To investigate the anti‐leukaemic activity of dual CA IX/XII inhibition, we exposed primary AML samples derived from patients with ND (n = 5–6; Figure 4A,B) and R/R (n = 3; Figure 4C,D) FLT3 mutated AML to the dual CA IX/XII inhibitors FC531, SLC0111 and CA912 (Figure S1), as well as to Cytarabine and the highly selective FLT3 inhibitor Quizartinib. Here, CA9 is linked to acute myeloid leukemia.