Orca Bio Presents New Data at the 2026 Tandem Meetings of ASTCT® and CIBMTR® Reinforcing Orca-T® as a Durable, High-Precision Cell Therapy for Hematological Malignancies

New retrospective analysis showed Orca-T with reduced intensity conditioning (RIC) demonstrated favorable OS, RFS and GRFS compared to PTCy

Company announced first patients dosed in the Phase 2 SERENE-T study evaluating Orca-T with RIC

Orca-T demonstrated superior OS and RFS with reduced non-relapse mortality in patients with myelodysplastic syndromes compared to PTCy-based transplants

New manufacturing and distribution report found 100% of Orca-T products were distributed within 70 hours vein-to-vein time with consistent purity

Patients with haploidentical donors treated with Orca-Q® showed promising outcomes in survival, GVHD and relapse-free survival

MENLO PARK, Calif.--(BUSINESS WIRE)--Orca Bio, a late-stage biotechnology company committed to transforming the lives of patients through high-precision cell therapy, today announced new clinical data presented at the 2026 Tandem Meetings of ASTCT® and CIBMTR® from February 4-7 in Salt Lake City.

Orca-T with Reduced Intensity Conditioning

“Patients undergoing reduced intensity conditioning allogeneic stem cell transplantation often face a tradeoff between tolerability and long-term disease control,” said Caspian Oliai, MD, medical director of the UCLA Bone Marrow Transplantation Stem Cell Processing Center, and primary investigator on the SERENE-T Phase 2 study. “The clinical evidence being generated today, which suggests Orca-T may improve key outcomes by reducing GVHD without increasing infection risk or relapse rate, provides a strong foundation for our ongoing evaluation of Orca-T in this setting. The dosing of the first patients in the Phase 2 SERENE‑T study further strengthens this initial momentum, representing a meaningful step forward in expanding the investigation of Orca‑T for patients undergoing reduced intensity conditioning.”

SERENE-T (NCT07216443) is a new multicenter, open-label Phase 2 trial evaluating the safety, tolerability and efficacy of Orca-T, Orca Bio’s lead investigational allogeneic T-cell immunotherapy, in patients with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) undergoing reduced intensity conditioning (RIC) or non-myeloablative conditioning (NMA). The first patients were treated this year at Vanderbilt University, UCLA and Oregon Health & Science University (OHSU) - Knight Cancer Institute. The study continues to enroll patients with plans to open at additional transplant centers across the U.S.

A new analysis compared outcomes from the single-center, open-label Phase 1 investigator-sponsored trial evaluating Orca-T versus a historical cohort of patients from the CIBMTR registry who received a conventional allogeneic hematopoietic stem cell transplant (alloHSCT) with post-transplant cyclophosphamide (PTCy). All patients were aged 60-75 (median 68 years), had a 7/8 or 8/8 human leukocyte antigen (HLA)-matched donor, and were given a RIC for the treatment of AML, acute lymphoblastic leukemia (ALL), MDS or myeloproliferative neoplasm (MPN).

Patients receiving Orca-T (n=53) compared with PTCy (n=587) demonstrated improved:

• Overall survival at one year (OS; 88% vs 72%) and two years (84% vs 61%)
• Relapse-free survival at one year (RFS; 82% vs 61%) and two years (79% vs 53%)
• Graft-versus-host-disease relapse-free survival at one year (GRFS; 72% vs 54%) and two years (72% vs 45%)
• Relapse rates at one and two years (9.7% vs 23%, 9.7% vs 30%) and non-relapse mortality at one and two years (NRM; 8% vs 16%, 12% vs 17%).

At one year, rates of Grade 3-4 acute and moderate-to-severe chronic graft versus host disease (aGVHD, cGVHD) were 0% and 10% with Orca-T, respectively, compared to 6% and 10% with PTCy. At two years, rates of cGVHD were 10% with Orca-T and 12% with PTCy.

Orca-T Versus PTCy in Patients with Myelodysplastic Syndromes

A post-hoc analysis of patients aged 18-65 with MDS compared pooled results from the Phase 3 Precision-T study and the Phase 1b study of Orca-T to a historical cohort from the CIBMTR registry of patients who received a conventional alloHSCT and PTCy in the myeloablative conditioning (MAC) HLA-matched setting. Patients with MDS who were treated with Orca-T (n=25) demonstrated higher one-, two- and three-year OS of 100% compared to the PTCy cohort (n=95) with 80%, 70% and 62%, respectively. At one year, the Orca-T arm showed RFS of 95% versus 64% with PTCy and NRM of 0% versus 9.9%, respectively. Notably, these trends were observed across subgroups including age and donor type.

