I post market design related news and items about repugnant markets. See my Stanford profile. I have a 2026 book : Moral Economics The subtitle is "From Prostitution to Organ Sales, What Controversial Transactions Reveal About How Markets Work."
Showing posts with label kidney exchange. Show all posts
Showing posts with label kidney exchange. Show all posts
"Editor’s note: Entertainer Pat Boone, Pro Football Hall of Fame quarterback Steve Young and actor Robert Hays of “Airplane” fame signed on as authors of a guest essay provided by US Blood Donors.org for Mississippi Today on “Kidney Chains.”
"This guest essay, though, written from a national perspective is of special importance to MT Ideas since Mississippi is among the states with the highest number of kidney disease-related deaths per 100,000 adjusted for age, according to the National Center for Health Statistics.*
"Hundreds of thousands of dialysis patients in the United States could receive lifesaving kidney transplants sooner if one simple idea became widely known: “kidney chains”— sequences of living-donor transplants that allow one donor to save multiple lives.
The goal is simple: Make “kidney chains” a household phrase.
Kidney chains allow living donors who are incompatible with their intended recipient to help initiate a sequence of transplants that can save multiple lives. The concept builds on Nobel Prize-recognized work** in market design and has already enabled thousands of lifesaving kidney transplants.
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*Figure from the NCHS
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** The video link is to the last three minutes of this 15 minute talk from 2014
Below is a Youtube video of all the talks given at the 4th International Workshop on Game Theory and Economic Applications at the University of São Paulo last Wednesday.
My talk, whose title was "Controversial markets, black markets, and market design" is introduced at minute 2:24 (and for some of you the link below should start up there). The talk before mine is by Bob Wilson, and the one after by Paul Milgrom, but the video camera was on all the time, so you have to scroll to get to the actual talks.)
My talk begins with some general discussion of how market design and engineering economics are related to game theory. Then I introduce kidney exchange as the talk's main example, and discuss some of the accompanying controversies, including those currently being encountered in Brazil.
One feature of giving talks to unfamiliar audiences is that you only get noisy feedback on how your talk was received. This past June, I gave the Starzl Lecture at the American Transplant Congress in Boston. (The ATC is jointly organized by the two big American transplant societies, the AST and the ASTS,*) I spoke to an audience of about 1500 people (just a guess, but I could see some empty seats in an auditorium set up for 2,000). My talk included topics, including global kidney exchange, that have raised controversies.
Afterwards, what seemed like a lot of people came to speak to me, and were enthusiastic about my talk. But "a lot of people" was fewer than 100. So what about everyone else? (It probably wouldn't be statistically kosher to assume that those who came to congratulate me were a representative sample:)
Since global kidney exchange has led to some people calling me an organ trafficker, I didn't have any measure of the general sentiment of the meeting.
I got some reassuring news recently when the ATC sent out an email soliciting ideas for talks for next year's meeting, in Seattle. The email came with a picture from this oat meeting:
So I'm guessing this means that my talk was well received by people responsible for organizing the next meeting.
And, indeed, I'm getting multiple signals that there's an appetite for productive change in the transplant community. I hope to have more to say about that in the coming year.
For the first time in Brazil, two transplant centers in different cities carried out a paired kidney donation — swapping incompatible living donors so each recipient gets a compatible kidney from someone else's donor instead. The initiative was led by Hospital das Clínicas at USP's medical school (HCFMUSP) in São Paulo and Santa Casa de Juiz de Fora in Minas Gerais.
The surgeries happened simultaneously at both hospitals — a donor from São Paulo traveled to Juiz de Fora to donate to the Minas Gerais recipient, while the donor from Minas Gerais went to Hospital das Clínicas in São Paulo to donate to the São Paulo patient.
the two hospitals use an internationally developed (U.S.-built) platform that cross-references immunological traits, body size, and donor kidney quality to identify the best-matching combinations — this is functionally the same kind of algorithm we've been discussing with NKR.
Brazil has no specific regulation for paired kidney donation under its National Transplant System, so the procedure currently proceeds only as research.
