The replacement of the carboxamide linkage with an imidazole (see compound 27 in Figure 9) led to picomolar LSD1 inhibition, together with nanomolar anti-clonogenic activity in THP-1 cells and in vivo good efficacy after oral administration in mouse leukemia models (Romussi et al., 2020). The gene discussed is KDM1A; the disease is leukemia.