Is There a Blind Spot in the Oversight of Human Subject Research?
Human experimentation has come a long way since congressional hearings in the 1970s exposed patterns of abuse. Where yesterday's patients were protected only by the good conscience of physician-researchers, today's patients are spirited past hazards through an elaborate system of oversight and informed consent. Yet in many ways, the project of grounding human research on ethical foundations remains incomplete.
As human research has become a mainstay of career and commercial advancement among academics, research centers, and industry, new threats to research integrity have emerged.
To be sure, much of the medical research we do meets exceedingly high standards. Progress in cancer immunotherapy, or infectious disease, reflects the best of what can be accomplished when medical scientists and patients collaborate productively. And abuses of the earlier part of the 20th century--like those perpetrated by the U.S. Public Health Service in Guatemala--are for the history books.
Yet as human research has become a mainstay of career and commercial advancement among academics, research centers, and industry, new threats to research integrity have emerged. Many flourish in the blind spot of current oversight systems.
Take, for example, the tendency to publish only "positive" findings ("publication bias"). When patients participate in studies, they are told that their contributions will promote medical discovery. That can't happen if results of experiments never get beyond the hard drives of researchers. While researchers are often eager to publish trials showing a drug works, according to a study my own team conducted, fewer than 4 in 10 trials of drugs that never receive FDA approval get published. This tendency- which occurs in academia as well as industry- deprives other scientists of opportunities to build on these failures and make good on the sacrifice of patients. It also means the trials may be inadvertently repeated by other researchers, subjecting more patients to risks.
On the other hand, many clinical trials test treatments that have already been proven effective beyond a shadow of doubt. Consider the drug aprotinin, used for the management of bleeding during surgery. An analysis in 2005 showed that, not long after the drug was proven effective, researchers launched dozens of additional placebo-controlled trials. These redundant trials are far in excess of what regulators required for drug approval, and deprived patients in placebo arms of a proven effective therapy. Whether because of an oversight or deliberately (does it matter?), researchers conducting these trials often failed in publications to describe previous evidence of efficacy. What's the point of running a trial if no one reads the results?
It is surprisingly easy for companies to hijack research to market their treatments.
At the other extreme are trials that are little more than shots in the dark. In one case, patients with spinal cord injury were enrolled in a safety trial testing a cell-based regenerative medicine treatment. After the trial stopped (results were negative), laboratory scientists revealed that the cells had been shown ineffective in animal experiments. Though this information had been available to the company and FDA, researchers pursued the trial anyway.
It is surprisingly easy for companies to hijack research to market their treatments. One way this happens is through "seeding trials"- studies that are designed not to address a research question, but instead to habituate doctors to using a new drug and to generate publications that serve as advertisements. Such trials flood the medical literature with findings that are unreliable because studies are small and not well designed. They also use the prestige of science to pursue goals that are purely commercial. Yet because they harm science- not patients (many such studies are minimally risky because all patients receive proven effective medications)- ethics committees rarely block them.
Closely related is the phenomenon of small uninformative trials. After drugs get approved by the FDA, companies often launch dozens of small trials in new diseases other than the one the drug was approved to treat. Because these studies are small, they often overestimate efficacy. Indeed, the way trials are often set up, if a company tests an ineffective drug in 40 different studies, one will typically produce a false positive by chance alone. Because companies are free to run as many trials as they like and to circulate "positive" results, they have incentives to run lots of small trials that don't provide a definitive test of their drug's efficacy.
Universities, funding bodies, and companies should be scored by a neutral third-party based on the impact of their trials -- like Moody's for credit ratings.
Don't think public agencies are much better. Funders like the National Institutes of Health secure their appropriations by gratifying Congress. This means that NIH gets more by spreading its funding among small studies in different Congressional districts than by concentrating budgets among a few research institutions pursuing large trials. The result is that some NIH-funded clinical trials are not especially equipped to inform medical practice.
It's tempting to think that FDA, medical journals, ethics committees, and funding agencies can fix these problems. However, these practices continue in part because FDA, ethics committees, and researchers often do not see what is at stake for patients by acquiescing to low scientific standards. This behavior dishonors the patients who volunteer for research, and also threatens the welfare of downstream patients, whose care will be determined by the output of research.
