Re: CAR T Cells: Off the Shelf and On the Mark
The biology of NK cells is different to T-cells. The former have rapid and potent cytotoxic, however, they do not typically expand upon encounter with antigen and lack long-term persistence.
FATE's FT516 (an iPSC-derived NK cell) has a high-affinity, non-cleavable CD16 Fc receptor to augment ADCC. FT596 (another iPSC-derived NK cell) has that, a CD19 CAR (optimised for NKs) and an IL-15RF.
With FT516, patients got three doses (either 30M, 90M or 300M per dose, on days 1/8/15), three doses of IL-2 with each infusion, and were given two cycles along with a single dose of ritiuximab (an anti-CD20 mAb). The ORR for the 90M dose was 75% and three-month CR rate was 50%. For the 300M dose, it was 71% and 57%, respectively. Five of 11 have ongoing responses at 4.6-9.5+ months.
With FT596, patients got a single dose (+/- ritiuximab), no IL-2 (due to it having cell-intrinsic cytokine support) and single cycle. The ORR for the 30M (both single and combo) dose was 17%, for the 90M dose it was 63%, and for the 300M it was 83%.
Those enrolled all had R/R B-cell lymphomas, and a number had been treated with either anti-CD19 bispecific antibodies or CAR-T. One even failed both anti-CD19 and anti-CD20 CAR-T's. The next data update will be at ASH.