Reducing the dose of ibrutinib is a “reasonable treatment approach for patients with intolerable side effects,” according to a recent study.
Shayna Sarosiek, MD, of the Dana Farber Cancer Institute and Harvard Medical School, and colleagues conducted the research and published their findings in the British Journal of Haematology.
They conducted the research because ibrutinib intolerance “frequently leads to dose reductions, though the impact of reducing ibrutinib dosing has not been systematically studied.”
Retrospective Study Evaluates Frequency, Impact of Ibrutinib Dose Reduction
The retrospective study included 353 patients with Waldenström macroglobulinaemia. More than one-quarter (27%) of the patients required a dose reduction due to adverse events (AEs) with a median treatment time of 64 months. The AEs included musculoskeletal symptoms, cardiac events, dermatologic symptoms, cytopenias, and gastrointestinal symptoms. The median time to the initial ibrutinib dose reduction was 9.3 months (range, 0.5 to 74 months).
Approximately two-thirds (65%) of patients showed “improvement or resolution” of AEs after the initial ibrutinib dose reduction, according to Dr. Sarosiek and colleagues. Most patients (79%) had a sustained or deepened hematologic response with a median follow-up of three years after dose reduction.
Patients who were aged 65 years or older had significantly more dose reductions than those who were under 65 years of age (hazard ratio [HR], 2.46; 95% CI, 1.55-3.90; P<.001). Dose reductions were also more common in patients who were female (HR, 2.20; 95% CI, 1.41-3.28; P<.001).
“These data suggest that dose reduction of ibrutinib is a reasonable treatment approach for patients with intolerable side effects,” Dr. Sarosiek and colleagues concluded.
Sarosiek S, Gustine JN, Flynn CA, et al. Dose reductions in patients with Waldenström macroglobulinaemia treated with ibrutinib. Br J Haematol. 2023;201(5):897-904. doi:10.1111/bjh.18643