Pemigatinib Shows Potential for First Effective Treatment for FGFR1-Mutant Myeloid, Lymphoid Neoplasms
Preliminary results from the ongoing FIGHT-203 study of pemigatinib in patients with FGFR1-mutant myeloid and lymphoid neoplasms (MLN) suggest that pemigatinib may offer utility as a bridge for allogeneic hematopoietic stem cell transplant (HSCT), or as a long-term treatment option for patients who are ineligible for transplant.
FGFR1-mutant MLN may present with chronic or blast phase (BP) involvement of bone marrow.
“Given the poor prognosis of FGFR1-mutant MLN and the potential for transformation to BP, a primary goal is to achieve deep responses to bridge patients to allogeneic hematopoietic stem cell transplant (HSCT),” wrote lead author Jason Gotlib, MD, MS, Division of Hematology, Stanford Cancer Institute, and co-authors.
FIGHT-203 is a phase 2, multicenter trial with a total of 34 patients enrolled with FGFR1-mutant neoplasms. Patients without prior therapy were also eligible and the starting dose was 13.5 mg daily on a continuous schedule. The primary endpoint is the complete response (CR) rate, and secondary endpoints include rates of overall response (ORR) comprising CR + PR, CCyR or partial CyR (PCyR), and safety.
Among the 31 pts with BM and/or extramedullary disease, CR rates per investigator and centralized review assessments were 64.5% and 77.4%, respectively. Among the 33 patients evaluable for CyR, CCyR rates were 72.7% and 75.8%, respectively. Grade 3 or higher treatment-emergent adverse events (TEAEs) in ≥10% of patients were anemia (18%), and pain in extremity and stomatitis (both 12%).
“Pemigatinib is the first therapy to demonstrate durable and high rates of CR and CCyR in pts with FGFR1-mutant MLN, most of whom had progressed on prior therapies including intensive chemotherapy or HSCT. The safety profile was consistent with FGFR inhibition with no unexpected toxicities,” wrote Dr Gotlib, et al.
Gotlib J, Kiladjian J, Vannucchi A, et al. A Phase 2 Study of Pemigatinib (FIGHT-203; INCB054828) in Patients with Myeloid/Lymphoid Neoplasms (MLNs) with Fibroblast Growth Factor Receptor 1 (FGFR1) Rearrangement (MLNFGFR1). https://ash.confex.com/ash/2021/webprogram/Paper148103.html. Presented at: the 63rd ASH Annual Meeting & Exposition; December 11-14, 2021; Atlanta, GA. Abstract 385.).