Here's a video in which Mike Rees, the founder of the Alliance for Paired Kidney Donation (APKD)
describes how (with the help of a grant from Stanford Impact Labs) the
APKD is helping Brazilian transplant docs get kidney exchange going
there.
Here's an editorial arguing that as the recently legalized kidney exchange in Germany is implemented, attention should be paid to the controversies that have been encountered and addressed elsewhere, including those about non-directed donors, and the governance and transparency of transplant decisions.
"In 1986 F.T. Rapaport outlined a core idea behind kidney paired exchange: that a registry can coordinate incompatible donor-recipient pairs so that incompatibility becomes a solvable matching problem rather than a barrier to transplantation1. Today, forty years later, Germany is on the verge of making that coordination legally possible. In October 2025, the German federal cabinet approved a draft amendment to the Transplantation Act that would enable kidney paired exchange and non-directed anonymous living kidney donation, while strengthening donor protection and establishing the legal basis for a national program with a central matching function. If operationalized, Germany would move from a restrictive framework for living kidney donation, historically tied to a strict requirement of a close relationship between donor and recipient, toward a governance model that supports kidney exchange and donor chains at scale.
"This moment is internationally relevant because Germany now faces the same policy questions that have shaped kidney paired exchange implementation elsewhere. The impending change creates an opportunity to learn from other countries on key issues, including who should govern a registry, which safeguards ensure legitimacy, how to balance privacy and transparency regarding organ quality, and how to promote access without risking commercialization. Rather than being mere technical considerations, these questions are constitutive for the legitimacy and public trust required for kidney paired exchange to function as a public good.
"Early debates about living kidney donation repeatedly straddled suspicion and admiration. In the 1970s, living non-related and particularly non-directed donors were sometimes portrayed in medical discourse as psychologically unstable or even pathological, raising concerns about whether such donors should be permitted to proceed2,3.
...
" History offers two more lessons: (i) Donor protection and respecting donor agency are not mutually exclusive: psychosocial assessment, independent counseling, and rigorous consent procedures can reduce coercion and misunderstanding while still recognizing donors as autonomous agents making a deliberate moral choice. (ii) Public legitimacy is fragile and easily lost: If suspicion dominates, programs risk being viewed as illegitimate or unfair. If, on the other hand, enthusiasm and implementation moves faster than safeguards, programs risk scandal, backlash and, ultimately, lose public support. Germany’s 2012 transplant scandal, involving the manipulation of patient data to improve waiting-list positions, offers a cautionary example of how deficits in transparency and accountability can erode trust in transplantation more broadly and disrupt an entire program4."
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There are many reviews of the international experience. Below is a recent one from physicians at Erasmus University in the Netherlands:
"Living donor kidney transplantation (LDKT) offers superior graft survival and cost-effectiveness compared with deceased donor transplantation (DDKT), yet the availability of immunologically compatible living donors limits its reach. Kidney exchange programs (KEPs) can overcome these barriers by matching incompatible pairs through paired exchanges, domino chains, and nonsimultaneous extended altruistic donor (NEAD) chains. This review summarizes the evolution and current landscape of national and international KEPs. We examine operational challenges (cold ischemia time [CIT], logistical coordination, algorithmic fairness, and ethical and regulatory heterogeneity) and explore innovations in matching algorithms, international kidney exchange debates, and machine perfusion technologies. We conclude by proposing strategic priorities to optimize capacity, equity, and outcomes in future kidney exchange efforts. "
A recent letter from Mayo Clinic transplant providers raises concerns related to bad outcomes when some patient-donor pairs are separated (the donor donates before the intended recipient is matched to a donor), but the intended recipient is hard to match.
"it is important to recognize that some KPD organizations, such as the National Kidney Registry, operate as private organizations (POs) with distinct governance structures, priorities, and commercial interests. These objectives may not always fully align with those of transplant centers or the broader transplant community, potentially creating gaps in transparency and accountability within a process that directly affects donors and recipients.
"We recently encountered a concerning example that illustrates the ethical tensions inherent when donor mentors are employed by private KPD organizations. ... During a routine text message check-in, the mentor initiated a discussion promoting voucher donation, emphasizing that voucher donors receive priority within the system.
