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Phase 1Active, not recruitingNCT05973734

Islet transplantation with recipient Tregs or donor bone marrow

Trial testing donor-islet transplantation combined with recipient regulatory T cells or deceased-donor vertebral bone marrow therapy to improve immune tolerance. As of July 2026 it is listed on ClinicalTrials.gov as enrolling by invitation only — it is no longer open to unsolicited applicants.

Primary endpoints

  • Occurrence of Grade 3 to 5 cytokine release syndrome / acute infusion reaction after Treg administration infusion reaction after Treg administration
  • Occurrence of grade 4 or greater adverse events of islet transplantation
  • Number of patients who receive Treg infusions (Arm1) or Donor Derived Vertebral Bone Marrow (Arm2) and islet transplantation (feasibility)

Results so far

No results posted yet. The registry lists a target enrolment of 24 and primary completion in December 2030.

The full picture

What is being tested and why it matters

Transplanting insulin-making islet cells from a deceased donor can restore glucose control in type 1 diabetes, but the immune system attacks the new cells — so recipients need lifelong anti-rejection drugs whose side effects usually outweigh the benefit for all but the most severe cases. This Phase 1 study at Stanford asks whether the transplant can be made to last by teaching the immune system to tolerate it instead.1

It has two arms. One infuses the recipient's own regulatory T cells (Tregs) — the immune cells whose job is to hold other immune cells back — collected by apheresis, expanded in the lab, and given back alongside the islets. The other infuses vertebral bone marrow from the same deceased donor as the islets, an approach intended to nudge the recipient's immune system toward accepting donor tissue.1

Where it stands

This is an early safety and feasibility study, not an efficacy trial. The main endpoints are whether severe cytokine release syndrome or infusion reactions occur after the Treg infusion, whether grade 4 or worse adverse events follow the islet transplant, and simply whether the combined procedure can be delivered at all. Target enrolment is 24 adults aged 18-70; the trial started in April 2024 and primary completion is not expected until December 2030. No results have been posted.1

Can you join?

Not by applying. As of July 2026 ClinicalTrials.gov lists this study as enrolling by invitation — participants are identified and approached by the study team, and it is not open to unsolicited applicants.1 If you are interested in islet transplantation, the registry entry is still worth reading for context, but this particular study is not one you can put your name forward for.

References

  1. ClinicalTrials.gov. Clinical Islet Transplantation With Apheresis, Isolation and Reintroduction of Recipient Regulatory T Cells (NCT05973734). https://clinicaltrials.gov/study/NCT05973734 ↩ ↩2 ↩3 ↩4