Thousands of Vaccine Volunteers Got a Dummy Shot. Should They Get the Real Deal Now?
The highly anticipated rollout of a COVID-19 vaccine poses ethical considerations: When will trial volunteers who got a placebo be vaccinated? And how will this affect the data in those trials?
It's an issue that vaccine manufacturers and study investigators are wrestling with as the Food and Drug Administration is expected to grant emergency use authorization this weekend to a vaccine developed by Pfizer and the German company BioNTech. Another vaccine, produced by Moderna, is nearing approval in the United States.
The most vulnerable—health care workers and nursing home residents—are deemed eligible to receive the initial limited supply in accordance with priority recommendations from the Centers for Disease Control and Prevention (CDC).
With health care workers constituting an estimated 20 percent of trial participants, this question also comes to the fore: "Is it now ethically imperative that we offer them the vaccine, those who have had placebo?" says William Schaffner, an infectious diseases physician at Vanderbilt University and an adviser to the CDC's immunization practices committee.
When a "gold-standard" measure becomes available, participants in the placebo group "would ordinarily be notified" of the strong public health recommendation to opt for immunization, says Johan Bester, interim assistant dean for biomedical science education and director of bioethics at the University of Nevada, Las Vegas School of Medicine.
"If a treatment or prevention exists that we know works, it is unethical to withhold it from people who would benefit from it just to answer a research question." This moral principle poses a quandary for ethicists and physicians alike, as they ponder possible paths to proceed with vaccination amid ongoing trials. Rigorous trials are double-blinded—neither the participants nor the investigators know who received the actual vaccine and who got a dummy injection.
"The intent of these trials is to follow these folks for up to two years," says Marci Drees, infection prevention officer and hospital epidemiologist for ChristianaCare in Wilmington, Delaware. At a minimum, she adds, researchers would prefer to monitor participants for six months.
"You can still follow safety over a long-term period of time without actually continuing to have a placebo group for comparison."
But in the midst of a pandemic, that may not be feasible. Prolonged exposure to the highly contagious and lethal virus could have dire consequences.
To avoid compromising the integrity of the blinded data, "there are some potentially creative solutions," Drees says. For instance, trial participants could receive the opposite of what they initially got, whether it was the vaccine or the placebo.
One factor in this decision-making process depends on when a particular trial is slated to conclude. If that time is approaching, the risk of waiting would be lower than if the trial is only halfway in progress, says Eric Lofgren, an epidemiologist at Washington State University who has studied the impact of COVID-19 in jails and at in-person sporting events.
Sometimes a study concludes earlier than the projected completion date. "All clinical trials have a data and safety monitoring board that reviews the interim results," Lofgren says. The board may halt a trial after finding evidence of harm, or when a treatment or vaccine has proven to be "sufficiently good," rendering it unethical to deprive the placebo group of its benefits.
The initial months of a trial are most crucial for assessing a vaccine's safety. Differences between the trial groups would be illuminating if fewer individuals who got the active vaccine contracted the virus and developed symptoms when compared to the placebo recipients. After that point, in vaccine-administered participants, "you can still follow safety over a long-term period of time without actually continuing to have a placebo group for comparison," says Dial Hewlett Jr., medical director for disease control at the Westchester County Department of Health in New York.
Even outside of a trial, safety is paramount and any severe side effects that occur will be closely monitored and investigated through national reporting networks. For example, regulators in the U.K. are investigating several rare but serious allergic reactions to the Pfizer vaccine given on Tuesday. The FDA has asked Pfizer to track allergic reactions in its safety monitoring plan, and some experts are proposing that Pfizer conduct a separate study of the vaccine on people with a history of severe allergies.
As the FDA eventually grants authorization to multiple vaccines, more participants are likely to leave trials and opt to be vaccinated. It is important that enough participants choose to stay in ongoing trials, says Nicole Hassoun, professor of philosophy at the State University of New York at Binghamton, where she directs the Global Health Impact program to extend medical access to the poor.
She's hopeful that younger participants and individuals without underlying medical conditions will make that determination. But the departure of too many participants at high risk for the virus would make it more difficult to evaluate the vaccine's safety and efficacy in those populations, Hassoun says, while acknowledging, "We can't have the best of both worlds."
Once a safe and effective vaccine is approved in the United States, "it would not be ethically appropriate to do placebo trials to test new vaccines."
One solution would entail allowing health care workers to exit a trial after a vaccine is approved, even though this would result in "a conundrum when the next group of people are brought forward to get the vaccine—whether they're people age 65 and older or they're essential workers, or whoever they are," says Vanderbilt physician Schaffner, who is a former board member of the Infectious Diseases Society of America. "All of a sudden, you'll have an erosion of the volunteers who are in the trial."
