Long-Term Studies Assessing Outcomes of Ibrutinib Therapy in Patients With Del(11q) Chronic Lymphocytic Leukemia

Abstract

Background: Certain genomic features, such as del(11q), expression of unmutated immunoglobulin heavy-chain variable region (IGHV) gene, or complex karyotype, predict poorer outcomes to chemotherapy in patients with chronic lymphocytic leukemia (CLL).

Patients and methods: We examined the pooled long-term follow-up data from PCYC-1115 (RESONATE-2), PCYC-1112 (RESONATE), and CLL3001 (HELIOS), comprising a total of 1238 subjects, to determine the prognostic significance of these markers in patients treated with ibrutinib.

Results: With a median follow-up of 47 months, ibrutinib-treated patients had longer progression-free survival (PFS) than patients treated in the comparator arm, regardless of genomic risk factors. Among patients treated with ibrutinib, we found that high-risk genomic features were not associated with shorter PFS (63-75% across all subgroups at 42 months) or overall survival (79-83% across all subgroups at 42 months). Surprisingly, we observed that ibrutinib-treated patients with del(11q) actually had a significantly longer PFS than ibrutinib-treated patients without del(11q) (42-month PFS rate 70% vs. 65%, P = .02).

Conclusion: These analyses not only demonstrate that genomic risk factors previously associated with poor outcomes lose their adverse prognostic significance but also that del(11q) can be associated with a superior PFS with ibrutinib therapy.

Keywords: Prognostic factors; Risk factors; Small lymphocytic lymphoma; Survival.