... "The donor described the interaction as uncomfortable and “pushy,” and subsequently contacted our transplant center for guidance. Notably, the communication focused on system-level benefits and prioritization metrics but did not explore critical clinical and ethical considerations specific to this donor-recipient pair.
"The discussion was insufficiently individualized and appeared framed toward a preferred outcome. The donor’s preferences and the potential downsides of voucher donation were not explored. The mentor did not ask how the donor would feel if they proceeded with voucher donation and their intended recipient never received a transplant. The discussion lacked any reference to recipient factors that could influence the advisability of voucher donation, including sensitization or recipient comorbid conditions. There was also no discussion about why KPD was being used. Often the donor can donate directly to a recipient (eg, compatible pair), but may decide to enter a KPD pool temporarily to see whether the recipient could receive a transplant with improved size or HLA matching. Finally, the average wait times for a recipient to receive a transplant after voucher donation were not mentioned.
"This interaction raises concern about whether the mentor’s guidance was fully centered on the donor-recipient pair or instead influenced, even indirectly, by organizational incentives to increase voucher participation. When donor mentors are employed by entities that operationally benefit from particular forms of donation, even well-intentioned communication can create perceived or actual conflicts of interest. Transparency regarding these structural incentives, along with a clear commitment to individualized donor-centered mentoring, is essential to maintaining ethical integrity in these situations.
...
"As stewards of living donor trust, the transplant community must ensure that innovation proceeds with appropriate oversight. Any perception that donor education or support is influenced by business interests risks eroding public confidence in living donation programs, with potentially far-reaching consequences that could discourage future donors."
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Here's an article on NKR from the NYT that discusses its particular voucher program (and also its finances):
"One of N.K.R.’s most innovative policies, many doctors said, is known as voucher donation: Donors can choose to give their kidneys immediately, in exchange for organ vouchers their loved ones redeem later.
"This arrangement has helped N.K.R. expand its pool. But vouchers add risk for donors giving on behalf of hard-to-match patients. They might go through surgery months or even years before their loved ones get a match. Matches are especially unlikely, doctors said, for “very highly sensitized” patients who carry antibodies likely to reject a transplant.
...
" many doctors said that given N.K.R.’s relatively small size, these rare patients would be better served waiting for a match before their loved ones donate.
"“We definitely recommend that they not go with a voucher,” said Dr. Miklos Molnar, the medical director of the kidney transplantation program at the University of Utah, which works with N.K.R.
"Dozens of highly sensitized patients who are also on kidney dialysis have waited a year or more after their loved ones donated, according to N.K.R. quarterly reports since 2022. At least three waited more than four years, and one for seven years.
"Doctors told The Times that they knew of some patients who became too sick or died before they redeemed their vouchers."
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Here's a a discussion of the earliest exploration of unpaired donation that I know of:
"Speaker A: You have a pretty long chapter on same sex marriage in the book where you go through the sort of legislative history both in various states and the country. And after, like reading so much of the history of this, I would say, like, this is so Slate, I’m going to just come out and say that 95% plus of our listeners are perfectly fine with same sex marriage. It seems perfectly normal to us. It’s kind of hard for us to imagine why it was that we ever had a problem with it in the first place. But you went back, you Were looking at a bunch of contemporaneous literature. Do you have a sympathy for the anti side of the debate? Do you see where they were coming from?
Speaker B: Well, I think I see where they were coming from. I can do that without having necessarily a lot of sympathy for them. But they were tooled up quite early on. So for a long time in the United States, there were laws against sex that sometimes had the names unnatural acts in them. And in California, and I’m going to fudge the dates now, but sometime in the 1970s, long before there was any same sex marriage, they decided that laws against same sex sex violated the equal rights provisions of the California constitution. And so they changed them. They made those laws unconstitutional. And almost immediately after, like two years after, in the 1970s, the California legislature passed a law against same sex marriage. That is, the people who were looking into the far future and thinking that they really hated same sex marriage had felt protected by the laws against consensual sex between adults of, you know, say, sodomy. And all of a sudden they felt unprotected. So long before any same sex marriage became legal in the United States, there started to be laws against it.
