FDA’s approval of ibrutinib to treat Waldenstrom's macroglobulinemia receives praises from LLS

The U.S. Food and Drug Administration (FDA) approval of ibrutinib (Imbruvica ®) to treat patients with Waldenstrom's macroglobulinemia(WM) is a significant advance for patients with this rare blood cancer.

The FDA approved ibrutinib for all WM patients, both as a first-line therapy and for those previously treated. The approval marks the first therapy indicated specifically for patients with WM.

Ibrutinib inhibits an enzyme, Bruton's tyrosine kinase (BTK), which promotes growth of a variety of B-cell cancers, including chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), and WM.

Waldenstrom's macroglobulinemia is a rare type of B-cell lymphoma, occurring in approximately 1,500 new patients per year in the U.S. It is characterized by the overproduction of proteins called immunoglobulin M, or IgM antibodies, as well as bone marrow infiltration of tumor cells. The FDA had granted Breakthrough Therapy Designation for ibrutinib for the treatment of WM in February 2013, a program intended to expedite the development and review time for a potential new medicine to treat a serious or life-threatening disease or condition if preliminary clinical evidence suggests it provides substantial improvement over existing therapies. Despite the numerous currently utilized therapies to treat WM, until now there had been no standard of care for the disease and the treatments are not curative.

"The approval of ibrutinib is a very promising development for patients with Waldenstrom's macroglobulinemia," said Louis J. DeGennaro, The Leukemia & Lymphoma Society's (LLS) president and CEO. "While most WM patients respond to combinations of chemotherapy, recurrence is common, and therefore there remains a significant unmet medical need for a significant number of patients."

LLS has supported research to advance the understanding of the role of the BTK protein in the proliferation of several types of B-cell blood cancers. Ibrutinib received FDA approval in November 2013 to treat patients with relapsed MCL, in February 2014 to treat relapsed CLL patients and in July 2014 to treat CLL patients with 17 p deletion.

LLS remains committed to developing further improved therapies for WM by supporting additional studies at Dana-Farber Cancer Institute designed to explore new therapeutic targets for the control of WM.