FDA approves zanubrutinib for the treatment of adult patients with R/R MCL

On the 14^th November 2019, the U.S. Food and Drug Administration (FDA) approved zanubrutinib (BGB-3111) for the treatment of patients with relapsed/refractory (R/R) mantle cell lymphoma (MCL).¹ Earlier this year, the drug received  Breakthrough Therapy designation by the FDA and a Priority Review designation.

Zanubrutinib is an inhibitor of Bruton’s tyrosine kinase (BTK), a protein involved in pathways regulating B-cell proliferation, chemotaxis, and adhesion. The approval was granted based on the positive data from the multicentre phase II trial of zanubrutinib in patients with R/R MCL (NCT03206970), showing overall response rate (ORR) of 84% (95% CI: 74%, 91%), including 59% complete response (CR).² The median duration of response (DOR) was 19.5 months and the median follow-up time was 18.4 months. The supporting phase I/II single-arm trial (NCT02343120) also showed 84% ORR, including 22% CR and 62% partial response with a median DOR of 18.5 months.^1,2

The most common adverse events were decreased neutrophil and platelet count, infections of the upper respiratory tract, cough, decreased white blood cell count, decreased hemoglobulin, rash, and diarrhea.¹

Clinical trials of zanubrutinib as a single agent are also ongoing in patients with untreated MCL and Waldenström macroglobulinemia. Other studies investigate the combination of zanubrutinib and obinutuzumab for treatment-naive and R/R chronic lymphocytic leukemia/small lymphocytic lymphoma, and R/R follicular lymphoma.