Multinational phase 2 trial of pemigatinib for myeloid/lymphoid neoplasms with FGFR1 rearrangement

Myeloid/lymphoid neoplasms with fibroblast growth factor receptor 1 rearrangements (MLN-FGFR1) are associated with poort prognosis. The multinational phase 2 FIGHT-203 study evaluated tht FGFR1-3 inhibitor pemigatinib for the treatment of MLN-FGFR1. The centrally reviewed overall response rate was 74%; this occurred in 96% of patients in chronic phase and 44% of patients in blast phase. A complete cytogenic response was observed in 73% of patients. The median duration of complete response was not reached (95% CI 27.9 months –not reached). Pemigatinib discontinuation, interruption, and dose reduction occurred in 11%, 64%, and 60% of patients, respectively. The authors conclude that pemigatinib manifested near complete efficacy in chronic-phase patients with MLN-FGFR1, while the complete response rate was close to 50% in blast-phase patients. Toxicities were manageable with dose modifications.