FDA approves new treatment for people with hairy cell leukemia

AstraZeneca and MedImmune, its global biologics research and development arm, announced today that the US Food and Drug Administration (FDA) has approved LUMOXITI^™ (moxetumomab pasudotox-tdfk) for the treatment of adult patients with relapsed or refractory hairy cell leukemia (HCL) who have received at least two prior systemic therapies, including treatment with a purine nucleoside analog. LUMOXITI is not recommended in patients with severe renal impairment (CrCl ≤ 29 mL/min). The Phase III trial results demonstrated 75% (95% confidence interval [CI]: 64, 84) of patients receiving LUMOXITI achieved an overall response; 30% (95% CI: 20, 41) had a durable complete response.

Dave Fredrickson, Executive Vice-President, Global Head Oncology Business Unit, said: "Today's FDA approval of LUMOXITI represents a significant milestone for people living with hairy cell leukemia, a rare blood cancer that can result in serious and life-threatening conditions. For patients, this approval provides the first FDA-approved medicine for this condition in more than 20 years."

Robert J. Kreitman, MD, Senior Investigator, Head of Clinical Immunotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, and Principal Investigator of the Phase III clinical trial, said: "While many patients with hairy cell leukemia experience a remission with current treatments, 30% to 40% will relapse five to ten years after their first treatment. With subsequent treatments, durations of response diminish and toxicities accumulate, and few approved treatment options exist. Moxetumomab pasudotox represents a promising non-chemotherapeutic agent for HCL, addressing an unmet medical need for physicians and their patients."

LUMOXITI was approved under FDA Priority Review. The approval is based on data from the Phase III single-arm, open-label '1053' trial of LUMOXITI monotherapy in 80 patients who have received at least two prior therapies, including a purine nucleoside analog. The primary endpoint of the trial was durable complete response. Summary of key results from the trial, as determined by a blinded independent central review:

The median time to hematologic remission was 1.1 months (range: 0.2 to 13). At data cut-off, the median duration of complete response was not yet reached after a median 16.7 months of follow-up.

Capillary leak syndrome (CLS) and hemolytic uremic syndrome (HUS), including life-threatening cases of each, have been reported among patients treated with LUMOXITI. In the combined safety database of 129 HCL patients treated with LUMOXITI, Grade 3 or 4 CLS occurred in 1.6% and 2% of patients, respectively. Grade 3 or 4 HUS occurred in 3% and 0.8% of patients, respectively.

In the '1053' trial of 80 patients, the most common Grade 3 or 4 adverse reactions (reported in at least ≥ 5% of patients) were hypertension, febrile neutropenia, and HUS. HUS was the most common adverse reaction leading to discontinuation (5%). The most common adverse reactions (≥ 20%) of any grade were infusion related reactions (50%), edema (39%), nausea (35%), fatigue (34%), headache (33%), pyrexia (31%), constipation (23%), anemia (21%), and diarrhea (21%). The most common laboratory abnormalities (≥ 20%) of any grade were creatinine increased, ALT increased, hypoalbuminemia, AST increased, hypocalcemia, hypophosphatemia, hemoglobin decreased, neutrophil count decreased, hyponatremia, blood bilirubin increased, hypokalemia, GGT increased, hypomagnesemia, platelet count decreased, hyperuricemia, and alkaline phosphate increased.

The recommended dose of LUMOXITI is 0.04 mg/kg administered as an intravenous infusion over 30 minutes on days 1, 3, and 5 of each 28-day cycle up to 6 cycles, disease progression, or unacceptable toxicity.