Skip to main content

FDA Approves New Treatment Option for Rare Form of Lymphoma

The U.S. Food and Drug Administration (FDA) recently approved zanubrutinib (Brukinsa®) for the treatment of adult patients with Waldenström’s macroglobulinemia (WM). This is the second therapy approved specifically for the treatment of this rare type of lymphoma. Zanubrutinib is a next-generation BTK inhibitor, which is designed to provide more targeted treatment with improved tolerability. 

WM is an uncommon type of non-Hodgkin lymphoma that occurs in approximately 1,000 to 1,500 new patients each year in the U.S. It begins in plasma cells, which produce antibodies. The abnormal cells overproduce antibodies and can crowd out healthy blood cells. The disease is not curable, but typically progresses slowly and can be managed for years. Nevertheless, recurrence is common and newer, safer treatments are needed. 

WM treatment changed dramatically following discovery of certain mutations in WM cancer cells by LLS-funded investigator Steve Treon M.D., Ph.D. at the Dana-Farber Cancer Center in 2012. LLS continues to support Dr. Treon and other important WM advancements, including research at Emory University, which opens the possibility of earlier detection of WM and a novel therapeutic approach including immunotherapy to control its emergence. 

LLS also has a long-standing collaboration with International Waldenstrom’s Research Foundation (IWMF) to understand the mechanisms that induce WM, the basis of resistance to existing therapies, and to develop new therapies to eradicate WM tumor cells. 

The FDA approval of oral zanubrutinib was based on a non-comparative assessment of response and duration of response (DOR). The response rate was 77.5% in the zanubrutinib arm. Event-free DOR at 12 months was 94.4% in the zanubrutinib arm. 

The most common adverse reactions were decreased neutrophil count, upper respiratory tract infection, decreased platelet count, rash, hemorrhage, musculoskeletal pain, decreased hemoglobin, bruising, diarrhea, pneumonia, and cough. Notably, the incidence of off-target side effects, including atrial fibrillation is reduced compared to another commonly used BTK inhibitor, ibrutinib.

There is still much to be learned about WM, but the approval of zanubrutinib is an important next step in improving health outcomes and quality of life for people with this rare, incurable disease.