Actively Recruiting
Tolerance Through Mixed Chimerism (Sip-Tego) for Kidney Transplant Recipients Receiving Combined Kidney and Bone Marrow Transplant
Led by Tatsuo Kawai, MD, PhD · Updated on 2026-06-08
12
Participants Needed
1
Research Sites
N/A
Total Duration
On this page
Sponsors
T
Tatsuo Kawai, MD, PhD
Lead Sponsor
E
Eledon Pharmaceuticals
Collaborating Sponsor
AI-Summary
What this Trial Is About
Researchers are evaluating the safety and effectiveness of the Sip-Tego regimen to induce donor-specific immune tolerance in adults with end-stage renal disease (ESRD) receiving kidney transplants. This early phase 1, open-label study involves treating six adult participants who have not shown prior immune sensitization. The study aims to reduce the need for long-term immunosuppressive drugs after kidney transplantation. The treatment includes a conditioning regimen over six days before transplantation, involving thymic irradiation, low-dose cyclophosphamide, antibody therapies (Siplizumab or ATGAM, rituximab, and tegoprubart), and infusion of bone marrow cells. Kidney transplantation and donor nephrectomy are performed using standard surgical methods. Recipients receive specific doses of the antibodies and drugs on scheduled days before and after transplant. Living donors undergo kidney removal and bone marrow collection under general anesthesia. Participants are closely monitored for immune tolerance development and safety over seven years. Researchers will assess mixed chimerism (presence of donor cells), reduction of immunosuppression, kidney graft survival, and occurrence of rejection or infections. Regular laboratory tests, imaging, and clinical evaluations will be conducted. The study includes long-term follow-up to observe adverse events and transplant outcomes.
CONDITIONS
Brief Title
Tolerance Through Mixed Chimerism (Sip-Tego)
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Male or female aged 18 to 65 years
- Chronic kidney disease stage V or end-stage renal disease treated or about to be treated with dialysis
- Candidate for living-donor kidney transplant from HLA matched or mismatched donor
- First or second kidney transplant
- EBV seropositive
- Use FDA-approved contraception methods from study start until 24 months post-transplant
- Able to understand and provide informed consent
- Negative COVID-19 test during screening and two days before procedure
You will not qualify if you...
- ABO blood group-incompatible kidney transplant
- Donor-specific antibodies within 6 months before transplant
- Persistent low white blood cell or platelet counts
- Positive for HIV-1, hepatitis B or C virus
- Untreated infections
- Heart failure with ejection fraction below 40%
- Lung function less than 50% predicted
- Pregnancy or breastfeeding
- Active cancer or high risk of cancer recurrence
- Kidney disease with high risk of recurrence in transplant
- Prior radiation therapy that limits treatment
- Genetic or family history conditions increasing radiation sensitivity
- Participation in other investigational drug studies within 30 days
- Abnormal liver function or on chronic blood thinners
- Allergy to study drugs (Cyclophosphamide, tacrolimus, Siplizumab, Tegoprubart, rituximab)
- Medical conditions preventing participation as judged by investigator, including alcohol or drug abuse
- Use of immunosuppressant medication for other diseases
- Poorly controlled diabetes or severe diabetes complications preventing normal activities
- Donors must be 18 to 70 years old, healthy with normal lab and heart/lung function, negative pregnancy test if female, and negative for certain viral infections
- Donors must pass standard evaluation for bone marrow and kidney donation
- Negative COVID-19 test during screening and two days before procedure
AI-Screening
AI-Powered Screening
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Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 screening and enrollment visit
Duration - 6 days leading up to the day of transplantation
Participants receive a conditioning regimen including thymic irradiation, low-dose cyclophosphamide, antibody administration (Siplizumab or ATGAM, rituximab, and tegoprubart), and bone marrow cell infusion in preparation for transplantation.
Daily visits for 6 days before transplant
Duration - From day 0 through day 19 post-transplant
Participants undergo combined kidney and bone marrow transplantation using standard surgical techniques, followed by administration of tegoprubart on days 0, 2, 5, 12, and 19.
Multiple visits on transplant day and follow-up visits on days 2, 5, 12, and 19
Duration - Up to 7 years post-transplant
Participants are monitored for safety, graft survival, immune function, and recovery over an extended period after treatment.
Regular follow-up visits over 7 years
Trial Site Locations
Total: 1 location
1
Massachusetts General Hospital
Boston, Massachusetts, United States, 02114
Actively Recruiting
Research Team
K
Kerry Augusta, RN
How is the study designed?
Study Type
INTERVENTIONAL
Masking
NONE
Allocation
NON_RANDOMIZED
Model
PARALLEL
Primary Purpose
TREATMENT
Number of Arms
2
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