About ibrutinib (Imbruvica®)

  • Ibrutinib was the first of a new class of highly targeted therapies called Bruton’s Tyrosine Kinase (BTK) inhibitors, which work by blocking signals to the leukaemia cells, resulting in control of the disease.
  • Ibrutinib is registered in New Zealand by Medsafe for the treatment of several haematological disorders, including:
    • Patients with CLL (newly diagnosed and relapsed/refractory)
    • Patients with CLL with deletion 17p (newly diagnosed and relapsed/refractory)
    • Patients with Waldenström’s macroglobulinemia (WM)
    • Patients with mantle cell lymphoma (MCL) who have received at least one prior therapy.
  • Ibrutinib enables people with CLL to live longer without disease progression, while maintaining quality of life (Burger et al., 2020; Dimopoulos et al., 2018; Dreyling et al., 2016; Munir et al., 2019).
  • Ibrutinib is an oral tablet allowing patients the convenience of home-based administration, along with avoiding additional burden on hospital-based infusion clinics where many cancer treatments are traditionally administered (e.g., intravenous chemotherapies).
  • Newly diagnosed CLL patients treated with ibrutinib versus chlorambucil benefit with significantly improved rates of progression-free survival (PFS) after 5 years of follow-up. Estimated PFS for ibrutinib is 70% versus 12% for chlorambucil (HR: 0.146; 0.098–0.218) (Burger et al., 2020).
  • Patients with relapsed or refractory CLL treated with ibrutinib versus ofatumumab also benefit with significantly longer PFS (44.1 versus 8.1 months respectively; HR: 0.148; p<0.001) (Munir et al., 2019).
  • Ibrutinib benefit is consistent in newly diagnosed and relapsed/refractory patients with high-risk disease which is typically more difficult to treat and carries a poorer prognosis (i.e., del17p, TP53 mutation, del11q) (Burger et al., 2020; Munir et al., 2019).
  • Treatment of CLL with ibrutinib (newly diagnosed, relapsed/refractory and high-risk disease) is preferred by internationally recognised guidelines for CLL (NCCN, 2021).

References:

Burger, J. A., Barr, P. M., Robak, T., Owen, C., Ghia, P., Tedeschi, A., . . . Kipps, T. J. (2020). Long-term efficacy and safety of first-line ibrutinib treatment for patients with CLL/SLL: 5 years of follow-up from the phase 3 RESONATE-2 study. Leukemia, 34(3), 787-798. doi:10.1038/s41375-019-0602-x

Dimopoulos, M. A., Tedeschi, A., Trotman, J., García-Sanz, R., Macdonald, D., Leblond, V., . . . Buske, C. (2018). Phase 3 Trial of Ibrutinib plus Rituximab in Waldenström’s Macroglobulinemia. N Engl J Med, 378(25), 2399-2410. doi:10.1056/NEJMoa1802917

Dreyling, M., Jurczak, W., Jerkeman, M., Silva, R. S., Rusconi, C., Trneny, M., . . . Rule, S. (2016). Ibrutinib versus temsirolimus in patients with relapsed or refractory mantle-cell lymphoma: an international, randomised, open-label, phase 3 study. Lancet, 387(10020), 770-778. doi:10.1016/s0140-6736(15)00667-4

Munir, T., Brown, J. R., O’Brien, S., Barrientos, J. C., Barr, P. M., Reddy, N. M., . . . Woyach, J. A. (2019). Final analysis from RESONATE: Up to six years of follow-up on ibrutinib in patients with previously treated chronic lymphocytic leukemia or small lymphocytic lymphoma. Am J Hematol, 94(12), 1353-1363. doi:10.1002/ajh.25638

NCCN. (2021). NCCN Clinical Practice Guidelines in Oncology: Chronic Lymphocytic Leukemia/ Small Lymphocytic Lymphoma Version 4.2021 — April 29, 2021. Retrieved from https://www.nccn.org/professionals/physician_gls/pdf/cll.pdf