Speaker A: That’s kind of wild. You’re just, you’re sort of like cutting it off at the past. It’s not legal anywhere. No one’s even trying to make it legal. We’re going to make it illegal just in case. And we saw that at the federal level as well.
Speaker B: Absolutely. When the state of Massachusetts finally, when its courts finally legalized same sex marriage in Massachusetts, the federal government passed a law called the defense of marriage act, which was intended to defend marriage against same sex marriage. So that’s a really unusual state of affairs. And again, when I say that’s a repugnant transaction, One of the things I emphasize in the book is I don’t mean that I disapprove of it or that you should, but that some people do. And the long political fight makes it clear that the people who objected to it objected very strongly.
Speaker A: I mean, I was around for a lot of these court cases and legislative moves, but even at the time, I didn’t entirely understand where the opponents were coming from. So is it mostly like a biblical thing?
Speaker B: So I think it’s partly a religious thing and some of that is biblical. There were some passages in Hebrew Bible even that could be interpreted as disapproving of same sex relations. And when you look back at the long history of humanity, there were lots of taboos about sex. And I think one way to think of them is, for most of human history, sex between a man and a woman often resulted in pregnancy, and pregnancy often resulted in a live birth in a baby. And society has and had some interest in making sure that babies were taken care of. And one way to do that is to say babies should be born into families, and therefore before people have sex, they should be married to each other. And so there are a whole set of taboos that might be thought of as society’s way of trying to take care of babies. But of course, technology changes. And contraception, reliable contraception, means that it’s possible to have sex without too much risk of a baby. In vitro fertilization, IVF means that it’s possible to have babies without sex. So all of a sudden, some of those barriers that may have seem essential to the orderly running of society didn’t seem so essential. And I think that opened up room for us to think more about who could have sex with whom and who could form a family with whom.
The moral philosophers Peter Singer & Kasia de Lazari Radek interviewed me about Moral Economics on their podcast Lives Well Lived. At the end, they ask their guests to think about their own life, and to what extent their own life has been well lived. That's a bit like being asked what you would like to have inscribed on your tombstone. So I hedged a bit. But the conversation that followed was interesting, so if you scroll down you'll see the transcript of that last bit, which starts about minute 1:09 in the recording.
Jun 25, 2026 "Nobel Prize-winning economist Alvin Roth explains how innovative market designs can reduce exploitation and save lives. Drawing on his pioneering work in kidney exchanges, Roth explores some of society’s most contentious moral dilemmas involving organ markets, surrogacy, and unpacks the ethical tensions surrounding what he calls “repugnant transactions.”
"Lives Well Lived is hosted by Peter Singer & Kasia de Lazari Radek. Episodes consist of interviews with remarkable guests who have lived well, both in the sense of living an ethical life, but also in that they are fulfilled and happy with what they have achieved in their lives. Some of these guests will be well-known figures, but others who are doing extraordinary things will be unfamiliar to almost all of our listeners. The conversations will often cover ground that involves ethics, how to live well, and how to make a positive difference in the world. It will inspire and empower its audience to change their own lives for the better. "
Here's the transcript of the last few minutes of the conversation (starting around minute 1:09 of the recording).
PETER: We always asked our guests to think about their own life, and to what extent their own life has been well lived, and by what criteria they make that judgment? Would you like to comment on that, Al?
Al: Sure. Has my life been well lived so far? Well, first, I've had a very fortunate life so far. I am lucky in my family, and my children, and my grandchildren, and my friends. And when you talk about friends, one thing that's often not talked about are the relations that professors have with students. So I've made lifelong friendships with many students who are productively engaged around the world, and that's very gratifying, and I hope it helps make my life worthwhile.
But also, I'm a market designer, and market design is very outward facing part of, economics. And, one of its goals is, a phrase even older than effective altruism, which is tikkun olam (תִּיקּוּן עוֹלָם) mending the world. And one of the things that market designers try to do is fix markets when they're broken or create them when they're absent. When you think of something like kidney exchange, you know, in a different podcast, on a different subject, I could tell you about victory after victory, where thousands, many thousands of transplants have been done, and lives have been saved through kidney exchange, even though it's in a war that we're losing: the shortage of kidneys is growing faster than the increase in transplants as diabetes grows, and high blood pressure, things like that. So, I would hope that some of my life has looked well lived, not just from the inside, but perhaps also from the outside.
