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June 30 (Reuters) - The U.S. Food and Drug Administration has approved Orca Bio's cell therapy for the treatment of certain blood cancers, the regulator said on Tuesday.

The therapy, called Orca-T, brand name Tregzi, aims to treat patients with blood cancers including acute myeloid leukemia, acute lymphoblastic leukemia and myelodysplastic syndromes.

Orca-T is designed to rebuild a patient's damaged blood and immune system using healthy blood-forming and immune cells from a matched donor, while reducing serious complications associated with conventional donor stem cell transplants.

The therapy is made by separating donor blood into specific cell types, including regulatory T cells to control graft-versus-host disease, stem cells to rebuild the blood and immune system, and conventional T cells to help fight infections and cancer relapse.