Pfizer’s treatment for adults with newly diagnosed acute myeloid leukaemia whose tumors express the CD33 antigen (CD33-positive AML), Mylotarg (gemtuzumab ozogamicin), has been approved by the US Food and Drug Administration (FDA).
Approval
Mylotarg, which was originally granted accelerated approval as a standalone treatment in 2000 for CD33-positive AML patients who had relapsed, was voluntarily withdrawn from the market after clinical benefit of the treatment was not verified by subsequent confirmatory trials and safety concerns (a high number of early deaths) were demonstrated.
This recent approval has been made on a lower recommended dose, a different schedule in combination with chemotherapy or on its own, and a new patient population.
“We are approving Mylotarg after a careful review of the new dosing regimen, which has shown that the benefits of this treatment outweigh the risk,” said Dr Richard Pazdur, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Mylotarg’s history underscores the importance of examining alternative dosing, scheduling and administration of therapies for patients with cancer, especially in those who may be most vulnerable to the side effects of treatment.”
In addition to adult patients, the FDA has approved this therapy for use in patients aged 2 years and older with CD33-positive AML who have experienced a relapse or who have not responded to initial treatment (refractory).
“The FDA approval of MYLOTARG fills a critical unmet need for many adults and children with AML, which can be fatal in a matter of months or even weeks if not treated and has a high relapse rate,” said Liz Barrett, global president, Pfizer Oncology. “Based on clinical data, real-world experience and support from the AML community, we are grateful MYLOTARG now has the potential to help a broad range of AML patients.”