In the updated analysis of phase III RESONATE-2 trial, treatment with BTK inhibitor (#ibrutinib) for at least 5 years showed favourable response rates and tolerability in patients with previously untreated chronic lymphocytic leukemia/small lymphocytic lymphoma without del(17p). In this randomized trial, eligible patients were randomly assigned to receive 420 mg of ibrutinib once daily until disease progression or unacceptable toxicity (n = 136) or 0.5 mg/kg of chlorambucil on days 1 and 15 of every 28-day cycle for up to 12 cycles (n = 133).

With up to 8 years follow-up, ibrutinib significantly improved PFS vs chlorambucil (HR, 0.154; 95% CI, 0.108-0.220). The median OS was not reached with ibrutinib vs 89 months with chlorambucil (0.453; 95% CI, 0.276-0.743). There was no new safety signals with long-term ibrutinib treatment with most frequent AE being diarrhea (50%), cough (37%) and fatigue (37%).