human clinical trials and more than 100 are under development as scientists hustle to curtail the disease. Creating a new vaccine at a record pace requires a delicate balance of benefit and risk, says vaccinology expert Dr. Kathryn Edwards, professor of pediatrics in the division of infectious diseases at Vanderbilt University School of Medicine in Nashville, Tenn.
"We take safety very seriously," says Dr. Edwards. "We don't want something bad to happen, but we also realize that we have a terrible outbreak and we have a lot of people dying. We want to figure out how we can stop this."
In the U.S., all vaccine clinical trials have a data safety board of experts who monitor results for adverse reactions and red flags that should halt a study, notes Dr. Edwards. Any candidate that succeeds through safety and efficacy trials still requires review and approval by the Food and Drug Administration before a public launch.
Community vs. Individual
A major challenge to the deployment of a safe and effective coronavirus vaccine goes beyond the technical realm. A persistent all-out anti-vaccine sentiment has found a home and growing community on social media where conspiracies thrive. Main tenets of the movement are that vaccines are ineffective, unsafe and cause autism, despite abundant scientific evidence to the contrary.
Best-case scenario, more than one successful vaccine ascends with competing methods to achieve the same goal of preventing or lessening the severity of the COVID-19 virus.
In fact, widespread use of vaccines is considered by the U.S. Centers of Disease Control and Prevention to be one of the greatest public health achievements of the 20th Century. The World Health Organization estimates that between two million to three million deaths are avoided each year through immunization campaigns that employ vaccination to control life-threatening infectious diseases.
Most people reluctant to give their children vaccines, however, don't oppose them for everyone, but believe that they are a personal choice, says Reich.
"They think that vaccines are one strategy in personal health optimization, but they shouldn't be mandated for participation in any part of civil society," she says.
Vaccine hesitancy, like the teeter totter of social distancing acceptance, reflects the push and pull of individual versus community values, says Reich.
"A lot of people are saying, 'I take personal responsibility for my own health and I don't want a city or a county or state telling me what I should and shouldn't do,'" says Reich. "Then we also see calls for collective responsibility that says 'It's not your personal choice. This is about helping health systems function. This is about making sure vulnerable people are protected.'"
These same debates are likely to continue if a vaccine comes to market, she says.
Building Public Confidence
Reich offers solutions to address the conflict between embedded American norms and widespread embrace of an approved COVID-19 vaccine. Long-term goals: Stop blaming people when they get sick, treat illness as a community responsibility, make sick leave common for all workers, and improve public health systems.
"In the shorter run," says Reich, "health authorities and companies that might bring a vaccine to market need to work very hard to explain to the public why they should trust this vaccine and why they should use it."
The rush for a viable vaccine raises questions for consumers. To build public confidence, it's up to FDA reviewers, institutions and pharmaceutical companies to explain "what steps were skipped. What steps moved forward. How rigorous was safety testing. And to make that information clear to the public," says Reich.
Dr. Edwards says clinical trial timelines accelerated to test vaccines in humans make all the safeguards involved in the process that more compelling and important.
"There's no question we need a vaccine," she says. "But we also have to make sure that we don't harm people."
The Road Ahead
Think of manufacturing and distribution as key pitstops to keep the race for a vaccine on the road to the finish line. Both elements require substantial effort and consideration.
The speed of getting a vaccine to those who need it could hinge on the type of technology used to create it. Best-case scenario, more than one successful vaccine ascends with competing methods to achieve the same goal of preventing or lessening the severity of the COVID-19 virus.
Technological platforms fall into two basic camps, those that are proven and licensed for other viruses, and experimental approaches that may hold great promise but lack regulatory approval, says Maria Elena Bottazzi, co-director of Texas Children's Center for Vaccine Development at Baylor College of Medicine in Houston.
Moderna, for instance, employs an experimental technology called messenger RNA (mRNA) that has produced the encouraging early results in human safety trials, although some researchers criticized the company for not making the data public. The mRNA vaccine instructs cells to make copies of the key COVID-19 spike protein, with the goal of then triggering production of immune cells that can recognize and attack the virus if it ever invades the body.
"We were already seeing a lot of dissent around questions of individual freedoms and community responsibilities."
Scientists always look for ways to incorporate new technologies into drug development, says Bottazzi. On the other hand, the more basic and generic the technology, theoretically, the faster production could ramp up if a vaccine proves successful through all phases of clinical trials, she says.
"I don't want to develop a vaccine in my lab, but then I don't have anybody to hand it off to because my process is not suitable" for manufacturing or scalability, says Bottazzi.
Researchers at the Baylor lab hope to repurpose a shelved vaccine developed for the genetically similar SARS virus, with a strategy to leverage what is already known instead of "starting from scratch" to develop a COVID-19 vaccine. A recombinant protein technology similar to that used for an approved Hepatitis B vaccine lets scientists focus on identifying a suitable vaccine target without the added worry of a novel platform, says Bottazzi.