For now, one way or another, experts agree that current and subsequent trials should proceed. There is a compelling reason to identify additional vaccines with potentially greater effectiveness but with fewer side effects or less complex delivery methods that don't require storage at extremely low temperatures.
"Continuing with existing vaccine trials and starting others remains important," says Nir Eyal, professor and director of Rutgers University's Center for Population-Level Bioethics in New Brunswick, New Jersey. "We still need to tell how much proven vaccines block infections and how long their duration lasts. And populations around the world need vaccines that are easier to store and deliver, or simply cheaper."
But once a safe and effective vaccine is approved in the United States, "it would not be ethically appropriate to do placebo trials to test new vaccines," says bioethicist Bester at the University of Nevada, Las Vegas School of Medicine. "One possibility if a new vaccine emerges, is to test it against existing vaccines."
In a letter sent to trial volunteers in November, Pfizer and BioNTech committed to establishing "a process that would allow interested participants in the placebo group who meet the eligibility criteria for early access in their country to 'cross-over' to the vaccine group." The trial plans to continue monitoring all subjects regardless of whether people in the placebo group cross over, Pfizer said in a presentation to the FDA today. After Pfizer has collected six months of safety data, in April 2021, it plans to ask the FDA for full approval of the vaccine.
In the meantime, the company pledged to update volunteers as they obtain more input from regulatory authorities. "Thank you again for making a difference by being a part of this study," they wrote. "It is only through the efforts of volunteers like you that reaching this important milestone and developing a potential vaccine against COVID-19 is possible."
CORRECTION: An earlier version of this article mistakenly stated that the FDA would be granting emergency "approval" to the Pfizer/BioNTech vaccine, rather than "emergency use authorization." We regret the error.
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.
Here are the promising studies covered in this week's Friday Five, featuring interviews with Dr. Christopher Martens, director of the Delaware Center for Cogntiive Aging Research and professor of kinesiology and applied physiology at the University of Delaware, and Dr. Ilona Matysiak, visiting scholar at Iowa State University and associate professor of sociology at Maria Grzegorzewska University.
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As a child, Wendy Borsari participated in a health study at Boston Children’s Hospital. She was involved because heart disease and sudden cardiac arrest ran in her family as far back as seven generations. When she was 18, however, the study’s doctors told her that she had a perfectly healthy heart and didn’t have to worry.
A couple of years after graduating from college, though, the Boston native began to experience episodes of near fainting. During any sort of strenuous exercise, my blood pressure would drop instead of increasing, she recalls.
She was diagnosed at 24 with hypertrophic cardiomyopathy. Although HCM is a commonly inherited heart disease, Borsari’s case resulted from a rare gene mutation, the MYH7 gene. Her mother had been diagnosed at 27, and Borsari had already lost her grandmother and two maternal uncles to the condition. After her own diagnosis, Borsari spent most of her free time researching the disease and “figuring out how to have this condition and still be the person I wanted to be,” she says.
Then, her son was found to have the genetic mutation at birth and diagnosed with HCM at 15. Her daughter, also diagnosed at birth, later suffered five cardiac arrests.
That changed Borsari’s perspective. She decided to become a patient advocate. “I didn’t want to just be a patient with the condition,” she says. “I wanted to be more involved with the science and the biopharmaceutical industry so I could be active in helping to make it better for other patients.”
She consulted on patient advocacy for a pharmaceutical and two foundations before coming to a company called Tenaya in 2021.
“One of our core values as a company is putting patients first,” says Tenaya's CEO, Faraz Ali. “We thought of no better way to put our money where our mouth is than by bringing in somebody who is affected and whose family is affected by a genetic form of cardiomyopathy to have them make sure we’re incorporating the voice of the patient.”
Biomedical corporations and government research agencies are now incorporating patient advocacy more than ever, says Alice Lara, president and CEO of the Sudden Arrhythmia Death Syndromes Foundation in Salt Lake City, Utah. These organizations have seen the effectiveness of including patient voices to communicate and exemplify the benefits that key academic research institutions have shown in their medical studies.
“From our side of the aisle,” Lara says, “what we know as patient advocacy organizations is that educated patients do a lot better. They have a better course in their therapy and their condition, and understanding the genetics is important because all of our conditions are genetic.”
Founded in 2016, Tenaya is advancing gene therapies and small molecule drugs in clinical trials for both prevalent and rare forms of heart disease, says Ali, the CEO.
