AstraZeneca and its biologics R&D arm MedImmune have bagged US approval of Lumoxiti for the treatment of hairy cell leukaemia (HCL), marking the first new treatment option in 20 years.

The decision allows physicians to prescribe the drug for patients with relapsed or refractory HCL who have received at least two prior systemic therapies, including treatment with a purine nucleoside analog, but not for those with severe renal impairment.

HCL is a rare, chronic, and slow-growing leukaemia in which the bone marrow overproduces abnormal B cell lymphocytes. The disease can result in serious conditions such as infections, bleeding and anaemia.

Around 1,000 people are diagnosed with HCL in the US each year, and, with very few treatments available, there remains significant unmet medical need for those withe with relapsed or refractory forms of the condition.

Lumoxiti (moxetumomab pasudotox-tdfk) is a first-in-class, CD22-directed cytotoxin.

In clinical trials, 75% of patients receiving the drug achieved an overall response; 30% had a durable complete response, the firms noted.

“While many patients with hairy cell leukaemia 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,” said Robert Kreitman, 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.

“Moxetumomab pasudotox represents a promising non-chemotherapeutic agent for HCL, addressing an unmet medical need for physicians and their patients.”