MENLO PARK, Calif., June 30, 2026
Orca Bio announced that the U.S. Food and Drug Administration (FDA) has approved TREGZI™ (allogeneic regulatory T cell immunotherapy with HSPC and T cells-vldq), clinically known as Orca-T®, making it the first and only FDA-approved precision-engineered cell therapy designed for matched-donor allogeneic hematopoietic stem cell transplantation in adults with hematological malignancies. The therapy is indicated to support hematopoietic and immunologic reconstitution while improving chronic graft-versus-host disease-free survival (cGFS) following myeloablative conditioning. The approval represents Orca Bio’s first commercial product and validates the company’s proprietary high-precision cell therapy platform, offering a personalized treatment approach aimed at improving transplant outcomes while reducing long-term complications associated with conventional allogeneic stem cell transplantation.
Phase 3 Precision-T Trial Demonstrated Significant Survival Benefits
The FDA approval is supported by results from the pivotal Phase 3 Precision-T study involving 187 adult patients with acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), myelodysplastic syndrome (MDS), and mixed-phenotype acute leukemia (MPAL). Patients receiving TREGZI plus single-agent tacrolimus achieved a 78% chronic GVHD-free survival rate at 12 months, compared with 38% in patients receiving conventional allogeneic hematopoietic stem cell transplantation with tacrolimus and methotrexate. The study also demonstrated a 94% overall survival rate with TREGZI compared to 83% for standard transplantation. Chronic GVHD incidence declined dramatically to 13% versus 44%, while non-relapse mortality was reduced from 13% to just 3%. Additional clinical benefits included improved GVHD-free relapse-free survival, fewer severe acute GVHD events, and a lower incidence of serious infections, highlighting the therapy’s potential to transform outcomes for patients undergoing stem cell transplantation.
Precision-Engineered Cell Therapy Targets Immune Recovery and GVHD Prevention
Unlike conventional transplant approaches, TREGZI is manufactured individually for each patient using living cells collected from a matched donor. The therapy combines hematopoietic stem and progenitor cells (HSPCs) to rebuild the immune system, highly purified regulatory T cells (Tregs) to suppress harmful immune responses responsible for graft-versus-host disease, and conventional T cells that help restore immune function while maintaining the beneficial graft-versus-leukemia effect. Orca Bio stated that this precision-engineered composition enables clinicians to reduce transplant-related toxicities without compromising anti-cancer activity. Company leadership described the approval as a defining milestone that validates decades of research into regulatory T-cell biology and establishes a scalable platform for personalized cell therapies designed to improve both survival and quality of life following transplantation.
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Commercial Launch Marks New Era for Precision Cell Therapy
With FDA approval secured, Orca Bio is transitioning into a commercial-stage biotechnology company focused on delivering TREGZI to eligible transplant centers across the United States. The approval positions the company at the forefront of precision-engineered allogeneic cell therapies while supporting continued development of additional programs targeting blood cancers and autoimmune diseases. Hematological malignancies such as AML, ALL, and MDS continue to present high relapse rates and significant treatment-related complications despite advances in therapy. By significantly improving chronic GVHD-free survival, reducing severe infections, and lowering transplant-related mortality, TREGZI introduces a new standard for personalized stem cell transplantation. The approval also strengthens Orca Bio’s long-term strategy to expand its precision manufacturing platform and develop next-generation engineered cell therapies capable of improving outcomes across multiple serious hematologic disorders.
Source: Orca Bio, press release
