NCT03707262

Study of Combined Kidney and Blood Stem Cell Transplant From a Brother or Sister Donor

Donor Chimerism and Graft Survival Following Combined HLA-Identical Sibling Living Donor Kidney and Hematopoietic Stem Cell Transplantation Utilizing a Conditioning Regimen of Total Lymphoid Irradiation and Rabbit Anti-Thymocyte Globulin

• Status: Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 15 (estimated)
• Sponsor: Jeffrey Veale, MD · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this study is to find out if an investigational treatment will allow kidney transplant recipients to better accept their new kidney and stop immunosuppressive medicines. This study is for kidney transplant recipients who receive a kidney from a sibling donor. The investigational treatment is started after kidney transplant. It begins with a regimen of a drug called rabbit anti-thymocyte globulin (rATG) combined with radiation therapy (known as total lymphoid irradiation, or TLI) to the lymph nodes and spleen. This is followed by an infusion of blood stem cells, which will be donated by the same sibling who donated their kidney. Researchers think that this treatment allows immune cells from the donor and recipient to live side by side, a condition referred to as "mixed chimerism." Mixed chimerism may help create a state of "tolerance" in kidney transplant recipients in which all immunosuppressive medications can be stopped without rejection of the transplanted kidney. This study will test whether (1) the investigational treatment will allow patients to stop immunosuppressive medications after their kidney transplant and (2) if the treatment impacts the rate of kidney rejection and the side effects of immunosuppressive medications.

Detailed description

In spite of the pronounced benefit of kidney transplantation in prolonging survival and improving the quality of life of patients with end stage renal disease, it is still hampered by the risk of graft rejection and the need for lifelong immunosuppression. Researchers have sought to circumvent these challenges through the use of combined kidney and hematopoietic stem cell transplantation to induce immune tolerance. This study will build upon published reports showing favorable results for the TLI/rATG regimen in HLA-matched living donor transplant recipients. The investigators seek to confirm that patients treated with total lymphoid irradiation (TLI) and rabbit anti-thymocyte globulin (rATG) followed by human leukocyte antigen (HLA)-identical donor hematopoietic progenitor cell transplant can be withdrawn from immunosuppressive drugs while maintaining normal renal function after renal transplantation. At serial time points, (1) graft function will be monitored, (2) chimerism will be measured in recipient white blood cell subsets, and (3) protocol biopsies of the graft will be obtained. An attempt will be made to discontinue tacrolimus at 12 months if the following conditions are met: (1) chimerism (defined as ≥5% donor type cells among the T cells, B cells, Natural Killer \[NK\] cells, and granulocytes) is detectable for at least 180 days after CD34+ and CD3+ cell infusion, (2) stable graft function without clinical rejection episodes is maintained, (3) there is lack of histologic rejection on protocol biopsies, and (4) there is no evidence of graft vs. host disease (GVHD). Recipients in the proposed study will be given a target dose of ≥ 5 x106 CD34+ cells/kg and 5x106 CD3+ cells/kg with the goal of achieving durable mixed chimerism.

Conditions

• Renal Transplant Rejection
• Tolerance
• Kidney Transplant

Interventions

Type	Name	Description
BIOLOGICAL	Donor CD34+ and CD3+ cells	Infusion of GCSF-mobilized, Miltenyi-enriched CD34+ hematopoietic stem/progenitor cells (HSPCs) (≥ 5 million cells/kg) and CD3+ cells (5 million cells/kg) from an HLA-identical sibling living donor, following pre-conditioning regimen of rATG and TLI.

Timeline

• Start date: 2019-11-06
• Primary completion: 2026-02-01
• Completion: 2026-02-01
• First posted: 2018-10-16
• Last updated: 2025-11-26

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study