FDA approved a targeted new drug to treat adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL).
Inotuzumab ozogamicin (Besponsa, Pfizer) treats the rapidly progressing type of cancer in which the bone marrow makes too many B-cell lymphocytes. Besponsa is a targeted therapy that binds to B-cell ALL cancer cells that express the CD22 antigen, blocking the growth of cancerous cells.
“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,” said Richard Pazdur, MD, director of FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in FDA’s Center for Drug Evaluation and Research, in a FDA statement. “These patients have few treatments available and today’s approval provides a new, targeted treatment option.”
The safety and efficacy of Besponsa were studied in a randomized trial of 326 patients with relapsed or refractory B-cell ALL who had received 1 or 2 prior treatments. Of the 218 evaluated patients, 35.8% who received Besponsa experienced complete remission for a median of 8 months. Of the patients who received alternative chemotherapy, 17.4% experienced complete remission for a median 4.9 months.
Besponsa includes a boxed warning that severe liver damage (hepatotoxicity), including blockage of veins in the liver (veno-occlusive disease [VOD] or sinusoidal obstruction syndrome) occurred in some patients who took Besponsa. The boxed warning also includes an increased risk of death for patients who take Besponsa after receiving a certain type of stem cell transplant.
Other serious side effects of Besponsa include a decrease in blood cell and platelet production (myelosuppression), infusion-related reactions and problems with the heart’s electrical pulses (QT interval prolongation).