The Food and Drug Administration (FDA) has approved pemigatinib for treating patients with relapsed or refractory myeloid/lymphoid neoplasms (MLNs) and rearrangement of fibroblast growth factor receptor 1 (FGFR1).
In 2020, the FDA approved FGFR inhibitor (pemigatinib) for patients with locally advanced or metastatic cholangiocarcinomas they show fusion or other rearrangement of FGFR2. Similarly, pemigatinib can be also used for MLN patients with FGFR1 rearrangements. The current approval is based on the findings from the FIGHT-203 study.
The single arm, multicentre, phase-2 FIGHT-203 study enrolled pateints (n=28) with relapsed or refractory MLNs with FGFR1 rearrangement. The participants had either experienced relapse after, not been candidates for allogeneic hematopoietic stem cell transplantation (HSCT) or other treatments. All the patients were administered pemigatinib (13.5 mg/day) either continuously for 21 days or intermittently (14 days on, 7 days off) until either disease progression, severe toxicity or ability to undergo allogeneic HSCT.
A higher complete response rate of 78% (95% CI, 52-94) was seen in 18 patients with chronic-phase disease in the marrow with or without extra medullary disease. Also, complete response was achieved in a median time of 104 days. Two out of four patients with blast-phase disease in the marrow and one in three with only extramedullary disease reported complete response in 94 and 64 days respectively. Finally, a complete cytogenic response rate of 79% was seen among all the patients. Adverse events were observed in at least 20%.
The high complete response and complete cytogenic response with pemigatinib in MLN patients has led to its accelerated approval by FDA as first-line treatment.