Orca Bio, a clinical-stage biotechnology company developing high-precision cell therapies, today announced the first clinical data from its first-generation investigational therapy, Orca-T, in a phase I/II multi-center trial accepted for oral presentation at the 62nd American Society of Hematology Annual Meeting and Exposition.

The results from the single-arm, open-label trial showed that Orca-T (n=50) provided faster neutrophil (median: 12 days vs 14 days, P<0.0001) and platelet (median: 11 days vs 17 days, P<0.0001) engraftment, a decreased incidence of grade2+ acute graft versus host disease (GvHD) (at 100 days: 10% vs 30%, P=0.005) and chronic GvHD (at 365 days: 3% vs 46%, P=0.0002), and significantly higher 1-year GvHD-free and relapse-free survival (GRFS) (75% vs 31%, P=0.001) when compared to a cohort of patients who received a standard-of-care (SOC) hematopoietic stem cell transplant (HSCT) (n=144). The SOC comparator cohort was derived from contemporaneous patients treated at Stanford University with a conventional allograft.

As of the data cut-off, no patients who received Orca-T had suffered transplant-related mortality; this compares favorably to a SOC cohort (at 365 days: 0% vs 11%, P<0.04). Importantly, Orca-T demonstrated potent anti-leukemic activity in patients with active disease at transplant, suggesting that the decreased GvHD did not come at the expense of graft-versus-leukemia (GvL). While these early results of Orca-T demonstrate feasibility, more extensive studies are needed to characterize the safety and efficacy of the Orca-T approach.

“For many patients with blood cancers, a HSCT is the best hope for a cure. However, despite progress in medical management, many patients still suffer from lethal complications of HSCT. Orca-T is an investigational new drug with the potential to dramatically reduce the complications of bone marrow transplants such as GvHD and bring curative outcomes to more patients,” said Scott McClellan, M.D., Ph.D., Senior Medical Director at Orca Bio.

Allogeneic HSCT replaces a patient’s diseased bone marrow with cells from a healthy donor. With certain kinds of blood cancer, these donor immune cells can also eliminate the cancer cells and provide a cure for the patient that is durable. However, the procedure carries serious risks, including graft failure, GvHD, and infection. Orca-T is an investigational cell therapy that is designed to prevent GvHD through the use of high-purity single-cell sorted regulatory T cells to promote tolerance of the new immune system for the patient’s normal, healthy tissues.

The high-precision cellular products were successfully manufactured and scaled in a central facility and were delivered to patients at multiple clinical sites with a vein-to-vein time of fewer than 72 hours. Participating clinical sites include Stanford University; University of California, Davis; Oregon Health and Science University; University of Kansas Medical Center; Sarah Cannon Research Institute, TriStar Health Nashville; and the University of Texas MD Anderson Cancer Center.

About Orca Bio

Orca Bio is a clinical-stage biotechnology company developing a pipeline of high-precision allogeneic cell therapy therapies with the goal of safely and effectively replacing a patient’s diseased blood and immune system with a healthy one. Orca Bio’s products are biologic cell therapies designed to provide targeted donor cells to patients with the goal of increasing survival rates while decreasing toxicities. The company’s proprietary therapeutic and manufacturing platforms are exclusively licensed from Stanford University.