Yesterday Pfizer won FDA approval for a new drug for the treatment of relapsed / refractory acute lymphoblastic leukemia (ALL). The approval came at the important time because the treatment options for the next generation are already on the horizon.
Besponsa was approved in an accelerated mode, helped by the FDA’s breakthrough therapy and orphan drug designations. It had won a priority review in February. The drug carries a boxed warning that severe liver damage occurred in some patients that were given the targeted therapy.
But as the FDA’s Richard Pazdur, head of the FDA’s Oncology Center of Excellence, pointed out in a statement, “For adult patients with B-cell ALL whose cancer has not responded to initial treatment or has returned after treatment, life expectancy is typically low.”
The FDA said nearly 6,000 people in the U.S. will be diagnosed with ALL this year and about 1,440 will die from the disease.
The approval of Pfizer’s new drug was based on a randomized trial in which patients received either the drug or an alternative chemotherapy regimen. Among other things, the trial measured the percentage of patients with complete remission. Of the 218 evaluated patients, 35.8% who received Besponsa experienced complete remission for a median 8.0 months; compared to 17.4% getting the chemo, which resulted in a median 4.9 months.