To fix this, deficiencies in study design and reporting need to be rendered visible. Universities, funding bodies, and companies should be scored by a neutral third-party based on the impact of their trials, or the extent to which their trials are published in full -- like Moody's for credit ratings, or the Kelley Blue Book for cars. This system of accountability would allow everyone to see which institutions make the most of the contributions of research subjects. It could also harness the competitive instincts of institutions to improve research quality.
Another step would be for researchers to level with patients when they enroll in studies. Patients who agree to research are usually offered bromides about how their participation may help future patients. However, not all studies are created equal with respect to merit. Patients have a right to know when they are entering studies that are unlikely to have a meaningful impact on medicine.
Ethics committees and drug regulators have done a good job protecting research volunteers from unchecked scientific ambition. However, today's research is plagued by studies that have poor scientific credentials. Such studies free-ride on the well-earned reputation of serious medical science. They also potentially distort the evidence available to physicians and healthcare systems. Regulators, academic medical centers, and others should establish policies that better protect human research volunteers by protecting the quality of the research itself.
Catching colds may help protect kids from Covid
A common cold virus causes the immune system to produce T cells that also provide protection against SARS-CoV-2, according to new research. The study, published last month in PNAS, shows that this effect is most pronounced in young children. The finding may help explain why most young people who have been exposed to the cold-causing coronavirus have not developed serious cases of COVID-19.
One curiosity stood out in the early days of the COVID-19 pandemic – why were so few kids getting sick. Generally young children and the elderly are the most vulnerable to disease outbreaks, particularly viral infections, either because their immune systems are not fully developed or they are starting to fail.
But solid information on the new infection was so scarce that many public health officials acted on the precautionary principle, assumed a worst-case scenario, and applied the broadest, most restrictive policies to all people to try to contain the coronavirus SARS-CoV-2.
One early thought was that lockdowns worked and kids (ages 6 months to 17 years) simply were not being exposed to the virus. So it was a shock when data started to come in showing that well over half of them carried antibodies to the virus, indicating exposure without getting sick. That trend grew over time and the latest tracking data from the CDC shows that 96.3 percent of kids in the U.S. now carry those antibodies.
Antibodies are relatively quick and easy to measure, but some scientists are exploring whether the reactions of T cells could serve as a more useful measure of immune protection.
But that couldn't be the whole story because antibody protection fades, sometimes as early as a month after exposure and usually within a year. Additionally, SARS-CoV-2 has been spewing out waves of different variants that were more resistant to antibodies generated by their predecessors. The resistance was so significant that over time the FDA withdrew its emergency use authorization for a handful of monoclonal antibodies with earlier approval to treat the infection because they no longer worked.
Antibodies got most of the attention early on because they are part of the first line response of the immune system. Antibodies can bind to viruses and neutralize them, preventing infection. They are relatively quick and easy to measure and even manufacture, but as SARS-CoV-2 showed us, often viruses can quickly evolve to become more resistant to them. Some scientists are exploring whether the reactions of T cells could serve as a more useful measure of immune protection.
Kids, colds and T cells
T cells are part of the immune system that deals with cells once they have become infected. But working with T cells is much more difficult, takes longer, and is more expensive than working with antibodies. So studies often lags behind on this part of the immune system.
A group of researchers led by Annika Karlsson at the Karolinska Institute in Sweden focuses on T cells targeting virus-infected cells and, unsurprisingly, saw that they can play a role in SARS-CoV-2 infection. Other labs have shown that vaccination and natural exposure to the virus generates different patterns of T cell responses.
The Swedes also looked at another member of the coronavirus family, OC43, which circulates widely and is one of several causes of the common cold. The molecular structure of OC43 is similar to its more deadly cousin SARS-CoV-2. Sometimes a T cell response to one virus can produce a cross-reactive response to a similar protein structure in another virus, meaning that T cells will identify and respond to the two viruses in much the same way. Karlsson looked to see if T cells for OC43 from a wide age range of patients were cross-reactive to SARS-CoV-2.
And that is what they found, as reported in the PNAS study last month; there was cross-reactive activity, but it depended on a person’s age. A subset of a certain type of T cells, called mCD4+,, that recognized various protein parts of the cold-causing virus, OC43, expressed on the surface of an infected cell – also recognized those same protein parts from SARS-CoV-2. The T cell response was lower than that generated by natural exposure to SARS-CoV-2, but it was functional and thus could help limit the severity of COVID-19.
