Variant allele frequency of mutations and course of platelet count prior to and during PEM therapy. (A) Variant allele frequency of single-nucleotide variants detected in IDH1, IDH2, ASXL1, RUNX1, and STAG2 in the patient before and during treatment with PEM. Analyses were done using published methods (panel next-generation sequencing analysis for 54 mutations; Trusight Myeloid Panel) including targeted ultradeep analysis for IDH1 and IDH2 with a sensitivity down to 0.1%.¹⁹  (B) After diagnosis of MDS EB-1, the patient presented with persistent thrombocytopenia. Two months after PEM treatment initiation, platelet counts increased from 34 Gpt/L to 81 Gpt/L. The course was complicated by a PEM-associated pneumonitis at ∼5 months after the start of therapy. During this period, PEM was stopped for 8 weeks, and the patient lost his platelet response subsequently. Response was regained after reintroduction of therapy. sAML, secondary AML.