New Hope for Organ Transplantation: Life Without Anti-Rejection Drugs
Rob Waddell dreaded getting a kidney transplant. He suffers from a genetic condition called polycystic kidney disease that causes the uncontrolled growth of cysts that gradually choke off kidney function. The inherited defect has haunted his family for generations, killing his great grandmother, grandmother, and numerous cousins, aunts and uncles.
But he saw how difficult it was for his mother and sister, who also suffer from this condition, to live with the side effects of the drugs they needed to take to prevent organ rejection, which can cause diabetes, high blood pressure and cancer, and even kidney failure because of their toxicity. Many of his relatives followed the same course, says Waddell: "They were all on dialysis, then a transplant and ended up usually dying from cancers caused by the medications."
When the Louisville native and father of four hit 40, his kidneys barely functioned and the only alternative was either a transplant or the slow death of dialysis. But in 2009, when Waddell heard about an experimental procedure that could eliminate the need for taking antirejection drugs, he jumped at the chance to be their first patient. Devised by scientists at the University of Louisville and Northwestern University, the innovative approach entails mixing stem cells from the live kidney donor with that of the recipient to create a hybrid immune system, known as a chimera, that would trick the immune system and prevent it from attacking the implanted kidney.
The procedure itself was done at Northwestern Memorial Hospital in Chicago, using a live kidney donated by a neighbor of Waddell's, who camped out in Chicago during his recovery. Prior to surgery, Waddell underwent a conditioning treatment that consisted of low dose radiation and chemotherapy to weaken his own immune system and make room for the infusion of stem cells.
"The low intensity chemo and radiation conditioning regimen create just enough space for the donor stem cells to gain a foothold in the bone marrow and the donor's immune system takes over," says Dr. Joseph Levanthal, the transplant surgeon who performed the operation and director of kidney and pancreas transplantation at Northwestern University Feinberg School of Medicine. "That way the recipient develops an immune system that doesn't see the donor organ as foreign."
"As a surgeon, I saw what my patients had to go through—taking 25 pills a day, dying at an early age from heart disease, or having a 35% chance of dying every year on dialysis."
A week later, Waddell had the kidney transplant. The following day, he was infused with a complex cellular cocktail that included blood-forming stem cells derived from his donor's bone marrow mixed what are called tolerance inducing facilitator cells (FCs); these cells help the foreign stem cells get established in the recipient's bone marrow.
Over the course of the following year, he was slowly weaned off of antirejection medications—a precaution in case the procedure didn't work—and remarkably, hasn't needed them since. "I felt better than I had in decades because my kidneys [had been] degrading," recalls Waddell, now 54 and a CPA for a global beverage company. And what's even better is that this new approach offers hope for one of his sons who has also inherited the disorder.
Kidney transplants are the most frequent organ transplants in the world and more than 23,000 of these procedures were done in the United States in 2019, according to the United Network for Organ Sharing. Of this, about 7,000 operations are done annually using live organ donors; the remainder use organs from people who are deceased. Right now, this revolutionary new approach—as well as a similar strategy formulated by Stanford University scientists--is in the final phase of clinical trials. Ultimately, this research may pave the way towards realizing the holy grail of organ transplantation: preventing organ rejection by creating a tolerant state in which the recipient's immune system is compatible with the donor, which would eliminate the need for a lifetime of medications.
"As a surgeon, I saw what my patients had to go through—taking 25 pills a day, dying at an early age from heart disease, or having a 35% chance of dying every year on dialysis," says Dr. Suzanne Ildstad, a transplant surgeon and director of the Institute for Cellular Therapeutics at the University of Louisville, whose discovery of facilitator cells were the basis for this therapeutic platform. Ildstad, who has spent more than two decades searching for a better way, says, "This is something I have worked for my entire life."
The Louisville group uses a combination of chemo and radiation to replace the recipient's immune and blood forming cells with that of the donor. In contrast, the Stanford protocol involves harvesting the donor's blood stem cells and T-cells, which are the foot soldiers of the immune system that fight off infections and would normally orchestrate the rejection of the transplanted organ. Their transplant recipients undergo a milder form of "conditioning" that only radiates discrete parts of the body and selectively targets the recipient's T-cells, creating room for both sets of T-cells, a strategy these researchers believe has a better safety profile and less of a chance of rejection.
"We try to achieve immune tolerance by a true chimerism," says Dr. Samuel Strober, a professor of medicine for immunology and rheumatology at Stanford University and a leader of this research team. "The recipients immune system cells are maintained but mixed in the blood with that of the donor."
