Tregzi (allogeneic regulatory T cell immunotherapy with HSPC and T cells-vldq): FDA approval, pivotal trial and safety
Approved
Type
Cell therapy
FDA-approved use
Use in matched donor hematopoietic stem cell transplantation with myeloablative preparative regimen,for hematopoietic and immunologic reconstitution and to improve chronic graft-versushost disease (cGVHD)-free survival, in the treatment of adults with hematologicalmalignanciesWording from FDA's list of novel approvals.
Company
Orca Biosystems
Application
BLA 125868
Specialty
Hematology
At a glance
Tregzi is an allogeneic cell therapy of donor regulatory T cells, stem and progenitor cells, and conventional T cells. It is approved for adults with hematologic malignancies having matched donor transplant after myeloablative conditioning, to aid blood and immune recovery and improve survival free of chronic GVHD. In the phase 3 Precision-T trial, survival free of moderate-to-severe chronic GVHD was higher than with a standard graft (hazard ratio 0.26; 95% CI 0.14-0.47; P<.001). Graft failure, GVHD, infusion reactions, secondary malignancies and infections are the main risks.
What it is and how it works
Tregzi is made from mobilized blood of an HLA-matched donor. Regulatory T cells are given first to restrain GVHD, and conventional T cells follow about two days later to speed immune recovery. Stem and progenitor cells in the product restore blood cell production. Standard transplants use an unmanipulated graft with broader immunosuppression for GVHD prophylaxis. Tregzi is meant to be given with a single calcineurin inhibitor.
Multicenter, open-label, randomized phase 3 trial. Grafts came from G-CSF-mobilized peripheral blood of 8/8 HLA-matched sibling or unrelated donors after myeloablative conditioning.
Patients
187 adults with acute leukemia in remission or MDS eligible for transplant (93 randomized to Tregzi, 94 to control). Median age was 44 years. Prior allogeneic transplant was excluded.
Compared with
Unmanipulated allograft with tacrolimus and methotrexate.
Primary endpoint
Survival free of moderate-to-severe chronic GVHD (cGVHD-free survival), judged by an independent review committee.
Result
Significantly higher with Tregzi (hazard ratio 0.26; 95% CI 0.14-0.47; P<.001). One-year estimates were 78.0% with Tregzi vs 38.4% with control.
Other results
One-year moderate-to-severe chronic GVHD was 12.6% vs 44.0% (P<.001). Overall survival was 93.9% vs 83.1% (P=.12). GVHD-free and relapse-free survival was 63.1% vs 30.9% (P<.001). Nonrelapse mortality was 3.4% vs 13.2% (P=.03).
Safety in the trial
88 patients were treated with Tregzi. Serious adverse reactions in the first 100 days occurred in 28%, mainly bacterial infections, pyrexia, venoocclusive liver disease, and viral infections. Fatal adverse reactions occurred in 3 patients (3%). Grade 3-4 mucositis was 28%. Authors reported fewer serious infections and less nonrelapse mortality than control.
How does Tregzi (allogeneic regulatory T cell immunotherapy with HSPC and T cells-vldq) compare with the alternatives (Tacrolimus plus methotrexate, Post-transplant cyclophosphamide, Cyclosporine-based regimens) for its approved use (use in matched donor hematopoietic stem cell transplantation with myeloablative preparative regimen,for hematopoietic and immunologic reconstitution and to improve chronic graft-versushost disease (cGV…? Summarize head-to-head and indirect evidence, efficacy, safety and where each fits, with citations.
There is no boxed warning. Warnings cover graft failure, acute and chronic GVHD (including life-threatening and fatal cases), infusion reactions including anaphylaxis, secondary and donor-origin malignancies, and transmission of infectious agents. Common adverse reactions included mucositis, diarrhea, rash, infections of several types, abdominal pain, vomiting, nausea, hemorrhage, acute GVHD, and edema. Grade 3-4 cytopenias were common. Premedication is advised for infusion reactions, and patients need monitoring for hematopoietic recovery, GVHD, and infection.
What it competes with
Adults undergoing myeloablative matched donor transplant usually receive an unmanipulated graft with calcineurin inhibitor-based GVHD prophylaxis. Regimens differ by center and donor type.
Tacrolimus plus methotrexateConventional calcineurin inhibitor-based prophylaxis with an unmanipulated graft, and the comparator in the pivotal trial.
Post-transplant cyclophosphamideAlternative GVHD prophylaxis used with several donor types and graft sources.
Cyclosporine-based regimensCalcineurin inhibitor option, often combined with methotrexate or other agents.
Anti-thymocyte globulinAdded to prophylaxis in some settings, mainly with unrelated donors, to reduce GVHD.
Bottom line for clinicians
Tregzi suits adults with acute leukemia or MDS who are candidates for myeloablative transplant from a matched sibling or unrelated donor. The trial showed benefit in chronic GVHD-free survival, with a lower rate of moderate-to-severe chronic GVHD, but the overall survival difference was not significant. Weigh this against the need for specialized cell processing, graft failure, GVHD, and infection risk. Trial follow-up and the open-label design also matter.
Dosing, contraindications and full warnings are in the prescribing information.
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Last updated October 28, 2026 by 2 Minute Medicine.
For healthcare professionals. A summary of public FDA documents and published trials, not medical advice. Check the full prescribing information before prescribing.
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