Lumoxiti a New Treatment Approved for Patients with Hairy-Cell Leukemia
On September 13, 2018, the FDA approved moxetumomab pasudotox-tdfk (Lumoxiti; AstraZeneca), an intravenous CD22-directed cytotoxin, for adults with relapsed or refractory hairy-cell leukemia (HCL) who received ≥2 systemic therapies, including treatment with a purine nucleoside analog. The FDA used its fast track and priority review for this approval, and it granted moxetumomab pasudotox-tdfk an orphan drug designation for this indication.
This approval was based on a clinical trial of 80 patients, including 77 patients with histologically confirmed HCL and 3 patients with HCL variant, who required treatment because of the presence of cytopenias or splenomegaly. All patients had received treatment with at least 2 systemic therapies, including a purine nucleoside analog.
Patients received an infusion with moxetumomab pasudotox-tdfk over 30 minutes on days 1, 3, and 5 of each 28-day cycle, for a maximum of 6 cycles or until complete response, disease progression, or unacceptable toxicity.
Overall, 33 (41%) patients had complete response (95% confidence interval [CI], 30-53) with moxetumomab pasudotox-tdfk, and 24 (30%) patients had a durable complete response (95% CI, 20-41), defined by maintenance of hematologic remission, based on an Independent Review Committee assessment.
Grade 3 or 4 events (≥5%) included hypertension, febrile neutropenia, and hemolytic uremic syndrome. A total of 15% of patients discontinued treatment because of side effects, 5% of which were related to hemolytic uremic syndrome. The most common (≥20%) adverse events of any grade with moxetumomab pasudotox-tdfk were infusion-related reactions, edema, nausea, fatigue, headache, pyrexia, constipation, anemia, and diarrhea.