Exploring the Use of Orca-T for Patients With Acute and Chronic GVHD

Mehrdad Abedi, MD, a professor of cancer, hematology/oncology, and internal medicine in the Department of Internal Medicine, Division of Hematology and Oncology at the UC Davis Comprehensive Cancer Center, discusses Orca-T, a high precision cell therapy, for patients with acute and chronic graft-vs-host disease (GVHD).

Orca Bio approached UC Davis a few years ago to start collaborative research with the Good Manufacturing Practice facility and produce these products. Each graft of the Orca-T product has stem cells and immune cells in it. The stem cells are needed to maintain the graft and allow the product to stay in the patient for a long time, according to Abedi. The immune cells cause graft-vs-leukemia effects, which is what they want.

Abedi says it is clear that there is a population of T cells called T-regulatory cells that can prevent GVHD as seen in work from multiple investigators. There are other populations, such as the naïve T cells or conventional T cells, that can cause GVHD. A smaller number of those cell may be helpful; they can cause graft-vs-leukemia, but not GVHD.

The graft is designed so that the investigators can give stem cells, but they remove a lot of conventional T cells that can cause GVHD. The graft provides a small amount of conventional T cells that can cause graft-vs-leukemia effects, as well as the regulatory T cells that can prevent GVHD, Abedi explains.