NCT06886646: SCARR

Allogeneic Umbilical Cord Mesenchymal Stromal Cells for the Treatment of Chronic Antibody-Mediated Rejection in Kidney Transplantation

Not yet recruiting Phase 2 Last updated 26 June 2025

What this trial tests

Phase 2 trial testing Allogeneic Mesenchymal Stromal Cell Therapy in Chronic Antibody-mediated Rejection (cABMR) in 22 participants. Not yet recruiting.

Timeline

15 September 2025

Primary endpoint
15 September 2027

15 October 2029

Quick facts

Lead sponsor	Assistance Publique - Hôpitaux de Paris
Phase	Phase 2
Status	Not yet recruiting
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	triple
Primary purpose	other
Enrollment	22
Start date	15 September 2025
Primary completion	15 September 2027
Estimated completion	15 October 2029
Sites	1 location across France

Drugs / interventions tested

• Allogeneic Mesenchymal Stromal Cell Therapy
• Placebo (NaCl 0.9%) Treatment

Conditions studied

• Chronic Antibody-mediated Rejection (cABMR) — all drugs for Chronic Antibody-mediated Rejection (cABMR) →

Sponsor

Assistance Publique - Hôpitaux de Paris — full company profile →

Who can join

18 and older, any sex, with Chronic Antibody-mediated Rejection (cABMR). Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Kidney transplantation is the best treatment for end-stage chronic kidney disease (CKD), improving survival and quality of life, while reducing treatment costs. However, immunosuppressive therapies reduce acute rejection but have not significantly improved graft survival (60% at 10 years). Graft loss is largely due to chronic antibody-mediated rejection (cABMR), which remains a major challenge with no specific treatment. In our center, 20 cABMR cases confirmed by biopsy were identified in 2018-2019, with 40% of patients returning to dialysis.

Cellular therapies aiming at graft tolerance induction are promising strategies. The European consortium The-One-Study conducts Phase II trials using non-mesenchymal immunoregulatory cells to reduce immunosuppressive treatment and/or prevent infections or tumors. Mesenchymal Stromal Cells (MSCs), not part of this consortium, modulate the function of cells involved in acute or chronic rejection. In kidney transplantation (living donor), MSCs reduce acute rejection by 64% at 6 months, infections by 36%, with lower doses of immunosuppressants.

A recent randomized trial showed that injecting MSCs one and a half months after kidney transplantation allowed discontinuation of calcineurin inhibitors without increased rejection risk. At 6 months, there were no differences in renal function or tissue damage, indicating the potential to stop calcineurin inhibitors following MSC injection. Additionally, a significantly higher level of regulatory lymphocytes was observed. Previous attempts to discontinue calcineurin inhibitors early showed increased rejection risk.

A recent study (Neptune Phase Ib) with allogeneic MSCs demonstrated that tacrolimus doses could be reduced without acute or chronic rejection. In the cABMR model, MSC injection reduced creatinine by 45%, proteinuria by 70%, and fibrotic lesions. A study by Wei et al. showed that allogeneic bone marrow MSCs improved renal function in chronic rejection.

Given the easier availability of umbilical cord MSCs, which also have more significant paracrine activities, our goal is to demonstrate that allogeneic umbilical cord MSCs can serve as a treatment for cABMR.

Publications & conference data

No peer-reviewed publications indexed yet for this trial.