ATA520, an allogeneic T-cell immunotherapy targeting Wilms Tumor 1 (WT1) antigens. WT1 is an intracellular protein that is overexpressed in a number of cancers, including multiple myeloma (MM) and non-small cell lung, breast, pancreatic, ovarian, and colorectal cancers.
Memorial Sloan Kettering (MSK) has investigated ATA520 in two Phase 1 clinical studies. The first ATA520 Phase 1 study was for patients with residual or relapsed leukemia following allogeneic hematopoietic cell transplant (HCT). The second ATA520 Phase 1 study was for patients following T cell depleted HCT with relapsed or refractory MM, including plasma cell leukemia (PCL).
There is a high unmet need in patients with PCL, who are estimated to have a median survival of seven to eleven months. When PCL occurs in the context of refractory or relapsing MM, survival is estimated to be two to seven months.