Drug Shows Promise for Mantle Cell Lymphoma and Chronic Lymphocytic LeukemiaJun 24, 2013
Ibrutinib, a new drug under development, is showing promise as a treatment for mantle cell lymphoma and chronic lymphocytic leukemia (CLL), according to new studies. Researchers from The Ohio State University Comprehensive Cancer Center, University of Texas MD Anderson Cancer Center, and colleagues published the results of 2 studies online June 19, 2013 in the New England Journal of Medicine. The findings were first presented at the American Society of Hematology Annual Meeting and Exposition in December of last year.
Ibrutinib is a type of targeted therapy that works by interrupting certain parts of the cellular changes and signals that are needed for a cancer to develop and keep growing. Ibrutinib is taken by mouth once a day. So far it has been shown to have fewer side effects than most standard chemotherapy drugs.
Ibrutinib for mantle cell lymphoma
Mantle cell lymphoma is a type of cancer that starts in white blood cells called lymphocytes, which are part of the body’s immune system. Lymphocytes are in the lymph nodes and other lymphoid tissues. When mantle cell lymphoma is diagnosed, it is usually widespread in the lymph nodes, bone marrow, and often the spleen. A new drug to treat it would be significant, because there are few effective treatments currently available.
The study of ibrutinib in mantle cell lymphoma included 111 patients whose disease had come back or was no longer responding to other treatments. 75 of them (68%) responded to ibrutinib, meaning they started to get better. That included 23 patients (21%) who had a complete response, in whom all signs of the cancer disappeared. On average, the patients taking ibrutinib saw no worsening of their cancer for 14 months. The most common side effects were mild or moderate diarrhea, fatigue, and nausea.
Ibrutinib for CLL
CLL is another type of cancer that starts from lymphocytes in the bone marrow. Ibrutinib was tested in 85 CLL patients whose leukemia had come back or was no longer responding to other drugs. 71% of them responded to ibrutinib. After an average of 26 months, the CLL still had not become worse in 75% of patients.
While the results of these studies of ibrutinib are promising, the drug is not yet approved for use by the US Food and Drug Administration (FDA), so it isn't yet available outside of clinical trials. It was granted “breakthrough therapy” status earlier this year, qualifying it for faster FDA review.
Targeting BTK with Ibrutinib in Relapsed or Refractory Mantle-Cell Lymphoma. Published online June 19, 2013 in the New England Journal of Medicine. First author: Michael L. Wang, MD, University of Texas MD Anderson Cancer Center, Houston.
Targeting BTK with Ibrutinib in Relapsed Chronic Lymphocytic Leukemia. Published online June 19, 2013 in the New England Journal of Medicine. First author: John C. Byrd, MD, Ohio State University, Columbus, Ohio.