Peter: Absolutely sure that it has. You're right. And what you've done for kidney markets is just one example, where you've saved many lives, and I think that obviously would be an important part of living well. despite the fact that the problem, as you say, has not been solved as a whole.
Kasia: It must be very satisfying.
Al: People often say that to me, and it will be satisfying when I'm retired. Right now, it's still frustrating, right? There's so much left to do, and it's not so easy to do it. But the times are changing. In two weeks, I'm gonna be opening up the American Transplant Conference in Boston, and, you know, there are people who invite me to these things. I sometimes joke with my young colleagues that as the old people who feel a lot of repugnance die off, it'll be left to just us young people. And we'll see.
I was in a transplant conference in Cairo in November. in which we tried to reach consensus on the question of, should countries have to be self sufficient in transplantation, which is the traditional position of the World Health Organization and some other organizations. And, of course, it works against countries that don't have much kidney exchange, because you need a big pool of patient-donor pairs to find lots of exchanges. And in that spirit, incidentally, during COVID, I was in the United Arab Emirates for the first kidney exchange between the UAE and Israel. And, that had to overcome a lot of obstacles, but it makes a lot of sense, because the UAE and Israel each have only a population of about 10 million. And that's not enough to find kidneys in your domestic pool for the hard to match patients, for patients who have a lot of antibodies to human proteins. So, we would like to see much more cooperation and not just between rich countries, but also inviting patients from poor countries, patient-donor pairs, to take part in American kidney exchange. And that's something that remains very controversial, but I think that we might be on the verge of making some progress with that. That's something that Peter has written about also.
Peter: Yes, I certainly hope so, and because I'm now working as a regular visiting professor in Singapore, which is another small country, the population of about 6 million, there's a very good case for saying that Singapore should also get into international kidney exchanges, and perhaps assist some of the poorer countries in its region. So we're trying to make that argument, and let's hope we succeed. One thing I've tell you, there might be bad news. I don't believe that when you retire from Stanford, you're going to stop working on these issues and be able to relax and feel satisfied, because I know I retired from Princeton 2 years ago, but the issues that I'm concerned about, whether it's the factory farming or global poverty, or all these kidney issues as well, I'm still concerned about, I can't let them go just because I'm no longer paid to be a professor at Princeton.
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In terms of lives lived well and deeply, here's an earlier post of mine about teachers and students.
Here's a new report from Italy on initiating kidney exchange chains with a deceased donor.* In Italy to date, 34 deceased donor initiated chains generated 84 transplants (34 from deceased donors and 50 from living donors), including 56 among incompatible pairs and 28 to candidates on the waitlist.
"Integrating deceased and living donation through deceased-donor (DD)-initiated chains can expand kidney transplant access in small paired exchange pools. The Italian DEC-K program allocates a DD kidney to initiate a chain (chain-initiating kidney, CIK) among incompatible living-donor (LD) pairs, ultimately returning a LD kidney to the national waiting list (WL). We report the first long-term national results of this donor organ allocation model.
"Methods: All DEC-K chains performed in Italy (2018-2025) were retrospectively analyzed. Recipients were stratified by kidney source (CIK vs LD).
... "Results: Thirty-four DEC-K chains generated 84 transplants (34 DD and 50 LD), including 56 among incompatible pairs and 28 to candidates on the WL. Donor withdrawal occurred once. Four chains were terminated early after CIK transplantation due to newly developed contraindications to donation. At a median follow-up of 60 months, 1- and 3-year graft survival was 100% in both groups, while patient survival was 97.1% for CIK and 98.0% for LD. Three CIK and one LD recipients died with functioning graft (suicide, sepsis, urothelial carcinoma, and acute myocardial infarction, respectively). One CIK recipient experienced graft loss after 40 months due to chronic rejection. Adjusted eGFR trajectories were comparable between CIK and LD (P = 0.48). Chain-ending kidney recipients, with 4 graft loss overall (1 antibody-mediated rejection and 3 vascular thrombosis), showed outcomes comparable to LD (P = 0.64 for eGFR; P = 0.57 for graft survival).
