Although a phase 1 clinical trial with GTB-3550 in AML patients (NCT03214666) showed expansion of endogenous NK cells and dose-dependent blast elimination [129], GTB-3550 was substituted by a second-generation TriKE (GTB-3650) with a humanized anti-CD16 VHH, more potent in preclinical studies [130]. Here, FCGR3B is linked to acute myeloid leukemia.