AMG-176 was the first selective MCL-1 inhibitor to be evaluated in the clinic, and is currently being assessed in a phase I study for efficacy, tolerability, and PK properties in patients with relapsed/refractory MM or AML (NCT02675452).518 S64315 (MIK665), another MCL-1 inhibitor derived from S63845, can induce apoptosis in diverse hematological malignancies in a Bax/Bak-dependent manner.519 It is undergoing evaluation in several phase I clinical trials in patients with relapsed/refractory AML or MDS (NCT02979366), and relapsed/refractory MM or lymphoma (NCT02992483). This evidence concerns the gene MCL1 and myelodysplastic syndrome.