Successful treatment of myeloid blast phase chronic myelogenous leukemia with the JAK2 V617 F mutation by combination therapy with asciminib and ropeginterferon alfa-2b in an elderly patient.

The co-occurrence of JAK2 V617F mutations and the BCR::ABL1 translocation in the same patient is rare, and the current standard treatment for aggressive myeloid blast phase chronic myeloid leukemia (CML-myeloid BP) with JAK2 V617F mutations remains inadequate, particularly in transplant-ineligible patients. Asciminib, a first-in-class allosteric inhibitor of BCR::ABL1 kinase that specifically targets the ABL1 myristoyl pocket, has emerged as a novel alternative to standard tyrosine kinase inhibitor (TKI) therapy. Ropeginterferon alfa-2b (ropegIFNα2b) is a novel site-selective, monopegylated recombinant human IFN with long-term safety and efficacy in patients with polycythemia vera (PV). Here, we report a case of successful combination therapy with asciminib and ropegIFNα2b in a patient with CML-myeloid BP who had a long history of PV with JAK2 V617F refractory to induction chemotherapy with several TKIs. The combination of asciminib and ropegIFNα2b is a promising new treatment option for these patients.