The Finish Line
If and when a COVID-19 vaccine is approved is anyone's guess. Announcing a plan to hasten vaccine development via a program dubbed Operation Warp Speed, President Trump said recently one could be available "hopefully" by the end of the year or early 2021.
Scientists urge caution, noting that safe vaccines can take 10 years or more to develop. If a rushed vaccine turns out to have safety and efficacy issues, that could add ammunition to the anti-vaccine lobby.
Emergence of a successful vaccine requires an "enormous effort" with many complex systems from the lab all the way to manufacturing enough capacity to handle a pandemic, says Bottazzi.
"At the same time, you're developing it, you're really carefully assessing its safety and ability to be effective," she says, so it's important "not to get discouraged" if it takes longer than a year or more.
To gauge if a vaccine works on a broad scale, it would have to be delivered into communities where the virus is active. There are examples in history of life-saving vaccines going first to people who could pay for them and not to those who needed them most, says Reich.
"Agencies are going to have to think about how those distribution decisions are going to be made and who is going to make them and that will go a certain way toward reassuring the public," says Reich.
A Gallup survey last year found that vaccine confidence, in general, remains high, with 86 percent of Americans believing that vaccines are safer than the diseases that they are designed to prevent. Still, recent news organization polls indicate that roughly 20 to 25 percent of Americans say they won't or are unlikely to get a COVID-19 vaccine if one becomes available.
Until the 1980s, every vaccine to hit the market was appreciated; a culture of questioning science didn't exist in the same way as today, notes Reich. Time passed and attitudes changed.
"We were already having robust arguments nationally about what counts as an expert, what's the role of the government in daily life," says Reich. "We were already seeing a lot of dissent around questions of individual freedoms and community responsibilities. COVID-19 did not create those conflicts, but they've definitely become more visible since we've moved into this pandemic."
Gene Transfer Leads to Longer Life and Healthspan
The naked mole rat won’t win any beauty contests, but it could possibly win in the talent category. Its superpower: fighting the aging process to live several times longer than other animals its size, in a state of youthful vigor.
It’s believed that naked mole rats experience all the normal processes of wear and tear over their lifespan, but that they’re exceptionally good at repairing the damage from oxygen free radicals and the DNA errors that accumulate over time. Even though they possess genes that make them vulnerable to cancer, they rarely develop the disease, or any other age-related disease, for that matter. Naked mole rats are known to live for over 40 years without any signs of aging, whereas mice live on average about two years and are highly prone to cancer.
Now, these remarkable animals may be able to share their superpower with other species. In August, a study provided what may be the first proof-of-principle that genetic material transferred from one species can increase both longevity and healthspan in a recipient animal.
There are several theories to explain the naked mole rat’s longevity, but the one explored in the study, published in Nature, is based on the abundance of large-molecule high-molecular mass hyaluronic acid (HMM-HA).
A small molecule version of hyaluronic acid is commonly added to skin moisturizers and cosmetics that are marketed as ways to keep skin youthful, but this version, just applied to the skin, won’t have a dramatic anti-aging effect. The naked mole rat has an abundance of the much-larger molecule, HMM-HA, in the chemical-rich solution between cells throughout its body. But does the HMM-HA actually govern the extraordinary longevity and healthspan of the naked mole rat?
To answer this question, Dr. Vera Gorbunova, a professor of biology and oncology at the University of Rochester, and her team created a mouse model containing the naked mole rat gene hyaluronic acid synthase 2, or nmrHas2. It turned out that the mice receiving this gene during their early developmental stage also expressed HMM-HA.
The researchers found that the effects of the HMM-HA molecule in the mice were marked and diverse, exceeding the expectations of the study’s co-authors. High-molecular mass hyaluronic acid was more abundant in kidneys, muscles and other organs of the Has2 mice compared to control mice.
In addition, the altered mice had a much lower incidence of cancer. Seventy percent of the control mice eventually developed cancer, compared to only 57 percent of the altered mice, even after several techniques were used to induce the disease. The biggest difference occurred in the oldest mice, where the cancer incidence for the Has2 mice and the controls was 47 percent and 83 percent, respectively.
With regard to longevity, Has2 males increased their lifespan by more than 16 percent and the females added 9 percent. “Somehow the effect is much more pronounced in male mice, and we don’t have a perfect answer as to why,” says Dr. Gorbunova. Another improvement was in the healthspan of the altered mice: the number of years they spent in a state of relative youth. There’s a frailty index for mice, which includes body weight, mobility, grip strength, vision and hearing, in addition to overall conditions such as the health of the coat and body temperature. The Has2 mice scored lower in frailty than the controls by all measures. They also performed better in tests of locomotion and coordination, and in bone density.
