The FDA on September 13, 2018 approved LUMOXITI®, a CD22-directed cytotoxin indicated for adult patients with Relapsed or Refractory Hairy Cell Leukemia (HCL) who received at least two prior systemic therapies, including treatment with a Purine Nucleoside Analog (PNA). LUMOXITI® is a product of AstraZeneca Pharmaceuticals LP.
SUMMARY: Hairy cell leukemia (HCL) is a relatively indolent disorder with characteristic immunophenotypic findings. In spite of the lack of clear understanding of the molecular biology of HCL, treatment with purine nucleoside analogs has resulted in long term remissions and cure. To under the genetic abnormalities in patients with HCL, Tiacci and colleagues evaluated the peripheral blood of 48 patients with HCL. They noted that all 48 patients had BRAF V600E mutation. This is the same mutation that has been noted in approximately 50% of the patients with melanoma. They further tested the peripheral blood of 5 patients in vitro with BRAF inhibitor vemurafenib. This drug indeed demonstrated efficacy by markedly decreasing phosphorylated ERK and MEK. This interesting finding may help us better understand the pathogenesis of HCL and targeted therapy with BRAF inhibitors may change the way we treat patients with HCL. N Engl J Med 2011; 364:2305-2315