In an abstract presented at the 11th Annual Meeting of the Society of Hematologic Oncology (SOHO), Houston, Texas, Orca-Q, a precision-engineered cell therapy consisting of CD34+ stem cells and specific T-cell subsets, showed promising results for haploidentical stem cell transplantation (SCT) in patients with high-risk hematologic malignancies.
The study enrolled 21 adults (median age 44 years, 57% male) between January 2019 and July 2022 with high-risk hematologic malignancies who had haploidentical related donors (4/8 HLA matched). Patients received myeloablative conditioning (MAC) and single-agent GVHD prophylaxis with tacrolimus. The patients had a range of malignancies, including acute myeloid leukemia, acute lymphocytic leukemia, and chronic myeloid leukemia.
Orca-Q was successfully manufactured and delivered to all patients within 72 hours. All patients achieved successful engraftment, with relatively fast recovery of neutrophils and platelets. Severe acute GVHD (aGVHD) was rare, with only 1 case of grade III aGVHD and no cases of grade IV. Chronic GVHD (cGVHD) occurred in only 1 patient, who had mild symptoms. There were no cases of moderate-to-severe cGVHD.
Two patients died from relapsed disease during the study period, and there was a 27% estimated incidence of infections at 1 year follow-up. The GVHD-and-relapse-free survival (GRFS) rate was 71% at the same follow-up.
The study authors concluded, “Our findings suggest encouraging safety and efficacy outcomes using Orca-Q cell therapy for haplo-SCT, without PTCy, and only single agent tacrolimus. Patients treated with Orca-Q experienced a low adverse event profile, low incidence of overall and severe aGVHD/cGVHD, and improved GRFS.”
Reference
Srour SA, Salhotra A, Lowsky R, et al. Orca-Q Demonstrates Favorable Graft-Versus-Host Disease (GvHD) and Relapse-Free Survival With Haploidentical Donors Without Post-Transplant Cyclophosphamide. Abstract CT-632. Presented at the 11th Annual Meeting of the Society of Hematologic Oncology; September 6-9, 2023; Houston, Texas.
