Kidney Transplantation: Expanding Access

Benjamin Hippen, MD, FASN, FAST, is the senior vice president and head of Transplant Medicine for Fresenius Medical Care. He leads the company’s worldwide efforts to expand access to and understanding of transplant medicine. As a general and transplant nephrologist, Dr. Hippen has in-depth knowledge of the full spectrum of renal care.

A: Fresenius Medical Care is working to support kidney transplantation by looking at the barriers to kidney transplantation for our patients, starting from the point of referral to receiving a transplant.

In the United States, we’ve tried to standardize the process to refer patients for transplant. It may be surprising to hear, but there are over 250 kidney transplant programs. Each of the referral forms they use vary, and many still require that we fill those forms out by hand.

With a small team, we were able to create a “point and click” transplant referral form that allows our social workers to assemble a 15- to 20-page PDF with the key demographic, psychosocial, clinical, regulatory, and financial information that a transplant center needs to get a transplant evaluation started. Our clinical teams can securely send that PDF transplant referral electronically to any transplant center through any platform. We rolled that out across the entire U.S. Fresenius Kidney Care enterprise in April of 2023. Since April, the transplant referral packet has been widely used. It’s been successfully sent to about 180 different transplant programs in the United States. We've seen about a 40 percent increase in the number of new transplant referrals over the course of 2023 compared to 2022.

We're also very involved in public policy efforts to improve access and reduce barriers to transplantation, and we do that in conjunction with a number of other professional societies, including the American Society of Transplantation, the American Society of Nephrology, and Kidney Care Partners.

Finally, Fresenius Medical Care is a member of the American Society of Transplantation Living Donor Circle of& Excellence, which means that any U.S.-based full-time employee can receive 100 percent paid time off for six weeks if they become a living organ donor.

A: Our primary focus has been in North America in part because most of the barriers with access to transplantation are in the United States. Our colleagues in Europe do an excellent job of getting their patients referred and waitlisted for transplantation. There are probably pockets of opportunity for improvement there, but if we were able to get the United States up to the level of our colleagues in Europe, we’d revolutionize access to transplantation for our patients.

If somebody is interested in becoming a living kidney donor, usually the first thing they do is get in touch with a transplant center that does living kidney donation. There are widely used and accepted screening guidelines for being a living kidney donor. This typically involves seeing a transplant nephrologist, which is a nephrologist who has undertaken additional special training in kidney transplantation. They are also trained to evaluate the safety of both the procedure and the long-term risk of living kidney donation.

The donor candidate can expect to go through a number of different blood tests and x-rays. They also have to see and speak with someone called an independent living donor advocate to make sure they are not acting under any sort of duress or secondary gain.

Once all the testing is done and the donor candidate has seen all the members of the transplant team, their case is presented to the transplant selection committee and their candidacy to be a living donor is either accepted or rejected.

Generally speaking, someone without high blood pressure, diabetes, elevated body mass index, or a strong family history of kidney disease or family history of genetic markers that are risk factors for developing kidney disease, can be a suitable candidate for living kidney donation. There are exceptions, but usually we’re looking for individuals who are healthy and don’t have a personal or family history that would suggest a high risk of developing kidney disease in the future.

For somebody to receive a living donor kidney transplant, there's a number of tests that have to be performed for both the donor and the recipient. One of the most important tests is to see whether or not the recipient is compatible with the living donor, making sure that the recipient doesn't make antibodies against the donor’s kidney.

If the recipient makes antibodies against the donor kidney, those antibodies are referred to as “donor-specific antibodies.” While it's possible to undertake kidney transplantation when donor-specific antibodies are present, that typically involves using a lot more immunosuppression, which carries its own risks. It's generally not ideal.

For people who have donor-specific antibodies against their designated recipient, there are sometimes opportunities for that donor-recipient pair to swap or trade. In fact, paired exchanges now make up about 40 percent of all living donor kidney transplants in the United States.

I think that xenotransplantation has moved forward with more speed and more intensity than many of us expected even a few years ago. Xenotransplantation means transplanting an organ from an organism that's not a human being. In this case, that organism is a pig.

Xenotransplants, as they're currently being considered, are procured from genetically modified pigs, and the genetic modifications are specifically designed to prevent the human immune system from aggressively rejecting the pig kidney. People who get these kidneys will still need immunosuppression, but the idea here is that the very aggressive response of the immune system without those genetic modifications are taken care of by those genetic modifications. There's still a long way to go, but to my mind, that's one of the most interesting and exciting innovations in transplantation to come along.