Gorbunova’s results show that a gene artificially transferred from one species can have a beneficial effect on another species for longevity, something that had never been demonstrated before. This finding is “quite spectacular,” said Steven Austad, a biologist at the University of Alabama at Birmingham, who was not involved in the study.
Just as in lifespan, the effects in various organs and systems varied between the sexes, a common occurrence in longevity research, according to Austad, who authored the book Methuselah’s Zoo and specializes in the biological differences between species. “We have ten drugs that we can give to mice to make them live longer,” he says, “and all of them work better in one sex than in the other.” This suggests that more attention needs to be paid to the different effects of anti-aging strategies between the sexes, as well as gender differences in healthspan.
According to the study authors, the HMM-HA molecule delivered these benefits by reducing inflammation and senescence (cell dysfunction and death). The molecule also caused a variety of other benefits, including an upregulation of genes involved in the function of mitochondria, the powerhouses of the cells. These mechanisms are implicated in the aging process, and in human disease. In humans, virtually all noncommunicable diseases entail an acceleration of the aging process.
So, would the gene that creates HMM-HA have similar benefits for longevity in humans? “We think about these questions a lot,” Gorbunova says. “It’s been done by injections in certain patients, but it has a local effect in the treatment of organs affected by disease,” which could offer some benefits, she added.
“Mice are very short-lived and cancer-prone, and the effects are small,” says Steven Austad, a biologist at the University of Alabama at Birmingham. “But they did live longer and stay healthy longer, which is remarkable.”
As for a gene therapy to introduce the nmrHas2 gene into humans to obtain a global result, she’s skeptical because of the complexity involved. Gorbunova notes that there are potential dangers in introducing an animal gene into humans, such as immune responses or allergic reactions.
Austad is equally cautious about a gene therapy. “What this study says is that you can take something a species does well and transfer at least some of that into a new species. It opens up the way, but you may need to transfer six or eight or ten genes into a human” to get the large effect desired. Humans are much more complex and contain many more genes than mice, and all systems in a biological organism are intricately connected. One naked mole rat gene may not make a big difference when it interacts with human genes, metabolism and physiology.
Still, Austad thinks the possibilities are tantalizing. “Mice are very short-lived and cancer-prone, and the effects are small,” he says. “But they did live longer and stay healthy longer, which is remarkable.”
As for further research, says Austad, “The first place to look is the skin” to see if the nmrHas2 gene and the HMM-HA it produces can reduce the chance of cancer. Austad added that it would be straightforward to use the gene to try to prevent cancer in skin cells in a dish to see if it prevents cancer. It would not be hard to do. “We don’t know of any downsides to hyaluronic acid in skin, because it’s already used in skin products, and you could look at this fairly quickly.”
“Aging mechanisms evolved over a long time,” says Gorbunova, “so in aging there are multiple mechanisms working together that affect each other.” All of these processes could play a part and almost certainly differ from one species to the next.
“HMM-HA molecules are large, but we’re now looking for a small-molecule drug that would slow it’s breakdown,” she says. “And we’re looking for inhibitors, now being tested in mice, that would hinder the breakdown of hyaluronic acid.” Gorbunova has found a natural, plant-based product that acts as an inhibitor and could potentially be taken as a supplement. Ultimately, though, she thinks that drug development will be the safest and most effective approach to delivering HMM-HA for anti-aging.
In recent years, researchers of Alzheimer’s have made progress in figuring out the complex factors that lead to the disease. Yet, the root cause, or causes, of Alzheimer’s are still pretty much a mystery.
In fact, many people get Alzheimer’s even though they lack the gene variant we know can play a role in the disease. This is a critical knowledge gap for research to address because the vast majority of Alzheimer’s patients don’t have this variant.
A new study provides key insights into what’s causing the disease. The research, published in Nature Communications, points to a breakdown over time in the brain’s system for clearing waste, an issue that seems to happen in some people as they get older.
Michael Glickman, a biologist at Technion – Israel Institute of Technology, helped lead this research. I asked him to tell me about his approach to studying how this breakdown occurs in the brain, and how he tested a treatment that has potential to fix the problem at its earliest stages.
Dr. Michael Glickman is internationally renowned for his research on the ubiquitin-proteasome system (UPS), the brain's system for clearing the waste that is involved in diseases such as Huntington's, Alzheimer's, and Parkinson's. He is the head of the Lab for Protein Characterization in the Faculty of Biology at the Technion – Israel Institute of Technology. In the lab, Michael and his team focus on protein recycling and the ubiquitin-proteasome system, which protects against serious diseases like Alzheimer’s, Parkinson’s, cystic fibrosis, and diabetes. After earning his PhD at the University of California at Berkeley in 1994, Michael joined the Technion as a Senior Lecturer in 1998 and has served as a full professor since 2009.
Dr. Michael Glickman