Medeor Therapeutics’ MDR-101, a donor blood-derived cell therapy that is administered as a 1-time treatment and intended to remove the daily requirement for immunosuppressant drugs in patients who receive kidney transplants, has exceeded its primary efficacy end point in a pivotal phase 3 clinical trial (NCT03363945).1
Among 20 patients who received MDR-101 following reception of an HLA-matched relative’s donated kidney, 12 patients (63%) have completed participation in the trial and have not taken their immunosuppression therapy for 2 years. As the trial’s protocol anticipated success rate was 48%, this result constitutes a surpassing of the primary end point. Furthermore, 4 more patients treated with MDR-101 are 6 months from completing participation in the trial and are currently not taking immunosuppressive therapy.
On the other hand, 1 patient withdrew from participation in the trial at the 6-month time point and 3 patients who had ceased immunosuppression therapy later resumed use of immunosuppression while still participating in the study. According to the clinicaltrials.gov page, loss to follow-up constitutes a failure of the treatment in the intent-to-treat analysis.2
“The results of this study have the potential to truly change the trajectory of the treatment for kidney transplants,” Giovanni Ferrara, MS, MBA, the president and CEO of Medeor Therapeutics, said in a statement.1 “By combining donor and recipient cells to create mixed chimerism and immune tolerance within the transplant recipient, we are working to alleviate the stress and burden of daily immunosuppressants, thereby improving quality of life and prolonged graft survival. We are buoyed by the study results presented today and look forward to the completion of our study and making MDR-101 the new treatment standard for donor matched kidney transplants.”
Key Takeaways
- Medeor Therapeutics' MDR-101, a one-time donor blood-derived cell therapy for kidney transplant recipients, has surpassed its primary efficacy endpoint in a phase 3 clinical trial, with 63% of patients not requiring immunosuppression therapy for 2 years.
- The trial's results suggest the potential to change the treatment trajectory for kidney transplants, aiming to alleviate the daily burden of immunosuppressants and improve the quality of life for patients.
- MDR-101, designed to achieve mixed chimerism and prevent rejection, has shown promising results, and the company aims to establish it as a new standard for donor-matched kidney transplants.
In addition to the 20 patients who received MDR-101, the trial also includes a control arm in which 10 patients deemed similar to the treated patients are receiving only standard-of-care immunosuppression therapy after a kidney transplant from an HLA-matched relative. At the 2-year and 3-year time points after kidney transplants, patients took the Kidney Disease Quality of Life Instrument survey. Statistically significant improvements in Burden of Kidney Disease and Mental Health on the survey were observed in the group of patients treated with MDR-101 in comparison with the patients in the control arm.
MDR-101 consists of allogeneic enriched CD34+ hematopoietic stem cells and a defined dose of CD3+ T-cells that are donated by the relative from whom the transplant recipient receives their kidney transplant. It is intended to allow patients to achieve a mixed chimerism that in turn is meant to prevent rejection of the transplanted kidney via donor-specific immune tolerance and to allow tapering off and eventually cessation of use of immunosuppressive drugs. According to the clinical trial design, participants were to taper to tacrolimus monotherapy by 6 weeks posttreatment and complete cessation of immunosuppressive therapy by 1 year posttreatment.2
"The results from this study are extremely promising,” Dixon Kaufman, MD, PhD, FACS, the medical director at the UW Health Transplant Center at the University of Wisconsin, added to the statement.1 “This innovative trial provides direction toward reducing the need for life-long antirejection medications in transplant recipients. With the achievement of mixed chimerism in this trial, we are on course to provide a safer and more effective treatment approach for many patients in need of a kidney transplant.”
The randomized, multicenter clinical trial was initiated on March 15, 2018, and remains active but is no longer recruiting new patients.1,2 It is taking place throughout the United States with locations in states including California, Colorado, Connecticut, Florida, Illinois, Minnesota, New Jersey, New York, Ohio, Pennsylvania, Texas, Utah, Virginia, and Wisconsin. The trial also has sites in Washington, DC, and Canada. In order to be included in the study, patients were required to be aged between 18 and 70 years, planning to receive their first kidney allograft from an HLA-matched and ABO-matched living relative. Patients who had underlying kidney disease with a high risk of recurrence in the transplanted kidney, were positive for donor-specific antiHLA antibody tests at baseline, were taking immunosuppressive therapy before transplant, were receiving additional solid organ transplants beyond the kidney, or showed evidence of previous infection with hepatitis B or C were excluded from participation. Separate inclusion and exclusion criteria existed for the kidney donors.
REFERENCES
1. Medeor Therapeutics Announces Interim Data from Pivotal Trial Showing Cell Therapy Technology Could Eliminate Life-Long Need for Immunosuppressant Drugs Following Kidney Transplant. News release. News release. Medeor Therapeutics. November 2, 2023. Accessed November 9, 2023. https://www.medeortx.com/news/pr-2023-11-02.php
2. Cellular immunotherapy in recipients of HLA-matched, living donor kidney transplants. ClinicalTrials.gov. Website. Accessed November 9, 2023. https://classic.clinicaltrials.gov/ct2/show/NCT03363945?term=MDR-101&draw=2&rank=1