Fate Therapeutics Announces New Preclinical Data for FT596 Off-the-Shelf, iPSC-derived CAR NK Cell Cancer Immunotherapy - Seite 3

About FT596
FT596 is an investigational, universal, off-the-shelf natural killer (NK) cell cancer immunotherapy derived from a clonal master induced pluripotent stem cell (iPSC) line engineered with three anti-tumor functional modalities: a proprietary chimeric antigen receptor (CAR) optimized for NK cell biology, which contains a NKG2D transmembrane domain, a 2B4 co-stimulatory domain and a CD3-zeta signaling domain, that targets B-cell antigen CD19; a novel high-affinity 158V, non-cleavable CD16 Fc receptor that has been modified to augment antibody-dependent cellular cytotoxicity by preventing CD16 down-regulation and enhancing CD16 binding to tumor-targeting antibodies; and an IL-15 receptor fusion (IL-15RF) that promotes enhanced NK cell activity. The FDA has allowed investigation of FT596 in an open-label Phase 1 clinical trial as a monotherapy, in combination with rituximab for the treatment of advanced B-cell lymphoma, and in combination with obinutuzumab for the treatment of chronic lymphocytic leukemia. In preclinical studies of FT596, the Company has demonstrated that dual activation of the CAR19 and CD16 receptors, in combination with IL-15RF signaling, convey synergistic anti-tumor activity. Increased degranulation and cytokine release were observed upon dual receptor activation in lymphoma cancer cells as compared to activation of each receptor alone, indicating that multi-antigen engagement may elicit a deeper and more durable response. Additionally, in a mixed cellular composition cytotoxicity assay comprised of CD19+ and CD19- tumor cells, FT596 combined with CD20-directed monoclonal antibody therapy effectively eliminated the heterogeneous population of tumor cells, a result that was not observed with single-antigen targeted CAR19 T cells.

About FT516
FT516 is an investigational, universal, off-the-shelf natural killer (NK) cell cancer immunotherapy derived from a clonal master induced pluripotent stem cell (iPSC) line engineered to express a novel high-affinity 158V, non-cleavable CD16 Fc receptor, which has been modified to prevent its down-regulation and enhance its binding to tumor-targeting antibodies. The product candidate is being investigated in an open-label, multi-dose Phase 1 clinical trial as a monotherapy for the treatment of acute myeloid leukemia and in combination with CD20-directed monoclonal antibodies for the treatment of advanced B-cell lymphoma (clinicaltrials.gov ID number NCT04023071). CD16 mediates antibody-dependent cellular cytotoxicity (ADCC), a potent anti-tumor mechanism by which NK cells recognize, bind and kill antibody-coated cancer cells. CD16 occurs in two variants, 158V or 158F, that elicit high or low binding affinity, respectively, to the Fc domain of IgG antibodies. Numerous clinical studies with FDA-approved tumor-targeting antibodies, including rituximab, trastuzumab and cetuximab, have demonstrated that patients homozygous for the 158V variant, which is present in only about 15% of patients, have improved clinical outcomes. In addition, ADCC is dependent on NK cells maintaining active levels of CD16 expression, and the expression of CD16 on NK cells has been shown to undergo considerable down-regulation in cancer patients, which can significantly inhibit anti-tumor activity.