Atara Biotherapeutics Provides Update on ATA2271 Autologous CAR T Trial

Atara Biotherapeutics said Memorial Sloan Kettering paused enrollment in its phase 1 clinical study of the company’s experimental CAR T therapy ATA2271 for mesothelioma to gather and review information after a patient treated in the study died.

Photo: Jakob Dupont, head of global research and development at Atara

ATA2271 is a next-generation, autologous chimeric antigen receptor (CAR) T-cell therapy targeting mesothelin in development in patients with malignant pleural mesothelioma. The single case involved a patient with a history of multiple malignancies and other comorbidities undergoing treatment for advanced recurrent mesothelioma. MSK is in the process of further evaluating the occurrence, including the extent of the relationship of the event to ATA2271.

“The safety of every patient participating in studies we are funding or conducting is of the utmost priority for Atara,” said Jakob Dupont, head of global research and development at Atara. “Clinical evaluation of the case remains ongoing, and we are working closely with investigators at MSK, who are conducting the ATA2271 study under their IND, to establish the underlying causes of the event. We anticipate providing a further update in the coming weeks following further discussion and consultation with MSK.”

The median survival of treated patients with malignant pleural mesothelioma is 9-17 months even with successful completion of a combination of chemotherapy, aggressive surgical resection, and radiation therapy. The first six patients enrolled in the two lowest dose cohorts received either 1×106 cells/kg (patients 1-3) or 3×106 cells/kg (patient 4-6) intrapleural ATA2271. Within these two cohorts, no dose limiting toxicities have been reported to date. The patient event being reported relates to the first patient in a third, higher-dose cohort (6×106 cells/kg).

Author: Rare Daily Staff