“One of the most politicized aspects of our pandemic response was not accepting that children are so much less at risk for severe disease with COVID-19,” because usually young children are among the most vulnerable to pathogens, says Monica Gandhi, professor of medicine at the University of California San Francisco.
“The cross-reactivity peaked at age six when more than half the people tested have a cross-reactive immune response,” says Karlsson, though their sample is too small to say if this finding applies more broadly across the population. The vast majority of children as young as two years had OC43-specific mCD4+ T cell responses. In adulthood, the functionality of both the OC43-specific and the cross-reactive T cells wane significantly, especially with advanced age.
“Considering that the mortality rate in children is the lowest from ages five to nine, and higher in younger children, our results imply that cross-reactive mCD4+ T cells may have a role in the control of SARS-CoV-2 infection in children,” the authors wrote in their paper.
“One of the most politicized aspects of our pandemic response was not accepting that children are so much less at risk for severe disease with COVID-19,” because usually young children are among the most vulnerable to pathogens, says Monica Gandhi, professor of medicine at the University of California San Francisco and author of the book, Endemic: A Post-Pandemic Playbook, to be released by the Mayo Clinic Press this summer. The immune response of kids to SARS-CoV-2 stood our expectations on their head. “We just haven't seen this before, so knowing the mechanism of protection is really important.”
Why the T cell immune response can fade with age is largely unknown. With some viruses such as measles, a single vaccination or infection generates life-long protection. But respiratory tract infections, like SARS-CoV-2, cause a localized infection - specific to certain organs - and that response tends to be shorter lived than systemic infections that affect the entire body. Karlsson suspects the elderly might be exposed to these localized types of viruses less often. Also, frequent continued exposure to a virus that results in reactivation of the memory T cell pool might eventually result in “a kind of immunosenescence or immune exhaustion that is associated with aging,” Karlsson says. https://leaps.org/scientists-just-started-testing-a-new-class-of-drugs-to-slow-and-even-reverse-aging/particle-3 This fading protection is why older people need to be repeatedly vaccinated against SARS-CoV-2.
Policy implications
Following the numbers on COVID-19 infections and severity over the last three years have shown us that healthy young people without risk factors are not likely to develop serious disease. This latest study points to a mechanism that helps explain why. But the inertia of existing policies remains. How should we adjust policy recommendations based on what we know today?
The World Health Organization (WHO) updated their COVID-19 vaccination guidance on March 28. It calls for a focus on vaccinating and boosting those at risk for developing serious disease. The guidance basically shrugged its shoulders when it came to healthy children and young adults receiving vaccinations and boosters against COVID-19. It said the priority should be to administer the “traditional essential vaccines for children,” such as those that protect against measles, rubella, and mumps.
“As an immunologist and a mother, I think that catching a cold or two when you are a kid and otherwise healthy is not that bad for you. Children have a much lower risk of becoming severely ill with SARS-CoV-2,” says Karlsson. She has followed public health guidance in Sweden, which means that her young children have not been vaccinated, but being older, she has received the vaccine and boosters. Gandhi and her children have been vaccinated, but they do not plan on additional boosters.
The WHO got it right in “concentrating on what matters,” which is getting traditional childhood immunizations back on track after their dramatic decline over the last three years, says Gandhi. Nor is there a need for masking in schools, according to a study from the Catalonia region of Spain. It found “no difference in masking and spread in schools,” particularly since tracking data indicate that nearly all young people have been exposed to SARS-CoV-2.
Both researchers lament that public discussion has overemphasized the quickly fading antibody part of the immune response to SARS-CoV-2 compared with the more durable T cell component. They say developing an efficient measure of T cell response for doctors to use in the clinic would help to monitor immunity in people at risk for severe cases of COVID-19 compared with the current method of toting up potential risk factors.
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 new scientific theories and progress to give you a therapeutic dose of inspiration headed into the weekend.
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Here are the stories covered this week:
- The eyes are the windows to the soul - and biological aging?
- What bean genes mean for health and the planet
- This breathing practice could lower levels of tau proteins
- AI beats humans at assessing heart health
- Should you get a nature prescription?