188 Development of WU-NK-101, a feeder cell-free expanded allogeneic memory NK cell product with potent anti-tumor activity

Background Allogeneic Natural Killer (NK) cells are emerging as a safe and effective modality for the treatment of cancer, overcoming several limitations associated with adoptive T cell therapies. Cytokine induced memory-NK offer advantages over conventional NK cells, including enhanced functional persistence, efficacy, metabolic fitness. Additionally, unlike iPSC cord blood derived they do not require engineering to enable functionality. Here we describe use WU-PRIME, GMP-grade fusion protein complex generate memory WU-EXPAND, feeder free expansion system expand create WU-NK-101. Further cryopreservation enables large-scale, off-the-shelf manufacture cancer immunotherapy, high anti-tumor activity. Methods from healthy donor leukopheresate were either activated WU-PRIME then expanded WU-EXPAND form WU-NK-101 or immediately WU- EXPAND controls cryopreserved. We compared well post- thaw functionality assessed by cytokine secretion short-term long-term anti- tumor functionality, persistence in NSG mice, activity vivo. Results followed (WU-NK-101), robustly large-scale reactions, 250-fold 14 days. The maintain durable expression CD25 after expansion, other hallmarks phenotype mass cytometry. As only, have improved vitro against K562 AML lines (TF-1, THP-1, HL-60). Notably, this is maintained upon repeated challenge. In vivo, vivo (figure 1; 50,290 v. 9,623, p<0.0001). was also leukemia models, where Memory demonstrate superior cells. Abstract 188 Figure 1 tumor-bearing mice. 10e6 cryopreserved injected into supported 50,000IU human IL-2 every day. After 9 days, harvested cheek bleed (hCD45+, CD56+, CD3) flow Conclusions data that generated using cell-free has This activation platform will development clinical translation multiple allogeneic