The Food and Drug Administration (FDA) has approved Brukinsa® (zanubrutinib) for the treatment of adults with Waldenström macroglobulinemia.
The approval was based on efficacy and safety data from the randomized, active-controlled, open-label phase 3 ASPEN trial (ClinicalTrials.gov Identifier: NCT03053440), which compared zanubrutinib with ibrutinib in 201 adults with MYD88 L265P mutation (MYD88MUT) Waldenström macroglobulinemia. In Cohort 1, patients were randomly assigned 1:1 to receive zanubrutinib 160mg twice daily or ibrutinib 420mg once daily until disease progression or unacceptable toxicity.
The major efficacy outcome was response rate defined as a partial response or better, as assessed by an independent review committee based on the Sixth International Workshop on Waldenström Macroglobulinemia response criteria. A key secondary endpoint was the duration of response.
Results showed a response rate of 77.5% (95% CI, 68.1%-85.1%) in the zanubrutinib arm compared with 77.8% (95% CI, 68.3%-85.5%) with ibrutinib. At 12 months, event-free duration of response was 94.4% (95% CI, 85.8%-97.9%) in the zanubrutinib arm and 87.9% (95% CI, 77.0%-93.8%) in the ibrutinib arm. Additionally, response in Cohort 2, which included patients with MYD88 wildtype or MYD88 mutation unknown Waldenström macroglobulinemia, was observed in 50% of evaluable patients (n=13/26; 95% CI, 29.9%-70.1%).
The most common adverse reactions, including laboratory abnormalities, with zanubrutinib were decreased neutrophil count, upper respiratory tract infection, decreased platelet count, rash, hemorrhage, musculoskeletal pain, decreased hemoglobin, bruising, diarrhea, pneumonia, and cough.
Brukinsa, a Bruton tyrosine kinase inhibitor, is also indicated for the treatment of adults with mantle cell lymphoma who have received at least 1 prior therapy.
The product is supplied as 80mg capsules in 120-count bottles.
- FDA approves zanubrutinib for Waldenström’s macroglobulinemia. News release. US Food and Drug Administration. August 31, 2021. Accessed September 2, 2021.
- US FDA grants Brukinsa® (zanubrutinib) approval in Waldenström’s macroglobulinemia. News release. BeiGene, Ltd. September 1, 2021. Accessed September 2, 2021. https://www.businesswire.com/news/home/20210901006049/en/U.S.-FDA-Grants-BRUKINSA%C2%AE-Zanubrutinib-Approval-in-Waldenstr%C3%B6m%E2%80%99s-Macroglobulinemia.
- Brukinsa [package insert]. San Mateo, CA: BeiGene USA, Inc; 2021.