A phase 1 multicenter, single-arm study (NCT02074839) found that ivosidenib-targeted therapy in patients with mutant IDH1 (mIDH1) relapsed/refractory MDS (R/R-MDS) after failure of standard therapy resulted in a CRR of 38.9% and an ORR of 83.3% and a median overall survival (mOS) of 35.7 months. Here, IDH1 is linked to myelodysplastic syndrome.