A similar analysis was conducted across multiple hematologic malignancies, including MDS, AML and ALL with consistent results. In this post-hoc analysis, Orca-T (n=164) demonstrated higher OS compared to PTCy (n=380) at one, two and three years (94% vs 82%, 85% vs 73% and 82% vs 65%, respectively). At one year, RFS was 78% with Orca-T compared with 70% with PTCy, while NRM was 2.7% versus 7.7%, respectively. These findings were consistent with the results observed in a subgroup of patients over 50 years of age.

Reliable Manufacturing and Nationwide Distribution of Orca-T

A manufacturing and distribution analysis from the Phase 3 and Phase 1b Orca-T studies conducted between December 2019 and September 2024 reported on the production of 243 clinical cell therapies, including 215 from single-day and 28 from two-day collections. Overall, 100% of products were delivered to transplant centers across the U.S. within 70 hours, with 99% infused within 72 hours. Product quality was consistent across all three Orca-T components: hematopoietic stem cells, regulatory T-cells and conventional T-cells.

These results demonstrate the feasibility of reliably manufacturing and distributing Orca-T at scale while maintaining high product purity within a controlled logistics framework, supporting multicenter clinical studies and potential future commercial application.

“These data continue to reinforce the strength of Orca-T across both clinical outcomes and operational execution,” said Nate Fernhoff, Ph.D., co-founder and chief executive officer at Orca Bio. “The consistency of these results, along with our ability to reliably manufacture and deliver Orca-T across the U.S., highlights the potential of this therapy to make a meaningful difference for patients with hematologic malignancies. As we move toward a potential launch later this year, we remain focused on executing with the same level of commitment and rigor to support patients, clinicians and transplant centers.”

Orca-Q for Patients with Haploidentical Donors

New findings from the ongoing Phase 1 study of Orca-Q, Orca Bio’s second-generation investigational allogeneic T-cell immunotherapy, evaluated 39 patients with AML, ALL or MDS and a haploidentical donor who received MAC with Bu/Flu/Thiotepa (BFT), TBI/Flu/Thio (TFT) or TBI/Flu. All patients engrafted by Day +19 (median 11 days) and demonstrated encouraging rates of OS at one, two and three years (80%, 77% and 77%, respectively). Patients demonstrated RFS of 77% and GRFS of 72%, with low incidences of Grade 3-4 aGVHD at Day +180 and moderate-to-severe cGVHD at one year (8.1% and 0%, respectively). Outcomes were further improved in the TFT subgroup (n=14) across OS (85%), RFS (85%), GRFS (85%), aGVHD (0%) and cGVHD (0%).

About Orca-T

Orca-T is an investigational allogeneic T-cell immunotherapy under evaluation for the treatment of multiple hematologic malignancies including acute leukemias and myelodysplastic syndromes. Orca-T is composed of highly purified regulatory T-cells, hematopoietic stem cells and conventional T-cells derived from either related or unrelated matched donors. Orca-T has received Regenerative Medicine Advanced Therapy (RMAT) and Orphan Drug Designation for the prevention of graft versus host disease or death in patients eligible for hematopoietic stem cell transplant from the U.S. Food and Drug Administration (FDA). The Biologics License Application (BLA) for Orca-T is currently under Priority Review with the FDA with a Prescription Drug User Fee Act (PDUFA) target action date of April 6, 2026.

About Orca-Q

Orca-Q is Orca Bio’s second-generation investigational allogeneic T-cell immunotherapy being evaluated in clinical trials for the treatment of multiple hematologic malignancies, including in patients with haploidentical and mismatched donors. Orca-Q is a proprietary composition of stem cells combined with specific T-cell subsets derived from healthy donors and engineered by Orca Bio’s high-precision platform.

About Orca Bio

Orca Bio is a late-stage biotechnology company developing high-precision cell therapies for the treatment of blood cancer and autoimmune diseases. The company’s manufacturing platform uses single-cell precision to create proprietary, uniquely-defined products designed to replace a patient’s diseased blood and immune system with a healthy one. At Orca Bio, we are on a mission to redefine what’s possible for patients by transforming the field of curative allogeneic cell therapy. For more information, visit www.orcabio.com.

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