Late Treatment With Autologous Expanded Regulatory T-cell Therapy After Alemtuzumab Induction Is Safe and Facilitates Immunosuppression Minimization in Living Donor Renal Transplantation.

BACKGROUND: The TWO Study (Transplantation Without Overimmunosuppression) aimed to investigate a novel approach to regulatory T-cell (Treg) therapy in renal transplant patients, using a delayed infusion protocol at 6 mo posttransplant to promote a Treg-skewed lymphocyte repopulation after alemtuzumab induction. We hypothesized that this would allow safe weaning of immunosuppression to tacrolimus alone. The COVID-19 pandemic led to the suspension of alemtuzumab use, and therefore, we report the unique cohort of 7 patients who underwent the original randomized controlled trial protocol. This study presents a unique insight into Treg therapy combined with alemtuzumab and is therefore an important proof of concept for studies in other diseases that are considering lymphodepletion. METHODS: Living donor kidney transplant recipients were randomized to receive autologous polyclonal Treg at week 26 posttransplantation, coupled with weaning doses of tacrolimus, (Treg therapy arm) or standard immunosuppression alone (tacrolimus and mycophenolate mofetil). Primary outcomes were patient survival and rejection-free survival. RESULTS: Successful cell manufacturing and cryopreservation until the 6-mo infusion were achieved. Patient and transplant survival was 100%. Acute rejection-free survival was 100% in the Treg-treated group at 18 mo after transplantation. Although alemtuzumab caused a profound depletion of all lymphocytes, including Treg, after cell therapy infusion, there was a transient increase in peripheral Treg numbers. CONCLUSIONS: The study establishes that delayed autologous Treg therapy is both feasible and safe, even 12 mo after cell production. The findings present a new treatment protocol for Treg therapy, potentially expanding its applications to other indications.

A review of the re-emergence of adrenocorticotrophic hormone therapy in glomerular disease, more than a drug of last resort?

There has been a re-emergence of interest in adrenocorticotropic hormone (ACTH) in patients with resistant nephrotic syndrome. We describe a patient with severe nephrosis and advanced chronic kidney disease with idiopathic membranous nephropathy resistant to conventional immunosuppressive therapies that achieved lasting remission with ACTH therapy. We explore the literature showing the extra renoprotective effects which might explain the response of proteinuric renal diseases to this treatment.