Ibrutinib is a tyrosine kinase inhibitor indicated for the treatment of mantle cell lymphoma, chronic lymphocytic leukaemia (CLL), small lymphocytic lymphoma (SLL), and Waldenstrom’s macroglobulinaemia. This orally active agent inhibits a number of malignant B cell processes including proliferation and survival. In vitro studies also demonstrate inhibition of cell migration and substrate adhesion.
From 1st December 2017, ibrutinib will be available on the Pharmaceutical Benefits Scheme (PBS) for eligible patients with relapsed or refractory CLL or SLL. The Pharmaceutical Benefits Advisory Committee (PBAC) recommended the listing of ibrutinib based on favourable safety and efficacy data. The RESONATE trial of previously treated CLL and SLL patients demonstrates a 78% reduction in the risk of progression or death for ibrutinib compared to ofatumumab. A five-year follow-up study of patients with treatment-naïve or relapsed/refractory CLL or SLL shows durable response with an overall response rate of 89%. Importantly, no unexpected late safety events were uncovered in this trial.
The most commonly reported adverse events classified as severe or greater are hypertension, pneumonia, neutropenia, and atrial fibrillation. Complete blood count and liver function should be monitored during therapy. Regular skin examinations should also be performed due to the increased frequency of non-melanoma skin cancer in patients taking this medication.
- Byrd JC, Brown JR, O’Brien S, Barrientos JC, Kay NE, Reddy NM, et al. Ibrutinib versus ofatumumab in previously treated chronic lymphoid leukemia. N Engl J Med. 2014; 371: 213-23.
- Coutré SE, Furman RR, Flinn IW, Burger JA, Blum K, Sharman J, et al. Extended treatment with single-agent ibrutinib at the 420 mg dose leads to durable responses in chronic lymphocytic leukemia/small lymphocytic lymphoma. Clin Cancer Res. 2017; 23(5): 1149-55.
- Imbruvica® (ibrutinib) Australian approved product information. Macquarie Park: Janssen-Cilag Pty Ltd. Approved November 2016.
- O’Brien SM, Furman RR, Coutré SE, Flinn IW, Burger J, Blum K, et al. Five-year experience with single-agent ibrutinib in patients with previously untreated and relapsed/refractory chronic lymphocytic leukemia/small lymphocytic leukemia. Blood 2016; 128: 233.