Studies suggest both approaches work. In a 2018 clinical trial conducted by Talaris Therapeutics, a Louisville-based biotech founded by Ildstad, 26 of 37 (70%) of the live donor kidney transplant recipients no longer need immunosuppressants. Last fall, Talaris began the final phase of clinical tests that will eventually encompass more than 120 such patients.
The Stanford group's cell-based immunotherapy, which is called MDR-101 and is sponsored by the South San Francisco biotech, Medeor Therapeutics, has had similar results in patients who received organs from live donors who were either well matched, such as one from siblings, meaning they were immunologically identical, or partially matched; Talaris uses unrelated donors where there is only a partial match.
In their 2020 clinical trial of 51 patients, 29 were fully matched and 22 were a partial match; 22 of the fully matched recipients didn't need antirejection drugs and ten of the partial matches were able to stop taking some of these medications without rejection. "With our fully matched, roughly 80% have been completely off drugs up to 14 years later," says Strober, "and reducing the number of drugs from three to one [in the partial matches] means you have far fewer side effects. The goal is to get them off of all drugs."
But these protocols are limited to a small number of patients—living donor kidney recipients. As a consequence, both teams are experimenting with ways to broaden their approach so they can use cadaver organs from deceased donors, with human tests planned in the coming year. Here's how that would work: after the other organs are removed from a deceased donor, stem cells are harvested from the donor's vertebrae in the spinal column and then frozen for storage.
"We do the transplant and give the patient a chance to recover and maintain them on drugs," says Ildstad. "Then we do the tolerance conditioning at a later stage."
If this strategy is successful, it would be a genuine game changer, and open the door to using these protocols for transplanting other cadaver organs, including the heart, lungs and liver. While the overall procedure is complex and costly, in the long run it's less expensive than repeated transplant surgeries, the cost of medications and hospitalizations for complications caused by the drugs, or thrice weekly dialysis treatments, says Ildstad.
And she adds, you can't put a price tag on the vast improvement in quality of life.
“Young Blood” Transfusions Are Not Ready For Primetime – Yet
The world of dementia research erupted into cheers when news of the first real victory in a clinical trial against Alzheimer's Disease in over a decade was revealed last October.
By connecting the circulatory systems of a young and an old mouse, the regenerative potential of the young mouse decreased, and the old mouse became healthier.
Alzheimer's treatments have been famously difficult to develop; 99 percent of the 200-plus such clinical trials since 2000 have utterly failed. Even the few slight successes have failed to produce what is called 'disease modifying' agents that really help people with the disease. This makes the success, by the midsize Spanish pharma company Grifols, worthy of special attention.
However, the specifics of the Grifols treatment, a process called plasmapheresis, are atypical for another reason - they did not give patients a small molecule or an elaborate gene therapy, but rather simply the most common component of normal human blood plasma, a protein called albumin. A large portion of the patients' normal plasma was removed, and then a sterile solution of albumin was infused back into them to keep their overall blood volume relatively constant.
So why does replacing Alzheimer's patients' plasma with albumin seem to help their brains? One theory is that the action is direct. Alzheimer's patients have low levels of serum albumin, which is needed to clear out the plaques of amyloid that slowly build up in the brain. Supplementing those patients with extra albumin boosts their ability to clear the plaques and improves brain health. However, there is also evidence suggesting that the problem may be something present in the plasma of the sick person and pulling their plasma out and replacing it with a filler, like an albumin solution, may be what creates the purported benefit.
This scientific question is the tip of an iceberg that goes far beyond Alzheimer's Disease and albumin, to a debate that has been waged on the pages of scientific journals about the secrets of using young, healthy blood to extend youth and health.
This debate started long before the Grifols data was released, in 2014 when a group of researchers at Stanford found that by connecting the circulatory systems of a young and an old mouse, the regenerative potential of the young mouse decreased, and the old mouse became healthier. There was something either present in young blood that allowed tissues to regenerate, or something present in old blood that prevented regeneration. Whatever the biological reason, the effects in the experiment were extraordinary, providing a startling boost in health in the older mouse.
After the initial findings, multiple research groups got to work trying to identify the "active factor" of regeneration (or the inhibitor of that regeneration). They soon uncovered a variety of compounds such as insulin-like growth factor 1 (IGF1), CCL11, and GDF11, but none seemed to provide all the answers researchers were hoping for, with a number of high-profile retractions based on unsound experimental practices, or inconclusive data.
