Earlier this week, the United States Food and Drug Administration approved the new Pfizer Inc cancer drug, Besponsa (inotuzumab ozogamicin) for the treatment of adults who have relapsed or refractory B-cell precursor acute lymphoblastic leukemia (B-cell ALL). The hope is that this new drug will help patients of the rare cancer who have had no success with other treatments.
The National Cancer Institute estimates that, this year alone, roughly 5,970 Americans will receive a diagnosis for B-cell ALL; another 1,440 will die from it.
According to the FDA’s Oncology Center for Excellence director, Dr. Richard Pazdur, MD, “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.” Also the acting director of the US Food and Drug Administration’s Center for Drug Evaluation and Research’s Office of Hematology and Oncology Products, Pazdur adds, “These patients have few treatments available and today’s approval provides a new, targeted treatment option.”
B-cell precursor ALL is rare, yes, but it can be very aggressive. This is a rapidly progressing type of cancer characterized by the bone marrow making too many B-cell lymphocytes (an immature/underdeveloped type of white blood cell). Besponsa, then, is a targeted therapy believed to work by binding specifically to the B-cell ALL cancer cells which express the CD22 antigen; this blocks the further growth of cancerous cells.
Hagop M Kantarjian, MD, was the lead author of the INO-VATE ALL trial, and noted that the drug will have many applications in the future.
“In my opinion,” he comments, “inotuzumab is well tolerated with appropriate prevention measures, and my hope is that soon in the future, inotuzumab will be used not as a single agent but in combination with chemotherapy or with other antibodies.”
In addition, former Sheba Medical Center (Israel), Childhood Leukemia Research Center professor and head of functional genomics, Shai Izraeli, MD, noted, “Clearly inotuzumab is a very effective drug,” emphasizing that any improvement in treating this disease is crucial because there even the 5-year survival rate for these relapsed or refractory patients is still less than ten percent.
The FDA has listed that the most common side effects/adverse reactions (more than 20 percent occurrence) include abdominal pain, anemia, fatigue, febrile neutropenia, hyperbilirubinemia, infection, leukopenia, thrombocytopenia, neutropenia,, hemorrhage, pyrexia, nausea, headache, and increases in transaminase level or gamma-glutamyltransferase levels.