Medeor Therapeutics’ MDR-101 is a single-dose cell therapy designed to revolutionize kidney transplantation. In a phase 3 pivotal trial, the therapy has shown remarkable promise, allowing more than half of the study participants to remain off immunosuppressants for two years.
The small study involved 20 living-donor kidney transplant recipients, and the results were nothing promising.
Out of the 20 patients, 12, or 63%, were able to remain off immunosuppressant medications for two years. Four more patients are approaching the two-year mark in the study, and they, too, have remained drug-free. Although three patients needed to resume immunosuppressants during the trial, the overall success rate exceeded initial expectations, which had been set at 48%.
MDR-101 induces mixed chimerism, a condition where a small quantity of donor blood cells persists in the recipient’s bloodstream following the infusion of donor stem cells. Initially, blood stem cells are obtained from the living donor before the transplantation. Following the organ transfer, the recipient begins a regimen of anti-rejection drugs and undergoes radiotherapy to further suppress the immune system. A few weeks later, the donor’s stem cells are introduced into the transplant recipient, where they grow in the bone marrow and other immune tissues, eventually becoming a part of the recipient’s immune system.
This phase 3 trial went a step further by testing whether kidney transplant recipients, who received an organ from a matched relative with the same transplant genes, could gradually taper off the immunosuppressant regimen within six weeks, ultimately relying on tacrolimus as their sole medication. The study also aimed to determine whether this monotherapy regimen could extend for at least two years without adverse outcomes such as graft loss, graft-versus-host disease, death, or acute kidney rejection.
In addition to the remarkable immunosuppressant reduction, Medeor’s therapy has shown significant improvements in the quality of life for transplant recipients two to three years after the procedure.
Medeor Therapeutics’ CEO, Giovanni Ferrara, expressed his enthusiasm for the study’s results and the potential impact of MDR-101 on donor-matched kidney transplants. He emphasized the goal of alleviating the daily burden of immunosuppressants, improving patients’ quality of life, and extending graft survival. The positive outcomes of the study will be presented at the American Society of Nephrology Kidney Week 2023 Annual Meeting in Philadelphia, where the therapy’s regenerative medicine advanced therapy designation from the FDA in 2020 will likely draw significant attention.
Apart from Medeor Therapeutics other biotech companies are also exploring novel approaches to enhance the life span and quality of life for organ recipients. In February, AlloVir presented evidence for their off-the-shelf, multivirus-specific T-cell therapy, posoleucel, offering potential solutions to issues related to anti-rejection medications. However, the journey is not without challenges, as seen in the merger of Talaris Therapeutics with Tourmaline Bio, emphasizing the complexities of developing new therapies for organ transplant care.
While kidney transplantation is a life-saving procedure for many end-stage renal disease sufferers, it comes with a significant trade-off – a lifetime reliance on immunosuppressant medications to prevent organ rejection. These medications can lead to severe side effects, including an increased risk of cancer, diabetes, and infections. Missing a dose or discontinuing treatment can result in irreversible organ rejection.