Ivosidenib (AG120)

25 evaluable patients (DL1: 6, DL2: 6, DL3: 13) enrolled with a median follow-up of 16.1 months. Median age was 67 (range: 44-84). 84% (N=21) of patients had AML (ND: N=13 [TN: 8, sAML: 5], R/R: N=8), while 16% (N=4) had MDS. ELN risk was intermediate and adverse in 16% (N=4) and 56% (N=14). Median IDH1 VAF at enrollment was 22.7% (range: 5.1%-47.8%). Two patients had received a prior IDH1 inhibitor. The ORR was 92% (DL1: 67%, DL2: 100%, DL3: 100%). Composite CR (CRc: CR+CRi+CRh) was 84% (DL1: 67%, DL2: 100%, DL3: 85%) including 92% (TN: 100%, sAML: 80%), 63%, and 100% of patients with ND-AML, R/R-AML, or MDS. Median number of cycles received was 4 (DL1: 8.5, DL2: 6, DL3: 4) with ongoing responses in 62% (DL1: 33%, DL2: 50%, DL3: 82%) at 1-year. 8 patients transitioned to SCT (DL1: 0, DL2: 2, DL3: 6), and 8 patients remain on study (DL1: 2, DL2: 1, DL3: 5). 1-year OS was 68% for the entire study population (DL1: 50%, DL2: 67%, DL3: 78%), 71% in ND-AML (TN: 86%, sAML: 60%), 50% in R/R-AML, and 100% in MDS. Measurable residual disease negative CRc by multiparameter flow cytometry was attained in 60% (ND-AML: 67%, R/R-AML: 60%, MDS: 33%) correlating with improved OS (median OS: NR vs. 8.5 months, p-value: 0.038). Common grade 3/4 adverse events included febrile neutropenia (28%) and pneumonia (24%). Tumor lysis and differentiation syndrome occurred in two and four patients; all cases resolved with medical management.