Definition

An off-the-shelf (OTS) preparation composed of human allogeneic T cells and containing primarily stem cell memory T cells (Tscm) that are transfected by electroporation with a proprietary transposon-based DNA plasmid vector (PiggyBac; PB) encoding for an undisclosed drug selection gene encoding for a selectable marker to generate close to 100% CAR-based product, a caspase-based safety switch to reduce or eliminate the product in vivo if needed, and a B-cell maturation antigen (BCMA; tumor necrosis factor receptor superfamily member 17; TNFRSF17)-specific single domain variable heavy chain (VH) chimeric antigen receptor (CAR) (VCAR), with potential immunostimulating and antineoplastic activities. The CAR T cells are also site specifically gene-edited with Cas-CLOVER (CC) to eliminate surface expression of both T-cell receptor (TCR) and beta-2 microglobulin (beta 2M) to decrease major histocompatibility complex (MHC) class I expression and further selected, by depletion of residual CD3-positive/TCR-positive cells, and expanded to yield Tscm enriched allogeneic transposed CAR T cells. Upon administration, allogeneic anti-BCMA CAR T cells P-BCMA-ALLO1 specifically recognize and induce selective toxicity in BCMA-expressing tumor cells. BCMA, a tumor-specific antigen and a member of the tumor necrosis factor receptor superfamily (TNFRSF) that binds to both a proliferation-inducing ligand (APRIL; TNFSF13) and B-cell activating factor (BAFF; TNFSF13B), plays a key role in plasma cell survival. BCMA is found on the surfaces of plasma cells and is overexpressed on malignant plasma cells.