AZ's new leukaemia drug approved in the US

The FDA has approved a new cancer drug from AstraZeneca, the first medicine to treat a rare and life-threatening form of leukaemia to hit the market for 20 years.

Developed by AZ’s MedImmune biologics arm, Lumoxiti (moxetumomab pasudotox-tdfk) is approved for adults with relapsed or refractory hairy cell leukaemia.

Patients must have received at least two prior systemic therapies, including a purine nucleoside analog (PNA) to be eligible, and must not have severe renal impairment.

Late-stage trial results showed 75% of patients achieved an overall response, while 30% had a durable response.

Complete response is defined as clearing of the bone marrow of hairy cells, as measured by a series of stains and radiographic tests.

Lumoxiti was approved using a faster six-month Priority Review, based on data from the phase III single-arm open-label ‘1053’ trial as a monotherapy in 80 patients who have received at least two prior therapies, including a PNA.

Primary endpoint was durable complete response.

Dave Fredrickson, global head of AstraZeneca’s oncology business unit, said: “Today’s FDA approval of Lumoxiti represents a significant milestone for people living with hairy cell leukaemia, 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.”

Lumoxiti, formerly CAT8015 or HA22 is a CD22-directed cytotoxin. It comprises the CD22 binding portion of an antibody fused to a truncated bacterial toxin; the toxin inhibits protein synthesis and ultimately triggers apoptotic cell death.

While Lumoxiti is unlikely to be the company’s biggest selling drug, it is part of a new generation of medicines that AZ hopes will revive the company after several blockbusters went off-patent.

There have been some successes – such as its blockbuster lung cancer drug Tagrisso – but AZ has struggled to compete in the cancer immunotherapy market.

AZ’s PD-L1 class checkpoint inhibitor Imfinzi is one of AZ’s biggest hopes but has so far failed to produce results in the highly lucrative first line lung cancer indication.

Interim results of the phase III MYSTIC trial of Imfinzi in combination with tremelimumab did not show a progression-free survival benefit compared with chemotherapy in first-line lung cancer in a read-out last year, although overall survival figures are due in the coming weeks.

AZ’s executive director and CEO Pascal Soriot has set a target of sales exceeding $40 billion by 2023.