"Conclusions: The DEC-K program proved feasible, safe, and effective in expanding transplant opportunities for incompatible and hard-to-match patients."
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* Some earlier posts on deceased donor initiated chains:
I'll be speaking Sunday at the American Transplant Congress, on kidney exchange. It will be hard to squeeze in all the recent developments in my half hour, including current controversies.
"I asked Roth if he’s a libertarian, since libertarians say people should be free to do what they want as long as it doesn’t hurt others. No, Roth told me.
“People who call themselves libertarians often don’t like market regulation of any sort, but I’m a market designer,” Roth said. “I think that good regulations help markets work well.”
" Peter Coy, the veteran New York
Times economics columnist, writes about kidney exchange, after an
interview/conversation sparked by a recent working paper of mine, Market Design and Maintenance. (He's a rare economic journalist who reads economists' papers.)
He's
also a rare interviewer: his column includes the names of more of my
coauthors than I can recall in any other interview. In order of
appearance: Tayfun Sonmez and Utku Unver, Frank Delmonico, Susan
Saidman, Mike Rees (implicitly) when he names Mike's nonprofit Alliance for Paired Kidney Donation, and Elliott Peranson. Market design is, after all, a team sport."
Here's a forthcoming review paper on organ allocation and transplantation that focuses on the allocation of deceased-donor organs, particularly kidneys, and goes through the whole supply chain, from donor registration and family consent after death, to patient prioritization, and organ allocation. We also discuss the regulatory and political practices and ethical concerns that keep the availability of transplants far short of their need.
Abstract: There is a large shortage of solid organs for transplants. This survey reviews the allocation of organs (particularly kidneys), with an emphasis on how deceased donor organs are obtained and allocated in the United States but with pointers to related issues involving living donors and transplantation around the world. We review some of the key institutional details and theoretical and empirical studies and describe some open questions that we hope will continue to attract attention from researchers interested in the economic and operational aspects of organ allocation.
The paper ends with a set of open questions and research directions, followed by these concluding paragraphs about the future:
"THE DAY AFTER TOMORROW
"Efforts to quickly improve the availability of transplants include recovering more transplantable organs from deceased donors, successfully transplanting more of those recovered organs, and facilitating more living donor organ transplants of kidneys and livers. In the longer term, efforts are under way to reduce the need for human organ transplants by reducing the need for re-transplantation (after graft failure) and by preventing organ failure or curing it by other means.
"It is common to hear that xenotransplantation is tomorrow’s cure for organ failure, and always will be. However, recent developments in transplanting organs from genetically modified pigs into primates and humans suggest that the future possibilities are real, even though (as of this writing) no pig organ transplant to a human has yet survived for as much as a year (although there have now been some pig kidney and heart transplants that worked for months; Tector 2025). Another somewhat related approach involves trying to bioengineer an artificial kidney by removing from a pig kidney the pig cells that would be attacked by the human immune system, leaving a scaffold that could be populated with human kidney cells (Lo et al. 2024). Less developed so far is the hope of regrowing kidneys through some kind of stem cell manipulation, although some kidney cell growth in mice has been achieved (Araoka et al. 2025).
"Each of these lines of research offers the possibility of reducing or ending the need for, and hence the scarcity of, human organs for transplantation. That scarcity would also be reduced by medical progress in reducing the incidence and progression of kidney disease and its precursors and of other kinds of organ failure that now require transplantation. Yet it remains likely that almost everyone whose life could be extended by a human organ transplant today will die without one, and so our attention to the shortage of transplants is still needed."
" I’m writing now as I thought you might be interested in the results of this survey, which was inspired by reading your recent Wash Post column."*
Below are the three questions they asked, and the results to each one. At the survey link above you can find the responses of the individual economists surveyed.
Only one economist appeared to be skeptical about kidney exchange, and I was surprised at who it was (respondents may answer these questions very quickly...).
The next question concerns the End Kidney Deaths Act, which was introduced to the respondents at these links:
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