ATA3271

ATA3271 is an off‑the‑shelf, allogeneic, mesothelin‑targeted CAR EBV T‑cell therapy being developed by Atara Biotherapeutics for high mesothelin‑expressing solid tumors such as malignant pleural mesothelioma, non‑small cell lung cancer, ovarian cancer, and pancreatic cancer.[2][7][8] Built on Atara’s Epstein‑Barr virus (EBV) T‑cell platform, it is an “armored” next‑generation CAR T that incorporates a PD‑1 dominant‑negative receptor (PD1DNR) to resist PD‑1/PD‑L1–mediated checkpoint inhibition and a 1XX costimulatory domain to enhance CAR T‑cell expansion, persistence, and antitumor activity while maintaining reduced allo‑cytotoxicity against HLA‑mismatched targets.[1][2][5][7][9][10] The program has been in IND‑enabling preclinical development, with prior collaboration and licensing arrangements with Bayer and Memorial Sloan Kettering Cancer Center that have since been terminated, leaving Atara with full global rights.[1][2][7][12]