Interestingly, in the initial IMMU‐132‐01 phase 1/2 study9 and in the ASCENT Phase 3 trial undertaken in TNBC14, participants with Gilbert’s disease, a benign condition associated with UGT1A1*28, were excluded, whereas in the TROPiCS‐02 Phase 3 trial individuals with documented Gilbert’s syndrome were enrolled if bilirubin plasma levels were ≤ 3× upper limit of normal.22 Here, UGT1A1 is linked to Gilbert syndrome.