Years of research later, the simplest conclusion is that the story of plasma regeneration is not simple - there isn't a switch in our blood we can flip to turn back our biological clocks. That said, these hypotheses are far from dead, and many researchers continue to explore the possibility of using the rejuvenating ability of youthful plasma to treat a variety of diseases of aging.
But the bold claims of improved vigor thanks to young blood are so far unsupported by clinical evidence.
The data remain intriguing because of the astounding results from the conjoined circulatory system experiments. The current surge in interest in studying the biology of aging is likely to produce a new crop of interesting results in the next few years. Both CCL11 and GDF11 are being researched as potential drug targets by two startups, Alkahest and Elevian, respectively.
Without clarity on a single active factor driving rejuvenation, it's tempting to try a simpler approach: taking actual blood plasma provided by young people and infusing it into elderly subjects. This is what at least one startup company, Ambrosia, is now offering in five commercial clinics across the U.S. -- for $8,000 a liter.
By using whole plasma, the idea is to sidestep our ignorance, reaping the benefits of young plasma transfusion without knowing exactly what the active factors are that make the treatment work in mice. This space has attracted both established players in the plasmapheresis field – Alkahest and Grifols have teamed up to test fractions of whole plasma in Alzheimer's and Parkinson's – but also direct-to-consumer operations like Ambrosia that just want to offer patients access to treatments without regulatory oversight.
But the bold claims of improved vigor thanks to young blood are so far unsupported by clinical evidence. We simply haven't performed trials to test whether dosing a mostly healthy person with plasma can slow down aging, at least not yet. There is some evidence that plasma replacement works in mice, yes, but those experiments are all done in very different systems than what a human receiving young plasma might experience. To date, I have not seen any plasma transfusion clinic doing young blood plasmapheresis propose a clinical trial that is anything more than a shallow advertisement for their procedures.
The efforts I have seen to perform prophylactic plasmapheresis will fail to impact societal health. Without clearly defined endpoints and proper clinical trials, we won't know whether the procedure really lowers the risk of disease or helps with conditions of aging. So even if their hypothesis is correct, the lack of strong evidence to fall back on means that the procedure will never spread beyond the fringe groups willing to take the risk. If their hypothesis is wrong, then people are paying a huge amount of money for false hope, just as they do, sadly, at the phony stem cell clinics that started popping up all through the 2000s when stem cell hype was at its peak.
Until then, prophylactic plasma transfusions will be the domain of the optimistic and the gullible.
The real progress in the field will be made slowly, using carefully defined products either directly isolated from blood or targeting a bloodborne factor, just as the serious pharma and biotech players are doing already.
The field will progress in stages, first creating and carefully testing treatments for well-defined diseases, and only then will it progress to large-scale clinical trials in relatively healthy people to look for the prevention of disease. Most of us will choose to wait for this second stage of trials before undergoing any new treatments. Until then, prophylactic plasma transfusions will be the domain of the optimistic and the gullible.
Who’s Responsible for Curbing the Teen Vaping Epidemic?
E-cigarettes are big business. In 2017, American consumers bought more than $250 million in vapes and juice-filled pods, and spent $1 billion in 2018. By 2023, the global market could be worth $44 billion a year.
"My nine-year-old actually knows what Juuling is. In many cases the [school] bathroom is now referred to as 'the Juuling room.'"
Investors are trying to capitalize on the phenomenal growth. In July 2018, Juul Labs, the company that owns 70 percent of the U.S. e-cigarette market share, raised $1.25 billion at a $16 billion valuation, then sold a 35 percent stake to Phillip Morris USA owner Altria Group in December. The second transaction valued the company at $38 billion. While the traditional tobacco market remains much larger, it's projected to grow at less than two percent a year, making the attractiveness of the rapidly expanding e-cigarette market obvious.
While Juul and other e-cigarette manufacturers argue that their products help adults quit smoking – and there's some research to back this narrative up – much of the growth has been driven by children and teenagers. One CDC study showed a 48 percent rise in e-cigarette use by middle schoolers and a 78 percent increase by high schoolers between 2017 and 2018, a jump from 1.5 million kids to 3.6 million. In response to the study, F.D.A. Commissioner Scott Gottlieb said, "We see clear signs that youth use of electronic cigarettes has reached an epidemic proportion."
Another study found that teenagers between 15 and 17 were 16 times more likely to use Juul than people aged 25-34. In December, Surgeon General Jerome Adams said, "My nine-year-old actually knows what Juuling is. In many cases the [school] bathroom is now referred to as 'the Juuling room.'"