The firm's first small molecule, now in a Phase 1 clinical trial, is intended to treat heart failure with preserved ejection fraction, where the amount of blood pumped by the heart is reduced due to the heart chambers becoming weak or stiff. The condition accounts for half or more of all heart failure in the U.S., according to Ali, and is growing quickly because it's closely associated with diabetes. It’s also linked with metabolic syndrome, or a cluster of conditions including high blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol levels.
“We have a novel molecule that is first in class and, to our knowledge, best in class to tackle that, so we’re very excited about the clinical trial,” Ali says.
The first phase of the trial is being performed with healthy participants, rather than people with the disease, to establish safety and tolerability. The researchers can also look for the drug in blood samples, which could tell them whether it's reaching its target. Ali estimates that, if the company can establish safety and that it engages the right parts of the body, it will likely begin dosing patients with the disease in 2024.
Tenaya’s therapy delivers a healthy copy of the gene so that it makes a copy of the protein missing from the patients' hearts because of their mutation. The study will start with adult patients, then pivot potentially to children and even newborns, Ali says, “where there is an even greater unmet need because the disease progresses so fast that they have no options.”
Although this work still has a long way to go, Ali is excited about the potential because the gene therapy achieved positive results in the preclinical mouse trial. This animal trial demonstrated that the treatment reduced enlarged hearts, reversed electrophysiological abnormalities, and improved the functioning of the heart by increasing the ejection fraction after the single-dose of gene therapy. That measurement remained stable to the end of the animals’ lives, roughly 18 months, Ali says.
He’s also energized by the fact that heart disease has “taken a page out of the oncology playbook” by leveraging genetic research to develop more precise and targeted drugs and gene therapies.
“Now we are talking about a potential cure of a disease for which there was no cure and using a very novel concept,” says Melind Desai of the Cleveland Clinic.
Tenaya’s second program focuses on developing a gene therapy to mitigate the leading cause of hypertrophic cardiomyopathy through a specific gene called MYPBC3. The disease affects approximately 600,000 patients in the U.S. This particular genetic form, Ali explains, affects about 115,000 in the U.S. alone, so it is considered a rare disease.
“There are infants who are dying within the first weeks to months of life as a result of this mutation,” he says. “There are also adults who start having symptoms in their 20s, 30s and 40s with early morbidity and mortality.” Tenaya plans to apply before the end of this year to get the FDA’s approval to administer an investigational drug for this disease humans. If approved, the company will begin to dose patients in 2023.
“We now understand the genetics of the heart much better,” he says. “We now understand the leading genetic causes of hypertrophic myopathy, dilated cardiomyopathy and others, so that gives us the ability to take these large populations and stratify them rationally into subpopulations.”
Melind Desai, MD, who directs Cleveland Clinic’s Hypertrophic Cardiomyopathy Center, says that the goal of Tenaya’s second clinical study is to help improve the basic cardiac structure in patients with hypertrophic cardiomyopathy related to the MYPBC3 mutation.
“Now we are talking about a potential cure of a disease for which there was no cure and using a very novel concept,” he says. “So this is an exciting new frontier of therapeutic investigation for MYPBC3 gene-positive patients with a chance for a cure.
Neither of Tenaya’s two therapies address the gene mutation that has affected Borsari and her family. But Ali sees opportunity down the road to develop a gene therapy for her particular gene mutation, since it is the second leading cause of cardiomyopathy. Treating the MYH7 gene is especially challenging because it requires gene editing or silencing, instead of just replacing the gene.
Wendy Borsari was diagnosed at age 24 with a commonly inherited heart disease. She joined Tenaya as a patient advocate in 2021.
Wendy Borsari
“If you add a healthy gene it will produce healthy copies,” Ali explains, “but it won’t stop the bad effects of the mutant protein the gene produces. You can only do that by silencing the gene or editing it out, which is a different, more complicated approach.”
Euan Ashley, professor of medicine and genetics at Stanford University and founding director of its Center for Inherited Cardiovascular Disease, is confident that we will see genetic therapies for heart disease within the next decade.
“We are at this really exciting moment in time where we have diseases that have been under-recognized and undervalued now being attacked by multiple companies with really modern tools,” says Ashley, author of The Genome Odyssey. “Gene therapies are unusual in the sense that they can reverse the cause of the disease, so we have the enticing possibility of actually reversing or maybe even curing these diseases.”
Although no one is doing extensive research into a gene therapy for her particular mutation yet, Borsari remains hopeful, knowing that companies such as Tenaya are moving in that direction.
“I know that’s now on the horizon,” she says. “It’s not just some pipe dream, but will happen hopefully in my lifetime or my kids’ lifetime to help them.”