The Food and Drug Administration approved Tregzi as the first regulatory T-cell-based immunotherapy for improving chronic graft-versus-host-disease-free survival in adults with blood cancers receiving a matched-donor stem-cell transplant.
Tregzi combines blood-forming stem and progenitor cells with selected donor immune cells. The aim is to rebuild blood and immune systems while lowering the risk that donor cells attack the recipient’s body after transplantation.
Approval rested on PRECISION-T, a multicenter, open-label randomized trial involving 187 adults with acute leukemia or myelodysplastic syndrome. Ninety-three received Tregzi and 94 received an unmanipulated allograft.
At one year, 78% of Tregzi recipients were alive without moderate or severe chronic graft-versus-host disease, compared with 38.4% in the standard-transplant group, FDA reported.
After accounting for death as a competing risk, 12.6% of Tregzi recipients developed serious chronic graft-versus-host disease within one year, compared with 44% of patients receiving a standard transplant.
Infections were the most common side effects and were generally consistent with the risks expected after stem-cell transplantation. FDA reported no severe infusion reactions and no graft failures during the study period.
The indication is specific: matched-donor transplantation with a myeloablative preparative regimen for adults with hematologic malignancies. It does not establish that the product is appropriate for every patient or transplant setting.
FDA granted the application Orphan Drug and Regenerative Medicine Advanced Therapy designations and approved the product for Orca Biosystems.
The randomized results establish a benefit in the approved population, but longer follow-up, real-world use and the full prescribing information remain important for understanding durability and uncommon risks.