The first (unsuccessful) human-to-human kidney transplant took place 75 years ago. Some 16 years later, the first successful human transplant took place. Now, according to the United Network for Organ Sharing (UNOS), there are currently 111,714 people in the US awaiting organ transplantation. Approximately 20,000 of these are so called “hard-to-match” kidney transplant patients.
In other words, their immune systems will reject most kidneys because of antibodies circulating in their blood that react to proteins known as human leukocyte antigens (HLA). These proteins are found on most cells and are used by the immune system to recognize what is foreign to the body.
In HLA-sensitized patients, the body has been exposed to foreign HLA in the past, either through pregnancy, blood transfusion or previous kidney transplant. As such, it immediately recognizes most donor organs as unfamiliar. And, unless these antibodies can be removed, they will result in severe antibody mediated rejection (AMR) and early loss of the transplanted organ.
Apart from the scarcity of donor kidneys, the biggest barrier to kidney transplant is the percentage (nearly 1:3) of patients on the waiting list whose immune systems make them likely to reject most kidneys available to them. Highly HLA-sensitized patients are very difficult to match with less than 7% receiving transplants each year.
SRxA’s Word on Health was therefore interested to hear of a new study from Johns Hopkins which showed that desensitizing such patients with a combination of therapeutic plasmapheresis and intravenous immunoglobulin (IVIG) doubled their chance of survival eight years after transplant surgery, as compared with those who stay on dialysis awaiting compatible organs.
Additionally, the protocol enabled a dramatic 98% transplant rate rather than the traditional 7%.
“The results of this study should be a game changer for health care decision makers, including insurance companies, Medicare and transplant centers,” said lead investigator Robert A. Montgomery, M.D., D. Phil. “There’s a dramatic survival benefit, so people should take note. If this were a cancer drug that doubled chances of survival, people would be lined up out the door to get it. It’s really extraordinary to go from 30 percent survival to 80 percent survival after eight years.”
Widespread use of the pre-surgery protocol developed at Johns Hopkins could potentially lead to 3,000 more kidney transplants from living donors each year. The protocol uses plasmapheresis to remove the HLA from the blood before the transplant, then the patient receives low-dose intravenous immune globulin (a human plasma protein) to replace the problematic antibodies and prevent their return. This process is performed every other day for several days before transplant and then for up to 10 days following the surgery.
Although the protocol has great benefit in living donor transplants, it cannot be used in patients receiving cadaver organs – where time is of the essence, because several days of plasmapheresis and IVIG are needed before surgery can take place.
Additionally, the patient will still to take the same anti-rejection drugs as all other organ transplantation patients.
The desensitization protocol also makes kidney transplants more expensive, However, the cost savings when compared to remaining on dialysis are enormous. Better still, the patient no longer has to endure the difficulties of dialysis, a process that takes about five hours a day, three days a week, and which often makes the tasks of daily life from working to caring for children nearly impossible.
“This treatment increases survival, ensures a better lifestyle and saves the health care system money,” says Montgomery. “There aren’t many things like that.”
Let’s hope healthcare insurers are reading this and taking note.
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