FDA approves Pfizer's Bespona for treatment of acute lymphoblastic leukemia

The Food and Drug Administration has approved a new medicine for treating a rapidly progressing blood cancer after the failure of other treatments.

The agency approved Pfizer Inc's Besponsa for patients suffering from an acute lymphoblastic leukemia. Life expectancy in the cancer is low.

"These patients have few treatments available and today's approval provides a new, targeted treatment option," Dr Richard Pazdur, the FDA's director for cancer drugs, said in a statement.

As per the National Cancer Institute, an estimated 5,970 Americans will be diagnosed with the cancer and 1,440 will die from it, according to the National Cancer Institute.

The cost of the drug is $168,300 without insurance for the typical nine-week treatment course.

In testing involving 218 patients, 36 per cent who had taken Bespona saw their cancer vanish for eight months on average, while 17 per cent of those give chemotherapy had complete remission for a median five months.

The drug is believed block the growth of cancerous cells by binding to their surface.

The potent injected drug, chemically as inotuzumab ozogamicin, carries the FDA's most-stringent warning because it can cause severe liver disease, including blocking veins in the liver.

Meanwhile, the FDA said in a press release, ''The U.S. Food and Drug Administration today approved Besponsa (inotuzumab ozogamicin) for the treatment of adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL).''

B-cell precursor ALL is a rapidly progressing type of cancer in which the bone marrow makes too many B-cell lymphocytes, an immature type of white blood cell. The National Cancer Institute estimates that approximately 5,970 people in the United States will be diagnosed with ALL this year and approximately 1,440 will die from the disease.

Besponsa is a targeted therapy that is thought to work by binding to B-cell ALL cancer cells that express the CD22 antigen, blocking the growth of cancerous cells.

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 one or two prior treatments. Patients were randomized to receive treatment with Besponsa or an alternative chemotherapy regimen. The trial measured the percentage of patients with no evidence of disease and full recovery of blood counts after treatment (complete remission or CR). Of the 218 evaluated patients, 35.8 percent who received Besponsa experienced CR for a median 8.0 months; of the patients who received alternative chemotherapy, 17.4 per cent experienced CR for a median 4.9 months.

Common side effects of Besponsa include low levels of platelets (thrombocytopenia), low levels of certain white blood cells (neutropenia, leukopenia), infection, low levels of red blood cells (anemia), fatigue, severe bleeding (hemorrhage), fever (pyrexia), nausea, headache, low levels of white blood cells with fever (febrile neutropenia), liver damage (transaminases and/or gamma-glutamyltransferase increased), abdominal pain and high levels of bilirubin in the blood (hyperbilirubinemia).