ATA2271/ATA3271
Atara is developing a mesothelin-targeted autologous CAR T (ATA2271) for advanced mesothelioma and is also developing an off-the-shelf, allogeneic CAR T immunotherapy targeting mesothelin (ATA3271).
T and B-cell fractions are separated from a healthy donor via leukapheresis. The CD19+ fraction is transformed with EBV, generating an EBV+ lymphoblastoid cell line (BLCL). T cells are stimulated with BLCLs prior to retroviral introduction of mesothelin (MSLN)-targeted CAR with 1XX signaling domain and PD1DNR. The mesothelin scFv is derived from human anti-MSLN antibody m912. Continued expansion of MSLN-1XX-PD1DNR CAR+ EBV T cells (ATA3271) occurs with BLCL stimulation prior to harvest and cryopreservation for later use.