- At up to 6 years' follow-up of RESONATE in patients with relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (R/R CLL/SLL), extended ibrutinib therapy maintained survival advantages over ofatumumab with no evidence of new safety signals.
Why this matters
- Ibrutinib reduced burden of treatment in this setting as a first-in-class Bruton’s tyrosine kinase inhibitor with once-daily oral dosing.
- Phase 3 trial of patients randomly assigned to ibrutinib monotherapy (n=195) vs ofatumumab (n=196) in patients with relapsed/refractory CLL/SLL.
- Patients received ibrutinib until progressive disease or unacceptable toxicity; ofatumumab was given for 24 weeks.
- Median follow-up was 64 months (range, 0.3-72 months).
- Funding: PharmaCyclics, LLC, an AbbVie company.
- 68% of patients in the ofatumumab group crossed over to ibrutinib.
- Median duration of ibrutinib therapy was 41 months (>4 years, 41%).
- 88% objective response rate (ORR) with ibrutinib with 11% complete response (CR)/CR with incomplete bone recovery (Cri).
- Median PFS: overall population:
- 44.1 (95% CI, 38.5-56.2) months with ibrutinib vs 8.1 (95% CI, 7.8-8.3) with ofatumumab (HR, 0.148; P˂.0001).
- Median PFS: high-risk genomic characteristics:
- 44.1 (95% CI, 38.5-56.9) months with ibrutinib vs 8.0 (95% CI, 6.4-8.2) with ofatumumab (HR, 0.110; P˂.0001).
- Median OS with ibrutinib was 67.7 (95% CI, 61.0-not estimable [NE]) months vs 65.1 (95% CI, 50.6-NE) with ofatumumab (unadjusted for crossover/censoring).
- No new safety signals were observed.
- Open-label design.