For decades HIV-positive patients were barred from organ donation, but recent policy changes have seen that federal ban reversed.
Now surgeons at transplant centers that meet specific requirements including involvement in clinical research can implant organs from HIV-positive patients.
The National Institutes of Health (NIH) is planning a new study in collaboration with leading transplant centers — such as John Hopkins Medicine and Mount Sinai in New York City — seeking to better understand the process of donation from HIV-positive donors to HIV-positive patients, with the aim of ultimately standardizing a single protocol and expanding the use of such procedures nationwide.
“In 20 years, there has not been any potential increase of this magnitude in the donor pool,” said Sander Florman, MD, director of the Recanati/Miller Transplantation Institute at Mount Sinai, citing a study that suggested that about 2,000 HIV-positive potential donors die each year.
More conservative estimates set the number of deceased donors closer to 500, and Florman concedes that at this point there are not enough transplant centers implanting HIV-positive patients to reach these estimates. However, he said he is excited about the prospect of shortening the wait list in the long term.
He stressed that even non-HIV patients stand to benefit from “HIV-to-HIV” implants, since the former would now have a better chance of getting the non-HIV organs — “Globally, this helps everybody,” he said.
Over 120,000 people in the U.S. are waiting for an organ transplant — roughly three-quarters of them for kidney transplants.
In 2013, Congress passed the HIV Organ Policy Equity (HOPE) Act, which reversed the ban on HIV-positive organ donors — instituted by the Organ Transplant Amendments Act of 1988 — with the caveat that transplant centers performing such surgeries were required to be part of clinical research trials and have the approval of their Institutional Review Board.
The bill also directed the Secretary of Health and Human Services to “develop and publish criteria” around transplanting organs from donors with HIV to individuals who also have HIV within 2 years of passing the law. The Secretary assigned the task of developing such criteria to the NIH, which produced its results in the fall of 2015.
The end goal was to assess the state of HIV organ transplantation and determine whether to allow the Organ Procurement and Transplantation Network to adopt a protocol for such operations.
In March, surgeons at Johns Hopkins Medicine performed the first U.S. transplant from an HIV-positive patient to two other HIV-positive patients, implanting a liver in one and a kidney in another.
The organs came from an unidentified deceased woman with HIV in New England.
Two months later, Florman and colleagues at Mount Sinai Health System followed suit, performing a similar operation — again with an HIV-positive donor and an HIV-positive recipient.
“Ten years ago the idea of transplanting someone with HIV even with [an HIV-] negative organ was almost considered an absolute contraindication,” said Florman. The fear was that giving someone with HIV — then thought to be an immunosuppressant virus — a transplant and anti-rejection drugs would suppress his or her immune system further.
“[Such patients,] in theory, might become AIDS victims,” he said.
However, several HIV-positive patients around the country and the world were transplanted accidentally — possibly as a result of false-negative tests — and to the surprise of doctors, those patients did well, Florman said.
Researchers theorized that anti-rejection medicines — e.g., cyclosporine — instead of exacerbating the problem of immunosuppression, worked synergistically with HIV medicines, he explained.
In a prospective case study of 27 HIV-positive patients in South Africa who received a kidney from other HIV-positive donors, 74% of recipients were still alive after 5 years, according to research ultimately published in the New England Journal of Medicine in February 2015.
More Research Needed
After an earlier multicenter study of HIV-negative donations to HIV-positive recipients — overseen by the National Institutes of Health — proved successful, the agency is now preparing to launch a multiyear study of HIV-to-HIV transplants.
Jonah Odim, MD, PhD, at the National Institute of Allergy and Infectious Diseases, told MedPage Today that many HIV patients are especially in need of transplants: “They have longer wait times for organs, and they suffer more mortality and more morbidity while waiting.”
Yet he also voiced some skepticism: “While there is good preliminary clinical evidence that the concept works and works very well, how that will bear out with a different type of virus in a different setting remains unknown,” Odim added, noting that viruses differ across geographies. More specifically, resistance rates and mutation rates for HIV are higher in North America than in South Africa, where the first HIV-HIV studies were completed.
“We don’t know what is going to happen when we put an HIV organ into another HIV-positive individual, because … the recipient may be under excellent control with their own anti-retroviral medications until they get an organ with a different strain,” Odim said, underscoring the risk of superinfection — where one more virulent strain dominates another.
“While theoretically interesting, it’s extraordinarily unlikely.”
If doctors know that a patient had a resistant form of HIV, Florman said they won’t do a transplant. If a deceased donor was not known to have HIV and his or her viral loads are “super high,” doctors are not likely to implant those organs either.
“The theoretical risk of getting someone’s more virulent strain of HIV that none of our new medicines treat is sub-1%, compared with the risk of staying on dialysis,” Florman said, noting that the chances of survival for even non-HIV patients on dialysis after 3 to 4 years is roughly 50% to 60%.
Even so, recipients are told in the informed-consent process that superinfection is a potential risk, he noted.
HIV patients would not be scratched from the official organ waiting list and forced to take only HIV organs, but they would be included on a short list of patients who have agreed to “extended criteria” — in this case, they’ve agreed to receive an organ from an HIV-positive donor. In the past this category also included other less-than-desirable traits, such as donors over age 55, or those with hepatitis C.
Every death meeting certain criteria is reported to an organ bank, and if the family consents and the transplant center has met the eligibility requirements, the surgery can proceed, Florman noted.
Donations from live donors are also legal, but more complex: “We don’t want to take a kidney from someone who is HIV positive and have them have a greater likelihood to have kidney disease themselves,” Florman added.
The NIH study is in the planning stages and is expected to roll out within the next 6 months.
The HOPE Act does not limit transplants to only livers and kidneys, and NIH is actively seeking centers to perform lung and heart transplants, Florman said. Current requirements regarding a set number of similar surgeries with non-HIV donors to HIV recipients are stringent, but Florman said he believes those could be relaxed in the future.
Ultimately, once enough other transplants meet the required HOPE Act criteria, the protocol would expand to other organs, including lung, heart, cornea, tissue, and valves — the same non-HIV organs that are already transplanted, Florman said.
by Shannon Firth
Washington Correspondent, MedPage Today