And the product is seriously addictive. A single Juul pod contains as much nicotine as a pack of 20 regular cigarettes. Considering that 90 percent of smokers are addicted by 18 years old, it's clear that steps need to be taken to combat the growing epidemic.
But who should take the lead? Juul and other e-cigarette companies? The F.D.A. and other government regulators? Schools? Parents?
The Surgeon General's website has a list of earnest possible texts that parents can send to their teens to dissuade them from Juuling, like: "Hope none of your friends use e-cigarettes around you. Even breathing the cloud they exhale can expose you to nicotine and chemicals that can be dangerous to your health." While parents can attempt to police their teens, many experts believe that the primary push should come at a federal level.
The regulation battle has already begun. In September, the F.D.A. announced that Juul had 60 days to show a plan that would prevent youth from getting their hands on the product. The result was for the company to announce that it wouldn't sell flavored pods in retail stores except for tobacco, menthol, and mint; Juul also shuttered its Instagram and Facebook accounts. These regulations mirrored an F.D.A. mandate two days later that required flavored e-cigarettes to be sold in closed-off areas. "This policy will make sure the fruity flavors are no longer accessible to kids in retail sites, plan and simple," Commissioner Gottlieb said when announcing the moves. "That's where they're getting access to the e-cigs and we intend to end those sales."
"There isn't a great history of the tobacco industry acting responsibly and being able to in any way police itself."
While so far, Gottlieb – who drew concerns about conflict of interest due to his past position as a board member at e-cigarette company, Kure – has pleased anti-smoking advocates with his efforts, some observers also argue that it needs to go further. "Overall, we didn't know what to expect when a new commissioner came in, but it's been quite refreshing how much attention has been paid to the tobacco industry by the F.D.A.," Robin Koval, CEO and president of Truth Initiative, said a day after the F.D.A. announced the proposed regulations. "It's important to have a start. I certainly want to give credit for that. But we were really hoping and feel that what was announced...doesn't go far enough."
The issue is the industry's inability or unwillingness to police itself in the past. Juul, however, claims that it's now proactively working to prevent young people from taking up its product. "Juul Labs and F.D.A. share a common goal – preventing youth from initiating on nicotine," a company representative said in an email. "To paraphrase Commissioner Gottlieb, we want to be the off-ramp for adult smokers to switch from cigarettes, not an on-ramp for America's youth to initiate on nicotine. We won't be successful in our mission to serve adult smokers if we don't narrow the on-ramp... Our intent was never to have youth use Juul products. But intent is not enough, the numbers are what matter, and the numbers tell us underage use of e-cigarette products is a problem. We must solve it."
Juul argues that its products help adults quit – even offering a calculator on the website showing how much people will save – and that it didn't target youth. But studies show otherwise. Furthermore, the youth smoking prevention curriculum the company released was poorly received. "It's what Philip Morris did years ago," said Bonnie Halpern-Felsher, a professor of pediatrics at Stanford who helped author a study on the program's faults. "They aren't talking about their named product. They are talking about vapes or e-cigarettes. Youth don't consider Juuls to be vapes or e-cigarettes. [Teens] don't talk about flavors. They don't talk about marketing. They did it to look good. But if you look at what [Juul] put together, it's a pretty awful curriculum that was put together pretty quickly."
The American Lung Association gave the FDA an "F" for failing to take mint and menthol e-cigs off the market, since those flavors remain popular with teens.
Add this all up, and in the end, it's hard to see the industry being able to police itself, critics say. Neither the past examples of other tobacco companies nor the present self-imposed regulations indicate that this will succeed.
"There isn't a great history of the tobacco industry acting responsibly and being able to in any way police itself," Koval said. "That job is best left to the F.D.A., and to the states and localities in what they can regulate and legislate to protect young people."
Halpern-Felsher agreed. "I think we need independent bodies. I really don't think that a voluntary ban or a regulation on the part of the industry is a good idea, nor do I think it will work," she said. "It's pretty much the same story, of repeating itself."
Just last week, the American Association of Pediatrics issued a new policy statement calling for the F.D.A. to immediately ban the sale of e-cigarettes to anyone under age 21 and to prohibit the online sale of vaping products and solutions, among other measures. And in its annual report, the American Lung Association gave the F.D.A. an "F" for failing to take mint and menthol e-cigs off the market, since those flavors remain popular with teens.
Few, if any people involved, want more regulation from the federal government. In an ideal world, this wouldn't be necessary. But many experts agree that it is. Anything else is just blowing smoke.