The U.S. Food and Drug Administration today expanded the approved use of Imbruvica (ibrutinib) for patients with Waldenström’s macroglobulinemia (WM), a rare form of cancer that begins in the body’s immune system. The drug received a breakthrough therapy designation for this use.

A type of non-Hodgkin lymphoma, WM usually gets worse slowly over time and causes abnormal blood cells, known as B lymphocytes (B-cells), to grow within the bone marrow, lymph nodes, liver, and spleen. In WM, abnormal B-cells also overproduce a protein known as immunoglobulin M or IgM (macroglobulin) that may lead to excess bleeding, problems with vision and with the nervous system.

According to the National Cancer Institute, approximately 70,800 Americans were diagnosed and 18,990 died from non-Hodgkin lymphomas in 2014. Imbruvica works by blocking the enzyme that allows the abnormal B-cells in WM to grow and divide.

“Today’s approval highlights the importance of development of drugs for supplemental indications,” said Richard Pazdur, M.D., director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Continued research has discovered new uses of Imbruvica.”

The FDA initially granted Imbruvica accelerated approval in November 2013 for use in patients with mantle cell lymphoma who received one prior therapy. In February 2014, the FDA granted accelerated approval to Imbruvica for use in patients with previously treated chronic lymphocytic leukemia (CLL), and then in July 2014, expanded its use to include treatment of CLL patients who carry a deletion in chromosome 17.

For more details, go to: http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm432123.htm